Microbiology Case Study: A 41 Year Old Male with Pneumonia

Case Description

A 41 year old male with a past medical history significant for HIV presented to the emergency department with complaints of a fever, shortness of breath, cough, myalgias, diarrhea, and dark urine for five days. Upon presentation, he was found to meet sepsis criteria for fever of 105° F, white blood cell count of 19 x 109 /L, and tachycardia. Physical exam was unrevealing. Chest x-ray revealed a lobar pneumonia and a CT chest showed ground-glass opacities with superimposed interlobular thickening and intralobular septal thickening, commonly referred to as “crazy-paving” (Image 1). Initial laboratory assessments included CBC, CMP, blood and sputum cultures, and a T-spot. A legionella urine antigen test was ordered a short time later following an infectious disease consult.

CBC and CMP were significant for leukocytosis (19 x 109 /L), hyponatremia (130 mmol/L), and transaminitis (AST: 97, ALT: 91). Blood and sputum cultures were negative as was the T-spot. Ultimately, the diagnosis of Legionnaire’s Disease was made by the positive urine antigen test.

Image 1. Computed tomography images of the chest without contrast demonstrates consolidation and “crazy paving” patterns of radiographic pathology.
Image 2. Representative example of Legionella pneumophila on Buffered Charcoal Yeast Extract (BCYE) media with small wet gray colonies.

Discussion

Legionella is a genus of aerobic, gram negative, intracellular pathogens that are most often found in soil and water.1 There are over 60 known species of Legionella with each consisting of a varied number of serogroups. At least 26 of these species are pathogenic in humans, however only a few are responsible for the vast majority of known cases.2 In North America, upwards of 90% of cases are caused by L. pneumophila, and more specifically its serogroup 1. In Australia and New Zealand, L. longbeachae is the predominant human pathogen.3 Legionella infections most commonly cause community-acquired pneumonia after inhalation of aerosols and can less frequently cause a self-limited febrile syndrome known as Pontiac Fever. Characteristic signs that may cause a treating physician to think of Legionella infection include a constellation of symptoms that include diarrhea, hyponatremia, and elevated liver function tests.4

This case reviews a typical presentation of Legionnaire’s disease and highlights several diagnostic pearls worth remembering. Despite commonly being thought of as an exotic pathogen, Legionella is known to cause between 2%-15% of community-acquired pneumonia cases in the United States and Europe.5 The gold standard for diagnosis is culture of lower respiratory secretions, however it is a fastidious organism that is not easily picked up on gram stain or grown on standard media. When culture is attempted, nutrient enriched BCYE agar is required and the timeframe for growth must be increased to 5 to 7 days for L. pneumophila and 14 days for non-pneumophila strains (Image 2).6 Adding to the difficulty in detection, Legionella is easily treated by empiric therapies, such as macrolides, that cover atypical infections; therefore, delays in testing further reduce sensitivity. The urine antigen test does help to overcome this problem as it can detect infection within 2-3 days of symptom onset and remains positive for at least 1 month following resolution of the illness.6

References

  1. Edelstein PH and Roy CR. Legionnaires’ Disease and Pontiac Fever. In: Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases, 8, Bennet JE, Dolin R and Blaser MJ (Eds), Elsevier, Pennsylvania 2015.
  2. National Center for Biotechnology Information Taxonomy Browser. https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Tree&id=444&lvl=3&keep=1&srchmode=1&unlock (Accessed on April 14, 2021).
  3. Yu VL, Plouffe JF, Pastoris MC, et al. Distribution of Legionella species and serogroups isolated by culture in patients with sporadic community-acquired legionellosis: an international collaborative survey. J Infect Dis 2002; 186:127.
  4. Robert R. Muder, L. Yu Victor, Infection Due to Legionella Species Other Than L. pneumophilaClinical Infectious Diseases. 2002; 35(1):990-998. doi.org/10.1086/342884
  5. Chahin A, Opal SM. Severe pneumonia caused by Legionella pneumophila: differential diagnosis and therapeutic considerations. Infect Dis Clin North Am. 2017;31(1):111-121. doi:10.1016/j.idc.2016.10.009
  6. Mercante JW, Winchell JM. Current and emerging Legionella diagnostics for laboratory and outbreak investigations. Clin Microbiol Rev. 2015;28(1):95-133. doi:10.1128/CMR.00029-14

-Allen Green is a first year Clinical Pathology resident at UT Southwestern. He has broad interest in laboratory medicine and Transfusion medicine.

-Dominick Cavuoti is a full professor at UT Southwestern and practices both Medical Microbiology, Infectious Disease Pathology and Cytology.

-Clare McCormick-Baw, MD, PhD is an Assistant Professor of Clinical Microbiology at UT Southwestern in Dallas, Texas. She has a passion for teaching about laboratory medicine in general and the best uses of the microbiology lab in particular.

Microbiology Case Study: A Patient, A Toilet, and a Worm

Case History

A patient presents with a worm they found in the toilet.

Image 1. The offender.
Image 2. Mouth parts of the worm.

Discussion

This is Ascaris lumbricoides, a roundworm. Distinctive morphologic features include tapered ends, mouthparts consisting of three prominent lips (pictured in image 2), and a length of up to 35cm for females. The adults live in the duodenum and proximal jejunum. The eggs have an irregular external mamillated outer shell that gives them a roughened outer surface. Clinically, infection can range from asymptomatic to severe disease, in which the larvae, hatched from ingested eggs, migrate from the small bowel through the circulatory system to the lungs, where they mature in the alveolar capillary bed and cause Ascariasis pneumonitis (Löffler syndrome).

Other diagnostic considerations include Enterobius vermicularis (pinworm), Lumbricus terrestris (earthworm), Trichuris trichiura (whipworm), and the hook worms, Necator americanus and Ancylostoma duodenale.

Enterobius vermicularis, the pinworm, is the most common helminth infection in the United States. Clinically, the classic presentation is a child with pruritus ani. Females measure up to 1.3 cm in length and have a pointed posterior end, and both sexes have lateral alae and a prominent esophageal bulb. The worm in this case is far too large to be a pinworm.

The earthworm, Lumbricus terrestris, is soil-dwelling and non-pathogenic but occasionally encountered in the laboratory for identification purposes. Key morphologic features include a segmented body with no distinctive mouthparts and a clitellum (a mating organ that is a non-segmented portion of the body and often a different color from the rest of the body).

Trichuris trichiura, the whipworm, have a classic whip-like appearance with long, narrow anterior ends that anchor the worm to the large intestine, where they can remain for up to 10 years. Both males and females measure up to 5.0 cm in length, and diagnosis is often made by identification of the eggs, which are football-shaped and have polar plugs at both ends. Clinically, trichuriasis can cause dysentery-type symptoms and, in heavily infected children, can lead to rectal prolapse.

Necator americanus and Ancylostoma duodenale are the hookworms. Adult females measure up to 1.2 cm, and these two species are differentiated by examination of the mouthparts: Necator americanus has cutting plates, while Ancylostoma duodenale has cutting teeth. In addition to the large size difference between hookworms and roundworms, the lamprey-like appearance of these mouthparts is notably different from the “fleshy lips” of Ascaris. Hookworms and roundworms, however, are similar in that their larvae have the ability to migrate through tissue to the blood stream then the lungs, where they can cause Löffler syndrome and are expectorated then swallowed before reaching the small bowel. Unlike Ascaris, the larvae of which hatch from ingested eggs and penetrate the host through the bowel wall to get to the lung capillary beds where they can mature, hookworm larvae hatch outside the body and, on contact with a host (once again, lamprey-style), directly penetrate the skin, enter the circulation, travel to the lungs, then migrate up the bronchial tree to be swallowed. If ingested, Ancylostoma larvae can mature into adults in bowel without needing to migrate through the lungs.

References

  1. Centers for Disease Control and Prevention. “Stool Specimens – Intestinal Parasites: Comparative Morphology Tables.” https://www.cdc.gov/dpdx/diagnosticProcedures/stool/morphcomp.html. Last reviewed May 3, 2016. Accessed April 2, 2021.
  2. “Earthworms.” University of Pennsylvania. https://www.sas.upenn.edu/~rlenet/Earthworms.html. Accessed April 2, 2021.
  3. McPherson, R, and M Pincus. (2011). Henry’s Clinical Diagnosis and Management By Laboratory Methods (22nd Edition, pp. 1218-1220). Philadelphia, PA: Elsevier Saunders.

-Frederick Eyerer, MD is a 3rd year anatomic and clinical pathology resident at the University of Vermont Medical Center.

-Christi Wojewoda, MD, is the Director of Clinical Microbiology at the University of Vermont Medical Center and an Associate Professor at the University of Vermont.

Cytology Case Study: Little Gland, Big Disease

A 59 year old female initially presented with DCIS, treated by mastectomy and 5 years of adjuvant tamoxifen at another institution. 4 years later, she presented to another hospital with an adrenal mass, uterine fibroids, and an ovarian cyst, where a biopsy and right-sided adrenalectomy confirmed a 10.5 centimeter adrenocortical neoplasm. Margins were close, but negative at <0.1 cm. Microscopically there were areas of necrosis, high nuclear grade, a diffuse growth pattern, and clear cells representing less than 25% of the tumor. A malignancy was favored, but lack of metastasis could not confirm the diagnosis. She presented to the cancer center with stage II adrenal cancer, T2N0M0 and mitotane-induced adrenal insufficiency. Multiple hepatic and pulmonary metastases were subsequently identified and treated with extensive surgery, including a VATS wedge resection, right nephrectomy, hepatic mobilization, lysis of adhesions, dissection of the adrenal vein and vena cava with repair, and resection of an ileal mass.

Palliative radiation therapy targeted the remaining lung nodules, and six cycles of chemotherapy were administered. A CT scan-guided fine need aspiration biopsy was obtained of a 4 centimeter retroperitoneal mass that was suspicious for recurrence on imaging, which cytopathology then confirmed. Taking into consideration the history, my additional differentials included renal cell carcinoma, hepatocellular carcinoma, and plasmacytoma, with metastatic breast cancer as the least likely differential.

Images 1-2. Retroperitoneal mass, right side, FNA-DQ stained smears.
Images 3-4. Retroperitoneal mass, right side, FNA-Pap stained smears.
Images 5-6, Retroperitoneal mass, right side, FNA-H&E cell block sections.

Palliative radiation therapy was then administered to the retroperitoneal and psoas masses, and microwave ablation targeted the segment 3 and segment 6 liver lesions, reducing pain and stabilizing growth, respectively. However, disease continued to slowly progress, so the oncology team sent the retroperitoneal metastasis tissue for molecular testing to assess for potential next lines of therapy. Testing revealed a variant of undetermined significance in MSH6, indeterminate tumor mutational burden, stable MSI, and negative for PDL1. When the case was brought to tumor board, the team recommended ongoing surveillance and palliative therapy (when needed) given the patient’s slowly progressing disease. Often thought of as a rare disease, I’ve examined a fair share of primary and metastatic adrenocortical carcinomas through working at a cancer center. These tiny triangular glands that sit on top of the kidneys have SO much power. Producing and regulating cortisol, aldosterone, and androgenic hormones, the adrenal cortex is an active outer layer. Whether hormonal or neoplastic, it truly is fascinating how a tiny gland could wreak so much large-scale havoc on the human body.

-Taryn Waraksa, MS, SCT(ASCP)CM, CT(IAC), has worked as a cytotechnologist at Fox Chase Cancer Center, in Philadelphia, Pennsylvania, since earning her master’s degree from Thomas Jefferson University in 2014. She is an ASCP board-certified Specialist in Cytotechnology with an additional certification by the International Academy of Cytology (IAC). She is also a 2020 ASCP 40 Under Forty Honoree.

Microbiology Case Study: A 55 Year Old Man with New Onset Neurologic Deficits

Clinical History

A 55 year old male with a 43-pack-year smoking history was transferred to our hospital for evaluation of new onset neurologic deficits including slurred speech, aphasia, and right upper extremity diminished dexterity and neglect. CT chest was remarkable for a mass in the superior segment of the left lower lobe. Needle core biopsy of the lung mass revealed poorly differentiated non-small cell carcinoma. Head MRI demonstrated an enhancing mass in the left frontoparietal junction that was concerning for metastasis from a lung primary. The patient was started on chemotherapy as an outpatient. Follow-up imaging showed growth of the brain mass. A biopsy of the brain mass showed no evidence of metastasis, only “reactive brain with foci of dense mixed inflammation and filamentous bacteria consistent with abscess.”

Image 1. Head MRI demonstrating left frontoparietal mass.

Laboratory Findings

A portion of the brain biopsy was submitted for bacterial smear and culture. The aerobic culture grew chalky white colonies that, when stained with modified acid-fast stain, showed modified acid-fast positive filamentous bacteria, suspicious for Nocardia spp. Bacteria of similar morphology were also seen in the surgical pathology specimen when stained for modified AFB and with GMS.

Image 2. Blood agar plate growing chalky white colonies.
Image 3. Modified acid-fast positive filamentous bacteria at 1000x.

Disscussion

Nocardia is a genus of aerobic, catalase positive, saprophytic bacteria often found in the environment, but that can also be considered as normal flora on skin and in the respiratory tract. Nocardia species are variably acid-fast; for proper identification they must be stained with a modified acid-fast procedure (Fite, Kinyuon), using a weaker decolorizing acid. Nocardia will be negative by traditional acid-fast staining procedures (Ziehl–Neelsen). When Gram stained, Nocardia will appear as branching filamentous gram-positive bacilli with a “beaded” staining pattern (as if a string of beads). 

Multiple species are considered human pathogens, including N. asteroides, N. brasiliensis, N. cyriacigeorgica, N. farcinica, and N. nova. These organisms can cause disease in immunocompromised patients if inhaled or inoculated via trauma. If there is an established pulmonary infection, Nocardia may spread hematogenously, often infecting the brain. 

Central nervous system nocardiosis may occur in any region in the brain and can present with mass effect symptoms without typical infectious symptoms, as in our patient. Prognosis varies based on the extent of disease and the cause of a patient’s immunosuppression. Treatment of CNS nocardiosis usually begins with an induction phase of intravenous TMP-SMX and imipenem for 3-6 weeks or until there is clinical improvement. Once the patient improves, they can be switched to oral therapy with a sulfonamide and/or minocycline and/or amoxicillin-clavulanate.  

References

  • Beaman BL. Nocardia Species : Host-Parasite Relationships. 1994;7(2):213-264.
  • Spelman D. Clinical manifestations and diagnosis of nocardiosis. In: Sexton DJ, Mitty J, eds. UpToDate. UpToDate, Inc.
  • Spelman D. Microbiology, epidemiology and pathogenesis of nocardiosis. In: Sexton DJ, Mitty J, eds. UpToDate. UpToDate, Inc.
  • Spelman D. Treatment of Nocardiosis. In: Sexton DJ, Mitty J, eds. UpToDate. UpToDate, Inc.
  • Tille, Patricia M., PhD, BS, MT(ASCP) Facs. Bailey & Scott’s Diagnostic Microbiology. 14th ed. Elsevier; 2017.

-Michael Madrid, MD is a 1st year Anatomic and Clinical Pathology Resident at the University of Vermont Medical Center.

-Christi Wojewoda, MD, is the Director of Clinical Microbiology at the University of Vermont Medical Center and an Associate Professor at the University of Vermont.

Microbiology Case Study: A 53 Year Old Man with Confusion, Auditory Hallucinations, and Hearing Loss

Clinical History

A 53 year old male with a past medical history significant for dermatomyositis, antisynthetase syndrome, and atrial fibrillation with rapid ventricular response presented with a chief complaint of worsening confusion, auditory hallucinations, and hearing loss. Pertinent medications included prednisone and mycophenolate. Head MRI demonstrated leptomeningeal enhancement and hydrocephalus. A lumbar puncture was performed, with CSF results as follows:

Laboratory Findings

CSF was sent to the microbiology lab for bacterial and fungal smears and cultures. No organisms were seen on the Gram stain.

Within 3 days, however, rare colonies of yeast were growing on both the bacterial and fungal media. The yeast was identified as Cryptococcus neoformans using the in-house MALDI-TOF mass spectrometry instrument.

Image 1. Budding C. neoformans at 1000x.
Image 2. Colonies of C. neoformans on potato flake agar.

Discussion

Cryptococcus neoformans is an environmental saprophytic yeast that can be found around the world, although it is often associated with avian droppings.1 The cell is surrounded by a polysaccharide capsule that protects it from environmental hazards and, once within the host, from phagocytosis.2 Additionally, the cell wall of C. neoformans contains melanin due to the presence of the phenol oxidase enzyme, which assists in the formation of melanin from various phenolic substrates.1 Both the polysaccharide capsule and the melanin-containing cell wall can be helpful in the laboratory identification of C. neoformans.

If inhaled, Cryptococcus neoformans can cause disease (cryptococcosis) in immunocompromised patients. The most significant risk factor is AIDS, however any cause of immunodeficiency can be a risk factor, including long-term steroid therapy, organ transplantation, malignancy, and liver disease.1 Once inhaled, the organism spreads hematogenously and tends to favor the central nervous system, causing cryptococcal meningoencephalitis.1

Prognosis for patients with cryptococcosis can vary widely. In AIDS-associated CNS cryptococcosis, predictors of mortality include abnormal mental status, cerebrospinal fluid antigen titer >1:1024 by latex agglutination or >1:4000 by lateral flow assay, and CSF white blood cell count <20/µL.1 The prognosis for patients who are immunocompromised for other reasons depends on the cause of their immunosuppression.1

Treatment of patients with cryptococcal meningoencephalitis consists of an induction phase with amphotericin B and flucytosine followed by a consolidation phase with fluconazole then a long-term maintenance phase with a smaller dose of fluconazole.3

References

  1. Jobson M. Microbiology and epidemiology of Cryptococcus neoformans infection. In: Post T, ed. UpToDate. UpToDate, Inc. Accessed March 13, 2021. https://www.uptodate.com
  2. Tille, Patricia M., PhD, BS, MT(ASCP) Facs. Bailey & Scott’s Diagnostic Microbiology. 14th ed. Elsevier; 2017.
  3. Perfect JR, Dismukes WE, Dromer F, et al. Clinical practice guidelines for the management of cryptococcal disease: 2010 update by the infectious diseases society of America. Clin Infect Dis. 2010;50(3):291-322. doi:10.1086/649858

-Michael Madrid, MD is a 1st year Anatomic and Clinical Pathology resident at the University of Vermont Medical Center.

-Christi Wojewoda, MD, is the Director of Clinical Microbiology at the University of Vermont Medical Center and an Associate Professor at the University of Vermont.

Mye-Lo-Mye: Cytology Case Study

I quickly transitioned from from learning at Jefferson to teaching at Jefferson less than 6 months after I graduated from the Cytotechnology program. Assuming this new role of teaching future cytotechnologists was a refreshing twist after continuously learning at work. I stood at the podium as an alumna in my previous classroom with a breadth of fresh material to work with, appreciate, and share. At the beginning of each lecture, I would check in on my students, ask them how their other classes were going, ask if they had any questions, and then, I would share an interesting case from my work week thus far. Aside from the weekly lecture on ancillary techniques, such as molecular and immuno-diagnostics, I assigned multiple activities such as journal club/conferences, discussions, and my personal favorite – a mock tumor board. Each student would take turns playing the role of the physician, radiologist, cytotechnologist, pathologist, and oncologist (surgical, medical, or radiation). For my first year of instruction, I had assigned the group their “tumor” of interest, but I quickly encouraged their creativity run rampant during subsequent years.

Despite working in a cancer center and being able to recognize some fairly obscure tumors with little experience, I did not realize how much I still had to learn, even as a part-time lecturer and full-time cytotechnologist. These tumor boards taught me so much more than I expected, and I am forever thankful for the experience of having such wonderfully bright students teach ME! For one very memorable tumor board, the students elected to present the diagnosis and treatment of a male patient with multiple myeloma. Yes, plasma cells! Plasma cell neoplasm, plasmacytoma, multiple myeloma. Awesome, let’s see what this group can do! The “physician” said the patient complained of widespread bone pain, malaise, and recurrent fevers and infections. The “radiologist” presented the images of osteolytic lesions throughout the skull and vertebrae, the latter of which core biopsies and FNAs were obtained. The “cytotechnologist” described a mix of plasmablastic cells, as well as mature and immature plasma cells, some with clock face chromatin and a perinuclear hof (which is my telltale feature that I now emphatically describe to everyone else). The “pathologist” bypassed flow cytometry and performed Kappa/Lambda light chain immunohistochemistry on the core biopsy, diagnosing the patient with multiple myeloma. Unfortunately, due to the extent of the patient’s disease, the “oncologist” and her team could not increase the life expectancy, and the student’s patient expired.

Now, whenever I have a plasma cell neoplasm or multiple myeloma case, I think back to my students and their mock tumor board and everything they taught me. I just recently attended an FNA on a 79-year-old male with a history of multiple myeloma who presented with a PET positive right facial mass and right cervical lymph nodes. The radiologist performed an ultrasound-guided FNA of a right peri-mandibular soft tissue mass, and it took everything in me to not tell the radiologist anything more than “adequate.” But when I saw those perinuclear hofs, I was elated to have a definitive diagnosis!

Images 1-2. Perimandibular Mass, Right, FNA-DQ-stained smears.

Later that afternoon, I couldn’t wait to screen my pap-stained slides. The clock face chromatin was so beautiful! My cell block the following morning highlighted the textbook perfect features diagnostic of a plasma cell neoplasm.

Images 3-4. Perimandibular Mass, right, FNA. Pap-stained smears.
Image 5. Perimandibular Mass, Right, FNA. H&# cell block section.

The attending pathologist ordered a routine myeloma immunocytochemistry panel, including CD138, kappa light chain, lambda light chain, CD20, CD45, and MUM1.

Immunocytochemical stains performed on the unstained paraffin sections showed the tumor to be positive for CD138, kappa light chain, and MUM1, focal equivocal staining for CD20, and negative staining for lambda and CD45. The case was signed out as a plasma cell neoplasm.

Images 6-8. Perimandibular Mass, right, FNA. Cell block section immunocytochemistry. 6, CD138; 7, MUM1; 8, kappa light chain.

The bone marrow core biopsy was sent for Cytogenetic Microarray Analysis and Next Generation Sequencing. The CMA results revealed gains of chromosomes 3, 5, 9, 11, 15, 19, and 21 and losses of chromosome segments 1p and 2p and 7 p in mixed states. Loss of 1p is associated with a poorer prognosis for multiple myeloma. Next gen sequencing identified a tumor mutation burden of 8.4Muts/Mb with mutations detected in the following genes: FAM46C, BRAF, KAT6A, TSC1, KRAS, FLT3, and NFKBIA.

-Taryn Waraksa, MS, SCT(ASCP)CM, CT(IAC), has worked as a cytotechnologist at Fox Chase Cancer Center, in Philadelphia, Pennsylvania, since earning her master’s degree from Thomas Jefferson University in 2014. She is an ASCP board-certified Specialist in Cytotechnology with an additional certification by the International Academy of Cytology (IAC). She is also a 2020 ASCP 40 Under Forty Honoree.

Coagulation Case Study: 14 Year Old Female With a History of Bleeding Episodes

Case Study

A 14 year old female arrived at the emergency room with her mother and grandmother complaining of extremely heavy menstrual bleeding. Patient history reported by her mother included a history of “a bleeding problem” for which she had been treated a few times since age 4. Petechiae were noted on the girl’s abdomen, arms and thighs. There was no history of aspirin or other NSAID use. Blood work was ordered.

Patient results are shown in Table 1 below.

The mother called home to ask her husband for details and reported that her daughter had been diagnosed with Immune Thrombocytopenic Purpura (ITP) 10 years earlier but was not very clear on the treatments. She stated that other than frequent nose bleeds, some petechiae, and occasional bruising that the girl had seemed ok until she started menstruating. They had not seen the specialists in a number of years. Further questioning of the mother revealed that the parents had both immigrated from Iran with their families as infants. The patient was an only child. The grandmother reminisced about the village “in the old country” and mentioned that her daughter and son in law were related, the families being from the same village. When asked about any other family with bleeding disorders, the mother reported that neither she nor her husband had ever met any other relatives in Iran and were unaware of any bleeding tendencies in the family. The grandmother interjected that she did remember that several of her cousins and an uncle experienced frequent epistaxis.

The ER physician noted the normal PT/INR, APTT and slightly decreased platelet count but felt the extensive petechiae and hypermenorrhagia were out of proportion to these results. A manual differential was ordered. Differential results were within normal ranges, RBC morphology reported sight polychromasia and anisocytosis. Platelet estimate was slightly decreased with giant platelets noted. The physician suspected an inherited platelet disorder and the patient was referred to a hematologist for further workup.

Image 1. Giant platelets on peripheral blood smear.
Image 2. Giant platelets.

Discussion

I have written a few blogs about different thrombocytopenias. This case interested me because the patient was first diagnosed with ITP. ITP is an autoimmune bleeding disorder in which the immune system makes anti-platelet antibodies which bind to platelets and cause destruction. Even though the exact cause of ITP remains unknown, it is recognized that it can follow a viral infection or live vaccinations. In children this tends to be an acute disease which is self-limiting and self resolves in several weeks. However, in a small number of children, ITP may progress to a chronic ITP, as was thought to be the case in this patient.

A new hematologist saw the patient and reviewed the medical history. In this patient, the diagnosis of ITP had been followed for a short period of time in which the platelet count did not increase. She was treated with immunoglobulin. When her platelet count dropped below 30 x 103/μL, the patient was transfused several times. Early platelet transfusions increased her counts, but the patient became refractory and was then given HLA matched platelets, with some improvement. After a period of time, the patient did not return to the specialist and the parents described her condition as improved. However, as reported to the ER physician, she still experienced frequent epistaxis and other bleeding symptoms unrelated to accidental injury. The mild thrombocytopenia and giant platelets on the blood smear with normal PT and APTT in a patient with abnormal bruising or bleeding alerted the physician to the possibility of the diagnosis of Bernard Soulier Syndrome (BSS). The family history also suggested BSS.

The hematologist ordered further testing. Noted in the patients chart from 10 years ago was a prolonged bleeding time. This test was not repeated at this time because it has largely been replaced by platelet function analyzers (PFAs.) The PFA test analyzes platelet function by aspirating citrated blood through membranes to induce platelet adhesion and platelet plug formation. The test is first performed with a collogen and epinephrine membrane (Col/Epi). If the closure time is normal, platelet function can be considered normal. If the closure time with Col/Epi is increased, then the test is repeated with a collogen and ADP membrane (Col/ADP). A prolonged closure time with Col/Epi with normal Col/ADP closure time may indicate an aspirin induced platelet disorder, whereas an increased closure time with both membranes may indicate a platelet defect that is not aspirin related.3 The PFA closure times were increased in both the Epinephrine and ADP cartridges.

Platelet aggregation was normal with all agents except ristocetin. BSS can be differentiated from von Willebrand disease(vWD) by the addition of normal plasma to the ristocetin agglutination test. The addition of normal plasma adds vWF to the suspension, and in vWD the ristocetin agglutination is corrected. Agglutination with ristocetin requires vWF and GPIb/IX. Since GPIb/IX is absent or reduced in BSS, he ristocetin agglutination is not corrected in BSS, as seen in this patient.3 Flow cytometric analysis of platelet glycoproteins demonstrated reductions in CD42a (GpIX) and CD42b (Gp1bα).

Bernard Soulier syndrome (BSS), also known as Hemorrhagiparous thrombocytic dystrophy, was first described in 1948 as a bleeding disorder characterized by a prolonged bleeding time and giant platelets seen on a peripheral smear. It is an inherited platelet adhesion disorder caused by platelet glycoprotein (GP) deficiencies. The disorder is rare, affecting only about 1 in 1,000,000, though it is more common in families where parents are related. BSS is typically autosomal recessive, though a small number of cases have been found that are autosomal dominant. Most cases are diagnosed at a young age, with the autosomal dominant type often less severe and diagnosed later in life.1

Platelets are involved in primary hemostasis, the initial arrest of bleeding that occurs with vascular injury. As we know, platelets’ functions include adhesion and aggregation. Platelets first stick to the blood vessel wall (adhesion), followed by binding to each other (aggregation). In primary hemostasis, platelets first adhere to von Willebrand factor (vWF) which is bound to the subendothelial collogen fibers. This is followed by aggregation, a complex process that results in the formation of the platelet plug and the initial arrest of bleeding.. In BSS, platelet membrane GPs Ib, V and IX are missing, resulting from an inherited mutation in one of the genes that code for proteins in the complex. This affects the binding of the platelets to vWF, which subsequently interferes with primary hemostatic plug formation.4 If the platelets don’t adhere, aggregation is also affected.

Patient Results

In order to make a differential diagnosis of platelet function disorders, laboratory testing is necessary:

  • Tests of secondary hemostasis, PT and APTT, are normal in this patient so a disorder of primary hemostasis would be suspected.
  • In this patient, the platelet count was slightly decreased. In BSS, the platelet count is variable, from normal is moderately decreased, and can vary from time to time in the same patient.
  • Platelet adhesion tests (PFA) performed with both Col/Epi and Col/ADP were abnormal.
  • Light transmission aggregometry revealed platelet aggregation was normal with ADP, collogen and epinephrine. Aggregation with ristocetin was abnormal.
  • Giant platelets observed on peripheral smear
  • Flow cytometric analysis of platelet glycoproteins demonstrated reductions in CD42a (GpIX) and CD42b (Gp1bα).

Diagnosis: Bernard Soulier syndrome.

Conclusion

BSS is rare and is commonly mistaken for ITP. Reports have been published that analyze cases of BSS patients long treated as ITP. These misdiagnosed cases have been treated with immunoglobulins, steroids, IV anti-D, and other drugs used to treat refractory ITP. Splenectomies have even been reported in some cases. Platelet aggregation to ristocetin and flow cytometry have provided the correct diagnoses. Molecular studies can also be done to identify the abnormal genotype.2 Clues that can lead to a correct diagnosis are childhood ITP that does not spontaneously resolve and does not respond to treatments, other family members with bleeding problems or low platelet counts, platelet counts that are not low enough to explain bleeding or prolonged bleeding times, increased MPV and the presence of giant platelets on the peripheral smear.

This patient was diagnosed with ITP as a child, but treatments did not improve her platelets counts. She continued to have bleeding episodes which increased with the onset of menses. Her grandmother reports a history of bleeding tendencies in other family members. In addition, her parents are related. Her peripheral smears noted giant platelets. Laboratory tests confirmed a diagnosis of BSS.

Bernard Soulier syndrome (BSS) is a rare but important long-term bleeding disorder.

Patients do not require routine prophylactic treatment, so the management of BSS focuses on prophylactic treatment before certain procedures or after injuries. Patients should be advised not to take NSAIDS. The patient should be advised that treatment may be necessary prior to procedures or in response to common bleeding events such as bleeding gums, epistaxis, and menorrhagia. Antifibrinolytic therapy can be used in bleeding episodes. Platelet transfusions are considered for patients before surgery or if anti-fibrinolytics have failed. For severe cases, stem cell transplants have provided a cure. BSS may also be a candidate disorder for gene therapy in the future.1

References

  1. Grainger JD, Thachil J, Will AM. How we treat the platelet glycoprotein defects; Glanzmann thrombasthenia and Bernard Soulier syndrome in children and adults. Br J Haematol. 2018 Sep;182(5):621-632. doi: 10.1111/bjh.15409. Epub 2018 Aug 17. PMID: 30117143.
  2. Reisi N. Bernard-Soulier syndrome or idiopathic thrombocytopenic purpura: A case series. Caspian J Intern Med. 2020;11(1):105-109. doi:10.22088/cjim.11.1.105
  3. Perumal Thiagarajan, MD; Chief Editor: Srikanth Nagalla, MBBS, MS, FACP. https://www.medscape.com/answers/201722-90211/what-is-the-platelet-function-analyzer-100-pfa-100-and-how-is-it-used-in-the-workup-of-platelet-disorders
  4. Turgeon, Mary Louise. Clinical Hematology, Theory and Procedures. Fifth ed. 2012. Lippincott Williams and Wilkens. Baltimore.
Socha-small

-Becky Socha, MS, MLS(ASCP)CMBBCM graduated from Merrimack College in N. Andover, Massachusetts with a BS in Medical Technology and completed her MS in Clinical Laboratory Sciences at the University of Massachusetts, Lowell. She has worked as a Medical Technologist for over 40 years and has taught as an adjunct faculty member at Merrimack College, UMass Lowell and Stevenson University for over 20 years.  She has worked in all areas of the clinical laboratory, but has a special interest in Hematology and Blood Banking. She currently works at Mercy Medical Center in Baltimore, Md. When she’s not busy being a mad scientist, she can be found outside riding her bicycle.

Microbiology Case Study: A 38 Year Old Female with Vaginal Bleeding and Diarrhea

A 38 year old female with history of endometriosis presented to emergency department complaining of heavy vaginal bleeding for 2 weeks duration. She also reported recent diarrhea, abdominal pain, nausea, fatigue, shortness of breath, fever, and chills. On physical exam, the patient had fever, tachycardia, tachypnea, and abdominal distention with a large, 32-week size uterine mass. She was found to have microcytic anemia (Hgb 9.2 g/dL, MCV 77.1 pg), diabetic ketoacidosis (glucose 522 mg/dL, ketones and glucose in urine, A1c 9.1%), and based on the above vital signs and leukocytosis (WBC 31.75/L)met sepsis criteria.

Abdominal CT revealed multiple uterine leiomyomas (fibroids), with the largest measuring up to 13.2 cm and demonstrating characteristics concerning for pyomyoma (abscess arising in  leiomyoma). The patient underwent exploratory laparotomy and myomectomy. Gross images of the resected uterine mass demonstrated  a circumscribed whorled nodular lesion with patchy necrosis (Image 1). Histologic examination of the resected lesion demonstrated a bland smooth muscle tumor, devoid of cytologic atypia and mitotic activity, with area of abscess formation showing necrosis and abundant neutrophils leading to a diagnosis of  “Leiomyoma with severe acute inflammation, areas of necrosis and abscess formation, consistent with pyomyoma (14 cm)” (Image 2).  A tissue Gram stain demonstrates multiple morphotypes of bacteria (image 3). Blood cultures, drawn on admission, flagged positive and the Gram stain revealed gram negative rods and blood, chocolate and Maconkey agars grew creamy gray non-hemolytic colonies that did not ferment lactose.  MALDI-TOF mass spectrometry was performed and identified the isolate as Salmonella species. A triple sugar iron agar slant was set up to confirm the phenotype of a non-typhoidal serovar of Salmonella. Growth of the organism demonstrated abundant hydrogen sulfide production, an acidic butt, and an alkaline slant, confirming the nontyphoidal phenotype.

Image 1. Gross image of the resected leiomyoma (fibroid). Formalin fixed, serially sectioned, encapsulated smooth muscle mass with patchy areas of abscess formation and necrosis. Mass measures 14 cm in greatest dimension.
Image 2. Histopathologic micrograph of hematoxylin and eosin stained leiomyoma (10x objective). A) shows spindle-shaped smooth muscle cells with admixed neutrophils. Central area of necrosis with abscess formation. B) shows edematous and necrotic smooth muscle with intermixed acute inflammation.
Image 3. Tissue Gram stain showing multiple morphotypes of bacilli with poorly staining gram characteristics (40x objective).

Discussion

Pyomyoma, also referred to as suppurative leiomyoma, is an exceedingly rare complication of uterine leiomyoma, which involves infarction of the benign tumor followed by introduction and growth of bacteria.1 Microbes can be introduced by way of ascending genitourinary infection, spread from adjacent structures, or hematogenous or lymphatic spread.2 These infections may be polymicrobial or caused by a single microorganism, and the reported causative agents vary widely, with the most common being Escherichia coli, Staphylococcus species, streptococcal species, enterococcal species, Bacterioides species, Clostridium perfringens, and Candida.3 However, there have been no reported cases of Salmonella species isolated from pyomyoma to date.

Salmonella is a gram negative bacillus belonging to the Enterobacteriacae family.4,5 Salmonella enterica, the species responsible for causing disease in humans, is sub-divided into numerous serovars, which can be broadly grouped into typhoid and nontyphoid.4,5 While the typhoid serovars cause enteric fever, the nontyphoid serovars can cause gastroenteritis and bacteremia.5 Most nontyphoid Salmonella infections are foodborne, and approximately 5% of nontyphoid Salmonella infections progress to bacteremia.4 The bacteria gain access to the bloodstream by utilizing multiple virulence factors to invade the epithelial cells of the gut.4 Salmonella can be identified in the laboratory from blood culture based on several characteristic biochemical results, including Gram stain, absence of lactose fermentation, motility, hydrogen sulfide and gas production, utilization of citrate, and decarboxylation of lysine and ornithine.

This case presents Salmonella species as the cause of sepsis in the setting of pyomyoma, a very rare entity. It is postulated that gastroenteritis caused by nontyphoid Salmonella may have been the cause of the patient’s recent diarrhea, and uncontrolled blood glucose levels in the setting of diabetes may have contributed to the progression to sepsis. We could hypothesize whether the Salmonella seeded the fibroid precipitating the abscess formation since Salmonella is known to cause abscess formation in unusual sites including having a proclivity for vascular sites (e.g., aortitis). The patient unfortunately experienced complications from her sepsis with concomitant surgery. She became unresponsive despite numerous attempts at resuscitation and died.

References

  1. Azimi-Ghomi O and Gradon J. Pyomyoma: Case Report and Comprehensive Literature Review of 75 Cases Since 1945. 2017. SM Journal of Case Reports. 3(4):1054.
  2. Obele, CC, et al. A Case of Pyomyoma following Uterine Fibroid Embolization and a Review of the Literature. 2016. Case Reports in Obstetrics and Gynecology. 2016:9835412.
  3. Iwahashi N, et al. Large Uterine Pyomyoma in a Perimenopausal Female: A Case Report and Review of 50 Reported Cases in the Literature. 2016. Molecular and Clinical Oncology. 5(5):527-531.
  4. Eng SK, et al. Salmonella: A Review on Pathogenesis, Epidemiology, and Antibiotic Resistance. 2014. Frontiers in Life Science. 8(3):284-293.
  5. Coburn B, et al. Salmonella, the Host and Disease: A Brief Review. 2006. Immunology & Cell Biology. 85(2):112-118.

-Heather Jones is a first year AP/CP resident at UT Southwestern.

-Katja Gwin is an Assistant Professor at UT Southwestern in the Department of Pathology and specializes in gynecologic pathology.

-Dominick Cavuoti is a Professor at UT Southwestern in the Department of Pathology and specializes in cytopathology, infectious disease pathology and medical microbiology.

-Clare McCormick-Baw, MD, PhD is an Assistant Professor of Clinical Microbiology at UT Southwestern in Dallas, Texas. She has a passion for teaching about laboratory medicine in general and the best uses of the microbiology lab in particular.

Microbiology Case Study: Blood stream infection in a 77 year old patient – is it Really from Mosquitoes?

A 77 year old male with a past medical history of end stage renal disease (ESRD) on hemodialysis, type 2 diabetes, coronary and peripheral artery disease, and squamous cell carcinoma of the lung on current chemotherapy/radiation was admitted to our hospital from his outpatient hematology oncology clinic for acute hypoxia. Due to an episode of decreased responsiveness and a potential stroke, Head computed tomography (CT) and computed tomography angiography (CTA) were performed. Electroencephalography showed diffuse slowing, suggestive of encephalopathy. Three days after admission, he became hypotensive and febrile. Pulmonology/critical care was consulted; blood and respiratory samples collected for cultures. The blood culture grew gram negative rods in the aerobic bottles (Images 1-3) after overnight incubation. The patient was initially on cefepime and switched to meropenem 500 mg IV daily.

The following day, the blood culture isolate was identified as Elizabethkingia anophelis. The isolate was resistant to both of the patient’s prior inpatient antibiotics, cefepime and meropenem. Additionally, the isolate was resistant to first, second, and third generations of cephalosporins, aztreonam, tetracyclines and tobramycin. However, it was susceptible to amikacin, ciprofloxacin, gentamicin, and trimethoprim/sulfamethoxazole. Meropenem was discontinued and replaced with ciprofloxacin 400 mg IV daily. Infectious disease was consulted; at this time the patient was displaying nuchal rigidity and extreme encephalopathy. Increased dosing of Ciprofloxacin for better central nervous system penetration, in combination with trimethoprim/sulfamethoxazole 2.5mg/kg IV q8h, rifampin 600 mg IV daily was recommended and a lumbar puncture to be performed once the patient was stable. Sadly, due to underlying severe comorbidities, along with worsening CNS responses, the patient expired on day 9.

Image 1. Small gram negative rods of E. anophelis from positive aerobic blood cultures.
Image 2. Blood Agar Plate growing E. anophelis after overnight incubation at 35 degrees C
Image 3: Chocolate plate growing smooth creamy gram negative E. anophelis after overnight incubation at 35 degrees C

Discussion

The genus Elizabethkingia was named after Elizabeth O. King, a microbiologist at the Center for Disease Control (CDC) and Prevention, who discovered many medically important bacteria in the late 1940s to early 1960s. This included describing Elizabethkingia meningoseptica (formerly Chryseobacterium meningosepticum) in 1959. Elizabethkingia and Kingella genera, and the species Kingella kingae are also named in her honor.1 Elizabethkingia is a gram negative, obligate aerobic bacillus. It was classified under the families Flavobacteriaceae and Chryseobacterium, but was reclassified as Elizabethkingia in 2005.2 E. meningoseptica, the most frequently isolated Elizabethkingia species, has been implicated in cases of neonatal sepsis, meningitis, and nosocomial pneumonia.3

On the other hand, E. anophelis was recently characterized in 2011 and was initially thought to be underrepresented likely due to the genotypic and phenotypic similarity to E. meningoseptica.4,5,6 The species name Elizabethkingia anophelis originated from the anopheles mosquito as it has been isolated from the midgut of Anopheles gambiae mosquitoes.4 The role of mosquitos in maintenance and transmission of Elizabethkingia anophelis is unclear.4,6 Oxidase and catalase positive E. anophelis, (Fig 1) grows well on blood and chocolate agar plates (Fig 2 and 3) as smooth and slight-yellowish colonies although it does not grow on MacConkey agar.7

Beginning late 2015, an increased number of Elizabethkingia infections were identified in Southeastern Wisconsin. Between November 2015 to May 2016, 63 cases of E. anophelis were reported to the Wisconsin Division of Public Health. Cases spread across Illinois and Michigan as well, making it the largest E. anophelis outbreak described to date. A case series published from Froedtert Health System hospitals described their experience with E. anopheles.8 This was a retrospective case series of all consecutive patients admitted to Froedtert Health System hospitals with positive cultures of any site for Elizabethkingia, Flavobacterium, and Chryseobacterium from November 2015 to June 2016. In this time period, 11 patients were identified with cultures positive for E. anophelis. All patients had positive blood cultures at the time of hospital admission. E. anophelis was identified in both sterile and nonsterile body fluids. All 11 patients had at least one major comorbidity, including cancer, COPD, diabetes, ESRD requiring hemodialysis, and alcohol abuse. Two patients died within 30 days of a positive E. anopheles culture (attributable mortality rate, 2/11 = 18.2%).5, 8, 9

Interestingly, vertical transmission of E. anopheles causing neonatal meningitis has been reported.6 Molecular evidence suggested vertical transmission from a mother with chorioamnionitis, but a mechanism of colonization for the mother could not be found and environmental contamination was not also found.6,7 On the other hand, taps and aerators contaminated with E. anophelis in an intensive care unit has been reported.10 E. anophelis should be treated as a true pathogen, particularly in patients with multiple comorbidities.8 Isolation in sterile fluid should never be considered a contaminant.

Since Elizabethkingia is a non-glucose, non-lactose-fermenter, the MIC breakpoint of E. anophelis is reported based on those of non-Enterobacterales Table 2B-5 of CLSI (Clinical Laboratory Standard Institute) M100 guidelines. Elizabethkingia species, including E. anophelis, are intrinsically resistant to several antibiotics and produce elevated MIC on in vitro susceptibility tests. A number of species also harbor beta-lactamase/metallo beta-lactamase (MBL) genes. Empirical treatment should include piperacillin/tazobactam plus quinolone, rifampin, or minocycline. Vancomycin has been used in severe infections, especially meningitis. The best duration of therapy has not been evaluated by clinical trials8.

In summary, our patient acquired this infection in the setting of multiple chronic comorbidities and was immunocompromised due to active malignancy and recent chemotherapy. He has a similar clinical profile to the other patients in the above-mentioned study. One notable difference is that our patient’s isolate was resistant to cefepime, where the isolates from this outbreak were susceptible. After discussion with our infectious disease colleagues regarding this case, we agreed his cause of death was likely multifactorial, though this infection may have been a significant contributing factor.

References

  1. KING EO. Studies on a group of previously unclassified bacteria associated with meningitis in infants. Am J Clin Pathol. 1959 Mar;31(3):241-7. doi: 10.1093/ajcp/31.3.241. PMID: 13637033.
  2. Kim KK, Kim MK, Lim JH, Park HY, Lee ST. Transfer of Chryseobacterium meningosepticum and Chryseobacterium miricola to Elizabethkingia gen. nov. as Elizabethkingia meningoseptica comb. nov. and Elizabethkingia miricola comb. nov. Int J Syst Evol Microbiol. 2005 May;55(Pt 3):1287-1293. doi: 10.1099/ijs.0.63541-0. PMID: 15879269.
  3. Jean SS, Lee WS, Chen FL, et al. Elizabethkingia meningoseptica: an important emerging pathogen causing healthcare-associated infections. J Hosp Infect 2014; 86:244–9.
  4. Kämpfer P, Matthews H, Glaeser SP et al. . Elizabethkingia anophelis sp. nov., isolated from the midgut of the mosquito Anopheles gambiae. Int J Syst Evol Microbiol 2011; 61(Pt 11):2670–5. [PubMed] [Google Scholar]
  5. Perrin A, Larsonneur E, Nicholson AC, et al. Evolutionary dynamics and genomic features of the Elizabethkingia anophelis 2015 to 2016 Wisconsin outbreak strain. Nat Commun 2017; 8:15483.
  6. Lau, Susanna K.P.; Wu, Alan K.L.; Teng, Jade L.L.; Tse, Herman; Curreem, Shirly O.T.; Tsui, Stephen K.W.; et al. (February 2015). “Evidence for Elizabethkingia anophelis Transmission from Mother to Infant, Hong Kong”. Emerging Infectious Diseases. 21 (2): 232–241. doi:10.3201/eid2102.140623. PMC4313635. PMID25625669
  7. Koneman’s Color Atlas and Textbook of Diagnostic Microbiology. 7th Edition. 2016.
  8. Castro, C. E., Johnson, C., Williams, M., Vanderslik, A., Graham, M. B., Letzer, D., . . . Munoz-Price, L. S. (2017). Elizabethkingia anophelis: Clinical Experience of an Academic Health System in Southeastern Wisconsin. Open Forum Infectious Diseases, 4(4). doi:10.1093/ofid/ofx251
  9. Wisconsin Department of Health Services; Elizabethkingia 2017. Available at: https://www.dhs.wisconsin.gov/disease/elizabethkingia.htm. Accessed 9 January 2017. [Google Scholar]
  10. Balm MN, Salmon S, Jureen R, Teo C, Mahdi R, Seetoh T, Teo JT, Lin RT, Fisher DA. Bad design, bad practices, bad bugs: frustrations in controlling an outbreak of Elizabethkingia meningoseptica in intensive care units. J Hosp Infect. 2013 Oct;85(2):134-40. doi: 10.1016/j.jhin.2013.05.012. Epub 2013 Aug 17. PMID: 23958153.

-J. Stephen Stalls, MD is a PGY-II pathology resident at the East Carolina University Department of Pathology and Laboratory Medicine. He plans to pursue hematopathology and molecular pathology fellowships, but also greatly enjoys his time in the microbiology lab. Outside of work, he enjoys playing the drums and going to concerts.

-Phyu Thwe, Ph.D., D(ABMM), MLS (ASCP)CM is a Technical Director at Vidant Medical Center Clinical Microbiology Laboratory. She completed a Clinical and Public Health Microbiology Fellowship through a CPEP-accredited program at the University of Texas Medical Branch (UTMB) in Galveston, Texas. She is interested in extrapulmonary tuberculosis and developing diagnostic algorithms.

Hematology Case Study: CBC with >80% Blasts

The patient is a 67 year old male who first visited his dentist at the end of December complaining of pain in the jaw that he had been experiencing since early Dec. He had put off making an appointment because he didn’t want to have to go to the doctor with COVID precautions, but the pain was now radiating to his teeth, so he made a dentist appointment. The dentist found no evidence of abscess or other infection but ‘adjusted his bite’. The patient was advised to take over the counter NSAIDs as needed or pain but no prescriptions was needed. Three weeks later the patient visited an urgent care because he had no improvement of the jaw pain. At this time he relayed symptoms of cough, fever, chills, night sweats and chronic fatigue. Patient history included an active lifestyle with vigorous aerobic exercise several times a week, but the he stated that he had been feeling too fatigued to exercise for over a month. On exam the patient was found to be tachycardic with bilateral tonsillar lymphadenopathy and oropharyngeal exudate. The patient was tested for COVID, influenza and Group A Strep. The COVID-19 was negative, as was the influenza A and B, but the Group A Strep was positive. The patient was sent home with a prescription for antibiotics.

One week later, the patient called his PCP because he still had cough, fever and chills and now was experiencing shortness of breath. The office directed the patient to go to the ER but the patient was reluctant to go to the hospital and stated he would rather be seen at the office. On review of the patients chart, the PCP agreed to see him in the office because he had had a negative COVID test in the past week. Two days later the doctor examined the patient in his office and still suspected COVID-19. He ordered a PCR COVID-19 test along with CBC/differential and erythrocyte sedimentation rate (ESR). We received a routine CBC on the patient. Results are shown below.

The patient had no previous hematology or oncology history and no previous CBC received at our lab. The critical WBC was called to the physician. Based on the WBC and flags on the auto differential, a slide was made and sent to our CellaVision (CV). On opening the slide in CV, we immediately called our pathologist for a pathology review. A rare neutrophil was seen on the peripheral smear, with immature appearing monocytes, few lymphocytes and many blasts.

Image 1. Images from CellaVision.

The pathologist reviewed the slide and the sample was sent for flow cytology studies and FISH. The pathologist’s comment ”Numerous blasts (>60%) consistent with Acute Myeloid Leukemia(AML). Specimen to be submitted for flow cytometry. Hematology consult recommended” was added to the report.

Image 2. Image from CellaVision. Predominately blasts with one neutrophil seen in field of unremarkable RBCs.
Image 3. Image from CellaVision.

The myeloid/lymphoid disorders and acute leukemia analysis by flow cytometry reported myeloblasts positive for CD117,CD33, and CD13. Final interpretation was Acute Myeloid leukemia (non-M3 type).

AML is the most common form of leukemia found in adults. AML was traditionally classified into subtypes M0 through M7, based on the cell line and maturity of the cells. This was determined by how the cells looked under the microscope after a series of special staining techniques, but did not take into account prognosis. It is now known that the subtype of AML is important in helping to determine a patient’s prognosis. In 2016 World Health Organization (WHO) updated the classification system to better address prognostic factors. They divided AML into several broad groups, including AML with certain chromosomal translocations, AML related to previous cancer or cancer therapy, AML with involvement of more than one cell type, and other AML that don’t fall into the first three groups.2 Once a case has been placed in one of these broad groups, the AML can be further classified as poor risk, intermediate risk and better risk based on other test results. Better risk is associated with better response to treatments and longer survival.3 The European LeukemiaNET (ELN) first recommended integrating molecular and cytogenic data into classification to create such a risk classification system for AML in 2010 (ELN-2010). In 2017, this was again revised (ELN-2017) to further improve risk stratification. The ELN-2017 can be used to more accurately predict prognosis in newly diagnosed AML.1

What this means is that AML is now classified by abnormal cell type as well as by the cytogenetic, or chromosome, changes found in the leukemia cells. Certain chromosomal changes can be matched with the morphology of the abnormal cells. These chromosomal changes can help doctors determine the best treatment options for patients because these changes can predict how well treatment will work.

Examples of risk classification include the knowledge that some chromosome rearrangements actually offer a better prognosis. For example, a translocation between chromosomes 15 and 17 [t(15;17)] is associated with acute promyelocytic leukemia (APL or M3). APL is treated differently than other subtypes and has the best prognosis of all the AML subtypes. Other favorable chromosomal changes include [t(8;21)] and [inversion (16) or translocation t(16;16)]. Examples of intermediate risk prognosis are ones associated with normal chromosomes and [t(9;11)]. Poor prognosis is associated with findings such as deletions or extra copies of certain chromosomes or complex changes in many chromosomes.3

The patient was diagnosed with AML, non M3 type. AML prognosis is based on CBC results, markers on the leukemia cells (flow cytometry), chromosome (cytogenic) abnormalities found and gene mutations (molecular abnormalities). In this patient the FISH studies did not demonstrate any chromosome rearrangements, which alone would place him in an intermediate risk group. In addition, our patient was over age 60 and had a WBC over 100,000/mm3 which have both been linked to worse outcomes.

Here’s one more photo for your enjoyment! It’s not often that we see so many blasts in a patient with no previous history. As a side note, I was contemplating titling this blog “Fatigue and Shortness of Breath in the Time of COVID.” I can’t help but wonder if this patient would have been diagnosed 6-8 weeks earlier if this was another year and he had been seen when he first experienced symptoms. This year, emergency rooms and physicians have reported a decrease in numbers of patients being seen for chest pain, ketoacidosis, shortness of breath, strokes and other serious conditions. Many patients are reluctant or afraid of sitting in crowded waiting rooms, fearful they will catch COVID. And many doctors are only offering virtual visits or have reduced the number of patients being seen so it is harder to get appointments. This patient expressed his reluctance to seek medical help because of fears of COVID. He did not want to go out in public and waited almost a month for symptoms to go away on their own before first being seen. After going to the walk in center, he called his PCP a week later and was still averse to going to the ER as suggested by the doctor. Then he waited another 2 days for an office appointment. The doctor still suspected COVID, but fortunately for the patient, ordered a CBC. The flow cytometry and FISH studies were available the following day. The patient was referred for hematology consult but has not been seen again at our hospital.

Image 4. More images from CellaVision.

References

  1. Boddu, P.C., Kadia, T.M., Garcia‐Manero, G., Cortes, J., Alfayez, M., Borthakur, G., Konopleva, M., Jabbour, E.J., Daver, N.G., DiNardo, C.D., Naqvi, K., Yilmaz, M., Short, N.J., Pierce, S., Kantarjian, H.M. and Ravandi, F. (2019), Validation of the 2017 European LeukemiaNet classification for acute myeloid leukemia with NPM1 and FLT3‐internal tandem duplication genotypes. Cancer, 125: 1091-1100. https://doi.org/10.1002/cncr.31885
  2. Mandel, Ananya. Acute Myeloid Leukemia Classification. Medical Life Sciences. https://www.news-medical.net/health/Acute-Myeloid-Leukemia-Classification.aspx
  3. Ari VanderWalde, MD, MPH, MA, FACP; Chief Editor: Karl S Roth, MD. Genetics of Acute Myeloid Leukemia. Medscape. Updated: Dec 17, 2018 
Socha-small

-Becky Socha, MS, MLS(ASCP)CMBBCM graduated from Merrimack College in N. Andover, Massachusetts with a BS in Medical Technology and completed her MS in Clinical Laboratory Sciences at the University of Massachusetts, Lowell. She has worked as a Medical Technologist for over 40 years and has taught as an adjunct faculty member at Merrimack College, UMass Lowell and Stevenson University for over 20 years.  She has worked in all areas of the clinical laboratory, but has a special interest in Hematology and Blood Banking. She currently works at Mercy Medical Center in Baltimore, Md. When she’s not busy being a mad scientist, she can be found outside riding her bicycle.