Microbiology Case Study: A 65 Year Old Man with Pneumonia

Case History

A 65 year old male with a history of systolic heart failure secondary to non-ischemic (alcohol-induced) dilated cardiomyopathy underwent cardiac transplantation on 10/11/2016. He was hospitalized between 3/1/17 and 4/15/17 for neutropenia and CMV viremia. Two days after discharge, he presented to the hospital with a gradual-onset of left-sided sharp chest pain described as “soreness” over his rib cage and exacerbated by breathing. Associated symptoms included fever, malaise, and fatigue. In the emergency department, vital signs included: BP 144/75 mmHg, T 40.2°C, RR 24/min, HR 101 bpm, SpO2 97% on room air. A CBC revealed a normal white blood cell count and a chest X-ray demonstrated a lingular opacity. The immunocompromised patient was admitted for sepsis secondary to presumed pneumonia following recent hospitalization. He was treated empirically for hospital-acquired pneumonia with vancomycin and piperacillin-tazobactam. After a urine antigen test detected the presence of Legionella pneumophila serogroup 1, antibiotic treatment was changed to levofloxacin and an induced sputum culture was obtained for Legionella surveillance.

legion1
Image 1. Sputum culture on BCYE agar with PAV shows Legionella pneumophila colonies that are circular with smooth edges, grey-white, and glistening in addition to few usual oropharyngeal flora.

Discussion

Legionnaires’ disease, caused by Legionella bacteria, is a cause of 1-9% of both community-acquired and hospital-acquired pneumonias. Symptoms of fever, chills, cough, and chest pain are similar to other causes of pneumonia; however multiple organ systems may be involved, producing additional symptoms including gastrointestinal (diarrhea, nausea, and vomiting) and central nervous system (headache and confusion) findings. Legionella was first discovered after a 1976 outbreak of pneumonia among Pennsylvania State American Legion members who attended a convention at a Philadelphia hotel that had infected water in the air conditioning system; it is reported that 29 out of 182 infected people died. At present, the mortality rate of Legionnaires’ disease ranges from less than 10% in treated community-acquired cases to approximately 30% for hospital-acquired cases.

The genus Legionella contains greater than 60 species of which approximately 20 are human pathogens. Legionella pneumophila (consisting of serogroups 1-16) is the most common cause of Legionnaires’ disease and, in particular, L. pneumophila serogroup 1 causes 70-90% of cases. The organisms are ubiquitous in nature, particularly in warm freshwater environments including lakes and streams, where they infect and multiply within single-celled host organisms. Of pathogenic concern, they can be present in high numbers in human-made complex water systems (such as cooling towers, whirlpool spas, humidifiers, and decorative fountains). After environmental aerosols are inhaled or contaminated water is aspirated into the lungs, alveolar macrophages are infected by the obligate intracellular bacteria. Host risk factors for developing Legionnaires’ disease include organ transplantation, immunocompromised state, immunosuppresion, age greater than 60 years, chronic lung disease, and smoking.

In the microbiology laboratory, Legionella are mesophilic (20-45 °C) obligate aerobes. The small, thin gram negative rods react poorly with Gram stains and are not usually stained in direct clinical samples. The patient’s Gram smear revealed moderate neutrophils, few squamous epithelial cells, and mixed gram positive and gram negative organisms present. Sensitivity for detecting the biochemically inert and fastidious bacteria is increased with culture on buffered charcoal yeast extract (BCYE) agar. For sputum samples that are likely contaminated with usual oropharyngeal flora, BCYE agar with polymyxin B, anisomycin, and vancomycin (PAV) media are used. After 3-5 days of incubation, Legionella colonies appear convex, circular, 3-4 mm in diameter, grey-white to blue-green, and glistening. This identification was confirmed by MALDI-TOF MS. Laboratory in vitro susceptibility studies are not recommended on individual isolates, as they do not correlate with clinical responses. Monotherapy with a fluoroquinolone (Levofloxacin) or macrolide (Azithromycin) is active against Legionella.

 

-Adina Bodolan, MD is a 1st year anatomic and clinical pathology resident at the University of Vermont Medical Center.

Wojewoda-small

-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.

Help! OSHA is in My Lab!

Hospitals and other healthcare facilities have been on OSHA’s “high-risk” workplace list for a few years. That means the regulatory agency has noticed an increased number of employee injuries there, and therefore OSHA inspections have increased in hospitals and labs as well. If an OSHA inspector arrives at your facility, you should not panic, but you should know some very specific steps to follow.

If inspectors come directly to your department and you belong to a hospital or larger facility, be sure to contact your administration and accreditation departments immediately. This is a government agency on site, and the facility representatives need to be aware and involved. Verify the identity of the inspector(s). Sadly, there are imposters who pose as inspectors for the purpose of collecting money. OSHA inspectors will never talk about fine amounts during an inspection, and they certainly would not collect money on site. To prove the inspectors’ identity contact the state or federal OSHA office and verify that an inspector is scheduled to be on site. Twenty seven U.S. states and territories operate OSHA-approved State Plans, and if that is true in your area, it will be the state inspector on site rather than someone from the federal government.

OSHA is legally authorized to conduct workplace inspections to enforce health and safety standards, so it is usually best to allow them to inspect if requested. That said, you do have the right to require the inspector to obtain a search warrant before allowing them into your lab. However, as you can imagine, this will give an inspector the wrong idea about what you may or may not be hiding. They may dig deeper when they do return with that warrant, so it may not be the best course of action to turn them away.

An OSHA inspection begins with an opening conference which details the scope and purpose of the inspection. In the initial meeting, it is acceptable to ask the purpose of the inspection and its anticipated length. Ask what documents the inspector will want to see, and ask if there are any specific employees he or she will need to interview. If the inspection was triggered by an employee complaint, ask for a copy of the written report. The inspector may review certain lab documents pertinent to the investigation, and these may include the chemical hygiene plan, exposure control plan, or other policies and procedures.

While on site, the OSHA inspector should always be accompanied by a representative of your employer, an escort, and their next steps will usually be a walk-through of the inspected areas to look for safety hazards and to talk to employees. The inspector may talk to staff, take notes, and take pictures. The lab escort should take copious notes while this is happening, and it is advisable to take pictures of whatever the inspector documents with photographs.

If the inspector asks to interview an employee, he may do so in private so long as the employee agrees to that. Train staff to never volunteer information during an OSHA inspection; they should answer only what is asked. An OSHA inspector may ask if the employee familiar with lab safety policies and procedures, and whether or not the employee follows those procedures. They will try to determine if staff is aware of hazards in the workplace. If the inspector points out safety violations he notes, do not agree to them; it may be taken as an admission of wrong-doing and could incur a fine. If you are able to correct the violation on site, do so immediately, but understand that you could still be cited. However, this goes a long way toward showing the inspector that your interest truly is in cooperating and keeping employees safe.

Once the investigation is complete, the inspector will hold a closing session on site. During that time the lab will be notified about citations that will appear in the written report. The inspector will explain your right to appeal noted violations and give information on how and by when to appeal. They will answer any questions you may have. If on-site corrections were allowed during the inspection, be sure the inspector states that the follow up was completed.

If a citation will be incurred, start right away to prepare your response while the information is fresh in your mind. An OSHA report can take up to six months to be sent to the facility. Post OSHA citations at or near the site of the violation in the department.  If the correction of the violation takes longer than three days, the posting must remain until the correction is completed. After correcting a hazard, notify OSHA in writing. Employers have up to 25 days to submit OSHA an abatement of the safety issue or issues. If the abatement will take a long time (greater than 90 days), the first abatement progress report is due to OSHA within 55 days.

OSHA fines increased in 2016 for the first time in over 30 years. A single fine amount can range from $12,500 up to $125,000 depending on the seriousness of the violation. That’s just one reason to make sure your lab is following OSHA safety regulations. Keep your staff safe, but if OSHA knocks on your door, remain calm, and follow the steps to ensure a smooth inspection and follow-up process.

 

 

Scungio 1

Dan Scungio, MT(ASCP), SLS, CQA (ASQ) has over 25 years experience as a certified medical technologist. Today he is the Laboratory Safety Officer for Sentara Healthcare, a system of seven hospitals and over 20 laboratories and draw sites in the Tidewater area of Virginia. He is also known as Dan the Lab Safety Man, a lab safety consultant, educator, and trainer.

The Challenges of Clinical Laboratories in Developing Countries

Achieving and maintaining quality is arguably one of the most critical tasks in clinical laboratories. Without a proper quality, clinical laboratories are essentially unsafe for patients. Poor quality results can cause mistrust between laboratories and end users, and therefore, endangers the practice of evidence-based medicine and precludes viable engagements between clinicians and laboratorians. Furthermore, poor quality clinical laboratories can hinder global efforts to fight infectious diseases and outbreaks (1).

Ensuring quality is a journey without a destination. It demands constant attention and continuous active participation of all involved in the testing processes. For example, the majority of testing transactions are mediated by clinicians. Their direct involvement in the testing processes makes them inevitable partners in ensuring quality. Thus, close cooperation and constructive engagement with clinicians is critical for laboratorians to provide sustainable quality service. However, ensuring quality can be laborious as it includes coordination with multiple bodies that are not conventional members of clinical laboratories.

The quality of most clinical laboratories in most developing countries is poor.  For example, most clinical laboratories in Africa do not meet international standards (2, 3). Why? There are several factors that contribute to this occurrence but the answer distills into the following: Lack of adequate resources, proper regulations, and supportive health care system.

Lack of adequate resources

The contributions of laboratorians in the diagnosis and management of diseases are generally under-recognized. Laboratorians in developing countries are no exception, if not worse. The lack of recognition compounded by inadequate compensation often leads to job dissatisfaction, negligence, lack of interest, and as a result, departure from the profession. The worst consequence of this phenomenon is over time depletion of qualified personnel, seeking for better opportunities elsewhere. While it is indisputable that developing countries face acute resource limitations, it is not necessarily due to lack of funding but also due to resource misappropriation, improper governance, and rampant corruption.

Lack of proper regulations

The notion that no result is better than poor quality result underscores the critical importance of quality in clinical laboratories. However, it is usually difficult to maintain quality without imposing proper regulatory requirements and enforcing strict regulations. For example, a survey conducted in clinical laboratories in Kampala, Uganda, reveals that most clinical laboratories do not meet international standards (1). Most clinical laboratories in Africa are not accredited (2). Most of the laboratories are not enrolled in external assurance programs; those enrolled do not necessarily adhere to strict follow-ups. These kinds of problems can be averted, at least in part, by introducing stringent regulatory requirements and enforcing the regulations to the details.

Lack of adequate support

Clinical laboratories in developing countries suffer inadvertent neglect and are not well-supported to ensure accurate diagnosis. The healthcare system in developing countries perceives clinical laboratories as “tools” rather than “partners” in the disease diagnosis processes. This kind of unfortunate perception is inherently flawed because clinical laboratories are indeed critical in diagnosing diseases, curbing outbreaks, addressing growing global health concerns. In that sense, laboratories and laboratorians should be deemed and treated as partners.  This is an important distinction to make because partnership fosters collaboration, respect, and recognition, encourages horizontal communications between laboratorians and clinicians, and helps garner support from clinicians, the public, and policymakers.

In summary, the majority of treatment decisions in developing countries are based on clinical judgment and empiric diagnosis (4). Because access to reliable diagnostic testing is limited or undervalued, misdiagnosis commonly occurs, resulting in inadequate treatment, increased mortality, and an inability to determine the true prevalence of diseases. Furthermore, mistrust is rampant due to poor quality results and consequently, viable engagements between the clinical laboratories and clinicians are often impaired.

Laboratorians in developing countries should set up efficient professional societies, enhance communication and diplomacy with clinicians and policymakers, and foster collaborative environment towards achieving continuous quality improvement. Strong and viable societies should then advocate for the wellbeing of clinical laboratories and laboratorians in developing countries. Furthermore, any effort from the global health community should first be directed to identifying and targeting fundamental problems in partnership with local professionals and authorities.

References

  1. Berkelman R, Cassell G, Specter S, Hamburg M, Klugman K. The “Achilles heel” Of global efforts to combat infectious diseases. Clin infect dis, Vol. 42. United States, 2006:1503-4.
  2. Schroeder LF, Amukele T. Medical laboratories in sub-saharan africa that meet international quality standards. Am J Clin Pathol 2014;141:791-5.
  3. Elbireer AM, Jackson JB, Sendagire H, Opio A, Bagenda D, Amukele TK. The good, the bad, and the unknown: Quality of clinical laboratories in kampala, uganda. PLoS One 2013;8:e64661.
  4. Petti CA, Polage CR, Quinn TC, Ronald AR, Sande MA. Laboratory medicine in africa: A barrier to effective health care. Clin Infect Dis 2006;42:377-82.

 

Tesfazghi_small

-Merih T Tesfazghi, PhD, is a Clinical Chemistry Fellow with the Department of Pathology and Immunology at Washington University School of Medicine in St. Louis, MO.

Microbiology Case Study: A 24 Year Old Refugee with Eye Irritation

Case History

A twenty-four year-old male Kenyan refugee had been in the United States for about a month when he received a mandatory health screen for infectious diseases. He had no complaints and stated that overall, he was generally healthy. Physical exam was significant only for bilateral red conjunctiva. He stated at times his eyes get irritated and have since birth. As part of routine work-up, an ova and parasite stool exam was ordered. Organisms were detected as seen in Image 1.

giardia1
Image 1. Trichrome stained slides of patient’s stool sample.

 

Discussion

The patient’s stool examination showed Giardia cysts. Two nuclei are visible in the figure above with centrally located karyosomes. Also visible are the intracytoplasmic fibrils, seen as a darker purple area.

Giardia is a flagellated protozoan that causes giardiasis, a diarrheal illness. It is the most commonly diagnosed intestinal parasitic disease in the United States. It is known as Giardia intestinalis, Giardia lamblia, or Giardia duodenalis. The most common mode of transmission is drinking water contaminated with feces from infected mammals (1).

Symptoms vary and can last 1 week to years if untreated (2). Typical symptoms of giardia are “greasy, foul-smelling, frothy stools that float.” Interestingly, less common symptoms can be itchy skin, hives, eye and joint swelling (3). Retinal arteritis and iridocyclitis has been noted as well (4). It is possible that this patient’s eye irritation is due to a chronic giardiasis infection. Common treatment is usually with an antibiotic/antiparasitic drug like metronidazole (Flagyl).

Diagnosis of Giardia can be made by demonstrating the pear shaped trophozoites and/or ovoid cysts in feces. A key identifier for this parasite is the presence of the two to four nuclei with a central karyosome and intracytoplasmic fibrils that make the parasite look like a face under the microscope. However, because Giardia is excreted intermittently, it is recommended to sample three stool specimens on separate days (5). Due to problems in concentrating the organism for identification on a trichrome stain, a fecal immunoassay is available that is more sensitive and specific (5).

References

  1. https://www.cdc.gov/parasites/giardia/index.html
  2. Robertson LJ, Hanevik K, Escobedo AA, Mørch K, Langeland N. Giardiasis–why do the symptoms sometimes never stop?. Trends Parasitol. 2010;26(2):75-82.
  3. https://www.cdc.gov/parasites/giardia/illness.html#seven
  4. Wolfe MS. Giardiasis.[PDF – 8 pages] Clin Microbiol Rev. 1992;5(1):93-100
  5. https://www.cdc.gov/parasites/giardia/diagnosis.html

 

-Angela Theiss is a pathology resident at the University of Vermont Medical Center.

Wojewoda-small

-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.

Pathologist on Call: There Is No Perfect Lab Test for Smoking Assessment

Cigarette smoking can affect both innate and adaptive immunity, and introduces concerns when evaluating a patient’s eligibility for surgery. It has been shown to hinder time required for healing and long-term survival of patients. It can promote vascular complications, increase the rates of hepatocellular carcinoma and reduce lung function.1 For lung transplantation, one of the common requirements of eligibility is smoking abstinence for at least 6 months. Smoking post-surgery is associated with worse outcomes for the patients including complications and higher rates of mortality.2 Relapse to smoking post lung transplantation has been reported to range from 11% to 23% in various patient populations.3 As a result, clinical testing for cigarette smoking abstinence is an important part of initial workup and follow-up of transplant patients.

In some situations, the burden of lung allocation weighs heavily on a single clinical laboratory result that is perceived to definitively confirm or exclude active cigarette smoking. This subsequently factors into the decision by the physicians to deem the patient eligible to receive a lung transplant. The perception of nicotine testing as definitive proof of smoking is misleading and does not reflect the complexity of situations that can lead to a positive test result.

How can we assess smoking?

Ideally, many factors should weigh into the final smoking status determination including self-reporting (used historically), witnesses to behavior, odor, and past history including cessation attempts. Clinical laboratory testing is important and thought to be more reliable means for smoking assessment. It can involve testing for nicotine (originating from tobacco or nicotine replacement therapy, NRT) and its metabolites: cotinine, 3-hydroxycotinine (3-OH-cotinine), and nornicotine. Moreover, nicotine contains a number of alkaloids that are not usually present in nicotine-replacement therapies (NRTs) including anatabine and anabasine.4 Nicotine testing can involve a combination of metabolites such as cotinine as well as alkaloids like anabasine. Various sample types have been used including saliva, blood and urine.5 In addition, measurements of the exhaled carbon monoxide (CO) have been used to assess recent smoking status (within the last 8 hours).6

Clinical case: patient with detectable nicotine metabolites

A case involving a patient being considered for lung transplantation was received by our department. The patient had been tested for anabasine, nicotine, and its metabolites in urine. Testing of random urine specimens was performed by liquid chromatography tandem mass spectrometry (LC-MS/MS) at different time points from samples collected during hospital visits (days 0, 38, and 62). The urine contained variable concentrations of nicotine and its metabolites, with anabasine concentrations below the detection limit in 2 out of the 3 testing instances. Testing at day 0 showed an interfering substance that prevented the determination of accurate anabasine concentration. The nicotine and its metabolite concentrations in the random urine specimens were lower from day 0 to day 38, but a noticeable increase of 3-OH-cotinine and cotinine concentrations was observed in the specimen collected on day 62. The physician was seeking information about the current smoking status of the patient and was planning to use this information to determine the patient’s lung transplant eligibility.

smoking-1

 

Days 0 38 62
Analyte concentration (ng/mL)
3-OH-cotinine 4074 89 603
Anabasine interf. subst. < 3 < 3
Cotinine 1404 47 425
Nicotine 241 < 2 72
Nornicotine 58 < 2 6

 

Figure and table 1. Nicotine, metabolite and anabasine concentrations (ng/mL) at different time points for a patient evaluated for lung transplantation eligibility. Anabasine was not detected on days 38 and 62, with an interfering substance preventing quantitation on day 0.

How definitive are these results?

No information was available regarding self-reported smoking or NRT use history for this patient. The physician had high suspicion that the patient was an active smoker and was attempting to use higher concentrations of nicotine and metabolites observed on day 62 as evidence of recent tobacco use.

For cotinine, values can range from 20-550 ng/mL for daily tobacco use.5 Nicotine concentrations in urine can approach over 5000 ng/mL with daily use. Together, high nicotine and cotinine can support tobacco or high-dose nicotine patch use. Furthermore, presence of nornicotine above 30 ng/mL along with anabasine greater than 10 ng/mL would be consistent with current tobacco use rather than NRT.7

Given that these were random urine specimen and the urinary creatinine values are not routinely measured, it’s important to consider the possible contributions of the variable urine concentration to the analyte concentrations. It has previously been reported that individuals abstaining from smoking for at least two weeks should present with nicotine of <30 ng/mL, cotinine of < 23 ng/mL, 3-OH-cotinine of <120 ng/mL, nornicotine < 3 ng/mL, and anabasine of < 2 ng/mL in urine.7 Based on these cut-offs, all analytes except anabasine would suggest new nicotine intake within the last two weeks.

In general, a positive anabasine result, in combination with the presence of nicotine metabolites, is consistent with active use of a tobacco product, whereas anabasine values of < 2ng/mL may suggest that NRT is the likely source.8 This can imply that the patient is abstinent from smoked or chewed tobacco if anabasine is not detected. However, anabasine is not a sensitive marker of smoked tobacco. It has been reported that the compound may not be detectable in 60% of self-reported smokers (N=51; 3 ng/mL cut-off in urine)9  and its urinary concentrations do not correlate well with self-reported tobacco use.8

As a result, anabasine has low sensitivity for determining eligibility for UNOS (United network for organ sharing) listing. There are some recommendations that this marker should not be used alone. Given that other alkaloids can originate from tobacco plant, it has been proposed that anatabine should be added to analysis due to higher expected concentration.9 However, this alkaloid is not completely specific to tobacco as it has been proposed to also arise from other plant sources 10,11  leading to possible implications for the patient that may be misclassified. In addition, anatabine sensitivity in detecting smoked tobacco use varies depending on the tobacco source and the clinical cut-off used. Clinical tests that include anatabine are not routinely available.

Can we improve this process?

Unfortunately, there is no definitive marker distinguishing smoking from NRT.

The determination of smoking status has advanced from reliance on self-reporting to quantitative and specific measurements of metabolites of nicotine and minor components of tobacco. Additional analyte incorporation into a test panel leads to additional complexities and considerations in interpretation of the results. Therefore, it is important to educate the physicians about various nicotine sources causing a positive nicotine and/or metabolite test result including NRT or e-cigarettes. It is also important to convey the limitations of tobacco alkaloid testing in such scenarios. Both the lab and the physician need to be cautious about implying active smoking in the absence of indirect supporting evidence and/or positive clinical test results.

At the same time, there is a need to improve the utility and availability of other tobacco alkaloid testing in distinguishing cigarette smoking from NRT in specific transplant populations and consider the value of testing alternative specimens. This may lead to a more effective implementation of secondary markers of tobacco use.

References

  1. Qiu, F.; Fan, P.; Nie, G. D.; Liu, H.; Liang, C.-L.; Yu, W.; Dai, Z., Effects of Cigarette Smoking on Transplant Survival: Extending or Shortening It? Frontiers in Immunology 2017, 8, 127.
  2. Zmeskal, M.; Kralikova, E.; Kurcova, I.; Pafko, P.; Lischke, R.; Fila, L.; Valentova Bartakova, L.; Fraser, K., Continued Smoking in Lung Transplant Patients: A Cross Sectional Survey. Zdravstveno varstvo 2016, 55 (1), 29-35.
  3. Vos, R.; De Vusser, K.; Schaevers, V.; Schoonis, A.; Lemaigre, V.; Dobbels, F.; Desmet, K.; Vanaudenaerde, B. M.; Van Raemdonck, D. E.; Dupont, L. J.; Verleden, G. M., Smoking resumption after lung transplantation: a sobering truth. The European respiratory journal 2010, 35 (6), 1411-3.
  4. Hukkanen, J.; Jacob, P., 3rd; Benowitz, N. L., Metabolism and disposition kinetics of nicotine. Pharmacological reviews 2005, 57 (1), 79-115.
  5. Raja, M.; Garg, A.; Yadav, P.; Jha, K.; Handa, S., Diagnostic Methods for Detection of Cotinine Level in Tobacco Users: A Review. Journal of clinical and diagnostic research : JCDR 2016, 10 (3), Ze04-6.
  6. Sandberg, A.; Skold, C. M.; Grunewald, J.; Eklund, A.; Wheelock, A. M., Assessing recent smoking status by measuring exhaled carbon monoxide levels. PloS one 2011, 6 (12), e28864.
  7. Moyer, T. P.; Charlson, J. R.; Enger, R. J.; Dale, L. C.; Ebbert, J. O.; Schroeder, D. R.; Hurt, R. D., Simultaneous analysis of nicotine, nicotine metabolites, and tobacco alkaloids in serum or urine by tandem mass spectrometry, with clinically relevant metabolic profiles. Clinical chemistry 2002, 48 (9), 1460-71.
  8. Jacob, P., 3rd; Hatsukami, D.; Severson, H.; Hall, S.; Yu, L.; Benowitz, N. L., Anabasine and anatabine as biomarkers for tobacco use during nicotine replacement therapy. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology 2002, 11 (12), 1668-73.
  9. Feldhammer, M.; Ritchie, J. C., Anabasine Is a Poor Marker for Determining Smoking Status of Transplant Patients. Clinical chemistry 2017, 63 (2), 604-606.
  10. Lanier, R. K.; Gibson, K. D.; Cohen, A. E.; Varga, M., Effects of dietary supplementation with the solanaceae plant alkaloid anatabine on joint pain and stiffness: results from an internet-based survey study. Clinical medicine insights. Arthritis and musculoskeletal disorders 2013, 6, 73-84.
  11. von Weymarn, L. B.; Thomson, N. M.; Donny, E. C.; Hatsukami, D. K.; Murphy, S. E., Quantitation of the minor tobacco alkaloids nornicotine, anatabine, and anabasine in smokers’ urine by high throughput liquid chromatography mass spectrometry. Chemical research in toxicology 2016, 29 (3), 390-397.

 

VG

-Dr. Valentinas Gruzdys developed interest in clinical chemistry early in his academic training which led him to pursue and obtain a PhD in Clinical and Bioanalytical Chemistry at Cleveland State University. Valentinas is enthusiastic about teaching and helping improve the understanding of limitations and utility of clinical laboratory testing. He is currently enrolled in a clinical chemistry fellowship program at the University of Utah. He enjoys learning more about various aspects of clinical chemistry and cannot wait to make his own contributions to the field after his training.

Microbiology Case Study: A 10 Year Old Boy with Right Knee Pain

Case History  

A 10 year old Caucasian male presented to the pediatric emergency department due to significant pain in his right knee with exposed hardware. His past medical history was noteworthy for Perthe’s Disease, a condition leading to avascular necrosis of the femoral head. In addition, he is affected by an autosomal dominant congenital disorder and has had ischemic strokes in the past. Recently, he had surgery performed on multiple joints to correct abnormalities and they were complicated by dehiscence & infection with methicillin sensitive Staphylococcus aureus. On current admission, his mother reported he has been afebrile and was consistently taking cephalexin to treat the above infection. He was taken to the operating room for incision & drainage and hardware removal of the knee. Bacterial cultures were collected at the time of surgery and he was started on IV clindamycin.

Laboratory Identification

eikcor1
 Image 1. Clear, spreading colonies that showed “pitting” of the agar after 48 hours incubation at 37°C in 5% CO2.  
eikcor2
Image 2. Gram stain directly from the colony showed slender gram negative rods (100x oil immersion).

On direct Gram stain, there was no organisms seen and rare white blood cells. Initially, there was no growth at 24 hours, but two morphologies were observed on the second day. The first organism was identified as the S. aureus that was previously isolated from this site. The second organism was clear with spreading colonies that pitted the agar (Image 1). A distinct bleach like odor was observed. There was no growth on MacConkey agar even though the Gram stain showed gram negative rods, making this organism most likely to be classified as fastidious (Image 2). Benchtop biochemical tests were negative for catalase and positive for oxidase. MALDI-TOF mass spectrometry identified the isolate as Eikenella corrodens. 

Discussion

Eikenella corrodens is a fastidious Gram negative rod that is a member of the HACEK family. It is considered normal flora in the oral cavity and possibly the gastrointestinal tract of humans.  Infection results from these endogenous sources and can be the result of poor oral hygiene, mucositis or dental procedures. E. corrodens causes juvenile and adult periodontitis and is commonly implicated in bacteremia and infective endocarditis, particularly in IV drug users who lick needles prior to injection. Infections of the abdomen, bones/joints and brain are less common.

In the laboratory, E. corrodens is slow growing and is usually present as clear, spreading colonies after 48 hours incubation at 37°C in 5% CO2 on blood and chocolate agars. A unique feature of the organism is that it pits or corrodes the agar, lending to its species name. Also, E. corrodens produces a bleachy smell due to the production of hypochlorite. It does not grow on MacConkey agar despite the fact it is a Gram negative rod. Biochemical tests are negative for catalase, positive for oxidase and negative for indole. Automated instruments and MALDI-TOF mass spectrometry are both able to identify E. corrodens with confidence.

Susceptibility guidelines can be found in the 3rd edition of the CLSI M45 document. In general, E. corrodens is susceptible to penicillin, board spectrum cephalosporins, carbapenems, azithromycin and fluoroquinolones. Resistance to narrow spectrum cephalosporins, macrolides and clindamycin has been documented. In general, susceptibility testing should be performed on E. corrodens when it is isolated from a normally sterile site or is identified in pure culture. Beta lactamase testing is recommended routinely on E. corrodens, and if positive, the isolate is resistant to penicillin, ampicillin and amoxicillin. In the case of bite wounds caused by E. corrodens, susceptibility testing may not be necessary if it is treated with amoxicillin-clavulanate acid (Augmentin) due to a high probability of susceptibility to this antibiotic.

In the case of our patient, he responded to the antibiotic therapy used to treat his S. aureus and E. corrodens infections and healed well. He was placed on long term oral antibiotic therapy until additional hardware is able to be removed at a future date.
RA

-Rim Alkawas, MD, is a first year Anatomic and Clinical Pathology resident at the University of Mississippi Medical Center. 

Stempak

-Lisa Stempak, MD, is an Assistant Professor of Pathology at the University of Mississippi Medical Center in Jackson, MS. She is certified by the American Board of Pathology in Anatomic and Clinical Pathology as well as Medical Microbiology. She is the director of the Microbiology and Serology Laboratories. Her interests include infectious disease histology, process and quality improvement and resident education.

Boards and Wards

As a little detour before I start my medical school clerkship rotations as a 3rd year student, I’d like to take a moment to appreciate—yes appreciate—board exams. I just sat for the daunting and arduous United States Medical Licensing Exam (USMLE) called “Step 1.” It is roughly an eight-hour endeavor to prove that some of the tomes of information I was exposed to throughout my first two years of medical school made it somewhere into my hippocampus. That said, yes board exams are always daunting and yes, they can even be quite stressful. There’s a lot depending on your scores, in any field you find yourself testing in. Some are pass/fail and some provide you with a scaled score performance.

For what feels like forever ago to me now, I sat for a state licensure exam for the Illinois Department of Public Health as an Emergency Medical Technician Basic provider, or EMT-B. I absolutely failed it—missed it by a point or so. Scheduled a retake, studied hard, and passed round two. Lesson learned. That license opened many doors for me back in the day, and that’s precisely the point: professional certification, official licensures, and (often) professional society membership will bolster anyone looking to get ahead in their career.

Other times, these board exams are highly encouraged. After graduate school at Rush for my MLS degree I had to sit for the ASCP BOC Board Exam for the professional credentials of a Medical Laboratory Scientist, or MLS (ASCP). When I passed, I was able to advance in my career then and have excellent opportunities that would be unavailable otherwise. More so, certain jobs would have been completely unavailable to me without those clinical credentials! I would say that like ASCP cites 70% of patient results originate from the lab, 70% of my CV depends on those professional credentials.

aki-fig-1
Figure 1. A previously renewed ASCP BOC certificate, proudly displayed.

This brings up a somewhat related point. There is a professional debate that’s been going on for a few years: board certification vs. regulatory licensure. Organizations like ASCP and CAP have been on board with licensure for a while, citing the critical roles we play in patient care and the specialized education training required. An article from 2015 had circulated well explaining the advantages and regulatory compliance improvement offered by licensure as medical laboratory science evolved since the Clinical Laboratory Improvement Act of 1988 (known as CLIA ’88). Those authors established that virtually all laboratory professional organizations, as well as local state public health departments, favor licensure to guarantee regulatory oversight for the quality of personal and testing results (Rohde et al., 2015). With so many questions today about what qualifies laboratory personnel since the Center for Medicaid Services decision in 2016 that says a bachelor’s degree in nursing is sufficient to perform and manage laboratory moderate to complex testing, professional organizations like ASCP, CAP, and ASCLS continue to investigate what measures would maintain quality and regulations for positive patient outcomes.

aki-fig-2
Figure 2. States with licensure, and without. I was trained and practiced medical laboratory science in Chicago, Illinois, a state that does not require licensure. (Rohde et al., 2015)
aki-fig-3
Figure 3. These graphs show the number of sanctions under CLIA imposed on labs in the following states. This demonstrates the ineffectiveness of CLIA improving laboratory testing or personnel quality. (Rohde et al., 2015)

Like the EMS exam, the USMLE is absolutely mandatory if I in any capacity wish to continue my medical education, match into a residency program, and ultimately practice as a physician. So, as daunting as these tests might be, they provide a good benchmark standard for the quality of physicians from around the world who want to practice in the United States. USMLE actually has a series of four board exams I’ll be taking in the coming years—so bear with me as I try to stay positive. The Step exams check the depth and breadth of one’s understanding of medical concepts from anatomy to the minutiae of biochemistry. Like ASCP’s board exam, it was a mix of hematology, microbiology, immunology, with added clinical vignettes and patient outcomes. At the end of the test day, I didn’t have a single neuron left working at 100%, but I’ve since recovered. And now it’s onto the next chapter: clinicals. Hope to catch you all again soon, as I’ll try to write up some interesting lab-related cases I will most assuredly come across. Thanks!

 

aki-fig-4
Figure 4. One of many medical students’ bibles. (Stock photo from Amazon.com)

References

Rohde, R., Falleur, D. Ellis, J. (2015) “Almost anyone can perform your medical laboratory tests – wait, what?” Elsevier.com March 10th, 2015; retrieved from: https://www.elsevier.com/connect/almost-anyone-can-perform-your-medical-laboratory-tests-wait-what

 

Centers for Medicaid and Medicare Services (2016) Personnel Policies for Individuals Directing or Performing Non-waived Tests, Revised due to typographical error under citation of §493.1443(b)(3). Center for Clinical Standards and Quality/Survey & Certification Group. April 1, 2016; retrieved from: https://www.cms.gov/Medicare/Provider-Enrollment-and-Certification/SurveyCertificationGenInfo/Downloads/Survey-and-Cert-Letter-16-18.pdf

 

ckanakisheadshot_small

Constantine E. Kanakis MSc, MLS (ASCP)CM graduated from Loyola University Chicago with a BS in Molecular Biology and Bioethics and then Rush University with an MS in Medical Laboratory Science. He is currently a medical student at the American University of the Caribbean and actively involved with local public health.