Microbiology Case Study: Worsening Liver Function and Bacteremia in a 35 Year Old Male

Case History

A 35 year old male with a history of alcohol use disorder in early remission, acute alcoholic hepatitis with multiple admissions for worsening liver function was admitted for acute kidney injury and worsening encephalopathy. Blood cultures were collected due to leukocytosis and the anaerobic bottle flagged positive for gram negative bacilli at 4.6 days. The organism, shown in Image 1, was sent to a reference laboratory and was identified as a Campylobacter species, unable to further identify. The patient will receive a liver transplant at another institution.

Discussion

Campylobacter species are gram-negative, oxidase-positive, non-fermenting, microaerophilic, non-spore forming, motile rods typically with one or more helical turn.^1,2 When two bacteria form short chains, these appear as “S” shaped and/or “gull-wing” shaped. These bacteria are generally 0.2 µm by 0.5-5.0 µm in size and can be as long as 8.0 µm.¹ Campylobacter species are widely distributed in most warm-blooded animals (e.g., poultry, cattle, pigs, sheep, cats, and dogs) and they grow optimally at 37-42 °C. There are more than 20 Campylobacter species, not all of which cause illness but are potentially pathogenic. Campylobacter jejuni accounts for approximately 90% of human Campylobacter infections, while less common species such as Campylobacter coli, Campylobacter upsaliensis, Campylobacter fetus, and Campylobacter lari can also cause infection.³

Transmission of Campylobacter is believed to be foodborne via undercooked meat (particularly poultry), unpasteurized milk, or improperly treated water. Person-to-person transmission is rare, but may occur via the fecal-oral route. The infection load for Campylobacter species is relatively low, with fewer than 500 organisms causing infection.⁴ In human infection, these bacteria usually colonize the intestinal tract leading to diarrhea (often bloody), stomach cramps, fever, nausea, and vomiting.⁵ Clinical manifestation usually occurs 2 to 5 days after the individual is infected and lasts approximately a week. Diagnosis is established definitively by stool culture and sometimes by blood culture.² In some cases, long-term effects of Campylobacter infection include an array of clinical syndromes including enteritis, bacteremia, arthritis, septic abortion, meningitis, irritable bowel disease, and Guillain-Barre syndrome [4]. Individuals with a greater risk for infection include those 65-years or older, pregnant women, and those with weakened immune systems.⁵

Campylobacteriosis is the most common form of acute infectious diarrhea in developed countries with a higher incidence than both Salmonella and Shigella.¹ The Center for Disease Control and Prevention estimates that 1.5 million people in the United States are affected by Campylobacter infection each year—making it the most common bacterial cause of diarrheal illness in the United States.³ Unfortunately, the incidence of hepatitis associated with Campylobacter species infection is unknown, as few case-reports related to Campylobacter colitis⁶and Campylobacter jejuni ^7,8,9,10 have been published. Although the liver is often involved in systemic infections resulting in various types of abnormal liver function tests, mild to severe hepatocellular dysfunction is an uncommon observation in those with Campylobacter infection.

Most individuals infected with any Campylobacter species recover with only fluid replenishment while the diarrhea lasts and no antibiotic treatment. However, those with or at risk for severe illness should be considered for antibiotic treatment. The antibiotics that are used to treat infection are azithromycin and fluoroquinolones (usually resistant). Antimicrobial susceptibility testing can help guide appropriate therapy.³

References

1. Hardy Diagnostics. Campylobacter [Internet]. 2016. Available from: https://catalog.hardydiagnostics.com/cp_prod/Content/hugo/Campylobacter.htm#:~:text=In%20general%2C%20Campylobacter%20spp.%20appear%20as%20gray%2C%20flat%2C,glistening%2C%20with%20little%20spreading.%20Campylobacter%20spp.%20are%20non-hemolytic.
2. Perez-Perez GI, Blaser MJ. Campylobacter and Helicobacter. In: Baron S, editor. Medical Microbiology. Galveston (TX): University of Texas Medical Branch at Galveston Copyright © 1996, The University of Texas Medical Branch at Galveston.; 1996.
3. Centers for Disease Control and Prevention. Campylobacter (Campylobacteriosis) For Health Professionals [Internet]. 2019 [updated December 23, 2019]. Available from: https://www.cdc.gov/campylobacter/technical.html.
4. Ehrenpreis ED. Campylobacter infection [Internet]. Epocrates2022 [updated January 22, 2022]. Available from: https://online.epocrates.com/v2/print/disease/1175?subSectionId=11#:~:text=Bacteria%20of%20the%20genus%20Campylobacter%20cause%20a%20variety,%5B%203%5D%20There%20are%20many%20species%20of%20Campylobacter.
5. Centers for Disease Control and Prevention. Campylobacter (Campylobacteriosis) Symptoms [Internet]. 2019. Available from: https://www.cdc.gov/campylobacter/symptoms.html.
6. Reddy KR, Farnum JB, Thomas E. Acute hepatitis associated with campylobacter colitis. J Clin Gastroenterol. 1983;5(3):259-62. Epub 1983/06/01. doi: 10.1097/00004836-198306000-00013. PubMed PMID: 6863882.
7. Humphrey KS. Campylobacter infection and hepatocellular injury. Lancet. 1993;341(8836):49. Epub 1993/01/02. doi: 10.1016/0140-6736(93)92521-t. PubMed PMID: 8093289.
8. Vermeij CG, van Dissel JT, Veenendaal RA, Lamers CB, van Hoek B. Campylobacter jejuni peritonitis in a patient with liver cirrhosis. Eur J Gastroenterol Hepatol. 1996;8(12):1219-21. Epub 1996/12/01. doi: 10.1097/00042737-199612000-00016. PubMed PMID: 8980944.
9. Korman TM, Varley CC, Spelman DW. Acute hepatitis associated with Campylobacter jejuni bacteraemia. Eur J Clin Microbiol Infect Dis. 1997;16(9):678-81. Epub 1997/11/14. doi: 10.1007/bf01708559. PubMed PMID: 9352262.
10. Yoon JG, Lee SN, Hyun HJ, Choi MJ, Jeon JH, Jung E, et al. Campylobacter jejuni Bacteremia in a Liver Cirrhosis Patient and Review of Literature: A Case Study. Infect Chemother. 2017;49(3):230-5. Epub 2017/06/14. doi: 10.3947/ic.2017.49.3.230. PubMed PMID: 28608661; PubMed Central PMCID: PMCPMC5620392

-Amelia M. Lamberty is a MS in Pathology student at the Larner College of Medicine at the University of Vermont.

-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.