S1797 Curved Rod Threw a Curveball: Rare Case of Campylobacter upsaliensis Bacteremia, Chronic Diarrhea, and a Negative Stool PCR

Abstract

Introduction: The genus Campylobacter includes 32 species, with C. jejuni and C. coli most commonly responsible for enteritis and extragastrointestinal manifestations such as bacteremia.[1,2] However, other species such as C. upsaliensis are increasingly found to be associated with disease.[3] We present a unique case of Campylobacter upsaliensis bacteremia in a patient with chronic diarrhea, a negative common, commercially available stool PCR test for Campylobacter, and otherwise negative workup. Case Description/Methods: A 64-year-old male with NASH cirrhosis, diabetes mellitus, and severe aortic stenosis s/p TAVR presented with non-bloody, watery bowel movements (up to 10/day) for more than 6 weeks. He denied fevers, chills, emesis, abdominal pain, recent antibiotic use, or travel. He lived alone with two dogs and a cat. Initial work-up was negative including fecal calprotectin, stool O&P, stool PCR (BD MAX Enteric Bacterial Panel), [4] and C. difficile. He underwent colonoscopy and biopsies were negative for microscopic colitis, showing only minimal architecture distortion which could be consistent with chronic infection. Subsequently, The MALDI-TOF identified Campylobacter upsaliensis from blood cultures. IV azithromycin was initiated, and repeat cultures remained negative. His symptoms improved and he was discharged home with a 14-day course of therapy. Discussion: Stool PCR has replaced stool culture in many acute clinical settings due to rapidity of results and wider availability. Although the stool PCR used was noted to target Campylobacter spp., only Campylobacter spp. jejuni and coli are included, impeding our ability to detect C. upsaliensis with this common testing method. In an otherwise negative work up it may be prudent to consider stool testing for other less common but emerging subspecies in patients with diarrhea.Figure 1.: Top: transverse colon; grossly normal. Bottom: ascending colon with erythematous friable mucosa.