Bifidobacterium Bacteremia in a 15 YO Male with Ulcerative Colitis

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Journal of Investigative Medicine





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Introduction We report a 15 year old male with history of ulcerative colitis flare ups presenting with a rare Bifidobacterium blood culture isolate. Bifidobacterium is commonly found in probiotics and rarely causes human infections, but it has a potential for bacteremia in an immunocompromised host. Case description A 15 year old male with ulcerative colitis and type 1 diabetes presented with 6–8 weeks of bloody diarrhoea. After a 6 month remission of ulcerative colitis, a prednisone wean was attempted twice, but he developed flare ups with episodes of bloody diarrhoea and concurrent URI symptoms. He reported weight loss, decreased appetite, and had elevated ESR/CRP. He was given methylprednisone, mercaptopurine, and infliximab. Colonoscopy and EGD showed intraoperative evidence of pancolitis and duodenitis with active chronic colitis on surgical pathology. Post-procedurally, he developed persistent fevers. Given the immunosuppression, he was given cefepime, azithromycin, vancomycin and metronidazole. An extensive workup was done including blood, fungal, and streptococcal cultures which returned no growth. CT abdomen showed incidental finding of asymptomatic left lower pneumonia. Sputum cytology/culture were unremarkable. CMV, Influenza, respiratory viral panel, Cryptococcus, Aspergillus, Fungitell, legionella, mycoplasma, EBV returned negative. Stool culture were negative. However, a repeat blood culture isolated Bifidobacterium species. Patient improved clinically with broad antibiotics coverage. Discussion Bifidobacterium spp is commonly found in probiotics. These anaerobic, gram-positive rods are part of the normal oral, vaginal, and intestinal flora. Probiotics have been used in inflammatory bowel disease because it protects GI by altering gut microbiota and modulating immune responses. However, Bifidobacterium can act as an opportunistic bacteria and cause bacteremia in rare cases in immunocompromised patients. A study in Norway analysed antibiotic susceptibility of these rare bifidobacterial blood culture isolates and demonstrated low MICs (≤0.5 mg/litre) to beta-lactam antibiotics, vancomycin, and clindamycin and relatively high MICs to ciprofloxacin and metronidazole. This case illustrates the invasive potential of Bifidobacterium bacteremia in immunocompromised host.


Medicine and Health Sciences



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