Introduction: Probiotics are live microorganisms that, when consumed in sufficient quantity, are intended to confer a health benefit. According to the NIH, probiotics are the third most used dietary supplement in the United States, with most formulations containing bacteria of the Lactobacillus genus. Despite limited clinical evidence and unclear mechanism of action, probiotics are commonly used to promote or restore the intestinal microbial balance of both healthy and ill patients. Due to significant dysbiosis in patients with inflammatory bowel disease, there has been a growing interest in the prophylactic and therapeutic potential of probiotic use.
Case Description/Methods: Our case describes a 69 year-old male presenting with 1-week of fevers, fatigue, and arthralgias shortly after a 2.5-month course of corticosteroids and intermittent levofloxacin treatments. His medical history included bioprosthetic aortic valve replacement 2-years prior and ulcerative colitis taking daily balsalazide and lactobacillus-containing probiotics. On presentation the patient met 3 of 4 SIRS criteria for shock with suspected infectious etiology. Empiric IV antibiotics and fluid resuscitation was initiated, with vasopressors added for persistent hypotension. Blood cultures revealed Lactobacillus rhamnosus bacteremia at 31 hours and antibiotics were deescalated to IV ampicillin. Four days after hospital discharge the patient experienced acute right-sided paresthesia and paresis. Upon return to the emergency room, magnetic resonance imaging of the brain demonstrated numerous ring-enhancing lesions with hemorrhagic transformation. Transesophageal echocardiogram revealed a new mobile density on the bioprosthetic aortic valve, raising the suspicion for Lactobacilli rhamnosus infective endocarditis with secondary septic emboli to the brain. The patient was subsequently treated with IV gentamycin and ampicillin, with transition to indefinite oral amoxicillin suppressive therapy.
Discussion: Considered non-pathogenic flora, studies have shown Lactobacilli to be the most common bacteria to translocate the intestine. Nevertheless, opportunistic infections in healthy individuals are rare owing to an intact intestinal barrier and rapid immune clearance of translocated bacteria. The present case highlights the increased literature-reported risk of Lactobacillus translocation in patients who are immunocompromised, use microbiome-disrupting antibiotics, or suffer from disorders associated with increased intestinal barrier permeability.
