S2199 A Rare Case of Intestinal Spirochetosis in an Asymptomatic Immunocompetent Patient

Abstract

Introduction: Human Intestinal spirochetosis is defined as presence of spirochetes attached to the surface of the intestinal mucosa. Intestinal spirochetes comprise of a heterogeneous group of bacteria. In humans, Brachyspira aalborgi and Brachyspira pilosicoli predominate. Intestinal spirochetosis is primarily reported in developing countries and rare in places with high living standards. Immunocompromised patients and homosexuals are at higher risk for colonization and invasive human intestinal spirochetosis. Patients can be asymptomatic or present with diarrhea, abdominal pain, hematochezia and lower GI bleeding. We present a rare case of asymptomatic human intestinal spirochetosis with no risk factors. Case Description/Methods: A 66-year-old White heterosexual male with past medical history of nicotine use disorder, alcohol dependence, and hypertension was referred to the gastroenterology clinic for persistently elevated liver enzymes and abnormal abdominal imaging results. He denied having any gastrointestinal or systemic symptoms except occasional diarrhea and was sexually active with only one female partner for last 40 years. CT scan of the abdomen & pelvis showed hepatic steatosis, sigmoid diverticulosis with sigmoid wall thickening and a fistulous communication between the sigmoid colon and bladder dome. An active open fistula between bowel and bladder was considered. Further evaluation with colonoscopy showed a total of 2 large polyps and multiple sigmoid diverticula but no evidence of fistula. Histopathology of biopsies showed hyperplastic, adenomatous polyps and spirochetes. Warthin-Starry stain was positive for Barchyspira spirochetes from all the tissue specimens. Patient was referred to an infectious disease specialist. HIV and Rapid Plasma Regain (RPR) were negative. The decision was made to monitor the clinical condition and avoid antibiotics for time being, given the absence of symptoms and concurrent alcohol use. A surgical evaluation was planned to look into a possible colo-vesical fistula, but patient was lost to follow-up (Figure). Discussion: Intestinal spirochetosis is known to cause havoc in veterinary medicine, especially in the swine population (Our patient lived in a trailer park and worked with goats, chickens, dogs, and cats). Intestinal spirochetosis in humans and its clinical significance in an asymptomatic immunocompetent patient is poorly understood. Antibiotics are not recommended unless the patient is symptomatic. If recommended metronidazole is the choice of treatment.Figure 1.: Intestinal Spirochetosis.