iotrophia defectiva: A Rare Gut Pathogen Resulting Endocarditis in Inflammatory Bowel Disease

Abstract

Clinical History: A 44-year-old man has ulcerative colitis (UC) for the last 3 years on maintenance twice daily oral mesalazine 2 g. Five months ago, investigation showed that his UC was in deep remission (clinical, endoscopic, and histological). A month prior to admission, his C-reactive protein (CRP) start to rise (39.8 MH/L from baseline of 1.8 MG/L). Computer tomography of abdomen and pelvis excluded intraabdominal collections, abscesses, or colitis. Incidental finding include a subcentimeter hypoattenuation area at left kidney. One month later, he was admitted for rectal bleeding with non-specific abdominal discomfort. He had no risk factors for endocarditis including prior valvular heart disease, central catheter insertion, or intravenous drug abuse. Investigation: Raise CRP (87.3 MG/L) and leucocytosis (16 × 109/L) was noted. Blood and stool cultures as well as Clostridium difficile PCR were negative. He was treated as mild UC flare. Differential Diagnosis: Mild UC flare and endocarditis. Progression: His stool calprotectin was 73 ug/g on arrival. At the same time, a new ejection systolic murmur was detected on admission. Transesophageal echocardiography showed multiple mitral valve vegetations. Repeated blood cultures grew Abiotrophia defectiva after 53 hours of incubation. Dental review excluded oral pathology. Following diagnosis of A. defectiva endocarditis, he completed 4 weeks of intravenous benzylpenicillin and gentamicin. No further embolic or cardiac complications after 3 months of follow up. Learning Point of This Case: A. defectiva, a gut pathogen, can cause subacute endocarditis in UC. Adequate blood sample and incubation period is required to detect this fastidious organism. It is associated with high morbidity and relapse despite appropriate treatment. Conclusion: A. defectiva, a rare gut pathogen, can result in subacute endocarditis, mimicking UC flare. More data on incidence of endocarditis among UC is required to guide the role of prophylactic antibiotic among UC patients undergoing endoscopy.