Duke criteria for infective endocarditis: a patient has persistently positive blood cultures with Streptococcus bovis (S. gallolyticus) and a new oscillating intracardiac mass on echocardiography. Which additional investigation is now strongly recommended in this specific organism?
- A HIV serology — S. bovis endocarditis is an AIDS-defining illness
- B Colonoscopy — S. gallolyticus (bovis) bacteraemia is strongly associated with colorectal carcinoma or adenomatous polyps ✓
- C Bone marrow biopsy for haematological malignancy
- D Liver biopsy for hepatic abscess as the source
Correct answer: B. Colonoscopy — S. gallolyticus (bovis) bacteraemia is strongly associated with colorectal carcinoma or adenomatous polyps
Explanation
Streptococcus bovis (now reclassified as S. gallolyticus subsp. gallolyticus) bacteraemia and endocarditis have a well-established association with colorectal carcinoma (and adenomatous polyps) — the gut mucosal disruption from colonic neoplasia facilitates bacteraemia. Colonoscopy is therefore mandatory after treatment of S. gallolyticus endocarditis to exclude underlying colorectal malignancy. Up to 25-50% of patients with S. bovis endocarditis will have a colorectal neoplasm. This is a classic high-yield clinical correlation in NEET PG Medicine.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.