Introduction: One of the bacterial agents that has been found to be associated with colorectal cancer is Streptococcus bovis, with 13% of infective endocarditis cases caused by this pathogenic species.
Case presentation: We describe the case of a 57-year-old Caucasian man with infiltrating and ulcerating metastatic adenocarcinoma of the sigmoid colon. The patient was receiving second-line chemotherapy treatment and, on the eighth day of the second cycle, he developed a grade IV pancytopenia. We diagnosed a severe sepsis with positive blood cultures for Streptococcus bovis/gallolyticus with a secondary endocarditis.
Conclusions: A recent study suggests that the majority of patients affected by colonic cancer have a Streptococcus bovis/gallolyticus colonization that becomes apparent as an overt infection only when immunosystem disorders or cardiac valve lesions occur. This correlation is important for involving more specialists in a correct and early diagnosis of this rare, but potentially fatal, complication.