Splenic abscess caused by Cutibacterium acnes in a patient with multiple tooth extractions

A woman in her 40s with a history of dental abscess presenting with a 3-month history of nightly fevers, malaise, fatigue and acutely worsening left flank pain was found to have a splenic abscess replacing almost the entire splenic parenchyma on abdominal CT. Abscess aspirate showed Gram-positive rods, and both aerobic and anaerobic cultures grew Cutibacterium acnes (previously Propionibacterium acnes), a common member of the skin microbiome. Prior case reports of C. acnes splenic abscess all involved parental inoculation via needle use. However, in the context of no percutaneous needle exposure and multiple tooth extractions immediately preceding her symptoms, the most likely source of her infection is oral flora with haematogenous or lymphatic spread to the spleen.