Splenic Actinomycosis in a Patient with Chronic Granulomatous Disease: A Case Report and Review of the Literature

Actinomycosis is a granulomatous disease caused by filamentous, gram-positive, anaerobic bacteria. Actinomyces spp. are constituents of the normal flora of mucous membranes. These organisms may cause infection after surgery or damage to the mucosal barrier. Main clinical presentations of actinomycosis are cervicofacial, thoracic, and abdominal forms of the disease. Most cases are caused by Actinomyces israelii, whereas cases due to other Actinomyces spp. are occasionally reported. Actinomycosis is often misdiagnosed because it can mimic other pathological conditions. Besides, Actinomyces spp. are difficult to isolate because they require specific growth conditions. Herein we report a case of splenic actinomycosis caused by Actinomyces naeslundii in a 30-year-old woman with chronic granulomatous disease. Abdominal ultrasound imaging revealed hepatic nodules and splenic abscess; the latter was sampled and cultured. After microbiological diagnosis, she received intravenous (IV) penicillin followed by long-term oral amoxicillin-clavulanate. Abscesses regressed with drainage and prolonged antibiotic therapy. The patient was followed-up for six months without any symptoms. Splenic actinomycosis is a rare disease but should be considered in the differential diagnosis of splenic abscesses in patients with chronic granulomatous disease.