Hepatobiliary and pancreatic: Hepatic actinomycosis

Abstract

A 72-year-old man was investigated because of a 1-week history of fever, headache and myalgia. Seven years previously, he had been diagnosed with gastric adenocarcinoma and treated with a subtotal gastrectomy. On admission to hospital, his temperature was elevated (38.3°C) but no other abnormalities were detected on physical examination. Laboratory tests revealed mild anemia (hemoglobin 114 g/l), an elevated white cell count (12.6x109/l) and a mild elevation of C-reactive protein (13.6 mg/l), aspartate aminotransferase (53 u/l), alanine aminotransferase (65 u/l), alkaline phosphatase (222 u/l) and γ-glutamyl transferase (264 u/l). His serum glucose was also elevated. A contrast-enhanced computed tomography (CT) scan showed several lesions of low-attenuation in both lobes of the liver (Figure 1). The differential diagnosis included liver abscesses and liver metastases. A percutaneous aspirate was obtained under ultrasound guidance and yielded thick brown turbid fluid. In wet-fixed smears, blue colonies of actinomycosis with “bales of wool” appearance were seen on a background of mixed inflammatory cells (Figure 2). In cell-block sections, there were many irregularly lobulated or scalloped basophilic granules termed “sulphur granules” that are characteristic of Actinomyces. There was no evidence of metastatic adenocarcinoma. Gram staining revealed positive filamentous bacilli (Figure 2 inset, white arrow). The patient was treated with percutaneous drainage for 2 weeks and with high-dose penicillin-G given intravenously. His fever subsided after 2 weeks and laboratory tests gradually returned to normal. The abscesses had resolved on repeat CT scan after 2 months.