Abdominal actinomycosis: complication of endoscopic stenting in chronic pancreatitis?

Pancreatic endotherapy is frequently performed in patients with chronic pancreatitis and stenoses of the main pancreatic duct. In a patient with long-standing chronic pancreatitis and treatment with pancreatic stents, metastatic pancreatic head carcinoma was suspected because of infiltration of the neighboring organs and hepatic lesions. Ultrasound-guided aspiration of one liver lesion revealed grains typical for actinomycosis. In the light of this case, an extracted pancreatic stent was microbiologically investigated for actinomycetes in another patient who had a suspicious lesion of the pancreatic head. Microbiological examination of the extracted pancreatic stent revealed colonization by Actinomyces meyeri, Klebsiella oxytoca, and mixed cultures of anaerobic and saprophytic Gram-positive bacteria. In the following weeks, she developed a septic clinical picture with multiple abscesses of the liver. Actinomyces meyeri, Corynebacterium species, Candida and Enterococcae were cultivated in the aspirates. It seems possible, that treatment with pancreatic stents could have caused invasion of actinomycetes into the parenchyma of the pancreas, which was already harmed by the chronic inflammation, followed by the typical infiltrative growth and hematologic or biliary seeding into the liver.