Disseminated coccidioidomycosis presenting as eosinophilic ascites

A man in his 50s with a self-reported history of liver cirrhosis was admitted to the hospital for the treatment of suspected spontaneous bacterial peritonitis (SBP). Initial imaging revealed a mildly nodular liver, a large volume of ascites and omental thickening. He was treated empirically for SBP. Ascitic fluid analysis from paracentesis demonstrated eosinophils and a low serum-ascites albumin gradient. He was discharged from the hospital with a diagnosis of peritoneal carcinomatosis pending work-up for an unknown primary malignancy. An extensive malignancy work-up was negative, but an omental biopsy revealed coccidioidomycosis by culture and histopathology. With high-dose fluconazole therapy, his abdominal pain improved, and his ascites completely resolved. Eosinophilia in ascitic fluid is uncommon and should prompt consideration of rare diagnoses, such as peritoneal coccidioidomycosis, tuberculosis, helminthic infections or eosinophilic gastrointestinal diseases.