Cytopathologic diagnosis of extracolonic amebiasis

Extracolonic amebiasis must be distinguished from bacterial abscesses and neoplastic disease. Newer technology in diagnostic and interventional radiology permits such lesions to be aspirated more accurately for both diagnostic and therapeutic purposes, often averting an open surgical procedure. Paracecal and hepatic masses of one patient, who presented with fever and abdominal pain, were shown to be amebic abscesses by cytopathologic examination of material obtained by ultrasonically guided percutaneous fine needle aspiration. Another patient, who was thought to have metastatic carcinoma, died, with clinically unrecognized extensive pulmonary and hepatic amebiasis proven at autopsy. A review of this patient's sputum cytology smears showed numerous trophozoites of Entamoeba histolytica that were not recognized earlier. Cytopathologic studies of sputum and fine needle aspirates is an important means of detecting extracolonic amebiasis and distinguishing these lesions from neoplastic disease.