A M Marty1, A J Chester. 1. Pathology Department, Armed Forces Institute of Pathology, Washington, DC 20306-6000, USA.
Abstract
BACKGROUND: Contributors regularly submit specimens to our institute and suggest a diagnosis of cestode infection, but the structures in question are actually lipomembranous changes that produce lipid pseudomembranes. This required a reproducible method to distinguish lipid pseudomembranes from body walls of cestodes. METHODS: We describe and compare the morphologic and histochemical features of specimens from 20 patients. Nine specimens represented lipid pseudomembranes, and 11 represented one of the following five entities: cysticercus, coenurus, sparganum, hydatid of Echinococcus granulosus, or metastatic solid-bodied cyclophyllidean (possibly cysticercoid) larval cestodes. Specimens were stained with hematoxylin-eosin, Gomori's methenamine-silver, and 72-hour oil red O. Nine patients with cestodes, and all with lipid pseudomembranes, presented with subcutaneous lesions. RESULTS: In all specimens, oil red O provided marked contrast between lipid pseudomembranes and surrounding tissue, but focal or minimal contrast between larval cestodes and surrounding tissue. Unlike hematoxylin-eosin, Gomori's methenamine-silver stain produced distinctly different staining patterns in larval cestodes and lipid pseudomembranes. CONCLUSIONS: This technique readily permitted a simple, reproducible, and accurate distinction between lipid pseudomembranes and cestode body walls and distinguished between body walls of different cestodes.
BACKGROUND: Contributors regularly submit specimens to our institute and suggest a diagnosis of cestode infection, but the structures in question are actually lipomembranous changes that produce lipid pseudomembranes. This required a reproducible method to distinguish lipid pseudomembranes from body walls of cestodes. METHODS: We describe and compare the morphologic and histochemical features of specimens from 20 patients. Nine specimens represented lipid pseudomembranes, and 11 represented one of the following five entities: cysticercus, coenurus, sparganum, hydatid of Echinococcus granulosus, or metastatic solid-bodied cyclophyllidean (possibly cysticercoid) larval cestodes. Specimens were stained with hematoxylin-eosin, Gomori'smethenamine-silver, and 72-hour oil red O. Nine patients with cestodes, and all with lipid pseudomembranes, presented with subcutaneous lesions. RESULTS: In all specimens, oil red O provided marked contrast between lipid pseudomembranes and surrounding tissue, but focal or minimal contrast between larval cestodes and surrounding tissue. Unlike hematoxylin-eosin, Gomori'smethenamine-silver stain produced distinctly different staining patterns in larval cestodes and lipid pseudomembranes. CONCLUSIONS: This technique readily permitted a simple, reproducible, and accurate distinction between lipid pseudomembranes and cestode body walls and distinguished between body walls of different cestodes.