Yellow-brown (Hamazaki-Wesenberg) bodies mimicking fungal yeasts.

We describe herein two cases in which yellow-brown (Y-B) bodies, also known as Hamazaki-Wesenberg bodies, were encountered in lymph nodes and initially misinterpreted as fungal organisms. Because of occasional "budding" forms and positive staining with "screening" fungal stains (Grocott methenamine silver and periodic acid-Schiff), Y-B bodies may closely resemble budding yeast fungi. We describe the characteristic light microscopic and ultrastructural morphologic features of Y-B bodies, and their histochemical staining reactions, and emphasize the value of the Fontana-Masson silver stain for recognition and identification of these bodies.