Pseudofungi Associated with a Granulomatous Response in a Lymph Node: A Case Report

ABSTRACT

. We present herein a case of pseudofungi incidentally found in the mediastinal lymph nodes of a 31-year-old woman who had a left pneumonectomy for a pulmonary blastoma. The pseudofungi were located in the subcapsular sinuses of the lymph nodes with an associated granulomatous reaction. They revealed yellowish-brown hyphae-like structures with pseudosepta and irregular branching at various angles intermingled with round yeast-like forms. These structures stained positively with periodic acid-Schiff and Gomori methenamine silver, but also stained strongly positive for Prussian blue suggesting that they contain iron. The characteristic morphological features of pseudofungi are discussed with emphasis on the features that distinguish them from true fungal organisms.