Pulmonary Pseudallescheriasis: A case report and Histopathologic Comparision with Pulmonary Aspergillosis

ABSTRACT

Infection by pseudallescheria boydii is an occasional cause of mycetoma, corneal ulcers, endophthalitis, sinusitis, pneumonia, endocarditis, meningitis, arthritis, and osteomyelitis. But, it also causes serious disseminated or localized infection in immunocompromised patients. We report a case of pulmonary pseudallescheriasis developed in a 32-year-old man who has been a sofa manufacturer for several years. He presented with a cystic mass in the lung, 5cm in the largest dimension. Dark green necrotic material was evacuated from the cavity. Microscopically, the cystic wall and adjacent lung parenchyme were infiltrated by histiocytes rather than eosinophils and there was little fibrosis in the wall. The P. boydii was isolated from the cystic contents, which revealed white floccose colonies in Sabouraud dextrose agar and revealed single or multiple-celled oval conidia being produced on short hyalinated hyphae and on the elongated annellides in the slide culture. The differential findings with aspergillosis are discussed.