Vesicular thick-walled swollen hyphae in pulmonary zygomycosis.
An autopsy case of pulmonary zygomycosis in a patient with rheumatoid arthritis on immunosuppressive therapy is presented herein. There was a pulmonary cavitated infarct caused by mycotic thrombosis. Thin-walled narrow hyphae and vesicular thick-walled swollen hyphae were found on the pleural surface and in the necrotic tissue at the periphery of the cavity. Findings of such shaped fungal elements may cause erroneous histopathological diagnosis because pauciseptate broad thin-walled hyphae are usually the only detectable fungal elements in zygomycosis tissue. Although immunohistochemistry confirmed these unusual elements to be zygomycetous in the present case, it is important for the differential diagnosis to be aware that zygomycetes can form thin narrow hyphae and vesicular thick-walled swollen hyphae.
Kimura
Masatomo
M
Department of Pathology, Kinki University School of Medicine, Osaka-Sayama, Osaka, Japan. kimura-m@med.kindai.ac.jp
Ito
Hiroyuki
H
D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000188:drug therapy; D001344:Autopsy; D006801:Humans; D025301:Hyphae / Q000648:ultrastructure*; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008171:Lung Diseases / Q000276:immunology / Q000382:microbiology* / Q000473:pathology*; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000188:drug therapy; D008297:Male; D020096:Zygomycosis / Q000150:complications / Q000276:immunology / Q000473:pathology*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D007166:Immunosuppressive Agents