Disseminated Fungal Infections at Autopsy: A Review of 59 Patients in a Single University Medical Center with Detection of Multiple Fungal Species Confirmation by In Situ Hybridization.
Christine Louie, Leslie A Litzky, Adrienne Carruth-Griffin, Irving Nachamkin, Kathleen T Montone. University of Pennsylvania, Philadelphia
Background: Disseminated fungal infections are an important cause of death in immunosuppressed patients; however fungal infections are not always suspected and culture confirmation is not always possible. We performed an analysis of 59 autopsies with disseminated fungal infection including clinical history, histologic findings, and the involved fungal pathogens identified by histology, culture and/or in situ hybridization (ISH) using species/genus specific probes.
Design: Files were searched for autopsies with disseminated fungal infections from 1996-2010. Clinical information, reports, slides and fungal pathogens were reviewed. In addition, ISH using species/genus specific biotin-labeled oligonucleotide probes targeting Aspergillus sp., Zygomyces, Candida albicans, Fusarium sp., and C. immitis were performed in cases with and without positive cultures.
Results: 59 patients with multi-site fungal infections were identified. Disseminated fungal infections were suspected in only 31 patients (53%). Underlying immunosuppression was observed in 58 patients (20 transplant, 13 malignancy, 11 steroids, 3 AIDS, 5 liver disease, 6 other). 17 (29%) had multiple reasons for immunosuppression. Sites involved included lung (52), GI/liver/pancreas (27), heart (26), GU tract (25), spleen (14), thyroid (12), and CNS (11). 41 patients had histologic evidence of a single fungus while 19 patients had multiple fungi (17: 2 fungi, 2: 3 fungi). 46 patients (78%) had positive fungal cultures of which 29 (49%) grew a single pathogen (14 Aspergillus sp., 9 Candida sp, 2 C. neoformans, 1 C. immitis, 2 Rhizopus sp, 1 Cunninghamella sp); 17 (29%) grew multiple fungi (commonly Aspergillus sp. or Candida sp. and another fungus). 13 patients (22%) had negative cultures. ISH confirmed Aspergillus in 16/22 culture positive cases, Zygomyces in 4/4 culture positive cases, C. immitis in 1 culture positive case, C. albicans in 5/6 culture positive cases, and Fusarium sp. in 1 culture positive case. In addition, ISH identified fungi in 7/13 culture negative cases (3 Aspergillus sp; 3 Zygomyces, 1 Candida sp.)
Conclusions: Disseminated fungal infections are often clinically unsuspected and multiple fungal organisms may be identified in a large percentage of cases. The lung is the most frequent tissue site involved followed by the heart, GI tract, and GU tract. Aspergillus sp. and Candida sp. are the most common isolates in our experience. ISH can aid in fungus identification in cases with negative cultures.
Monday, February 28, 2011 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 193, Monday Morning