Diagnostic Accuracy of Histopathologic and Cytopathologic Examination of Aspergillus Species

Abstract

To assess the diagnostic accuracy of histopatho-logic and cytopathologic examination (HCE) of Aspergillus species (spp), we performed an 11-year retrospective review to correlate surgical/cytology cases with a diagnosis of Aspergillus spp with their concurrent fungal culture results. Diagnostic accuracy was defined as the percentage of cases with culture-proven Aspergillus spp divided by the number of cases diagnosed as Aspergillus spp on HCE that had growth on fungal culture. Ninety surgical/cytology cases with concurrent fungal culture were reviewed, 58 of which grew a fungal organism. Of these 58 cases, 45 grew an Aspergillus spp, whereas 13 grew an organism other than Aspergillus spp, including both common (Scedosporium, Fusarium, and Paecilomyces spp) and uncommon mimickers (Trichosporon loubieri), resulting in a diagnostic accuracy of 78%. The low diagnostic accuracy indicates that several fungal organisms can morphologically mimic Aspergillus spp and can only be distinguished by fungal culture and DNA sequencing.

Diagnosis of invasive fungal diseases in haematology and oncology: 2018 update of the recommendations of the infectious diseases working party of the German society for hematology and medical oncology (AGIHO)

“…Thrombosed vessels in biopsy or autopsy material should always be examined very carefully by the pathologist, and numerous serial sections should be analysed. The detection of fungal pathogens by histopathology and the differentiation may be improved by immunohistochemical examination or using molecular techniques and these tools should be used to identify any fungal pathogen detected in histopathology samples to the genus and preferrentially species level …”

Aspergillus PCR-Based Investigation of Fresh Tissue and Effusion Samples in Patients with Suspected Invasive Aspergillosis Enhances Diagnostic Capabilities

“…In addition, a number of fungal species are histomorphologically similar to Aspergillus, including Scedosporium, Penicillium, and Fusarium. To make matters even more complicated, it was shown recently that histologically suspected species and culturally identified species differ in the majority of cases (9). Therefore, using a method with higher sensitivity and specificity such as PCR might improve the diagnostic capabilities, especially as often prevalent necrosis can make histological identification of IFD exceptionally difficult for the pathologist.…”

“…Although biopsies confer the possibility of identifying the etiology of infections, the sensitivity of culture-based methods is as low as 30% (8) and histological and culture results are often not congruent (9); thus, molecular methods have become increasingly important. In a recent retrospective reevaluation of formalinfixed, paraffin-embedded (FFPE) samples, the original species identification was corrected using molecular techniques (9).…”

“…In a recent retrospective reevaluation of formalinfixed, paraffin-embedded (FFPE) samples, the original species identification was corrected using molecular techniques (9).…”

Progress in the Diagnosis of Invasive Fungal Disease in Children

“…Blood cultures are further limited by slow turn-around time and will not be positive in deep seated Candida infections including hepatosplenic candidiasis. Aspergillus species are rarely cultured from blood samples [6], and diagnostic accuracy of histopathological examination is below 80% [7]. Although most moulds are hardly recovered from blood cultures, positive blood cultures are more often obtained in IFD caused by Scedosporium spp., Fusarium spp.…”