Molecular Identification of Fungi Causing Tissue Mycoses From Formalin Fixed Paraffin Embedded (FFPE) Archive Specimens

Introduction: Isolation of fungi from tissue specimens using conventional methods is time consuming. However, in some cases, the histopathological examination (HPE) alone unable to provide a definite identity fungus. Alternatively, non-culture method, such as polymerase chain reaction (PCR) detecting internal transcribed spacer (ITS) rRNA genes fungi, promising diagnostic tool for rapid and accurate diagnosis mycoses. Methods: This work investigated utility panfungal PCR identifying agents mycoses 87 FFPE archive specimens. Deoxyribonucleic acid (DNA) extraction was performed on by QIAamp DNA Tissue Kit. The ITS2 region amplified ITS3/ITS4 primers. products were sequenced same primers compared NCBI nucleotide database species identification. Results: Fungal successfully 52 (59.8%) specimens, which only 23 (44.0%) consistent with clinical/HPE findings. identified Aspergillus spp., Candida Penicillium Cryptococcus neoformans, Talaromyces marneffei, Rhizopus oryzae. A few rare also identified, Diaporthe longicolla fungus-like oomycete Pythium insidiosum that are commonly associated plant pathogens. Conclusion: Although able offer genus/species identification, utilising this method paraffinised must be evaluated considering many factors will reduce its sensitivity specificity. Therefore, it important correlate results clinical HPE findings obtain correct adequate treatment