“COPPER PENNY” OF PATHOLOGY- CHROMOBLASTOMYCOSIS- A CASE REPORT AND BRIEF REVIEW OF LITERATURE.

Chromoblastomycosis (CBM) is a chronic, granulomatous, mycosis of the skin and subcutaneous tissue produced by the traumatic implantation of various dematiaceous fungi. The most prevalent species (90%) is Fonsecaea pedrosoi. We report a case of a 29 year male presented with complaints of non- healing ulcer since 6-7 months and underwent exploration and curettage. It was diagnosed as chromoblastomycosis in histopathological examination on identication of characteristic copper pennies/sclerotic bodies. Later on patient responded well to oral antifungal and antibiotic therapy. To conclude, CBM although infrequent, must be considered in the differential diagnosis of chronic skin lesions.

FONSECAEA PEDROSOI – A CAUSE OF OCCULAR CHROMOBLASTOMYCOSIS

Fonsecaea pedrosoi (F. pedrosoi) is dematiaceous fungus and is the most common cause for chromoblastomycosis. It affects the exposed skin, mostly of the lower extremities. Arare case of mycotic keratitis was diagnosed in our hospital caused by F. pedrosoi. Corneal sample received in the laboratory was processed by standard mycological methods, F. pedrosoi was isolated, patient was started on antifungals his condition improved and there was no relapse. This case report shows that F. pedrosoi can infect cornea. Further, a prompt diagnosis and vigorous treatment improves patient's clinical condition.

Prediction of itraconazole minimum inhibitory concentration for Fonsecaea pedrosoi using Fourier Transform Infrared Spectroscopy (FTIR) and chemometrics

Fonsecaea pedrosoi is one of the main agents of chromoblastomycosis, a chronic subcutaneous mycosis. Itraconazole (ITC) is the most used antifungal in its treatment, however, in vitro antifungal susceptibility tests are important to define the best therapy. These tests are standardized by the Clinical and Laboratory Standards Institute (CLSI), but these protocols have limitations such as the high complexity, cost and time to conduct. An alternative to in vitro susceptibility test, which overcomes these limitations, is FTIR. This study determined the minimum inhibitory concentration (MIC) of itraconazole for F. pedrosoi, using FTIR and chemometrics. The susceptibility to ITC of 36 strains of F. pedrosoi was determined according to CLSI and with the addition of tricyclazole (TCZ), to inhibit 1,8-dihydroxynaphthalene (DHN)-melanin biosynthesis. Strains were grown in Sabouraud agar and prepared for Attenuated Total Reflection (ATR)/FTIR. Partial least squares (PLS) regression was performed using leave-one-out cross-validation (by steps of quintuplicates), then tested on an external validation set. A coefficient of determination (R²) higher than 0.99 was obtained for both the MIC-ITC and MIC-ITC+TCZ ATR/PLS models, confirming a high correlation of the reference values with the ones predicted using the FTIR spectra. This is the first study to propose the use of FTIR and chemometric analyses according to the M38-A2 CLSI protocol to predict ITC MICs of F. pedrosoi. Considering the limitations of the conventional methods to test in vitro susceptibility, this is a promising methodology to be used for other microorganisms and drugs.