[Molecular identification of corynebacterium minutissimum in skin lesions suspicious for erythrasma by the PCR method]

Erythrasma is a chronic superficial infection of the intertriginous areas. Most laboratories use methylene blue stain and 10% KOH smear to identify Corynebacterium minutissimum [C. minutissimum] by direct observation of filamentous bacilli. Occasionally atypical forms can be seen that create problems in diagnosis. This study aims to use the polymerase chain reaction [PCR] method in order to definitively identify C. minutissimum as an agent of erythrasma. This research was performed during 2013 on 100 skin scrapings suspicious for erythrasma which were obtained from various medical mycology laboratories in Tehran. Samples were tested by three methods - direct examination, culture and PCR. DNA was extracted by the modified phenol-chloroform method after which PCR was performed using designed primers. We sequenced some of the PCR products. The sensitivity and specificity of the PCR method was compared to the direct and culture examinations. Of the 100 samples, there were 25 positive samples according to PCR analysis, 13 positive by direct examination and 23 that cultured positive. DNA sequencing results showed the presence of C. minutissimum. The PCR method in comparison with direct examination had a sensitivity of 100% and a specificity of 86.2%. The study also showed that the PCR method in comparison with culture had a sensitivity of 100% and a specificity of 97.4%. This study showed that the PCR method in comparison with the direct method and culture had a higher sensitivity in the detection of C. minutissimum. The present PCR method confirmed all typical and some of the atypical forms of C. minutissimum which indicated the importance of this method in the definitive diagnosis of erythrasma

In vitro susceptibility of aflatoxigenic and non-aflatoxigenic aspergillus flavus strains to conventional antifungal agents

Presently appearance of resistance to antifungal agents among Aspergillus species is dramatically increasing. The objective of this study was to look at the in vitro activities of antifungal drugs against Iranian clinical [from nail, bronchoalveolar lavage, paranasal sinus] isolated A. flavus strains. The susceptibility of 45 aflatoxigenic and non-aflatoxigenic Aspergillus flavus strains were evaluated to six antifungal agents [caspofungin, itraconazole, amphotericin B, ketoconazole, fluconazole, nystatin] using CLSI M38-A2 broth microdilution method. The results indicated that 57.1%, 28.6% of aflatoxigenic and 25.8%, 6.5% of nonaflatoxigenic isolates were susceptible to caspofungin, amphotericin B respectively. All isolates but one aflatoxigenic strain were sensitive to ketoconazole. All 45 strains showed to be resistant to nystatin. Also 64.28%, 92.9% of aflatoxigenic and 64.51%, 100% of non-aflatoxigenic isolates were resistant to fluconazole and itraconazole in ranking order. There was no statistically significant difference between the susceptibilities of aflatoxigenic and non-aflatoxigenic strains of A. flavus to tested antifungal agents

Isolation of Candida species from the bronchoalveolar tavage in patients with pulmonary diseases

Definite diagnosis of Candida pneumonia remains a problem in medicine. Although, isolation of'Candida spp. from the bronchoalveolar lavage is not diagnostic by itself, it may be helpful in early diagnosis of pulmonary candidiasis in immunocompromised or critically ill patients and prompt antifungal therapy. In a cross- sectional study, bronchoalveolar lavage was obtained from 144 patients with pulmonary diseases and different predisposing factors. All specimens were examined by direct microscopy and inoculated on CHOROM agar Candida plates. Corn-meal agar medium and API 20C diagnostic kit also were used for identification of different stains of'Candida. Candida spp. was isolated from 74 [51.3%] specimens. The most common isolated species was Candida albicans with frequency of 69.7%, followed by C.glabrata [20.2%], C.kefyr [5.6%], C.krusei [2.25] and C.tropicalis [1.2%]. Hypercolonization [>/= 10[3] CFU/mL] was found in 10 patients. This report implies the high frequency [30.3%] of non- albicans Candida spp. isolated from respiratory tract, necessity the application of other diagnostic methods and following up the patients. Less susceptibility ofnon- albicans Candida spp. to present anti- fungal drugs must be noted and hypercolonization of respiratory tract with Candida spp. should be considered as a initiating factor for invasive candidiasis