Differentiation of Oral Candida Species in Chronic Renal Failure Patients Undergoing Hemodialysis

Background: Oral candidiasis occur as an opportunistic infection. The transition of candida from commensal to pathogen is often associated with immune- compromised chronic renal patients receiving hemodialysis. Candida species identification and differentiation is important for treatment in these patients. Aim: To differentiate candida species present in the oral cavity of chronic renal failure patients undergoing hemodialysis. Material and Methods: A total of 120 individuals with study group (n=60) of chronic renal failure patients undergoing hemo- dialysis (CRF with HD) and control group (n=60) healthy individuals, were studied. Salivary samples were cultured for candida species using Sabouraud’s Dextrose Agar (SDA) and CHROM agar culture media, for the growth of candida species in 24, 48 to 72 hours at 37ºC. Colonies were counted and quantitatively expressed as colony forming units/milliliter (CFU). Results: Positive candidal growth was seen on SDA and CHROM agar medium among CRF with HD and Control Groups, can- dida species were present in 55 (91.6%) and absent in 5(8.3%) and 57(95%) and absent 3(5%) in individuals respectively. Can- dida species differentiation in CRF with HD and Control groups were C. albicans (green colonies), C. Kruzei (pink colonies) and C. Tropicalis (blue colonies) were 46(81.6%), 6(10.0%), 2(3.3%) in CRF with HD cases while 45(75%) 11(18.3%) and 0(0%) in control cases respectively. Conclusion: Isolation and differentiation of candida was highly significant (p<0.05) in chronic renal failure patients undergoing hemodialysis than healthy individuals.

Mycological study of dermatophytosis in a part of South India

Aims: Epidermophyton, Microsporum and Trichophyton are the genera of dermatophytes causing superficial mycoses. These infections are on rise due to increase in immunocompromised patients and favorable environmental conditions in countries like India. The present study was undertaken to identify dermatophytes causing superficial fungal infection by microscopy and culture techniques which helps in accurate diagnosis and appropriate treatment of cases. Methodology and results: Samples were collected from affected sites after cleaning the affected surface with 70% alcohol. All samples were microscopically examined for presence of hyphal structures by digesting in 10% to 40% KOH solution. All samples were inoculated into Sabouraud dextrose agar with chloramphenicol and Sabouraud dextrose agar with cycloheximide and chloramphenicol and incubated at room temperature for four weeks. Tease mount technique and slide culture technique were used for identification of dermatophytes. One hundred and ten samples from clinically suspected dermatophytoses which includes 77(70%) from male and 33(30%) from female patients were processed for identification of dermatophytes. Samples were subjected to microscopy and culture. In 61 samples (54.54%) fungal hyphae were seen by direct microscopic examination (KOH). Fifty six samples (50%) yielded dermatophyte growth in culture. Trichophyton rubrum was the predominant species isolated followed by T. violaceum and T. mentagrophytes. Conclusion, significance and impact of study: Accurate and rapid diagnosis of superficial fungal infection is essential for proper management of cases. Direct microscopy is very good method for routine diagnosis, however culture remains gold standard.

Comparing the Effectiveness of Sabouraud Dextrose Agar and Dermatophytes Test Medium for Isolation of Dermatophytes.

Background: Dermatophytes affects more than 30% of the population, usually as superficial mycosis but also present as deeper subcutaneous tissue infection in rare occasions. Because of ambiguous clinical presentations of dermatophytosis need to diagnose accurately to avoid mismanagement. The present study was selected to know the significance of KOH (Potassium Hydroxide) in diagnosis of dermatophytosis and to compare Sabouraud Dextrose Agar (SDA) with Dermatophytes Test Medium (DTM) in isolation of dermatophytes. Methods: A total of 124 patients were included in this study who was diagnosed as clinically suspected dermatophytosis at Department of DVL. Samples were collected and inoculated in to Sabouraud Dextrose Agar with Chloramphenicol and Cycloheximide, Dermatophytes Test Medium and also KOH mount was done. Results: Out of 124 clinically suspected dermatophytosis studied population, 78 (62.9%) were culture positive. Tinea corporis (29.4%) was affected predominantly followed by Tinea cruris (21.7%) and Tinea capitis (17.9%). On correlation of culture positivity with KOH microscopy, 15 patients (12.09%) were culture positive and KOH negative. 12 (9.6%) patients out of 124 were KOH positive and culture negative. The isolation rate in this study from SDA was 93.5% and that of DTM was 100%. On comparing of dermatophytes isolation from clinical samples among DTM and SDA, shown statistically insignificant (P>0.05). Conclusion: KOH gives rapid probable diagnosis to start empirical therapy, lesser sensitive than culture media. Both SDA and DTM gives good isolation results, where as DTM is superior than SDA in isolation and aid in easy interpretation.

Is inclusion of Sabouraud dextrose agar essential for the laboratory diagnosis of fungal keratitis.

Purpose: To determine whether the inclusion of Sabouraud dextrose agar (SDA) is essential in the diagnosis of fungal keratitis. Materials and Methods: Corneal scrapings of 141 patients with microbial keratitis were smeared and cultured. Sheep blood agar (BA), chocolate agar (CA), SDA, non-nutrient agar (NNA) with Escherichia coli overlay, and brain heart infusion broth (BHI) were evaluated for time taken for growth and cost. The media were also evaluated experimentally for rate of growth and time taken for identification. Results: Twenty-six of 39 patients positive for fungus in corneal scrapings by microscopy were culture-positive. Fungus grew on BA in 22/39, on CA in 18/39, on SDA in 17/39, on NNA in 17/39, and on BHI in 13/39 cases. Growth on SDA was higher in ulcers with larger infiltrate (6/18 versus 9/13, P = 0.04). Estimated saving with inclusion of only BA/CA was Rs. 600 per patient. Performance of all media was similar in in vitro experiment although the characteristic spores and color were seen earlier on SDA. Conclusion: Fungal keratitis can be reliably confirmed on BA or CA, which support growth of both bacteria and fungus.

Screening of Fluconazole-Resistant Candida Species with Fluconazole-Containing Sabouraud Dextrose Agar Plates / 대한의진균학회지

BACKGROUND: Antifungal susceptibility testing methods are relatively expensive and laborious and are not easily applicable for screening purposes in routine laboratories. OBJECTIVE: We have developed a susceptibility screening method by adding fluconazole to Sabouraud dextrose agar (SDA) plate. In this study, SDA plates screening was compared with the Clinical and Laboratory Standards Institutes (CLSI) broth microdilution method for determining fluconazole susceptibility of Candida spp. METHODS: A total 186 isolates of Candida spp. (134 C. albicans, 24 C. tropicalis, 15 C. glabrata, 13 C. parapsilosis) were tested with the CLSI document M27-A2 method and fluconazole-containing SDA plate (0, 8, 16 microgram/mL of fluconazole). By this method, colony count and diameter were read after 24 hr of incubation. RESULTS: Fluconazole-susceptible Candida spp. are significantly smaller (> or =50%) on SDA with fluconazole than on fluconazole-free SDA. On SDA with 8 and 16 microgram of fluconazole per mL, 80.7% (150/186) and 87.1% (162/186) of isolates were correctly predicted, respectively. CONCLUSIONS: These data suggest that the fluconazole-containing SDA plates can be used as a routine screening procedure for susceptibility of Candida spp. in clinical laboratories.