Phenotyping And Genotyping Identification Of Important Human, Animal And Soil Of Dermatophytes

In the current study, 62 dermatophyte isolates obtained from human and animal dermatophytosis as well as from soil were subjected for phenotypic and genotypic identification. The conventional (phenotypic) method for identification of dermatophytes in the present work was succeeding to identify all isolates through macro-morphology, micro-morphology and differential media into species. Identification of 48 isolates obtained from human cases revealed 15 M.canis, 12 T. violaceum, 12 T. rubrum, 5 E. fluccosum and 4 T. mentagrophytes. The eight isolates obtained from cattle were identified as T. verrucosum, while the four isolates obtained from dogs and cats were identified as M. canis. On the other hand, two dermatophyte isolates obtained from soil were identified as M. gypseum. On the other hand, three methods were used for molecular (genotypic) identification of dermatophytes which include: a) PCR for amplification of ITS1 and ITS4 followed by restriction fragment length polymorphism (RFLP) using MvaI for 30 isolates of dermatophyte formerly identified by phenotypic method, b) Application of PCR using single repetitive oligonucleatede (GACA) 4 for 30 dermatophyte isolates formerly identified by phenotypic and RFLP methods, c) DNA sequencing which done  for 5 representative isolates of M.canis, T.verrucosum, T.violaceum and T.rubrum. While, RFLP using Mval method and repetitive(GACA) 4 method identified the 30 dermatophyte isolates into species identical to those identified by phenotypic methods, sequencing identified one isolate formerly identified by phenotypic, MvaI and (GACA) as T. rubrum with similarity 99% as T. raubitschekii. Although molecular methods are rapid and represents technological advance in the laboratory diagnosis, it is expensive. So, we recommended its use in absence of skilled mycologist in identification of atypical or variants of dermatophyte species.