The current Indian epidemic of superficial dermatophytosis due to Trichophyton mentagrophytes-A molecular study

Mycoses. 2019 Apr;62(4):336-356. doi: 10.1111/myc.12878. Epub 2019 Feb 20.

Abstract

The disease burden of chronic-relapsing and therapy-refractory superficial dermatophytosis dramatically increased in India within the past 5-6 years. In order to evaluate the prevalence of this trend, 201 skin scrapings were collected from patients from all parts of India and were tested for dermatophytes using both fungal culture and a PCR-ELISA directly performed with native skin scrapings. Fungal culture material was identified by genomic Sanger sequencing of the internal transcribed spacer (ITS) region and the translation elongation factor (TEF)-1α gene. In total, 149 (74.13%) out of the 201 samples showed a dermatophyte-positive culture result. Out of this, 138 (92.62%) samples were identified as Trichophyton (T.) mentagrophytes and 11 (7.38%) as Trichophyton rubrum. The PCR-ELISA revealed similar results: 162 out of 201 (80.56%) samples were dermatophyte-positive showing 151 (93.21%) T mentagrophytes- and 11 (6.79%) T rubrum-positive samples. In this study, we show for the first time a dramatic Indian-wide switch from T rubrum to T mentagrophytes. Additionally, sequencing revealed a solely occurring T mentagrophytes "Indian ITS genotype" that might be disseminated Indian-wide due to the widespread abuse of topical clobetasol and other steroid molecules mixed with antifungal and antibacterial agents.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Child, Preschool
  • DNA, Fungal / chemistry
  • DNA, Fungal / genetics
  • DNA, Ribosomal Spacer / chemistry
  • DNA, Ribosomal Spacer / genetics
  • Enzyme-Linked Immunosorbent Assay
  • Epidemics*
  • Female
  • Humans
  • India / epidemiology
  • Male
  • Middle Aged
  • Molecular Epidemiology
  • Peptide Elongation Factor 1 / genetics
  • Polymerase Chain Reaction
  • Prevalence
  • Sequence Analysis, DNA
  • Tinea / epidemiology*
  • Trichophyton / classification*
  • Trichophyton / genetics
  • Trichophyton / isolation & purification*
  • Young Adult

Substances

  • DNA, Fungal
  • DNA, Ribosomal Spacer
  • Peptide Elongation Factor 1

Associated data

  • GENBANK/MH791418
  • GENBANK/MH802489
  • GENBANK/MH791419
  • GENBANK/MH802490
  • GENBANK/MH791420
  • GENBANK/MH802491
  • GENBANK/MH791421
  • GENBANK/MH802492
  • GENBANK/MH791422
  • GENBANK/MH802493
  • GENBANK/MH791423
  • GENBANK/MH802494
  • GENBANK/MH791424
  • GENBANK/MH802495
  • GENBANK/MH791425
  • GENBANK/MH802496
  • GENBANK/MH791426
  • GENBANK/MH802497
  • GENBANK/MH791427
  • GENBANK/MH802498
  • GENBANK/MH791428
  • GENBANK/MH802499
  • GENBANK/MH791429
  • GENBANK/MH802500
  • GENBANK/MH791430
  • GENBANK/MH802501
  • GENBANK/MH791431
  • GENBANK/MH802502
  • GENBANK/MH791432
  • GENBANK/MH802503
  • GENBANK/MH791433
  • GENBANK/MH802504
  • GENBANK/MH791434
  • GENBANK/MH802505
  • GENBANK/MH791435
  • GENBANK/MH802506
  • GENBANK/KT192468