Evaluation of a newly-developed immunochromatography strip test for diagnosing dermatophytosis.

Background: Traditionally, dermatophytosis, a common disease affecting millions of people world-wide, has been diagnosed by direct microscopy and fungal culture. The immunochromatography (ICG) strip test was recently developed.

Methods: We compared the performance of the ICG strip test for the detection of dermatophytes in samples from human skin and nails with direct microscopy. The 160 samples, consisting of 88 skin and 72 nail specimens, were subjected to direct microscopy study using a 20% KOH solution and to examination with the ICG strip test. Of 160 samples, 18 were examined by fungal culture using Sabouraud dextrose agar medium.

Results: We found that the overall sensitivity and specificity of the ICG test were 83.5% and 66.7%; they were 82.1% and 76.2% for the 88 skin and 85.4% and 58.3% for the 72 nail specimens, respectively.

Conclusions: Our findings indicate that the efficacy of the ICG test is comparable to direct microscopy for the detection of dermatophytes. Performance of the assay was easy, and results were available quickly. We suggest that it is an effective tool for dermatophytosis screening.