KONCPA Findings of Onychomychotic Nail Samples Where Non-dermatophytic Fungi were Cultured

Kang, Bong Seon; Park, Hyun Jung; Lee, Jun Young; Cho, Baik Kee

Abstract

BACKGROUND: When Candida species and molds (non-dermatophytic filamentous fungi) are cultured from the onychomycotic nail samples, it is sometimes difficult to consider whether they are the causative fungi or not. Although repeated culture is the most effective method to solve the problem, it is time-consuming and not cost-effective. But KONCPA (KOH + Nail clipping + PAS stain) is an inexpensive, quick, sensitive and very useful supportive test for considering whether the cultured non-dermatophytic fungi are real causative fungi or not.
OBJECTIVES
This study was aimed to know whether KONCPA test would increase the diagnostic sensitivity of onychomycosis and whether KONCPA findings would be of help to diagnose the accurate causative fungi in case where the Candida species and molds were cultured.
METHODS
Nail saacmples were obtained from 213 patients with onychomycosis for fungus culture and KONCPA test. And the KONCPA findings were reviewd for the onychomycotic nail samples where the non-dermatophytic fugi such as Candida species and molds were cultured.
RESULTS
The results of this study were summarized as follows: 1. From 93 onychomycotic nail samples, dermatophytes were cultured in 24 (11.3%), Candida spp. in 36 (16.9%), and molds in 33 samples (15.5%). 2. Of the 36 samples where the Candida spp. were cultured, 24 (66.7%) showed findings of dermatophytes, 2 (5.6%) of Candida spp. and remaining 10 (27.7%) samples were inadequate for diagnosis. 3. Of 33 samples where the molds were cultured, 30 (90.9%) showed findings of dermatophytes, 1 (3.0%) of molds and remaining 2 (6.1%) samples were inadequate for diagnosis.
CONCLUSIONS
Among 93 onychomycotic nail samples where the non-dermatopytic fungi were cultured, only 3 samples were compatible with KONCPA findings. Therefore, in cases where Candida spp. and molds were cultured and the KONCPA findings were not compatible with the cultured fungi, the cultured fungi should not be considered as the definite causative fungi until other material evidence was obtained.