<p>Evaluation Of The Efficacy Of Fluorescent Staining And Chicago Sky Blue Staining As Methods For Diagnosis Of Dermatophytosis In Hair And Nails</p>

Abstract

PurposeDermatophytes are fungi that cause infections affecting hair, nail, and skin; in nails they cause onychomycosis, while in hair they lead to tinea capitis. Detection of dermatophytes using traditional methods, including potassium hydroxide (KOH) and culture on agar-based media leads to high rates of false-negative results. Here, we investigated more accurate diagnostic techniques, including Chicago sky blue staining and Calcofluor white fluorescent staining and compared them with traditional KOH and culture methods for the diagnosis of fungi causing onychomycosis and tinea capitis.Patients and methodsThis study was conducted using samples from 50 patients with dermatophytosis of the hair or nail. Samples were subjected to all the following laboratory investigations: KOH wet mount, culture on Sabouraud’s dextrose agar, Chicago sky blue staining, and Calcofluor white staining. The results of the new diagnostic techniques were compared with those of the traditional methods.ResultsCalcofluor white stain and Chicago sky blue stain for dermatophytosis of hair and nail are more specific and sensitive as compared to traditional diagnostic methods. KOH wet mount is simple, rapid, and inexpensive test but lacks color contrast and gave more false positive (artifacts) and false-negative results as compared to these new stain methods.ConclusionChicago sky blue and Calcofluor white staining are excellent methods for diagnosis of fungal infections, including those that cannot be confirmed using conventional methods.

Clinico-mycological study of dermatophytosis among diabetic and non-diabetic patients in a tertiary level hospital – a comparative study

“…18 In our study, fungal culture was taken as the gold standard for statistical analysis and the diagnostic parameters of KOH and Calco uor white staining were compared with culture. The sensitivity of the Calco uor white stain in the diagnosis of dermatophytosis has been reported to be higher than that of KOH mount by other authors like Mourad et al, 19 Attal et al, 20 Shwetha et al, 21 and Dass et al 22 Similar to these studies, Calco uor white staining had a speci city of 97.06%…”

Recent trends in rapid diagnostic techniques for dermatophytosis

“…Several studies and experiments have been tried on a different clarifying agent, during wet slide preparation, to achieve a better cleared microscopic view and less time during the slide preparation and examination. Potassium hydroxide (KOH), sodium hydroxide (NaOH), calcofluor white [11], Chicago sky blue [12], lactophenol cotton blue (LPCB), and a mixture of dimethyl sulphoxide (DMSO) and glycerine with NaOH or KOH.…”

“…The main obstacle facing the natural fluorescence-based dermatophytes technique is this nature's limitation to a few species leads to overall independence on this technique in dermatophytes diagnosis. On the other hand, using a fluorescent dye as calcofluor white showed significant advances in conventional KOH wet mount [12].…”

Deep convolutional neural networks for onychomycosis detection using microscopic images with KOH examination

“…In a study, its sensitivity and specificity values for the diagnosis of onychomycosis have been reported as 97% and 93%, respectively. 7 Compared to other methods, KOH examination is more practical and cheaper. However, it suffers from unreliable diagnostic performance due to dependence on the clinician experience.…”

“…Fluorescent microscopy with Calcofluor White stain is another diagnostic option for the detection of fungal elements. In a study, its sensitivity and specificity values for the diagnosis of onychomycosis have been reported as 97% and 93%, respectively 7 . Compared to other methods, KOH examination is more practical and cheaper.…”