The PAS Stain for Routine Diagnosis of Onychomycosis

The percentage of positivity of combined PAS and culture was 79 (56%) and combined KOH and culture was 64 (45.4%), (Table 2). Comparing PAS test alone as an alternative method of diagnosis to combined KOH and culture (for both culture positive and culture negative cases) showed an overall sensitivity of 60.9% and specificity of 80.3%. When applied specifically to dermatophyte culture positive cases (N=28), the PAS was found to have a sensitivity of 92.9%, compared to 23% for non-dermatophyte positive culture cases (N=30).