India is witnessing an epidemic of dermatophytosis. The role of host immune response against fungi in chronicity and dissemination is topic of ongoing research. We conducted cross-sectional comparative study to determine the difference in Th1 (IFN-γ) and Th2 (IL4) response in serum and tissue between acute and localised vs. chronic and disseminated cases. Patients (18-60 years) were divided in two groups-group A (n=114, BSA <5%, single anatomic site, duration <6 months, n=118) and group B (n=107 BSA >10%, > one anatomic site, duration >12months, n=118). Clinical parameters along with serum levels of IgE, IL-4 and IFN-γ and expression of IL4 and IFN-γ in dermal infiltrate were compared between group. Trichophyton mentagrophytes complex was commonest causative fungi. Serum levels of IgE were significantly higher (median A-539.2, B-2901.0, p < .001) whereas levels IL-4(median A-21.3, B-20.4, p < .001) and IFN-γ(median A-9.6, B-5.1, p < .001) were significantly lower in chronic cases. Expression of IL-4 was observed in most biopsy specimens in both groups without any difference in intensity of staining. Expression of IFN-γ was not detected in all but one specimen across both the groups. Severe itching (OR:0.050, CI:0.018, 0.139, p < .001), sign of topical steroid abuse (OR:0.203,CI:0.077, 0.537; p=.001), ↓IFN-γ (OR:4.683, CI:1.634, 13.418; p=.004) correlated significantly and independently with chronic dermatophytosis. Our study shows chronic and disseminated cases of dermatophytosis differ immunologically in terms of higher IgE, and lower IL4 and IFN-γ. Expression of IL4 is present in tissue of both acute, localised and chronic disseminated cases. Expression of IFN-γ cannot be established in our study.
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