Diagnostic Dilemma: Psoriasis and Psoriasiform Dermatitis - A Clinicohistopathological Correlation Study in a Tertiary Care Centre, Chennai.

Background: Psoriasis and related disorders are a group of common, chronic, inammatory and proliferative conditions of the skin, associated with systemic manifestations. Psoriasiform dermatitis comprises of a wide variety of diseases that resemble psoriasis both at clinical and histological levels. This group includes Seborrheic Dermatitis, Pityriasis Rubra Pilaris, Allergic Dermatitis, Atopic Dermatitis, Nummular Eczema, Lichen Simplex Chronicus, Pityriasis Rosea, Dermatophytosis,Mycosis Fungoides,Psoriasiform Syphilide etc.These patients often prove to be a diagnostic dilemma for the clinician and warrant a histopathological conrmation. Materials and Methods: We conducted a retrospective study among patients who had attended our Dermatology OPD from March 2023 to January 2024. The records of patients who were clinically diagnosed as psoriasis and psoriasiform dermatitis were collected, data extracted and categorised into different groups. The clinical and pathological correlation of psoriasis and psoriasiform dermatitis were done. Descriptive statistics of the obtained data were calculated. Results: Out of the 50 patients included in the study, majority were females(52%) belonging to the age group of 40-50 years(60%). Psoriasis was the most common disease according to clinical as well as histological diagnosis. In this study, majority of patients (58%) had been clinically diagnosed as psoriasis and rest 42% patients were clinically diagnosed as psoriasiform dermatitis. Histological diagnosis of psoriasis had been made in 44% of patients. Conclusion: Psoriasis could be confused with other dermatological diseases having similar presentations (psoriasiform dermatitis), thus complicating the diagnosis. Hence, it is histopathological examination that eventually helps in aiding diagnosis and makes it imperative to perform a skin biopsy in suspected cases.