Utility of Dermoscopy in the Diagnosis of Erythroderma: A Cross-Sectional Study.

Background: It is difficult to diagnose the underlying cause of erythroderma on mere clinical presentation. The role of dermoscopy in diagnosing erythroderma secondary to various etiologies is evolving. Aim and Objectives: This study aimed to observe the dermoscopic features of erythroderma secondary to different cutaneous disorders and compare them with clinical features and histopathology. Materials and Methods: Twenty-nine consecutive patients of erythroderma were enrolled in the study. Dermoscopy was performed on every case using a Heine Delta II Dermatoscope with 10x magnification in polarized mode. A histopathological examination was conducted to confirm the diagnosis. Results: Eight patients were diagnosed with psoriasis, five with endogenous eczema, four with pityriasis rubra pilaris (PRP), three with pustular psoriasis, two with drug rash secondary to antitubercular therapy, two with dermatophytic infection, one patient each of atopic dermatitis, crusted scabies, pemphigus foliaceous, drug reaction with eosinophilia and systemic symptoms, and mycosis fungoides. Characteristic dermoscopic features were observed in erythroderma due to psoriasis, PRP, pustular psoriasis, endogenous eczema, scabies, and dermatophytosis. Differentiation of other disorders based on dermoscopy alone was difficult, and clinico-histopathological correlation was crucial to reach a diagnosis. Conclusion: Dermoscopic features of classical patterns of skin disorders are preserved even in the corresponding erythrodermic or unstable stage. Dermoscopic features of erythroderma secondary to psoriasis, pustular psoriasis, PRP, endogenous eczema, scabies, and dermatophytosis are clearly differentiating, whereas the dermoscopic features in other causes of erythroderma are overlapping. Thus, dermoscopy can be a good screening tool in the clinical assessment of erythroderma.