Comparison of Dermoscopic Findings of Chronic Hand Eczema and Palmoplantar Psoriasis: A Cross-sectional Study

Abstract

Introduction: Differentiation between Chronic Hand Eczema (CHE) and Palmoplantar Psoriasis (PP) is a diagnostic challenge. Dermoscopy can helpto distinguish between the two conditions. Aim: To establish and compare the dermoscopic findings of the CHE and PP using DermLite DL4 dermoscope and to confirm the accuracy of the dermoscopic findings with the histopathological findings. Materials and Methods: A cross-sectional study was conducted at Navodaya Medical College, Hospital and Research Centre, Raichur, Karnataka, India, from January 2017 to June 2018. Fifty patients each of CHE (26 male and 24 female subjects) and PP (25 male and 25 female subjects) were included in the study. A detailed clinical history, cutaneous clinical and dermoscopic findings of each case were noted. A 4 mm punch biopsy was taken from 30 patients for histopathological analysis. The data was tabulated, analysed and tested for significance using the Chi-square test. Results: The mean age of the patients was 46±4 years. On dermoscopic examination, diffuse white scales in 45 (90%) patients, over a red background in 49 (98%) patients with regularly arranged dots and globules in 45 (90%) patients was seen in PP. Patchy yellow scales 46 (90%), yellow dots, globules and yellow to brown crusts against a yellow background was seen in all patients (100%) of CHE (p-value <0.001). Histopathological findings are in agreement with dermoscopic findings in 9/16 and 10/14 cases of CHE and PP respectively. Conclusion: Dermoscope is a useful non invasive clinical aid to differentiate between CHE and PP. The presence of diffuse white scales over a red background and regularly arranged vessels indicates PP, whereas the presence of patchily distributed yellow scales, yellow dots and globules; and yellow to brown crusts against a yellow background is more suggestive of CHE.