Diagnostic Challenge Of Paederus Dermatitis Mimicking Herpes Zoster In The Tropics: A Case Report

Abstract

The clinical similarity between paederus dermatitis and herpes zoster often poses a diagnostic challenge in tropical regions, frequently leading to inappropriate initial management. This study aims to document a medical case to provide clinical insights into differentiating these two conditions, particularly in settings with limited diagnostic facilities. The method used is qualitative with a case study design to analyze the presentation and management of a patient at the Dermatology and Venereology Outpatient Clinic of Mataram University Hospital. A 14 year old male boarding school student presented with a five day history of sudden, burning erythematous lesions on his back, which had been previously misdiagnosed as herpes zoster by a general practitioner. General physical examination showed normal vital signs and a good general condition. Dermatological examination of the posterior thoracic region revealed well-demarcated erythematous plaques with characteristic elongated linear whip like marks on the left and central back, accompanied by vesicles, erosions, and thin crusts. No laboratory or cytological examinations were performed. Based on the distinctive whip like morphology and an epidemiological history of similar complaints among his dormitory friends, the diagnosis was corrected to Paederus dermatitis. The patient was treated with topical corticosteroid therapy using hydrocortisone 1% cream applied thinly twice daily as the initial treatment. In conclusion, this case highlights that comprehensive environmental history taking and careful assessment of lesion morphology are essential to establish an accurate diagnosis, prevent unnecessary medication use, and ensure appropriate treatment.