Paederus dermatitis' outbreak in residential hostels – A retrospective clinical study

Introduction: Paederus dermatitis is an acute irritant dermatitis caused by accidental crushing of an insect belonging to the genus Paederus, releasing the vesicant pederin. It is commonly seen in the rainy season, especially in tropical regions. Methods: The aim of this study is to analyze the epidemiological and clinical findings of paederus dermatitis and factors associated with this condition in patients attending the dermatology, venereology and leprosy (DVL) department at a tertiary care hospital. This is a 3-year retrospective study from November 2016 to December 2019. This study was undertaken as a large number of cases with similar complaints attended D.V.L outpatient department during the same period (November–January) in 3 consecutive years. A total of 120 girls clinically diagnosed with paederus dermatitis residing in residential girls' hostels were included in the study. All the cases were evaluated using a standard pro forma which included a detailed history and clinical examination. All the patients were treated appropriately and control measures were advised to prevent further attacks. Patients were followed up until the lesions healed for 2 weeks. Results: Age of the children ranged from 10 to 16 years. The mean age of patients was 13.4 years. The majority of the cases were reported in November (57) and December (42) for 3 consecutive years and the remaining cases were observed randomly during the study period. Most of the patients presented within 48–96 h of lesion onset. The chief complaints were redness of the skin with itching and burning. The most common presentation was widespread erythema, edema, erosions, and desquamation involving larger areas, not localized which is uncommon with paederus dermatitis. Facial involvement is significant and observed in 99 (82.5%) cases. In addition to the face, other sites affected were the neck in 82 (68.3%), forearms in 41 (34.16%), and upper trunk in 30 (25%) patients. Constitutional symptoms although mild were reported in 3% of patients. Conclusion: An atypical variant of paederus dermatitis was observed in the majority of the cases with diffuse erythematous and desquamative lesions predominantly involving the face and neck. A careful history and awareness about varied clinical features will help in early diagnosis and to undertake preventive measures.