Paederus Dermatitis: Environmental Risk Factors, Clinical Features, and Management

Abstract

Paederus dermatitis (spider lick, night burn, blister beetle dermatitis, or dermatitis linearis) is a form of irritant contact dermatitis (ICD) that is characterized by a sudden onset of erythematobullous lesions on exposed body areas. This skin disorder is caused by a beetle of the genus Paederus. A number of environmental factors have been reported to be associated with Paederus dermatitis, including artificial lights, crop harvest, and dispersal of Paederus beetles and climate influence. Skin lesions and symptoms develop within 6–48 h after a contact with pederin, a toxic substance that is released after crushing the insect against the body; they include skin burning and stinging (generally precede other symptoms), itching, erythematous plaques, edema, vesicles, and/or blisters. Paederus dermatitis can be prevented by applying a series of measures such as avoidance of sitting under artificial light sources during seasons of P. dermatitis outbreaks, avoidance of crushing Paederus beetle against the skin (blow it off instead of crushing it), closing doors and windows at night during the season of outbreak, careful use of insecticides to reduce Paederus beetle population in the living environment (but avoid contamination of the environment), removal of vegetation near residential buildings and houses, and the use of light sources that less attract insects, if possible. Washing the affected body area with soap and clean water and the application of cold wet compresses, after skin contact with pederin, may reduce the risk of developing skin lesions. On the other hand, an oral antibiotherapy can be envisaged in case of infection.