Pédérose ou dermatite à Paederus : quatre observations en Provence

Literature review of the causes, treatment, and prevention of dermatitis linearis

BACKGROUND

Dermatitis linearis is a skin condition that affects both local populations and travelers alike. Dermatitis linearis is caused by some beetles within the subtribe Paederina and manifests as painful lesions, blisters and intense itching. Though outbreaks are widespread, the condition as a whole still remains relatively unknown.

METHODS

An extensive search of the existing Paederus literature was conducting in order to elucidate relevant information regarding the occurrence of outbreaks, seasonality, exposure and symptom onset, and management of dermatitis linearis. Special consideration was given to behavioral and environmental factors.

RESULTS

Epidemics of dermatitis linearis are most commonly observed during the rainy season or after particularly hot and humid weather patterns. Symptom onset is typically delayed 6-48 h after exposure. The most common symptoms are stinging, burning and itching, with later development of erythematous plaques and blisters. Though symptoms of dermatitis linearis resolve spontaneously, wet compresses, antihistamines and topical steroid ointments and lotions are recommended to alleviate symptoms.

CONCLUSIONS

Dermatitis linearis in travelers and local populations can be prevented through minimizing or modifying sources of artificial light, using pesticide-treated nets near beds and lights, general housekeeping and vegetation maintenance, and by raising awareness regarding the conditions caused by Paederus.

[Vesicular contact dermatitis due to Paederus in Cameroon and review of the literature]

This irritant blister dermatitis is caused by the genus Paederus whose geographical distribution is worldwide, with a higher incidence in tropical areas. It is induced by direct skin contact with pederin, a blistering and caustic substance found in the abdomen (coelome) of Paederus insects (insect order Coleoptera: family Staphylinidae). The diagnosis is based on the presence of typical clinical features combined with compatible epidemiological features. Our goal is to describe the epidemiological and clinical features of this irritant contact dermatitis in Cameroon through a retrospective study conducted at the end of the rainy season at the Oku Hospital in Northwest Cameroon and to also include cases reported at the medical center of the French Embassy in Yaounde during this same timeframe. In addition, we conducted a literature review of paederus dermatitis. Nineteen patients were included in this study. More than half of the patients presented with more than two lesions predominantly localized to the face or the neck; less than half had complications manifesting as either localized or respiratory reactions and three patients presented periorbital involvement. This study confirms the presence of paederus dermatitis in Cameroon. It is mainly localized in the unusual geoclimatic region of the western high mountains within the country, as well as the usual warm, moist areas of Yaounde. The clinical evolution of this dermatitis is usually one of spontaneous and uneventful resolution with complications being rare. Curative treatment is one of localized topical therapies while oral antibiotic therapy should be reserved for more complicated cases.

Paederus Outbreaks in Human Settings: A Review of Current Knowledge

Although rove beetles (Paederus spp.) play a beneficial role as biological control agents to manage crop pests in agro-ecosystems, their high prevalence in human settings has elevated them to pest status in urban areas. Rove beetles neither bite nor sting, but accidental crushing on human skin causes them to release the toxin paederin, which causes dermatitis linearis. This review integrates currently available knowledge about the issues pertaining to Paederus infestation. For instance, the results of life history studies conducted under different food and temperature regimes are summarized, as they indicate how large a population can be in a habitat to cause massive and widespread infestation and illustrate the physiological traits required to maintain the population at the maximum level even under adverse conditions. In contrast to what is generally reported, we speculate that climatic factors do not necessarily result in Paederus dispersal in temperate regions; instead, habitat disturbance and site unsuitability may be the main factors that lead to massive dispersal to human settings. Factors such as whether dispersers are adaptable to xeric conditions in human settings, the probability that dispersed Paederus mate with the opposite sex, and whether dispersers have adequate nutrient intake to reproduce are considered to evaluate their potential to reproduce in human settings. Finally, the effectiveness of current commercial insecticides, challenges faced in managing infestations, and sustainable management practices are discussed to provide information for long-term control programs.