[Scabies finally getting the attention it merits!]

[Main parasitic skin disorders]

Cutaneous parasitic skin diseases are frequent in human pathology. There are few reliable epidemiological data on the prevalence and/or incidence of such diseases. Skin parasites are cosmopolitan but their global distribution is heterogenous; prevalence is especially high in subtropical and tropical countries. They are mainly due to arthropods (insects and mites). Many species of parasites are involved, explaining the diversity of their clinical signs. The most common are caused by ectoparasites such as scabies or pediculosis (head lice, body lice and pubic lice). Clinical signs may be related to the penetration of the parasite under the skin, its development, the inoculation of venom or allergic symptoms. Diagnosis can be easy when clinical signs are pathognomonic (e.g. burrows in the interdigital web spaces in scabies) or sometimes more difficult. Some epidemiological characteristics (diurnal or nocturnal bite, seasonality) and specific clinical presentation (single or multiple bites, linear or grouped lesions) can be a great diagnostic help. Modern non-invasive tools (dermoscopy or confocal microscopy) will play an important role in the future but the eye and experience of the specialist (dermatologist, parasitologist, infectious disease specialist or entomologist) remains for the time the best way to guide or establish a diagnosis. For most skin parasites, therapeutic proposals are rarely based on studies of high level of evidence or randomized trials but more on expert recommendations or personal experience.

[Severe crusted scabies: A "historic" case involving the death of a 52-year-old patient]

BACKGROUND

Crusted scabies, also known as Norwegian scabies, is a rare and extremely debilitating form of Sarcoptes scabiei var. hominis infestation that generally occurs in immunosuppressed patients. Herein, we report a "historic" and fatal case.

PATIENTS AND METHODS

A 52-year-old woman was admitted to the emergency department presenting crusted dermatitis together with extreme deterioration of her general condition. Her general practitioner had initiated dermo-corticosteroid therapy for suspected atopic dermatitis two months earlier, and she had been confined to bed for the previous 10 days. Her son presented pruritus that became worse at night. On examination the patient was moaning, dehydrated and confused and her entire skin was hyperkeratotic, with very thick, yellowish, cracked crusts covering 40 % of her body. Tests indicated severe water and electrolytic disorders as well as Staphylococcus aureus bacteremia. A tape test established the diagnosis of crusted scabies. The severity was grade III on the Davis clinical grading scale. The patient showed signs of multi-organ failure and was transferred to intensive care, but she died during the night.

DISCUSSION

This case is remarkable for its historic severity. In France, scabies infestation is a re-emerging disease and has been a public health priority since 2012. The rare hyperkeratotic form is not fully understood and frequently diagnosed late, in some cases with a fatal outcome.

Features of human scabies in resource-limited settings: the Cameroon case

Background

The persistent high prevalence of human scabies, especially in low- and middle-income countries prompted us to research the sociodemographic profile of patients suffering from it, and its spreading factors in Cameroon, a resource-poor setting.

Methods

We conducted a cross-sectional survey from October 2011 to September 2012 in three hospitals located in Yaoundé, Cameroon, and enrolled patients diagnosed with human scabies during dermatologists’ consultations who volunteered to take part in the study.

Results

We included 255 patients of whom 158 (62 %) were male. Age ranged from 0 to 80 years old with a median of 18 (Inter quartile range: 3–29) years. One to eight persons of our patients’ entourage exhibited pruritus (mean = 2.1 ± 1.8). The number of persons per bed/room varied from 1 to 5 (mean = 2.1 ± 0.8). The first dermatologist’s consultation occurred 4 to 720 days after the onset of symptoms (mean = 77.1 ± 63.7). The post-scabies pruritus (10.2 % of cases) was unrelated to the complications observed before correct treatment (all p values > 0.05), mainly impetiginization (7.1 %) and eczematization (5.9 %).

Conclusion

Human scabies remains preponderant in our milieu. Populations should be educated on preventive measures in order to avoid this disease, and clinicians’ knowledges must be strengthened for its proper diagnosis and management.