Demodex folliculorum infestations in common facial dermatoses: acne vulgaris, rosacea, seborrheic dermatitis

Abstract Background: Demodex mites are found on the skin of many healthy individuals. Demodex mites in high densities are considered to play a pathogenic role. Objective: To investigate the association between Demodex infestation and the three most common facial dermatoses: acne vulgaris, rosacea and seborrheic dermatitis. Methods: This prospective, observational case-control study included 127 patients (43 with acne vulgaris, 43 with rosacea and 41 with seborrheic dermatitis) and 77 healthy controls. The presence of demodicosis was evaluated by standardized skin surface biopsy in both the patient and control groups. Results: In terms of gender and age, no significant difference was found between the patients and controls (p > 0.05). Demodex infestation rates were significantly higher in patients than in controls (p = 0.001). Demodex infestation rates were significantly higher in the rosacea group than acne vulgaris and seborrheic dermatitis groups and controls (p = 0.001; p = 0.024; p = 0.001, respectively). Demodex infestation was found to be significantly higher in the acne vulgaris and seborrheic dermatitis groups than in controls (p = 0.001 and p = 0.001, respectively). No difference was observed between the acne vulgaris and seborrheic dermatitis groups in terms of demodicosis (p = 0.294). Study limitations: Small sample size is a limitation of the study. The lack of an objective scoring system in the diagnosis of Demodex infestation is another limitation. Conclusion: The findings of the present study emphasize that acne vulgaris, rosacea and seborrheic dermatitis are significantly associated with Demodex infestation. Standardized skin surface biopsy is a practical tool in the determination of Demodex infestation.

Dermatoscopic signs in cutaneous leishmaniasis

Abstract: Dermoscopy is a non-invasive technique widely used to aid in the characterization and diagnosis of pigmented skin lesions. Recently, it has also been employed for the evaluation of non-pigmented skin tumours, and inflammatory and infectious cutaneous diseases. Although the diagnosis of cutaneous leishmaniasis is confirmed by the demonstration of amastigotes in infected skin or by the growth of promastigotes in culture medium, dermoscopy could be useful as a further diagnostic test. We report a patient with a nodular lesion located on the right cheek for almost two years. The lesion was clinically suggestive of cutaneous leishmaniasis. Dermoscopy showed yellow tears, erythema and vascular structures. The diagnosis was confirmed by the demonstration of amastigotes in a skin scraping sample.

Excision of furuncular myiasis larvae using a punch: a simple, practical and aesthetic method

Abstract: Myiasis refers to Diptera larvae infesting vertebrate animals. There are two forms of the disease: primary and secondary. In primary myiasis, fly larvae invade and develop in healthy tissue; in secondary myiasis, flies lay their eggs in skin ulcerations, and the larvae develop in tissue necrosis products. Furuncular myiasis is a type of primary myiasis. Treatment for it consists of techniques such as the production of localized hypoxia to force the emergence of the larvae, and mechanical or surgical removal of the maggots. These techniques, however, are painful and often unsuccessful. We propose a new technique for extraction of myiasis larvae, which might facilitate the surgical procedure and constitute a virtually painless and aesthetic option for the patient.

Is Demodex really non-pathogenic?

Although usually considered a non-pathogenic parasite in parasitological textbooks, Demodex folliculorum has been implicated as a causative agent for some dermatological conditions, such as rosacea-like eruptions and some types of blepharitis. Several anecdotal reports have demonstrated unequivocal tissue damage directly related to the presence of the parasite. However, this seems to be exceedingly rare, in contrast with the marked prevalence of this infestation. We have had the opportunity to observe one of such cases. A 38-year-old woman presented with rosacea-like papular lesions in her right cheek. Histopathological examination revealed granulomatous dermal inflammation with a well-preserved mite phagocytized by a multinucleated giant cell. This finding may be taken as an evidence for the pathogenicity of the parasite, inasmuch as it does not explain how such a common parasite is able to produce such a rare disease.

Um caso de leishmaniose cutâneo-mucosa tratado com sucesso com baixa dose de antimonial pentavalente / A case of mucocutaneous leishmaniasis treated with success with a low dose of pentavalent antimonial

Os autores relatam um caso de leishmaniose cutâneo-mucosa em uma paciente de 89 anos, diabética e hipertensa, tratada inicialmente com alopurinol por 10 meses não havendo cicatrização das lesões. Posteriormente, recebeu antimoniato de N-metil glucamina (glucantime) por 4 dias, na dose total de 2.380mg do Sbv, mas desenvolveu cardiotoxicidade e hipocalemia, sendo suspenso o tratamento, entretanto, evoluiu com regressão clínica total das lesões, apesar de ter recebido pequena dose desta medicação.

The authors report a case of a 89 years-old woman with mucocutaneous leishmaniasis and previous diabetes mellitus and high blood pressure, who had been treated with allopurinol for 10 months without healing of lesions. Afterwards, she has been treated with meglumine antimonate, [quot ]glucantime[quot ] for 4 days, with a total dose 2,380 mg of Sbv, but developed cardiac side effects and hypokalemia, hence the treatment was withdrawn. However, this patient developed total clinical regression of lesions, in spite of she has been received low dose of this drug.