Edgardo Chouela

Diagnosis and Treatment of Scabies

Scabies is a common, highly pruritic infestation of the skin caused by Sarcoptes scabiei var. Hominis. It is a very contagious parasitosis with specific lesions, such as burrows, and nonspecific lesions, such as papules, vesicles and excoriations. The typical areas of the body it affects are finger webs, wrists, axillary folds, abdomen, buttocks, inframammary folds and, in men, the genitalia. It is characterized by intense nocturnal pruritus. Scabies is spread through close personal contact (relatives, sexual partners, schoolchildren, chronically ill patients and crowded communities). Definitive diagnosis is made when the scabies mites or their eggs or fecal pellets can be identified on a light microscope. New techniques for diagnosis include the use of the epiluminiscence microscopy.The most common topical treatments for scabies include lindane and permethrin. Permethrin provides a greater margin of tolerability because of its low inherent toxicity and low percutaneous absorption. Oral ivermectin is the most recently developed treatment for scabies. A single oral dose of ivermectin 200 μg/kg of bodyweight is a well-tolerated and very effective treatment. It is especially indicated in crusted scabies, scabies in immunocompromised hosts and infestations in crowded communities. It is also useful as a simple treatment in the prophylaxis of close contacts.

The efficacy and safety of etanercept when used with as-needed adjunctive topical therapy in a randomised, double-blind study in subjects with moderate-to-severe psoriasis (the PRISTINE trial)

Abstract Objective: To assess the efficacy and safety of two etanercept dose regimens for psoriasis treatment. Methods: Subjects were ≥18 years old with stable moderate-to-severe plaque psoriasis. Subjects were randomised to etanercept 50 mg once weekly (QW) or 50 mg twice weekly (BIW) double-blind for 12 weeks, followed by 50 mg QW open label in all subjects through week 24. Only mild topical corticosteroids were permitted on scalp, axillae and groin for first 12 weeks; topical medications (corticosteroids of all potencies, vitamin D analogues and combination products) were allowed as needed for second 12 weeks at physicians discretion, consistent with “real-world” therapeutic practice. An independent ethics committee reviewed and approved the study protocol. Results: At week 24, 59.9% and 78.2% in the QW/QW and BIW/QW groups achieved PASI 75 improvement. Mean percentage PASI improvement in these groups was 58.5% and 74.1% at week 12 and 70.7% and 81.3% at week 24. Although permitted from weeks 12 to 24, topical agents were used in only 27.7% and 22.6% in the QW/QW and BIW/QW groups by week 24. Conclusion: Both etanercept regimens were efficacious in moderate-to-severe psoriasis, although the BIW/QW regimen consistently provided higher response rates than the QW/QW regimen. More potent topical medications were used electively in <25% of subjects in each group.

Head louse infestations: epidemiologic survey and treatment evaluation in Argentinian schoolchildren.

Background Our aim was to demonstrate that the treatment of individual cases is effective, but not sufficient, to control endemic Pediculus capitis, and that eradication of the epidemiologic school focus may lower significantly the prevalence of infestation. Statistical data on the degree of infestation relating to socio‐economic and cultural variables were also updated. Therapeutic effects and educational impact were evaluated.

HEPATITIS C VIRUS ANTIBODY (ANTI‐HCV): PREVALENCE IN PSORIASIS

Background. In cases of psoriasis (PS), the etiology of the underlying liver disease is occasionally unknown. To investigate antibodies to hepatitis C virus (anti‐HCV), their prevalence and clinical significance, 118 unselected outpatients with PS were studied prospectively.

Development of cutaneous sarcoidosis in a patient with chronic hepatitis C treated with interferon alpha 2b

Background: Sarcoidosis is a multisystemic granulomatous disorder of unknown etiology that most commonly affects young adults. A probable induction of sarcoidosis by interferons (IFN) has been published. To this date, few cases of cutaneous sarcoidosis in patients with chronic hepatitis C under interferon treatment have been reported. Objective: We describe a 50-year-old woman with chronic hepatitis C who developed lesions of cutaneous sarcoidosis three months after IFN treatment. Conclusions: The possible role of INF therapy in the development of cutaneous sarcoidosis in a patient with chronic hepatitis C should be considered.

Feasibility of daylight-mediated photodynamic therapy for actinic keratosis throughout the year in Central and South America: a meteorological study.

Daylight‐mediated photodynamic therapy (DL‐PDT) is an efficacious treatment option for thin actinic keratosis (AK) that offers advantages over conventional PDT in terms of tolerability, treatment duration, and cost. A clinical study conducted in Australia determined the mean irradiance during a 2‐hour exposure to be 305.8 W/m2 (range: 40–585 W/m2). The protoporphyrin IX light dose is influenced by latitude, weather conditions, and time of year. A recent study of meteorological data concluded that DL‐PDT can be performed effectively throughout the year in Australia.