Ivermectin versus benzyl benzoate applied once or twice to treat human scabies in Dakar, Senegal: a randomized controlled trial.

OBJECTIVE: To compare the effectiveness of oral ivermectin (IV) and two different modalities of topical benzyl benzoate (BB) for treating scabies in a community setting. METHODS: The trial included patients aged 5-65 years with scabies who attended the dermatology department at the Institut d'Hygiène Sociale in Dakar, Senegal. The randomized, open trial considered three treatments: a single application of 12.5% BB over 24 hours (BB1 group), two applications of BB, each over 24 hours (BB2 group), and oral IV, 150-200 microg/kg (IV group). The primary endpoint was the disappearance of skin lesions and itching at day 14. If necessary, treatment was repeated and patients were evaluated until cured. Results were analysed on an intention-to-treat basis. A pre-planned intermediate analysis was carried out after the BB1, BB2 and IV groups had recruited 68, 48 and 65 patients, respectively. FINDINGS: At day 14, 33 patients (68.8%) in the BB2 group were cured versus 37 (54.4%) in the BB1 group and 16 (24.6%) in the IV group (P < 10-6). Bacterial superinfection occurred more often in the IV group than in the BB1 and BB2 groups combined (28% versus 7.8%, respectively; P = 0.006). At day 28, 46 patients (95.8%) in the BB2 group were cured versus 52 (76.5%) in the BB1 group and 28 (43.1%) in the IV group (P < 10-5). These clear findings prompted early study cessation. CONCLUSION: Topical BB was clearly more effective than oral IV for treating scabies in a Senegalese community.

[Skin disease in Koranic schools in Dakar (Senegal)]. / La prevalence des dermatoses dans les ecoles coraniques a Dakar (Senegal).

The koranic schools are in poor socio-economical conditions in Dakar and skin diseases are common in these conditions. The goal of our descriptive study was to determine the prevalence of skin diseases occurring in these situations. One hundred five boys from four koranic schools of Dakar were examined. Eighty percent of the examined boys were with unless one skin disease. Tinea capitis (42.66%), scabiosis (13.33%), pyoderma (15.33%), plantar keratodermia (100%) were the skin diseases. In 34.52% these skin disease were associated and antecedents of skin infections diseases were reported in 89.5% of boys. Atopic dermatitis was in 2.38% cases, keloid in 1.19%. The other frequent diseases were abdominal parasitosis (71.42%), umbilical hernia (6.66%). All skin diseases were improved only in 50% of cases after two months of treatment. Tinea capitis was cured in 4 months after treatment. The high prevalence and the chronicity of the skin disease were due to poor socio-economical conditions.

Aesthetic problems associated with the cosmetic use of bleaching products.

BACKGROUND AND AIM: The use of skin bleaching products for cosmetic purposes is a frequent practice (25-96%) in women from sub-Saharan Africa. The dermatologic complications associated with this practice have been comprehensively reported. The aim of this work was to study the epidemiologic, clinical, and cosmetic aspects of these complications in order to produce better therapeutic guidelines for their management. METHODS: This was a prospective, descriptive study performed over a 6-month period. All women aged between 15 and 50 years, who consulted a dermatologist (Le Dantec Hospital or Institute of Social Hygiene), experienced a complication associated with artificial depigmentation, and agreed to take part in the study, were included. The data were input and analyzed using Epi info version 6.0. RESULTS: Eighty-six female patients were included, with a mean age of 29.34 years (range, 16-49 years). The breakdown by level of education was as follows: primary (48.8%), secondary (18.3%), and higher (8.5%) education. Twenty-two per cent of our population had not attended school. The mean monthly cost of skin bleaching products was 6.22 euros. The initial skin tone before using skin bleaching products was black in 41.5% of patients, light in 32.9%, and intermediate in 25.6%. The mean duration of exposure was 6.7 +/- 5 years (range, 1-30 years). The breakdown by skin bleaching products showed that topical corticosteroids were the most frequently used (78%), followed by hydroquinone (56%), products based on vegetable extracts (31.7%), caustic products (8.5%), and, finally, products of unknown composition (41.4%). Two components or more were frequently combined (86.5%). The aesthetic complications of artificial depigmentation were the reason for consulting a dermatologist in 10 patients (12%). Nineteen types of aesthetic complication were reported in our sample. Hyperpigmentation of the joints was the most frequently found complication (85.4%), followed by striae atrophicae (72%) and skin atrophy (59.8%). The number of aesthetic complications found in the patients varied from one to nine. Patients frequently presented (71.9%) with other complications associated with artificial depigmentation. CONCLUSIONS: Aesthetic complications associated with artificial depigmentation are common, but rarely the reason for consulting a dermatologist. In the absence of suitable therapeutic agents, prevention, based on informing women of the damaging effects of artificial depigmentation, is the only way forward.

Epidemiologic, clinical, and therapeutic features of acne in Dakar, Senegal.

BACKGROUND: Acne, a chronic inflammatory dermatosis of the pilosebaceous follicle, is very widespread worldwide, affecting 75-80% of adolescents, with an impact on their quality of life. The etiologic factors are not always the same, and the treatments proposed are not always well tolerated in black individuals. AIMS: To determine how acne affects the black population in Dakar, Senegal, and to assess the results of and tolerance to treatment. METHODS: This was a prospective study conducted on a sample of patients who attended consultations for acne in our dermatology department between December 2002 and March 2003, and who agreed to take part in the study (informed consent was obtained). An anonymous questionnaire was used as a support. RESULTS: Ninety-three patients were included in the study, with a hospital frequency of 5.3% and an average age of onset of acne of 25.58 years. In 75% of cases, the acne sufferers were young women, 76.3% of whom were single. Acne was of the superficial inflammatory type in 76.3%, retentional in 67.7%, and nodulocystic in 12.9% (Some patients who have acne vulgaris may have pustules, papules and nodules or cystic lesions so the percentages add up to 100). Signs of hyperandrogeny were observed in 19.1%, with hirsutism in 93.8%. Artificial depigmentation was noted in 38.7%. Stress was found in 89.2% and a depressive state in 3.4%. Solar exposure aggravated the lesions in 52.7%. In terms of therapy, only 1.1% received oral retinoids. An improvement was noted in 67.2%, and resistance was observed in 7.3%. DISCUSSION: In Dakar, Senegal, patients with acne consult later than elsewhere. The majority of cases are women, contrary to certain other studies. The inflammatory forms predominate in adult women. The most frequent location is on the face. An evolution to pigmentary disorders is found in 67.7%. Predisposing factors include the use of depigmenting cosmetic products and sun exposure. Local treatment, such as benzoyl peroxide and topical retinoids, which promote melanoderma in black skin, is widely used. The exorbitant cost of oral retinoids considerably limits their use in Senegal. CONCLUSION: Acne, an adolescent pathology, is increasingly being observed in adults using depigmenting cosmetics. The multiple clinical forms are dominated by inflammatory acne. The many relapses and cost of treatment have a detrimental effect on the quality of life of patients.

[Occupational allergic contact dermatitis in Dakar]. / Les eczemas de contact professionnels a Dakar.

Occupational dermatitis, mainly allergic contact dermatitis and skin irritations are increasing because of new allergens and diversity of the industrial procedures. In Senegal occupational contact dermatitis are currently observed and they are not declared at our social security institution. The aim of our trial was to determinate the frequency of occupational allergic contact dermatitis, the allergens responsible and the exposed occupations. We included in a one year lasting prospective trial, all patients with occupational contact dermatitis confirmed by positive cutaneous allergological tests. Among 201 cases of contact dermatitis, 27 (12,91%) were included and predominant occupational sectors were building, mechanics, health, cleaning and trade. Main responsible allergens were dichromate of potassium (7), N-isopropyl N-phenylparaphenylenediamine (3), fragrance mix (3), thiuram mix (3), colophane (3), formaldehyde (2), nickel sulphate (2), Chalk (2). Building sector was the most frequent source because of high use of dichromate of potassium in cement and formaldehyde in painting-glue. In mechanics, N-isopropyl N-phenylparaphenylenediamine is present in rubbers and fragrance mix in oils. Occupational dermatitis in health workers are due to presence of thiuram mix in the gloves, and dichromate of potassium found in antiseptics. To decrease the incidence of occupational contact dermatitis in our country, we have to promote prevention among workers by using individual protective outfits and increasing workers medical survey and information about risks and means of prevention.

EPR and DFT studies of the structure of phosphinyl radicals complexed by a pentacarbonyl transition metal.

Paramagnetic complexes M(CO)5P(C6H5)2, with M = Cr, Mo, W, have been trapped in irradiated crystals of M(CO)5P(C6H5)3 (M = Cr, Mo, W) and M(CO)5PH(C6H5)2 (M = Cr, W) and studied by EPR. The radiolytic scission of a P-C or a P-H bond, responsible for the formation of M(CO)5P(C6H5)2, is consistent with both the number of EPR sites and the crystal structures. The g and 31P hyperfine tensors measured for M(CO)5P(C6H5)2 present some of the characteristics expected for the diphenylphosphinyl radical. However, compared to Ph2P*, the 31P isotropic coupling is larger, the dipolar coupling is smaller, and for Mo and W compounds, the g-anisotropy is more pronounced. These properties are well predicted by DFT calculations. In the optimized structures of M(CO)5P(C6H5)2 (M = Cr, Mo, W), the unpaired electron is mainly confined in a phosphorus p-orbital, which conjugates with the metal d(xz) orbital. The trapped species can be described as a transition metal-coordinated phosphinyl radical.