Photoletter to the editor: Atypical primary cutaneous mucormycosis of the scalp.

Mucormycosis of the scalp is a rare cutaneous presentation of the disease. It is also an unusual infection in children. We present the case of a 4-year-old girl with acute lymphoblastic leukemia, who presented with atypical cutaneous mucormycosis simulating an ecthyma gangrenosum lesion. Risk factors for the infection are diabetes, neoplastic diseases, immunosuppression in organ transplant recipients, and neutropenia. The cutaneos forms have been associated with trauma, burns and surgical wounds. First line treatment is amphotericin B. Posaconazole was recently approved to treat invasive mucormycosis. Surgical removal of the infected tissue is indicated.

A Double-Blind, Randomized Clinical Trial of Niacinamide 4% versus Hydroquinone 4% in the Treatment of Melasma.

Background. Multiple modalities have been used in the treatment of melasma with variable success. Niacinamide has anti-inflammatory properties and is able to decrease the transfer of melanosomes. Objective. To evaluate the therapeutic effect of topical niacinamide versus hydroquinone (HQ) in melasma patients. Patients and Methods. Twenty-seven melasma patients were randomized to receive for eight weeks 4% niacinamide cream on one side of the face, and 4% HQ cream on the other. Sunscreen was applied along the observation period. They were assessed by noninvasive techniques for the evaluation of skin color, as well as subjective scales and histological sections initially and after the treatment with niacinamide. Results. All patients showed pigment improvement with both treatments. Colorimetric measures did not show statistical differences between both sides. However, good to excellent improvement was observed with niacinamide in 44% of patients, compared to 55% with HQ. Niacinamide reduced importantly the mast cell infiltrate and showed improvement of solar elastosis in melasma skin. Side effects were present in 18% with niacinamide versus 29% with HQ. Conclusion. Niacinamide induces a decrease in pigmentation, inflammatory infiltrate, and solar elastosis. Niacinamide is a safe and effective therapeutic agent for this condition.

[Assessment of moisturizing creams available in México]. / Evaluación de cremas humectantes disponibles en México.

UNLABELLED: There is a broad diversity of moisturizers for the treatment of dry skin; however, we do not know their real effectiveness. The objective here was to evaluate different products through their capacity to increase the epidermal hydration level (EHL) and to reduce the transepidermal water loss (TEWL). MATERIALS AND METHODS: We evaluated twenty moisturizers in sixteen individuals. The analysis was made on volar forearm and basal measurements were made for EHL and TWEL with the later application of 8 gm of each moisturizer on a 2 cm2 area. RESULTS: For the EHL we found significant differences among the products (p < 0.0001), but only 35% (n = 7) of the moisturizers registered ascending levels of hydration in the course of measurements. The variance analysis for TEWL also was significant (p < 0.0001). CONCLUSIONS: In the short term only a few products induced a significant change in EHL. This study demonstrates the necessity to obtain objective information in order to avoid false publicity claims that may erroneously influence our prescription habits.

Histochemical and immunohistochemical study in melasma: evidence of damage in the basal membrane.

The pathogenesis of melasma has not been clearly elucidated. Using Fontana Masson; diastase-resistant periodic acid-Schiff stains; and immunohistochemistry to stem cell factor (SCF), its receptor c-kit, anti-mast cell tryptase, and anti-collagen type IV antibody, we evaluated melasma lesions and compared them with perilesional skin and photoprotected skin. Samples were taken from lesional and photoprotected nonlesional skin in 24 patients. In other 24 patients, we took biopsies of lesional and perilesional skin. With Fontana Masson, we observed many pigmented basal cells protruding into the dermis of the melasma skin. Periodic acid-Schiff stain and anti-collagen type IV showed damage on the basal membrane in 95.5% and 83%, respectively, in melasma lesion. The immunoreactivity of SCF and the prevalence of mast cells were increased in the dermis of melasma compared with perilesional dermis. The expression of c-kit was significantly increased at lesional epidermis; a frequent protrusion of c-kit-positive basal cells into the dermis was evident in 70% versus that in 29% of perilesional skin. The expression of c-kit was increased at lesional dermis of melasma compared with perilesional skin. We found a low correlation between c-kit expression and prevalence of mast cells; these were increased in melasma skin. The results may suggest a role of SCF, c-kit, and mast cells in the pathogenesis of melasma. We were surprised by the unexpected evidence of damage to basal membrane (BM), which could facilitate the fall or the migration of active melanocytes and melanin into the dermis allowing the constant hyperpigmentation in melasma.