Abstract: Background: Most of the organism’s vitamin D (VD) is obtained through the cutaneous synthesis after exposure to the sun’s UVB radiation. Sunscreens are indicated for the prevention of actinic damage to the skin, however, there are few clinical trials assessing the synthesis of cutaneous VD in real-life situations of sun exposure with ordinary clothing and usual photoprotection. Objectives: To evaluate the synthesis of VD with suberythemal sun exposure in healthy adults using topical photoprotection (SPF 30). Methods: Quasi-experimental study, conducted at Rio de Janeiro (Brazil), during winter, with 95 healthy adults who had 25-OH-VD checked twice, 24 hours apart, and were exposed to the sun (UVB=20 mJ/cm2), according to a randomized grouping: SC - use of SPF 30 on the face, neck and chest (n=64), NO - no sunscreens (n=10), CO - confined from sun exposure for 24h (n=21). The groups were matched according to the propensity score related to gender, age, phototype, body mass index, glycosylated hemoglobin and baseline levels of VD. The outcome evaluated was the variation (ΔVD) in serum level of 25-OH-VD (ng/ml) between the groups. Results: A statistically significant difference was identified between CO and SC groups [median (p25-p75)]: ΔVD =1.4 (-0.3-3.6) vs. 5.5 (4.8-6.6); p<0.01. There was no difference between SC and NO groups: 5.4 (3.1-6.1) vs. 4.1 (2.5-6.0); p=0.17. Study limitations: Laboratory analysis technique (chemiluminescence) with great variability, loss of food intake standardatization, unbalanced groups. Conclusions: Suberythemal sun exposure with sunscreen (SPF 30) provides similar vitamin D serum variation than without photoprotection in healthy adults.

Abstract Lithium has been implicated in the exacerbation of pre-existing psoriasis, in the induction of psoriasis on previously uninvolved skin of psoriasis patients, and in the triggering of psoriasis for the first time in patients without a personal or family history. Lithium-induced psoriasis (and its resistance to treatment) is one of the major reasons for noncompliance in patients treated with lithium. We describe a male patient who developed generalized ostraceous psoriasis whose clinical appearance mimicked dermatitis neglecta, 10 months after starting therapy with lithium.

Tumor triquilemal proliferante é uma neoplasia incomum que surge do istmo folicular, cuja característica histológica é a presença de ceratinização triquilemal. Apresenta-se usualmente como nódulo solitário no couro cabeludo de mulheres idosas. Descreve-se um caso de tumor triquilemal proliferante que se apresenta como lesão tumoral nodular na região glútea de uma jovem de 16 anos de idade

Proliferating trichilemmal tumor (PTT) is an uncommon neoplasm arising from the follicular isthmus. Its histological characteristic is the presence of trichilemmal keratinization. PTT usually presents as a solitary nodule on the scalp of elderly women. We describe a case of a PTT on the gluteal region (buttocks) of a 16-year-old female, presenting as a solitary nodule