Pityriasis lichenoides (PL) is a cutaneous disease of unknown origin, with an autoinvolutive course, that can occur in pediatric patients. Traditionally, acute and chronic variants have been described, but other special forms of presentation have been reported. We reviewed the clinical records and histopathologic specimens of all pediatric patients diagnosed with PL in our hospital from 1980 to 1995 to assess the clinicopathologic features of this disorder in our environment. Twenty-two of the 118 cases reviewed were pediatric patients less than 15 years old (12 males and 10 females, 18.6% of all patients). Their ages ranged from 3 to 15 years, with a mean of 9.3 years. Most of the patients (72%) had the chronic variant of the disease, while the remainder had an acute course. One patient suffered from acute ulceronecrotic PL. Systemic treatments prescribed were erythromycin in eight patients, PUVA in five patients, and methotrexate in one patient. Three patients had a prolonged course with more than two episodes. Acute and chronic PL are polar extremes, but individual cases cannot be classified only on the basis of histopathologic data, since coexistence of lesions in different stages of evolution can lead to sampling bias. Acute ulceronecrotic forms and the presence of a variable degree of cellular atypia in the infiltrate are liable to cause differential diagnostic problems with lymphomatoid papulosis (LP), which cannot be completely resolved on the basis of T-cell receptor clonal rearrangement detection.

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We characterized inflammatory and atherogenic profiles of Spanish patients with psoriasis compared with matched controls. After NB-UVB therapy we demonstrated improvement in psoriasis and some systemic inflammation markers, which were not mediated by enhancement of vitamin D synthesis.

Psoriasis has been related to metabolic syndrome (MS). Adipocytokines produced by white adipose tissue may be involved in the pathogenesis of psoriasis and its association with MS. Our objectives were to characterize the profile of a number of different inflammatory and atherogenic markers, vitamins, adipokines and cytokines and their potential involvement in MS in patients with moderate-to-severe psoriasis without joint involvement compared to anthropometrically matched controls, and to evaluate correlation with severity of the skin disease and changes after narrow-band UVB (NB-UVB) phototherapy. We designed a prospective cross-sectional study. Baseline waist circumference, body fat composition, lipid, carbohydrate and calcium metabolism profile, inflammation markers, homocysteine and vitamins D, B6, B12 and folic acid, leptin, resistin, omentin, lipocalin-2, adipocyte fatty acid-binding protein, retinol-binding protein-4 (RBP-4), interleukin-6, soluble tumour necrosis factor receptor 1 (sTNFR1) and interleukin-17 of 50 psoriasis patients and 50 gender, age and body mass index-matched controls were recorded, then evaluated after NB-UVB in the patients. The patients had higher baseline serum concentrations of leptin, RBP-4, lipocalin-2 and sTNFR1. Baseline psoriasis area and severity index correlated with serum concentrations of RBP-4 and lipocalin-2 only. Principal components analysis disclosed a component including vitamins B12, B6, folic acid, calcidiol and HDL-cholesterol that was only present in healthy controls and opposed to a cluster of variables which promote MS. This component was absent in the patients. Our results point to lipocalin-2 and RBP-4 as relevant mediators of the trend towards MS in psoriatic patients.