When are laboratory tests indicated in patients with vitiligo?

BACKGROUND: Vitiligo has been associated with multiple endocrine and immune conditions. Several laboratory tests have been assessed in this disease with controversial results. OBJECTIVE: The aim of this study is to analyze the levels autoantibodies, basal glycaemia, vitamin B12, folic acid and thyroid function and its association with the diagnosis and outcome of vitiligo patients through a case-control study. MATERIAL AND METHODS: This case-control study was performed on 196 consecutive patients with vitiligo referred to our Dermatology Department. As a control group, 160 healthy individuals without vitiligo or known history of immunologic/endocrine disease were included. Data were analyzed using the SPSS 17.0 statistical software package. RESULTS: Clinical, analytical and demographic data have been recorded. Our results showed that anti-thyroid peroxidase antibody and anti-parietal gastric cell antibody could be useful laboratory markers in a subpopulation of vitiligo patients. However, testing anti-nuclear antibody, anti-thyroglobulin antibody, folic acid and vitamin B12 seems to have limited clinical implication and diagnostic relevance in our routine clinical practice. LIMITATIONS: This study addressed a selected population of vitiligo patients in Spain and may not generalize to different clinical settings or regions. The study of a wider sample would confirm these findings and allow a detailed analysis of the above factors as a function of the clinical subtype of vitiligo. CONCLUSION: We have determined the more efficient serological markers to order in vitiligo patients. Our findings suggest that anti-thyroid peroxidase antibody and anti-parietal gastric cell could be useful tests for the characterization of specific subpopulations of vitiligo patients in terms of severity and co-morbidity, so their determination could have a prognostic value.

Pathogenesis-based therapy reverses cutaneous abnormalities in an inherited disorder of distal cholesterol metabolism.

Identification of the underlying genetic, cellular, and biochemical basis of lipid metabolic disorders provides an opportunity to deploy corrective, mechanism-targeted, topical therapy. We assessed this therapeutic approach in two patients with Congenital Hemidysplasia with Ichthyosiform erythroderma and Limb Defects (CHILD) syndrome, an X-linked dominant disorder of distal cholesterol metabolism. On the basis of the putative pathogenic role of both pathway-product deficiency of cholesterol and accumulation of toxic metabolic intermediates, we assessed the efficacy of combined therapy with lovastatin and cholesterol. We also evaluated the basis for the poorly understood, unique lateralization of the cutaneous and bone malformations of CHILD syndrome by analyzing gene activation in abnormal and unaffected skin. Ultrastructural analysis of affected skin showed evidence of both cholesterol depletion and toxic metabolic accumulation. Topical treatment with lovastatin/cholesterol (but not cholesterol alone) virtually cleared skin lesions by 3 months, accompanied by histological and ultrastructural normalization of epidermal structure and lipid secretion. The unusual lateralization of abnormalities in CHILD syndrome reflects selective clearance of keratinocytes and fibroblasts that express the mutant allele from the unaffected side. These findings validate pathogenesis-based therapy that provides the deficient end product and prevents accumulation of toxic metabolites, an approach of potential utility for other syndromic lipid metabolic disorders.