First case report of topical tacalcitol for vitiligo repigmentation

Vitamin D and the skin: what should a dermatologist know?

Although first discovered in 1931, vitamin D has seen an increased interest in the scientific community over the past decades, including the dermatology field. Vitamin D promotes calcium and phosphorus absorption; however, the actions of vitamin D are not confined to bone. Indeed, there is now overwhelming and compelling scientific data that vitamin D plays a crucial role in a plethora of cellular function and in extra-skeletal health. Except for fatty fish livers, very few foods naturally contain vitamin D; and the major source of vitamin D comes from skin exposure to sunlight via ultraviolet B. Keratinocytes are unique in the body as not only do they provide the primary source of vitamin D for the body, but they also possess both the enzymatic machinery to metabolize the vitamin D produced to active metabolites. This has been referred to as the photoendocrine vitamin D system. Vitamin D regulates keratinocytes proliferation and differentiation; and plays a role in the defense against opportunistic infections. Multiple factors are linked to vitamin D status; and a growing number of dermatologic diseases has been linked to vitamin D status such as atopic dermatitis, psoriasis, vitiligo, and cutaneous cancers. In this article, we reviewed the potential determinants of vitamin D status, as its implications in dermatologic diseases.

25-hydroxyvitamin D status in patients with alopecia areata

Introduction

Alopecia areata (AA) is a T cell-mediated autoimmune disease that causes inflammation around anagen-phase hair follicles. Insufficient levels of vitamin D have been implicated in a variety of autoimmune diseases.

Aim

To investigate the status of serum 25-hydroxyvitamin D (25(OH)D) in patients with AA, serum 25(OH)D concentrations were compared between AA patients and healthy controls and thus determine if a possible association exists between serum 25(OH)D levels and AA.

Material and methods

The study comprising 41 patients diagnosed with AA and 32 healthy controls was conducted between October 2010 and March 2011. The serum vitamin D levels of the study group were determined by high performance liquid chromatography. Serum levels of calcium, phosphorus, alkaline phosphatase, and parathyroid hormone were also evaluated.

Results

The study was based on 41 patients aged between 20 and 50 (mean: 32.8 ±7.5). The control group included 32 healthy persons aged between 20 and 51 (mean: 32.7 ±7.5). Serum 25(OH)D levels in patients with AA ranged from 5.0 to 38.6 ng/ml with a mean of 8.1 ng/ml. Serum 25(OH)D levels in healthy controls ranged from 3.6 to 38.5 ng/ml with a mean of 9.8 ng/ml. There was no statistically significant difference in the serum vitamin D level between AA patients and healthy controls (p > 0.05).

Conclusions

Deficient serum 25(OH)D levels are present in patients with AA. However, considering the high prevalence of vitamin D deficiency in Turkey, no difference was noted between AA patients and controls.

Association of ApaI and BsmI polymorphisms with vitiligo risk: a meta-analysis

BACKGROUND

It has been reported that polymorphisms of the vitamin D receptor gene (VDR) such as ApaI or BsmI may affect the risk of vitiligo. However, the results have been inconsistent.

AIM

To evaluate the association between two common polymorphisms (ApaI and BsmI) in the VDR gene and the susceptibility to vitiligo.

METHODS

The PubMed, Cochrane Library and China National Knowledge Infrastructure (CNKI) databases were searched, and OR with 95% CI was calculated. The strength of association and vitiligo risk was assessed under five genetic models: allele, dominant, recessive, homozygous and heterozygous.

RESULTS

Six relevant studies were identified, including five studies that assessed the ApaI polymorphism and four the BsmI polymorphism (some overlapped). The meta-analysis results indicated that either the ApaI or the BsmI gene polymorphism may increase the risk of vitiligo in East Asian populations (aa + Aa vs. AA: OR = 1.40, 95% CI 1.01-1.96, P < 0.05; bb vs. Bb + BB: OR = 1.32, 95% CI 1.09-1.59, P < 0.01). No publication bias was detected in this meta-analysis.

CONCLUSION

The current meta-analysis suggests that the ApaI a allele or BsmI bb genotype are associated with the risk of vitiligo in East Asian populations. Thus, these polymorphisms could be potential biomarkers for early detection of vitiligo.

Off-label uses of topical vitamin D in dermatology: a systematic review

BACKGROUND

Topical vitamin D is approved by the US Food and Drug Administration for the treatment of psoriasis but is also used off-label in the treatment of a variety of cutaneous diseases despite a lack of evidence-based guidelines.

OBJECTIVE

The objective of this study was to provide evidence-based clinical guidelines for the off-label use of topical vitamin D in the treatment of dermatologic disease.

METHODS

A systematic literature review was conducted via the MEDLINE, Embase, and CENTRAL databases for off-label uses of topical vitamin D analogues in the treatment of dermatologic disease other than psoriasis. The data were synthesized, and evidence-based recommendations were rendered according to the highest level of evidence available.

RESULTS

A total of 165 articles met the inclusion criteria. A moderate to strong recommendation was given for the use of topical vitamin D in combination with corticosteroids and phototherapy in vitiligo and as monotherapy for various ichthyoses, morphea, pityriasis alba, prurigo nodularis, and polymorphous light eruption. There is evidence showing that topical vitamin D is ineffective in the treatment of actinic keratosis, seborrheic keratosis, lichen planus, seborrheic dermatitis, alopecia areata, chemotherapy-induced alopecia, and hypertrophic scars.

CONCLUSION

Topical vitamin D analogues have an important role in the off-label treatment of dermatologic disease, but higher quality studies are still required.

The association of vitamin D receptor gene polymorphisms and serum 25-hydroxyvitamin D levels with generalized vitiligo

BACKGROUND

Vitiligo is an acquired depigmentation autoimmune disorder that has been described as being associated with lower levels of 25-hydroxyvitamin D [25(OH)D]. Genetic variations within the vitamin D receptor (VDR) gene could lead to significant receptor dysfunction, and could further affect the formation of the biologically active 25(OH)D. Therefore, we hypothesized that VDR polymorphisms might be involved in vitiligo by affecting the formation of 25(OH)D.

OBJECTIVES

To evaluate the potential association between VDR polymorphisms and vitiligo susceptibility and the serum levels of 25(OH)D.

METHODS

We performed a hospital-based study of 749 patients with vitiligo and 763 matched controls. We investigated four VDR polymorphisms (FokI, BsmI, ApaI and TaqI) to determine whether they are associated with vitiligo susceptibility in the Chinese population. In addition, the levels of 25(OH)D were measured to evaluate possible associations between the VDR polymorphic variants and clinical and laboratory findings of vitiligo.

RESULTS

A significantly decreased risk of developing vitiligo was found to be associated with the BsmI-B, ApaI-A and TaqI-t alleles. According to the genotype distribution, 25(OH)D concentrations were significantly higher in patients carrying the FokI ff or ApaI AA genotypes compared with those carrying the FF or aa genotypes. Logistic regression analysis also showed a dose-response relationship between decreased risk of vitiligo and increased 25(OH)D levels in ApaI-A variant genotype carriers.

CONCLUSIONS

Our findings suggest that these VDR polymorphisms are associated with 25(OH)D levels and that there exists a genetic predisposition for vitiligo in the Chinese population.

Narrowband ultraviolet B phototherapy in childhood vitiligo: evaluation of results in 28 patients

Phototherapy using narrowband ultraviolet B (UVB) is considered among the treatments of choice in vitiligo, even in childhood. The objective of the current study was to evaluate the profile of safety and effectiveness of such therapy in a group of children. An open, uncontrolled study was performed on 28 children with vitiligo who were receiving narrow band UVB phototherapy. The children were classified according to vitiligo type and phototype. Family history and presence of thyroid disease were investigated. Eighteen patients had received other treatments that was stopped 3 months before starting phototherapy. Phototherapy was administered twice a week. The mean duration of therapy was 10 ± 3.4 months. The mean total dose administered was 156.12 ± 79.4 J/cm(2). Photographs of lesions were taken before and at the end of treatment. The response to phototherapy was expressed as percentage of repigmentation. The data were statistically analyzed using SPSS (SPSS Inc., Chicago, IL). Fourteen percent of patients showed excellent response, 28.6% good response, 25% moderate response, and 28.6% mild response; the remaining 3.5% were not responsive. No side effects were observed except mild erythema requiring a decrease in dosage in a few patients. The results of the present study confirm those of other authors, with better results than adults probably related to good adherence of patients and their families. Nevertheless, high cumulative doses are not necessarily related to a good response. Therefore, we suggest stopping treatment after 6 months in nonresponding cases.

A pilot study assessing the role of 25 hydroxy vitamin D levels in patients with vitiligo vulgaris

BACKGROUND

Very low vitamin D levels have been noted in patients with a variety of autoimmune diseases.

OBJECTIVE

To determine whether low vitamin D levels are associated with autoimmunity in the setting of vitiligo vulgaris.

METHODS

A prospective cohort study was conducted on 45 consecutive patients with vitiligo vulgaris. 25-Hydroxyvitamin D levels were determined from sera collected at the time of study enrollment. Logistic regression analysis of the relationship of 25-hydroxyvitamin D levels to disease state was performed, including surface area, recent-onset vitiligo, Fitzpatrick skin type and ethnicity, dairy intake, and both personal and family history of autoimmunity. Multiple univariate and multivariate logistic regression models were developed to assess the interrelationship of these parameters.

RESULTS

25-Hydroxyvitamin D levels were divided into 3 groups: 31.1% were normal (>30 ng/mL), 55.6% were insufficient (<30 ng/mL), and 13.3% were very low (<15 ng/mL). Insufficient 25-hydroxyvitamin D levels were associated with increasing Fitzpatrick phototypes (odds ratio [OR] = 1.76, 95% confidence interval [CI] = 1.12-2.77). Very low 25-hydroxyvitamin D levels were associated with comorbid autoimmune illness (OR = 10.00, 95% CI = 1.06-94.7), but not with age, gender, race/ethnicity, family history of vitiligo or autoimmune disease, new-onset disease, or body surface area affected. None of the surveyed patients reported daily vitamin D intake of greater than 200 IU.

LIMITATIONS

This study consists of a small cohort that assesses point prevalence without assessing seasonal variation in vitamin D levels.

CONCLUSIONS

Very low 25-hydroxyvitamin D levels (<15 ng/mL) appear to be a reasonable screening tool for the presence of comorbid autoimmunity. Furthermore, we demonstrate that Fitzpatrick phototype, rather than ethnicity, is specifically associated with 25-hydroxyvitamin D levels that are insufficient (<30 ng/mL).

Vitiligo in children

BACKGROUND

Vitiligo is an acquired depigmentary disorder affecting around 1% of the world's population. In 25% of cases it has its onset prior to the age of 14 years.

DATA SOURCES

Articles on vitiligo in children published after 1995 were retrieved from PubMed. The prevalence, etiology, clinical presentation, differential diagnosis, treatment and management of vitiligo in children were summarized.

RESULTS

Vitiligo is characterized by acquired, sharply demarcated depigmented macules or patches on the skin, the mucous membranes and/or white hair and it is mainly differentiated from congenital achromic skin lesions. It is frequently associated with various autoimmune diseases. Hashimoto's thyroiditis is the most common association in children. Information on the nature, possible causes and course of the disease leads to acceptance of the disorder and higher compliance with the treatment. The choice of medical treatment depends on the type, location and duration of lesions as well as the eagerness of the child and his/her parents to pursue therapy.

CONCLUSION

The management of childhood vitiligo includes information and reassurance of young patients and their parents on the disease, thyroid investigation, avoidance of trigger factors, topical treatment and proper follow-up.