INTRODUCTION
Zona zoster is a painful disease with dermatomal localized vesicles. It is a disease that can cause significant acute morbidity and long-term sequelae, including chronic pain, which can seriously impair the quality of life even in those receiving appropriate antiviral therapy. Zona zoster occurs following a decrease in cell-mediated immunity specific to varicella zoster virus (VZV), and therefore the risk of zona zoster among individuals with impaired cell-mediated immune function is increased [1,2]. The most important risk factor for zona zoster is advanced age. Aging reduces the skin’s ability to synthesize vitamin D, and increased skin pigmentation reduces the effectiveness of UVB to stimulate vitamin D synthesis [3,4].
Cell mediated immunity is known to decrease with age, and decreased cell mediated immunity is associated with reactivation of VZV [5]. Vitamin D is important for calcium homeostasis, bone health, and prevention of fractures. Vitamin D has effects on metabolic, neoplastic, inflammatory, and immune events [6,7]. Vitamin D deficiency is considered to be a serum 25-hydroxyvitamin D (25-OH-D) level of less than 20 ng / ml. 25-OH-D vitamin values between 20 and 30 ng / ml are considered insufficient and are considered clinically important. The prevalence of vitamin D deficiency varies according to geographic regions with different levels of sunlight exposure [7,8]. It has been found that vitamin D deficiency is frequently seen in various viral infectious diseases. Vitamin D affects the secretion of antimicrobial peptides associated with several toll-like receptors (TLRs) that have antiviral effects. Similarly, 1,25- (OH) 2-D strongly stimulated the release of human cathelicidins from neutrophils and possibly monocytes and natural killer cells. Human cathelicidin is induced by TLR1 / 2 activation and contributes to mucosal immunity and provides antiviral effects [7,8]. There are few publications on the relationship between vitamin D levels and zona zoster. Chao et al. suggested that vitamin D may affect both human susceptibility to varicella zoster virus and the clinical course of zona zoster [8].
In this study, we aimed to compare the vitamin D level in zona zoster patients with that of healthy controls and to investigate the possible role of vitamin D level in the development of zona zoster.