Serum vitamin D levels in patients with vernal keratoconjunctivitis and its relationship with disease severity

Purpose To evaluate the serum vitamin D levels of patients with vernal keratoconjunctivitis (VKC) Method A total of 39 VKC patients (21 males and 18 females) and 32 healthy individuals (19 males and 13 females) were enrolled in this study with the mean age of 18.38 ± 8.83 and 21.6 ± 9.43, respectively. The type and the grade of VKC were identified for each patient and serum 25-hydroxyvitamin D (25(OH)D) levels of all subjects were evaluated. Results The patients affected by VKC had statistically significant lower 25(OH)D levels (27.64 ± 8.50 ng/mL) than healthy subjects group (35.96 ± 11.34 ng/mL) (p = 0.001). A reverse correlation was found between the serum vitamin D levels and the severity of the VKC but it was not statistically significant (r = −0.159, p = 0.33). Besides, there were a few cases with severe and very severe VKC (2 in grade 3 and 4 in grade 4). Patients with the mixed type of the disease had lower serum vitamin D levels in comparison to tarsal and limbal forms but the difference was not statistically significant (p = 0.38). Conclusion This study shows that the patients affected by VKC have lower vitamin D levels in comparison to healthy subjects and the screening of all patients with VKC for vitamin D levels seems rational.