Serum levels of homocysteine, folate and vitamin B12 in patients with vitiligo before and after treatment with narrow band ultraviolet B phototherapy and in a group of controls.

The association between vitamin B12, folate, homocysteine and vitiligo were studied in several studies, but the results are contradictory. Narrow-band ultraviolet B (NBUVB) phototherapy is now considered as a gold standard for the treatment of diffuse vitiligo. The effects of NBUVB phototherapy on both vitamin B12, folate and homocysteine levels have not been studied in vitiligo patients yet. Serum levels of vitamin B12, folate and homocysteine were measured in vitiligo patients and control group and also both before and after NBUVB phototherapy in vitiligo patients. While levels of homocysteine in patients with vitiligo were significantly higher than controls (16.9±8.4 vs. 10. 9±3.4 μmol/L; p<0,001) vitamin B12 and folate levels were not different (p>0.05). NBUVB phototherapy led to a 33.7±21.9% (0-75%) response in patients with vitiligo after 80 seccions. Treatment with NBUVB improved vitiligo and decreased serum levels of vitamin B12 (375±151 vs. 346±119 pg/ml, p=0.024), while serum levels of folate and homocysteine did not change significantly after treatment (p=0.914, p=0.127). Further studies are needed to clarify the influence of NBUVB phototherapy on folate, vitamin B12 and homocysteine levels in patients with vitiligo. Furthermore, studies with the analysis of skin levels of homocysteine rather than circulating levels may be useful to elucidate the effects of phototherapy on homocysteine levels.