Vitamin D levels are significantly lower in patients with recurrent inflammatory spinal cord disease, according to a study published online Monday in Archives of Neurology. Vitamin D is a steroid vitamin that promotes the intestinal absorption and metabolism of calcium and phosphorus. In recent years, low levels of vitamin D have been linked to a variety of autoimmune conditions, including multiple sclerosis (MS). However, the importance of vitamin D in monophasic or recurrent non-MS spinal cord diseases including transverse myelitis and neuromyelitis optica is unknown, according to background information in the article. Transverse myelitis (TM) is a disease of the spinal cord in which there is involvement of the myelin sheath that protects nerve fibers; symptoms include back pain and weakness in the legs. Neuromyelitis optica (NMO) is a disease of the central nervous system that affects the optic nerves and spinal cord. Maureen Mealy, of Johns Hopkins University and colleagues investigated the association between low serum vitamin D levels and recurrent spinal cord disease. They analyzed data on vitamin D levels among 77 patients with monophasic (having only one phase or stage) and recurrent inflammatory diseases of the spinal cord, adjusting for season, age, sex, and race. The study found that vitamin D levels were significantly lower in patients who developed recurrent spinal cord disease. \"Our findings suggest that there may be an association between lower total 25-hydroxyvitamin D levels in patients with recurrent TM/NMO/ spectrum disorders as compared with their counterparts with monophasic disease,\" the authors report. They suggest that future studies are needed to further assess the relationship between vitamin D and recurrent spinal cord disease.