RESUMEN
Objective:To investigate serum levels of 25-hydroxyvitamin D [25-(OH)D3], the vitamin D receptor(VDR), LL-37, cytokines such as interleukin 6(IL-6)and tumor necrosis factor-α(TNF-α)in elderly and non-elderly patients with pulmonary tuberculosis, and to study the correlation between serum vitamin D levels and clinical characteristics.Methods:A total of 56 elderly patients and 56 non-elderly patients with active pulmonary tuberculosis admitted to Chengdu Public Health Clinical Center from January 2019 to March 2019 were enrolled.The levels of 25-(OH)D3, VDR, LL-37, IL-6 and TNF-α were detected by ELISA and compared between the two groups.Clinical data such as the number of T lymphocytes, lesions and cavities in bilateral lung fields and extra-pulmonary tuberculosis were collected.Results:There were significant differences in serum vitamin D levels [(28.94±12.88)nmol/L vs.(34.47±12.78)nmol/L, t=3.650, P=0.025], while levels of VDR, LL-37, IL-6 and TNF-α(all P>0.05)were similar between the elderly and non-elderly groups.Besides, patients in the elderly group were associated with significantly lower levels of CD4 + T lymphocytes [(295.71±153.83)×10 6/L vs.(421.25±206.00)×10 6/L]and CD8 + T lymphocyte count [159.5(101.0, 239.0)×10 6/L vs.261.5(187.0, 409.0)×10 6/L]than those in the nonelderly group(all P=0.000). Also, there were more severe pulmonary tuberculosis cases in the elderly group than the non-elderly group [(51/56, 91.1%) vs.(28/56, 50.0%), χ2=22.730, P=0.000]. The serum level of 25-(OH)D3 was positively correlated with CD4 + T cell count in elderly patients( r=0.190, P< 0.05). Conclusions:Elderly patients with pulmonary tuberculosis have a high proportion of severe tuberculosis and reduced serum levels of vitamin D, CD4 + T cell count and CD8 + T cell count, compared with non-elderly patients.Attention should be paid to vitamin D levels and their potential impact on disease progression in elderly patients with active tuberculosis.