Tuberculosis remains a public health issue worldwide. Identifying its risk factors, such as vitamin D deficiency, is mandatory so as to target the preventive strategies. We aimed to study the association between vitamin D deficiency and extrapulmonary tuberculosis. We conducted a case-control study including all cases of extrapulmonary tuberculosis hospitalized in the infectious diseases department over a two-year period from April 2017 until April 2019. We included 45 cases of extrapulmonary tuberculosis and 45 controls matched by gender and age. Vitamin D deficiency was significantly more frequent among cases (80% vs 37.7%; p < 0.001), with an odds ratio (OR) of 6.5 (IC95% = 2.5-16). The mean levels of vitamin D were significantly lower among cases (11.9 ± 8.8 vs 22.3 ± 11 ng/mL; p < 0.001). In the multivariate analysis, we found that vitamin D deficiency was an independent predictor of extrapulmonary tuberculosis (OR = 6.13; p < 0.001). The cutoff value of vitamin D predictor of extrapulmonary tuberculosis was 18.5 ng/mL which was associated with a sensitivity of 80% and a specificity of 62%. Our study provides strong evidence that vitamin D deficiency was an independent predictor of extrapulmonary tuberculosis. More studies are needed in order to evaluate the potential preventive role of vitamin D and the benefit of possible supplementation.

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维生素 D 缺乏与肺外结核的关系：病例对照研究

结核病仍然是世界范围内的公共卫生问题。必须确定其风险因素，例如维生素 D 缺乏症，以便制定预防策略。我们旨在研究维生素 D 缺乏与肺外结核病之间的关联。我们进行了一项病例对照研究，其中包括 2017 年 4 月至 2019 年 4 月两年内在传染病科住院的所有肺外结核病例。我们纳入了 45 例肺外结核病例和 45 例性别和年龄匹配的对照。维生素 D 缺乏在病例中明显更常见（80% 对 37.7%；p < 0.001），优势比 (OR) 为 6.5 (IC95% = 2.5-16)。维生素 D 的平均水平在病例中显着降低（11.9 ± 8.8 对 22.3 ± 11 ng/mL；p < 0.001）。在多元分析中，我们发现维生素 D 缺乏是肺外结核的独立预测因素（OR = 6.13；p < 0.001）。肺外结核的维生素 D 预测因子的临界值为 18.5 ng/mL，其敏感性为 80%，特异性为 62%。我们的研究提供了强有力的证据，证明维生素 D 缺乏是肺外结核病的独立预测因素。需要更多的研究来评估维生素 D 的潜在预防作用和可能补充的益处。我们的研究提供了强有力的证据，证明维生素 D 缺乏是肺外结核病的独立预测因素。需要更多的研究来评估维生素 D 的潜在预防作用和可能补充的益处。我们的研究提供了强有力的证据，证明维生素 D 缺乏是肺外结核病的独立预测因素。需要更多的研究来评估维生素 D 的潜在预防作用和可能补充的益处。