Association of Vitamin D Status with the Immune Response in Active Pulmonary Tuberculosis Patients with Chronic Pulmonary Aspergillosis

Objective The aim of the study was to determine the associations between vitamin D (VD) and cytokine levels in active pulmonary tuberculosis (PTB) patients with chronic pulmonary aspergillosis (CPA). Methods One hundred seventy-two active PTB patients, twenty-eight PTB patients with CPA (PTB-CPA), and sixty healthy subjects were included in the study. The concentrations of serum 25-hydroxyvitamin D, interleukin (IL)-1β, IL-4, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF-α) were measured by ELISA. Results A significantly lower VD level was detected in PTB-CPA patients (14.96±10.89 ng/mL) than in both PTB patients (20.72±8.07 ng/mL, p<0.01) and controls (23.90±8.16 ng/mL, p<0.001). VD deficiency was significantly more prevalent in PTB-CPA patients than in PTB patients (OR=2.86, 95% CI: 1.22-6.69; p=0.01) or controls (OR=5.33, 95% CI: 2.02-14.11; p=0.0005). In the PTB group, VD levels exhibited a significant inverse correlation with only IL-6 (r=-0.376, p=0.0001), whereas in PTB-CPA patients, stronger inverse correlations were observed with IL-6 (r =-0.691, p=0.0005) and IL-8 (r=-0.538, p=0.01). In cavitary PTB patients, a significant inverse link was found between VD and IL-1β and IL-6 levels (all p≤0.05). Conclusion Our data revealed a high prevalence of VD deficiency in all groups, predominantly in PTB-CPA patients. The inverse correlations between VD levels and IL-6 and IL-8 levels in PTB-CPA patients as well as between VD and IL-1β and IL-6 levels in cavitary PTB patients, provide further evidence for the role of VD as a regulator of inflammatory pathways in the context of coinfection.