Serum Zinc Concentrations in Patients with Pulmonary Tuberculosis

Bangladesh is a tuberculosis (TB) burden country. It is one of the most important causes of mortality and morbidity and a major barrier of social and economic development. Zinc is a major trace element and an essential component of the body immune system. It's an important determinant of resistance to infection by maintaining cell mediated immunity. This analytical case control study was conducted in the Department of Internal Medicine, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh to see the association of serum zinc concentrations with pulmonary tuberculosis (PTB) in adult population (18-60 years) from January 2015 to January 2016. Freshly diagnosed PTB patients before initiating anti-TB chemotherapy as cases (N=43) and TB negative subjects as controls (N=48) were included conveniently in this study with a rigid selection criteria. Serum zinc concentrations were estimated by using atomic absorption spectrophotometer. The mean±SD age and BMI of the case group and control group were 33.30±14.71 and 32.69±11.60 years, 19.88±2.31 and 22.08±2.80 kg/m2 respectively. The concentrations of serum zinc were significantly lower (P=0.01) in PTB group (840.9±230.0 μgm/l) compared with the control group (965.6±219.9 μgm/l). There was marked variation of mean±SD serum zinc concentrations between male (1008.95±246.16 μgm/l) and female (937.24±200.35 μgm/l) in control group (P=0.182) though the variation is minimal in PTB group (P=0.724). The serum zinc concentrations showed positive correlation with BMI (P=0.642) but negative correlation with age (P=0.023) in both case and control. The lower serum zinc concentrations (12.06%) in PTB patients indicate relative immune deficiency. Routine assessment of serum zinc concentration of PTB patients should be considered and further outcome should be assessed with zinc supplementation.