Background: A link between vitamin D deficiency and susceptibility to bacterial and viral infections has recently been suggested.
Aim: To investigate a possible association between vitamin D deficiency and urinary tract infection (UTI).
Methods: A case-control study was undertaken comprising 75 children aged 2-7 years with UTI (cases) compared with 75 healthy controls in terms of serum 25 hydroxyvitamin D [25(OH)D] levels. Serum 25(OH)D levels were measured using a chemiluminescence assay. For cases, dimercaptosuccinic acid (DMSA) renal scan was used as the gold standard to distinguish between acute lower UTI (cystitis) and acute pyelonephritis.
Results: Median (IQR) 25(OH)D levels were lower in the UTI group [14.5 ng/mL (9.4-18.8)] than in the controls [27 ng/mL (22.4-39.0)] (p< 0.001). In addition, the prevalence of 25(OH)D levels <20 ng/mL was higher in the children with UTI than in the controls (68% vs 18%) (p< 0.001). There was a statistically significant difference between the cystitis and pyelonephritis groups in mean (SD) serum 25(OH)D levels-18.76 (9.35) ng/mL vs 13.94 (6.97) ng/mL, p< 0.05, respectively.
Conclusion: Low serum vitamin D is associated with UTI and supports the hypothesis that children with low vitamin D levels could be at greater risk of UTI.
Keywords: 25-hydroxyvitamin D; cystitis; pyelonephritis; urinary tract infection.