Serum Uric Acid and Creatinine Levels in Patients Receiving Anti-tuberculosis Therapy: A Cross-Sectional Study at a Tertiary-Care Hospital in Lahore, Pakistan

Background: Anti-tuberculosis treatment is effective, but some drugs can cause biochemical abnormalities.Hyperuricemia is a recognized effect of pyrazinamide-containing therapy.Local information on serum uric acid and creatinine during routine anti-tuberculosis treatment is limited.Objective: This study aimed to determine serum uric acid and creatinine levels and the frequency of hyperuricemia and elevated creatinine in patients receiving first-line anti-tuberculosis therapy and to assess associations between recorded treatment duration and these biochemical parameters, including an exploratory comparison between participants treated for ≤3 months and >3 months.Methods: This cross-sectional laboratory-based study included 96 patients receiving first-line antituberculosis therapy at Mayo Hospital, Lahore, from November 2025 to February 2026.Serum uric acid and creatinine were measured by the uricase-peroxidase and Jaffe kinetic alkaline picrate methods, respectively, on a Siemens Atellica automated chemistry analyzer.Continuous variables were summarized as mean ± standard deviation and median (interquartile range).As continuous variables departed from normality, Spearman rank correlation was used to assess associations between treatment duration and biochemical parameters.The Mann-Whitney U test was used for the exploratory comparison between duration groups, and Fisher's exact test was used for hyperuricemia.Results: Mean age was 30.15 ± 12.75 years, and mean treatment duration was 4.38 ± 2.92 months.Fifty-four participants (56.3%) had pulmonary tuberculosis, and 42 (43.8%)had extrapulmonary tuberculosis.Median uric acid was 5.00 mg/dL (IQR 3.90-6.63;mean 5.62 ± 2.51), and median creatinine was 0.72 mg/dL (IQR 0.62-0.80;mean 0.71 ± 0.18).Hyperuricemia occurred in 19 (19.8%; 95% CI 13.1-28.9%)participants and elevated creatinine in 2 (2.1%; 95% CI 0.6-7.3%).Treatment duration showed a weak inverse correlation with uric acid (Spearman ρ = -0.213,p = 0.037), but not with creatinine (ρ = 0.066, p = 0.522).Uric acid was higher in the ≤3-month group than in the >3-month group (6.52 ± 3.14 vs. 4.82 ± 1.39 mg/dL; p = 0.005).Hyperuricemia was also more frequent in the ≤3-month group (35.6% vs. 5.9%; p < 0.001).Male participants had higher uric acid than female participants (6.46 ± 2.86 vs. 4.96 ± 1.99 mg/dL; p = 0.002).Neither parameter differed significantly by case status or tuberculosis site.Conclusion: Hyperuricemia occurred in approximately one-fifth of participants receiving first-line antituberculosis therapy, whereas elevated creatinine was uncommon.Although hyperuricemia was more frequent in the ≤3-month group, treatment regimen and pyrazinamide exposure were not independently verified against drug charts, and pretreatment biochemical values were unavailable.Therefore, the duration-defined difference cannot establish a treatment-related effect or specifically attribute hyperuricemia to pyrazinamide exposure.Prospective studies with serial measurements and verified drug exposure are needed.