Clinical features and risk factors of renal dysfunctions in thalassemic patients.

Introduction: Chronic anemia, iron overload, and iron chelation therapy are the main contributing factors for renal complications in thalassemia, e.g., nephrolithiasis, glomerular disease, and renal tubular dysfunction. The prevalence and associated factors for developing renal dysfunctions in Thai patients with thalassemia, however, remained limited. This study aimed to determine the prevalence and risk factors of renal dysfunctions in patients with thalassemia.

Methods: A cross-sectional study was conducted on adult patients with thalassemia disease at Srinagarind Hospital, Khon Kaen University, Thailand. All patients were evaluated for complete blood count, blood chemistry, urinalysis, and urine biochemistry. Renal tubular dysfunction was defined as existing in at least one of the following parameters including; proteinuria, hypercalciuria, hypouricemia with uricosuria, or hypophosphatemia with phosphaturia. Logistic regression analysis was used to identify associated factors for renal dysfunctions.

Results: Of 105 patients, renal tubular dysfunction was found in 60 patients (57.1%). In multivariate analysis of the clinical risk factors for renal tubular dysfunction in thalassemia patients, age per 10 year increase (adjusted odds ratio [AOR] = 1.4, 95% CI: 1.0-2.0, p value 0.01) and Hb E/beta-thalassemia (AOR = 3.6, 95% CI: 1.3-10.3, p value 0.01) were statistically proven to be associated with renal tubular dysfunction. Hyperuricosuria was a significantly associated factor for microhematuria. (AOR = 2.9, 95% CI: 1.1-8.0, p value 0.03).

Conclusions: Renal dysfunctions are prevalent in thalassemia patients, with older age and Hb E/beta-thalassemia genotype as significant risk factors for renal tubular dysfunction. Hyperuricosuria is a risk factor for microhematuria. Renal dysfunctions should be recognized and monitored in aging patients with Hb E/beta-thalassemia.