Relationship between Use of Hydroxyurea and Cholelithiasis in Patients with Major and Intermediate β-thalassemia

Background and Cholelithiasis is a common problem among patients with homozygous major and intermediate β-thalassemia due to chronic hemolysis, ineffective erythropoesis and other factors that causes variety of side effects. Hydroxyurea (HU) decreases hemolysis by increasing HbF production in homozygous β-thalassemia patients. Up to now, there have not been evidences about relationship between use of Hydroxyurea and cholelithiasis in the patients. The aim of this study was to determine the relationship between use of HU and incidence of cholelithiasis in patients with major and intermediate β-thalassemia referred to thalassemia research center of Mazandaran University of medical sciences at Boo-Ali Sina hospital of Sari, IRAN. This historical cohort study was performed in 2006. Study population was major and intermediate β-thalassemia patients referred to Boo-Ali Sina Hospital of Sari, IRAN. The patients were divided to two groups: case and control groups. The case group (36 patients) was consisted of major or intermediate β-thalassemia patients using hydroxyurea at least for one year, and the control group were: non-hydroxyurea user patients or beginning to use the drug less than 3 months. The groups were matched on order to age, gender and severity of the disease. Severity of the disease was determined according to grading, clinical and laboratory characteristics of the patients. Data about demographic information, severity of the disease and results of hepatobiliary ultrasound were recorded in a questionnaire. The data was analyzed using SPSS (11) software and t-test, Chi-square test and fisher exact test. Thirty-six [20 women (55.6%)] patients in case group and 36 [19 women (52.8%)] patients in control group were studied. The mean duration of use of hydroxyurea was 67.9 ± 25.5 months with maximum 108 months (9 year). The mean dosage of the drug was 14.9 ± 5.9 mg/kg with maximum dosage 34 mg/kg. Thirteen (48.1%) patients in control group (12 cholelithiasis, 1 sludge) and 6 (19.4%) patients in case group (5 cholelithiasis, 1 sludge) had abnormal hepatobiliary sonography. The difference between two groups was significant statistically (P<0.02). Among the different variables, a significant relationship was detected between gender of the patients and effect of HU on cholelithiasis. This study showed that the incidence of cholelithiasis in major and intermediate β-thalassemia patients using hydroxyurea was less than non-hydroxyurea user patients did. As a result, it seems that there was a preventive effect of hydroxyurea in incidence of cholelithiasis in major and intermediate β-thalassemia patients.