Impact of Hydroxyurea on Liver, Kidney, and Hematological Parameters in Sickle Cell Anemia Patients Above 15 Years Old in Sana'a City.

Background: Sickle cell anaemia (SCA) is a hereditary haemoglobin disorder associated with high morbidity. Hydroxyurea (HU) has become a key disease-modifying therapy for SCA. Objective: To evaluate the effects of HU on liver and kidney functions, along with haematological parameters, in SCA patients aged 15 years and above in Sana'a city. Methods: A cross-sectional study was conducted on 72 patients with SCA who received HU. Participants filled out questionnaires regarding risk factors and complications, and data were collected through interviews and laboratory tests. Statistical analysis was performed using SPSS. Results: The study included 72 SCA patients (55.6% males). Most participants showed stable liver enzymes, but mild elevations in AST (36.1%) and ALT (33.3%) were observed, likely related to SCA-induced hemolysis rather than HU toxicity. Elevated bilirubin levels (direct, indirect, and total) were common (81.9%, 86.1%, and 76.4%, respectively), reflecting the hemolytic nature of SCA. Regarding renal function, 51.4% of patients had low creatinine levels, which may reflect glomerular hyperfiltration and tubular dysfunction typical in SCA rather than HU toxicity. No significant adverse effects on renal function were attributed to HU. Conclusion: Hydroxyurea was well tolerated and showed no evidence of inducing major hematological, hepatic, or renal toxicity. Slight effects on renal function, including lower creatinine levels, were observed and may reflect underlying disease physiology rather than drug-related changes. However, as this was a cross-sectional study, causal relationships could not be established, and longitudinal studies are recommended to assess long-term hepatic and renal outcomes.