Ocular side effects of desferal in patients with beta thalassemia

ABSTRACT

To evaluate the ocular side effects of desferal in beta-thalassemia major patients. This cross-sectional study was conducted on 100 beta-thalassemia major subjects. All patients underwent complete ophthalmic examination, color vision test, and visual field evaluation. Electroretinography [ERG] was performed for 50 patients. Mean patient age was 14.4 years. Only 9 patients complained from ocular problems including nyctalopia [8 subjects] and permanent visual loss [one case], but eye examination revealed abnormalities in 74 subjects including cataract in 43, fundus abnormality in 9; abnormal visual field in 71 with the most common abnormality being paracentral scotoma [64%], and abnormal color vision in 35 with the most common abnormality being tritanopia [81%]. All patients had abnormal ERG with abnormal amplitude of "a" and "b" waves in scotopic phase. There was no significant correlation between age, duration of desferal usage or serum ferritin with ocular findings. All patients who received more than 40 mg/kg/day of desferal had ocular abnormalities. The main risk factor for ocular finding in desferal users is the dosage- ERG and perimetry are useful for early detection of ocular problems in these patients