TFRC and Schnyder corneal dystrophy: Based on microcytosis, hypochromia, and high sTfR/log serum ferritin index, the prevalence of iron deficiency of 7% obtained in this study is much lower than what was obtained by other authors who reported deficiency in 20% and 17.1% of SCD patients using the combination of microcytosis and hypochromia alone [22].