ABNORMAL DARK-ADAPTATION IN SICKLE-CELL-ANEMIA

  • 1 January 1981
    • journal article
    • research article
    • Vol. 98  (2) , 189-194
Abstract
Patients with sickle cell anemia may be Zn-deficient. Zn deficiency causes delayed dark adaptation. Dark adaptation was studied in 13 patients with homozygous sickle cell anemia. Six patients had delayed dark adaptation. Their mean plasma and neutrophil Zn levels were 93.83 .+-. 8.26 .mu.g/100 .mu.l and 37.33 .+-. 11.88 .mu.g/1010 cells, respectively, compared to the corresponding mean values for 7 patients with normal dark adaptation of 105.86 .+-. 13.31 and 86.71 .+-. 19.53. For the 6 patients with delayed dark adaptation, the lower neutrophil Zn value, but not the plasma value, was significant (P < 0.01). Three of the 6 were treated with oral Zn, with improvement in their dark adaptation. Neutrophil Zn levels correlated inversely (r = -0.77, P < 0.01) with log relative threshold at 30 min. Patients with sickle cell anemia may show decreased ability to dark-adapt that is related to Zn deficiency.