Clinical Significances of Carbamylated Hemoglobin in Patients with Chronic Renal Failure

Koh, Kwan Pyo; Lee, Tae Won; Jeong, In Kyung; Hong, Seung Pyo; Lim, Chun Gyoo; Kim, Myung Jae

Abstract

Carbamylated hemoglobin (CarHb) is formed by the reaction of hemoglobin with cyanate derived from the spontaneous dissociation of in vivo urea. Previous studies have shown that formation of CarHb depends upon both the severity and the duration of renal failure. To study the clinical significances of CarHb in Korean patients with chronic renal failure, we measured CarHb levels by high-performance liquid chromatography in 159 CRF patients and 46 normal controls. Patients with CRF had a higher CarHb concentration than normal controls (107.9+/-58.8 vs 35.1+/-14.2 microgramVH/gHb; P<0.001). In patients with CRF, nondialysis group had a higher value than dialysis group (129.8+/-77.9 vs 98.7+/-46.1 microgramVH/gHb; P<0.05). There were no siginificant difference in CarHb levels between hemodialysis (92.0+/-35.8microgramVH/gHb) and peritoneal dialysis (106.7+/-55.3microgramVH/gHb) groups. CarHb levels were not different between diabetic and nondiabetic patients in predialysis and hemodialysis groups. Although there was a significant difference in peritoneal dialysis group, the BUN levels were also lower in diabetic patients than nondiabetic patients. There were no correlation between CarHb and HbA1c percentage in patients with diabetes. CarHb levels were positively correlated with BUN (r=0.489; P<0.001) and creatinine (r=0.458; P<0.01) concentrations. There were negative correlations between CarHb and both Kt/V (r=-0.358; P<0.05) and URR (r=-0.415; P<0.05) in hemodialysis patients. In conclusion, CarHb may be a useful index of uremic control in patients with chronic renal failure, and are independent of the mode of dialysis and the presence of diabetes.