Myeloperoxidase in chronic kidney disease.

Numerous lines of evidence implicate a role of myeloperoxidase (MPO) in the pathogenesis of cardiovascular disease (CVD). It is a well accepted fact that patients with chronic kidney disease (CKD) are at an increased risk for CVD. MPO is a pro-oxidant enzyme which could be involved in the increased susceptibility of these patients to CVD. Hence, the levels of plasma MPO was determined in healthy controls as well as in patients with CKD [stratified with the level of their kidney failure as CKD stages II-V (end stage renal disease)]. Plasma MPO was assayed by a spectrophotometric method. Serum urea and creatinine were estimated on a clinical chemistry analyzer using standard laboratory procedures. The mean plasma MPO levels were significantly lower with advancing stages of renal failure (P < 0.001). There was a positive correlation between MPO and GFR (r = +0.89, P < 0.001) and a negative correlation with urea (r = -0.85, P < 0.001) and creatinine (r = -0.82, P < 0.001). While an inverse association was observed between plasma MPO and urea in CKD patients, such an association was not observed in control subjects (P = 0.43). In conclusion, the decline in plasma MPO levels may be due to the inhibitory effect of uraemic toxins on the enzyme.