['Previous studies have demonstrated that endogenous bone morphogenic protein-7 (BMP-7) level is reduced in acute kidney injury and administration of exogenous BMP-7 has a beneficial effect on kidney function. In spite of preventive management, contrast-induced nephropathy (CIN) is still the third cause of acute deterioration of kidney function in hospitalized patients. With this background in mind, we studied changes in serum BMP-7 in a group of patients with chronic kidney disease and contrast-induced nephropathy.', 'We enrolled 45 consecutive adult patients with a baseline serum creatinine ≥ 1.4 mg/dl admitted for coronary angiography. We measured serum BMP-7 levels before and 48 h after coronary angiography. The primary end point was the development of CIN, defined as an increase in serum creatinine concentration by 0.25 mg/dl or 25% over the baseline value within 72 h from contrast exposure.', 'Overall, CIN occurred in 8 (17%) patients. The concentrations of serum BMP-7 were significantly decreased in the CIN group compared to baseline (488.6 ± 56.8 vs. 356.4 ± 24.8, P = 0.01); in contrast, the concentration of BMP-7 level did not change in patients without CIN (444.6 ± 54.6 vs. 440.0 ± 53.9, P = 0.09).'] Does bone morphogenic protein-7 serum level decrease significantly in patients with contrast-induced nephropathy?