We compared the predictive performances of NO levels at day 6, at day 21 and MPO activity at one month in assessing MDRD-pGFR (predicted glomerular filtration rate by the Modification of diet in renal disease) equation at six months, to the predictive performances of all MDRD-eGFR variables at all times potentially predictive, by applying multivariable stepwise linear regression. The gene discussed is MPO; the disease is kidney disorder.