Prerenal success in chronic kidney disease

Renin-angiotensin system inhibitors and diuretics are commonly prescribed to patients with chronic kidney disease to reduce systemic blood pressure. The renin-angiotensin inhibitors also reduce intraglomerular pressure. The lower pressures may result in initial increases in the serum creatinine. The long-term renoprotection provided by these therapies establishes the basis for tolerating the initial increases. However, physicians are sometimes reluctant to continue these treatments when the serum creatinine increases. Several reasons for this reluctance are discussed, including the failure to distinguish between hemodynamic- and parenchymal-mediated changes in kidney function. In addition, the lack of a formal term and place in our diagnostic algorithm for increases in serum creatinine that derive from ultimately beneficial hemodynamic alterations may be a hindrance. The term "prerenal success" is proposed to describe hemodynamic alterations associated with improved prognosis and is placed in a new algorithm. Finally, recent literature describing harmful effects of increases in serum creatinine in other cohorts is reviewed; these cohorts are sufficiently different from the stable chronic kidney disease patient that the results ought not to be extrapolated.