Figure 1. Approaches to diagnosis and treatment of patients with elevated levels of serum creatinine, at 3 stages of disease: newly discovered elevation of creatinine level (A), progressive chronic renal failure (B) and just before end-stage renal disease (C). The creatinine values and time course are hypothetical and are intended for illustrative purposes only. The thresholds for referral are lower for children than for adults. CBC = complete blood count, BP = blood pressure, ACE = angiotensin-converting enzyme, rhGH = recombinant human growth hormone, ESRD = end-stage renal disease.