PHOENIX, ARIZ. — Small increases in serum creatinine that are not currently viewed as signaling renal dysfunction are highly predictive of mortality in patients with severe sepsis, William Macias, M.D., reported at a meeting sponsored by the Society of Critical Care Medicine.
In a review of data on 1,226 patients, 28-day mortality reached 42.9% in patients whose creatinine rose by 0.2-0.49 mg/dL from baseline during the first 24 hours, said Dr. Macias of Lilly Research Laboratories in Indianapolis.
When an increase in creatinine met or exceeded the current marker of 0.5 mg/dL on day 1, 57.7% of patients died within 28 days. Mortality was 25.7% for patients with early increases of less than 0.2 mg/dL.
“The current definition may be too insensitive to detect acute kidney injury in patients with severe sepsis,” Dr. Macias said. Relative serum creatinine increases that are greater than 25%—as well as acute increases of 0.5 mg/dL or greater—are associated with significant increases in mortality.
The researchers drew the patient population from placebo groups in the Integrated Database of Severe Sepsis and Xigris Therapy, a repository of data from trials for Lilly's drotrecogin alfa activated. The investigators were interested in patients with moderate increases of 0.2-0.49 mg/dL in serum creatinine because these are not currently associated with kidney injury.
“If you have increases from 0.2 to less than 0.5 [mg/dL], you have mortality of 40%” regardless of baseline level, Dr. Macias said. “If you have increases greater than 0.5 [mg/dL], you have mortality greater than 50%—no matter where they started.”
Deaths typically occurred within 5 days if creatinine levels rose on day 1. Patients with high baseline creatinine that did not rise tended to die after day 15. “It was the same pattern over and over again. If you have an increase in creatinine you pay a very, very early penalty,” he said.