INTERLEUKIN-1-ALPHA AND INTERLEUKIN-1 RECEPTOR ANTAGONIST IN THE URINE OF CHILDREN WITH ACUTE PYELONEPHRITIS AND RELATION TO RENAL SCARRING

Urinary concentrations of interleukin-1 alpha (IL-1 alpha) and interle ukin-l receptor antagonist (IL-1ra) standardized to urinary creatinine concentrations were studied. The median standardized IL-1 alpha creat inine quotient in children with first-time acute pyelonephritis was 3. 6 pg/mu mol, but was nondetectable in children with recurrent pyelonep hritis, children with non-renal febrile conditions and children conval escent after acute pyelonephritis (p < 0.05-0.01). IL-1ra levels were also significantly higher in children with acute first-time pyelonephr itis (median of 239 pg/mu mol) compared to these three groups of child ren (p < 0.01-0.001). The highest urinary IL-1ra levels, however, were found in the healthy controls (median value 1.019;p < 0.001). Both cy tokines were higher among children younger than one year compared to o lder children. The acute IL-1 alpha creatinine quotients were lowest i n children with uptake defects on (TC)-T-99m-dimercaptosuccinic acid ( DMSA) scintigraphy both during the acute infection (reflecting the acu te inflammation) (p < 0.001) and 1 year after the acute infection (ref lecting permanent kidney scarring) (p < 0.01). In conclusion, persisti ng high urinary levels of IL-1 alpha were associated with less renal i nflammation and scarring.