Pyuria



The finding of more than four white blood cells per high-power field on a urine specimen is suggestive of urinary tract inflammation, although as with hematuria, the precise site is not identi­fied. Pyuria as an isolated finding is most com­monly associated with bacterial urinary tract in­fection. When associated with hematuria or proteinuria, pyuria is suggestive of parenchymal renal disease such as glomerulonephritis or in­terstitial nephritis.

The presence of pyuria should initiate a search for urinary tract infection, particularly when the patient complains of dysuria, flank pain, or fever. Renal imaging studies are often indicated to ex­clude the presence of renal parenchymal scarring, obstruction, or abscess formation, particularly when accompanied by signs of renal dysfunction such as azotemia.