Neutrophilia may be observed in patients with acute pyelonephritis or acute prostatitis. Nonregenerative anemia can be present if infection is chronic or if decreased renal function has developed as a consequence of pyelonephritis. The method of urine collection influences results of the urinalysis. Midstream voided urine evaluates all of urogenital tract but may contain bacteria from the urethra. Catheterization evaluates the bladder, ureters, and kidneys but may result in iatrogenic trauma or iatrogenic infection.
Manual expression can result in iatrogenic hematuria.
Cystocentesis evaluates the bladder and kidneys and there is little chance of contamination of sample. Prostatic fluid may reflux into the bladder so evidence of prostatic disease may be detected in cystocentesis samples. Isosthenuria suggests renal impairment due to pyelonephritis or a polyuric disorder may be present and predisposing to infection. White blood cells in the urine is pyuria. Bacteria in the urine may be pathogens or contaminants from the urethra.