Asymptomatic hyperleukocyturia in hemodialysis patients analyzed by the automated urinary flow cytometer

The number of urinary white blood cells (WBC) is useful marker of urinary tract infection in patients without renal insufficiency. On the other hand, it is unclear what urinalysis data are normal in hemodialysis (HD) patients. The occurrence and numbers of WBC in 75 asymptomatic HD patients and 133 healthy individuals as controls were determined by the automated urinary flow cytometer (UF-100, Sysmex Co., Kobe, Japan). The finding of hyperleukocyturia (>10 WBC per high power field of 400x microscopic magnification) was observed in 46.7% of HD patients. Urinary WBC significantly increased with decrease in the urinary volume. It may not be appropriate to indiscriminately apply the diagnostic criteria of pyuria for patients with normal renal function to dialysis patients because the number of urinary WBC was closely related to the urinary volume in HD patients.