Pyuria is most commonly associated with urinary tract infection in patients with urinary symptoms. Persistent sterile pyuria, however, may be an indication of underlying renal disease.
- Urine dipstick testing is an important screening tool in general practice.
- Dipstick findings of urinary leucocytes or nitrite are suggestive of urinary tract infection (UTI).
- If pyuria on dipstick is persistent but UTI is not confirmed by repeated midstream urine culture, further investigation is warranted, including testing for proteinuria and haematuria, assessing renal function and performing a renal ultrasound.
- Persistent sterile pyuria also warrants further simple investigation.
- Patients require referral to a nephrologist if they have any significant, persistent abnormality such as proteinuria, haematuria, sterile pyuria or impaired renal function detected.