From the Research
The appropriate management for a patient with sterile pyuria involves identifying and treating the underlying cause, with a focus on ruling out sexually transmitted infections (STIs) and other non-bacterial causes, as suggested by the study published in 2018 1. The diagnosis of sterile pyuria should be confirmed with a complete urinalysis and urine culture showing white blood cells without bacterial growth. Common causes of sterile pyuria include:
- Partially treated urinary tract infections
- Kidney stones
- Interstitial cystitis
- Genitourinary tuberculosis
- Certain medications
- Sexually transmitted infections, such as Chlamydia trachomatis, as reported in the study from 1996 2 For suspected partially treated UTIs, empiric antibiotics like nitrofurantoin 100mg twice daily for 5-7 days or trimethoprim-sulfamethoxazole 160/800mg twice daily for 3 days may be appropriate, as supported by the study from 1995 3. However, it is essential to note that the presence of pyuria or positive nitrite does not necessarily indicate a bacterial infection, and antibiotics should not be prescribed solely based on these findings, as highlighted in the study from 2018 1. If tuberculosis is suspected, refer for specialized testing and treatment. For interstitial cystitis, consider phenazopyridine 200mg three times daily for symptom relief and potentially pentosan polysulfate sodium 100mg three times daily as a long-term treatment. Discontinue any medications that might be causing the condition, such as NSAIDs or certain antibiotics. Additional workup may include imaging studies like renal ultrasound or CT scan to identify structural abnormalities, and referral to urology for cystoscopy if symptoms persist despite initial management. The goal is to identify the specific etiology rather than simply treating the presence of white blood cells in urine, as sterile pyuria is a finding that requires investigation of its underlying cause, as emphasized in the studies from 2014 4 and 2000 5.