Urinary pH measures urine acidity or alkalinity (normal range 4.5-8.0), reflecting kidney acid-base regulation and dietary influences. Very acidic urine promotes uric acid kidney stones; persistently alkaline urine may indicate Proteus UTI or renal tubular acidosis type I.
FAQs
Can diet significantly change urine pH?
Yes. High meat intake produces acidic urine; plant-based diets produce alkaline urine. Dietary modification targeting urine pH is effective for uric acid stone prevention.
What is renal tubular acidosis type I?
A distal tubule defect preventing urine acidification below pH 5.5, causing metabolic acidosis, calcium phosphate stones, and hypokalaemia. Treated with alkali replacement.
Why does Proteus infection alkalinise urine?
Proteus produces urease, converting urea to ammonia, dramatically raising urine pH and promoting struvite crystal formation.
How is urine pH measured?
By dipstick colorimetry as part of routine urinalysis. Values vary considerably throughout the day.
