Hydration monitoring in the prevention of recurrent idiopathic urinary tract infections in pre-menopausal women.

Objective: To assess whether the use of simple hydration monitoring can encourage adequate hydration and reduce urinary osmolality and the incidence of urinary tract infections (UTIs) in a population of susceptible pre-menopausal women with recurrent idiopathic urinary infections.

Subjects And Methods: The study included 28 pre-menopausal women who had at least two idiopathic UTIs in the previous 6 months. Urinary osmolality was assessed by the patients at each void by a simple hand-held probe, and the readings over 4 months compared. Monthly urine culture was compared between successive 4-month periods in which the probe was or was not used.

Results: The study was completed by 17 women. There was a significant shift towards urine of lower osmolality over the 4-month period using the probe (Pearson's chi 2 < 0.001). Significantly fewer urinary tract infections developed during the 4 months using the probe (McNemar's chi 2 = 0.046).

Conclusions: The use of the osmolality probe encouraged the subject to maintain adequate hydration. The resulting augmentation of the natural urethral 'washout' mechanism led to lower osmolality urine and a reduction in the incidence of UTIs.