Urinary interleukin-2 inhibition in patients with cystitis

An inhibitor of interleukin-2 activity (IL-2-IN) is present in the urine of most patients during the acute phase of untreated bacterial cystitis (UTI). We measured urinary IL-2-IN activity in 30 adults with uncomplicated UTIs and followed the patients for an additional 6 months. Urinary IL-2-IN activity ranged between 0 and 1.97 units/mg urine creatinine (U/mg u.c.). Relatively low levels of IL-2-IN (less than 0.5 U/mg u.c.) correlated with a prior history of recurrent UTIs (p less than 0.01), and also were predictive of a subsequent UTI during the 6 month follow-up, regardless of the prior medical history (p less than 0.01). Measurement of urinary IL-2-IN during the untreated phase of a UTI may prove helpful for directing antibiotic prophylaxis against subsequent UTIs.