Elevated urinary norepinephrine in interstitial cystitis

Objectives. To measure urinary catecholamines and determine the extent to w hich they may be elevated in urine from patients with interstitial cystitis (IC). Methods. Random urine samples from patients with IC (n = 111) and urine fro m normal volunteers (n = 92) were acidified on collection (voided and cathe terized specimens) and assayed for catecholamine (norepinephrine or normeta nephrine) by enzyme-linked immunosorbent assay. Creatinine levels in these urine samples were also measured. Results. Analysis of the data indicated that patients with IC had a higher urinary level of the neurotransmitter norepinephrine compared with the meas ured levels in the urine of normal volunteers (89.1 +/- 58.3 versus 54.9 +/ - 37.1 mu g/g creatinine, P <0.05). The metabolite normetanephrine was simi lar in the urine samples from these two groups. Urine from patients with bl adder outlet obstruction (n = 11) did not have elevated amounts of urinary norepinephrine. The norepinephrine levels were not statistically different in the urine samples from patients with symptomatic and asymptomatic IC. Th e elevated urinary levels in patients with IC did not decrease after treatm ent with sodium pentosanpolysulfate (Elmiron), heparinoids, dimethyl sulfox ide, or combinations of these during 1 to 15 months of treatment. Conclusions. Norepinephrine was found to be elevated in the urine from pati ents with IC compared with urine from normal controls. This would be consis tent with increased sympathetic (adrenergic) activity from the bladders of patients with IC or possibly from increased adrenal activity, since stress is associated with symptom increase in some patients with IC. Norepinephrin e levels did not decrease with treatment nor did they differ between sympto matic and asymptomatic patients at the time of urine collection. UROLOGY 53 : 1140-1143, 1999. (C) 1999, Elsevier Science Inc. Ail rights reserved.