The cysteinyl leukotriene D4 receptor antagonist montelukast for the treatment of interstitial cystitis

PURPOSE: The presence of leukotriene D4 receptors in human detrusor myocytes and increased urinary leukotriene E4 in patients with interstitial cystitis and detrusor mastocytosis imply a role for cysteinyl containing leukotrienes as proinflammatory mediators in this disease. We examined the efficacy of the cysteinyl leukotriene 1 receptor antagonist montelukast for treating patients with interstitial cystitis and detrusor mastocytosis. MATERIALS AND METHODS: Ten women in whom interstitial cystitis was diagnosed according to National Institute of Diabetes and Digestive and Kidney Diseases criteria and who also had detrusor mastocytosis with a minimum of 28 mast cells per mm.2 muscle tissue were included in this study. Patients received a single dose of montelukast daily for 3 months. The efficacy of treatment was determined by 24-hour urinary frequency, nocturia and pain using visual analog scales. RESULTS: After 1 month of montelukast treatment there was a statistically significant decrease in 24-hour urinary frequency, nocturia and pain which persisted during the 3 months of treatment. After 3 months 24-hour urinary frequency had decreased from 17.4 to 12 voidings (p = 0.009), nocturia had decreased from 4.5 to 2.8 (p = 0.019) and pain had decreased from 46.8 to 19.6 mm. on a visual analog scale (p = 0.006). No side effects were observed during treatment. CONCLUSIONS: Montelukast treatment resulted in significant improvement in urinary frequency and pain. Its efficacy for decreasing urinary frequency and pain imply a role of leukotriene receptor antagonists for managing interstitial cystitis but further placebo controlled clinical studies are needed.     

Mast cell involvement in interstitial cystitis

A prospective study was designed to examine the relationship of mast cells, and eosinophilic leukocyte density and mediator levels to clinical and histological parameters of interstitial cystitis. Interstitial cystitis and control patients underwent bladder biopsy with histological examination, and quantification of intact and degranulated mast cell and eosinophilic leukocyte density. In addition, bladder tissue histamine content, urinary prostaglandin E2 excretion rates, and serum and urinary major basic protein levels were determined. A strong relationship among detrusor mast cell density, especially degranulated, and degree of epithelial loss, submucosal inflammation, epithelial ulceration, urinary pyuria and response to treatment was noted. Bladder tissue histamine content and urinary prostaglandin E2 excretion were increased in the interstitial cystitis patients. Eosinophil density in bladder biopsies was low uniformly, and interstitial cystitis and control patients showed no statistical difference. In addition, serum and urinary major basic protein levels were below the accepted normal lower limits for this protein. Therefore, our study demonstrates a relationship between the mast cell and the inflammatory process of interstitial cystitis. No similar relationship was noted for the eosinophil.     

Pathology and pathophysiology of painful bladder diseases

Painful bladder disease is an ill-defined disease presenting with chronic cystitis symptoms, despite sterile urine. This report includes only patients with painful bladder diseases of unknown etiology and pathogenesis. We have chosen to classify these patients pathoanatomically as follows: interstitial cystitis, detrusor myopathy, chronic unspecific cystitis and eosinophilic cystitis. The pathoanatomical appearance of the four groups of patients are described in details and certain clinical differences appear between the groups. The etiology and pathogenesis to the inflammatory reactions and muscle changes found in the detrusor biopsies are unknown, but many theories exist. It is suggested that something in the urine gains access to the bladder wall and initiates the pathoanatomical changes through a defective urothelium and glycosaminoglycans layer. In the interstitial cystitis patients, the inflammatory process and mast cell degranulation might be monitored by the urinary excretion of 1,4-methyl-imidazole-acetic acid and eosinophil cationic protein. It is concluded that no specific therapy for the disease exists, since etiology and pathogenesis are still unknown and therefore future research in this field is very important.     

Cysteinyl leukotriene D4 increases human detrusor muscle responsiveness to histamine

PURPOSE: Leukotriene D(4) and histamine are proinflammatory mediators that are released concomitantly by activated mast cells. There is the possibility of mutual potentiation of their actions in inflammatory diseases such as interstitial cystitis. We investigated whether human detrusor smooth muscle cells showed increased responsiveness to histamine in the presence of leukotriene D(4). MATERIALS AND METHODS: Cold cup detrusor biopsies were obtained from patients undergoing cystoscopy for benign noninvasive bladder diseases. Human detrusor smooth muscle cells in culture were obtained using an explantation technique and subcultivated for a maximum of 3 passages. The cytosolic free Ca(2+) concentration and contractile force were measured by spectrofluorometry and myograph techniques, respectively. RESULTS: Low doses of leukotriene D(4) (10 nM or less), which usually do not produce a significant effect on the free Ca(2+) concentration or on muscle contraction when administered 30 to 60 seconds beforehand, significantly enhanced the transient increase in the free Ca(2+) concentration and isometric force induced by 50 to 200 nM histamine. Increased histamine responses were associated with an upward shift in the fura-2 fluorescence ratio, suggesting that histamine hyperresponsiveness was due to the appearance of additional histamine receptors on the sarcolemma or to more efficient signaling per receptor. Leukotriene D(4) concentrations greater than 10 nM had no potentiating effects. CONCLUSIONS: To our knowledge this is the first demonstration in the human detrusor that leukotriene D(4) potentiates the effect of histamine. These inflammatory mediators, which are often released concomitantly from mast cells, may interact mutually to potentiate the spasmogenic effect of histamine. These results suggest that the combination of leukotriene D(4) and histamine H1 receptor antagonists may be more effective for the treatment of interstitial cystitis than when given alone.     

INCREASED URINARY HYALURONIC ACID AND INTERSTITIAL CYSTITIS

Purpose

We compared urinary levels of hyaluronic acid in patients who met the National Institute for Diabetes, and Digestive and Kidney Diseases criteria for interstitial cystitis and in age matched healthy female controls.

Materials and Methods

Urinary hyaluronic acid was measured by solid phase radiometric assay using hyaluronic acid binding protein. Hyaluronic acid and symptom scores were compared in interstitial cystitis patients who gave multiple urine samples during treatment. Since hyaluronic acid changed with treatment in some patients, 17 samples from untreated interstitial cystitis patients were selected and compared with 17 control samples.

Results

Mean plus or minus standard deviation urinary hyaluronic acid concentrations were similar in the 2 groups (interstitial cystitis group 574 ± 496, controls 512 ± 324 ng./ml., p = 0.77). When normalized to creatinine urinary hyaluronic acid was significantly higher in interstitial cystitis patients (interstitial cystitis group 674 ± 220, controls 446 ± 220 ng./mg. creatinine, p = 0.0019). Urinary creatinine concentrations did not differ significantly (interstitial cystitis group 842 ± 715, controls 1,162 ± 516 mg./l., p = 0.12).

Conclusions

Urinary hyaluronic acid was higher in interstitial cystitis patients than healthy controls. Since bladder hyaluronic acid is below the epithelium, this finding may indicate leakage across the epithelium into the urine in interstitial cystitis patients.     

Urinary Chondroitin Sulfates, Heparan Sulfate and Total Sulfated Glycosaminoglycans in Interstitial Cystitis

Purpose

We compared urinary glycosaminoglycan levels in patients with interstitial cystitis and healthy controls.

Materials and Methods

Total sulfated glycosaminoglycans assayed by dimethylmethylene blue binding and individual glycosaminoglycans analyzed by cellulose acetate electrophoresis were compared in patients with interstitial cystitis and healthy controls. Also, multiple urine samples were obtained from healthy female controls for 2 months to assess the relationship of urinary glycosaminoglycan and creatinine concentrations, and to determine whether glycosaminoglycan excretion changes during the menstrual cycle.

Results

Total sulfated glycosaminoglycan and creatinine concentrations correlated well in random voided samples. Menstrual cycle day did not affect total sulfated glycosaminoglycan levels. Cellulose acetate electrophoresis revealed 3 bands corresponding to chondroitin sulfates, heparan sulfate and acidic glycoprotein. Patients with interstitial cystitis had decreased urinary concentrations of each of these individual components and total sulfated glycosaminoglycans. However, glycosaminoglycan-to-creatinine ratios were similar in interstitial cystitis and control urine.

Conclusions

Using these assays total and individual urinary glycosaminoglycan levels normalized to creatinine were not altered in interstitial cystitis.     

The association of elevated urinary total to sulfated glycosaminoglycan ratio and high molecular mass hyaluronic acid with interstitial cystitis

PURPOSE: A decrease in the glycosaminoglycan (GAG) layer on the urothelium is believed to be one of the possible causes of interstitial cystitis. Consequently, GAG-like substances and hyaluronic acid (HA) have been prescribed for treating this condition. To delineate the possible role of GAG and HA in the interstitial cystitis disease process, we compared the urinary levels of total GAGs (sulfated + non-sulfated), sulfated GAGs and HA in interstitial cystitis patients and normal controls. We also examined different HA species present in the urine of interstitial cystitis patients. MATERIALS AND METHODS: The total GAG and sulfated GAG levels in urine specimens of normal individuals (n = 20) and interstitial cystitis patients (n = 25) were determined by utilizing the carbazole reaction assay and the Farndale method, respectively, and were expressed as microg./mg. creatinine. Urinary HA levels were measured by applying the HA test and were expressed as ng./mg. creatinine. Gel filtration column chromatography was used to examine the profile of urinary GAGs and HA species. RESULTS: Total urinary GAGs were 2.5 to 4-fold elevated in interstitial cystitis patients with moderate to severe symptoms (Group 2; 76.2 +/- 24.8) when compared with those in normal individuals (19.9 +/- 2.5) and patients with mild symptoms (Group 1; 30.4 +/- 5.1) (p <0.001). Three urinary GAG peaks were detected in both normal and interstitial patients. However, each GAG peak from interstitial cystitis patient urine was 3 to 5-fold higher than that from normal patient urine. The sulfated GAG levels, however, remained unchanged among normal individuals (1.4 +/- 0.22), Group 1 (2.2 +/- 0.96) and Group 2 (1.6 +/- 0.38) patients (p >0.05). Consequently, the ratio of total GAGs to sulfated GAGs was elevated 3 to 3.5-fold in Group 2 patients (49.9 +/- 13.9) in comparison to that in normal individuals (16.7 +/- 2.5) and group 1 patients (14.4 +/- 4.6) (p <0.001). Urinary HA levels were marginally elevated in Group 2 patients (821. 4 +/- 247.9) when compared with those in the normal group (337.3 +/- 106.1) and Group 1 patients (540.9 +/- 166.5). In addition, a distinct high molecular mass HA species was present only in Group 2 patients. CONCLUSIONS: The increased ratio of total GAGs to sulfated GAGs and marginally elevated HA levels in urine indicate that the GAG layer is altered in interstitial cystitis patients. However, these results are in contrast to the accepted concept that a reduction in urothelial GAGs causes interstitial cystitis. The high molecular mass HA species detected in patients with severe symptoms may play a role in the pathophysiology of this disease.     

Urine eosinophil cationic protein in painful bladder disease

Urine eosinophil cationic protein (U-ECP), blood eosinophils and eosinophils in bladder biopsy specimens were studied in 30 patients with painful bladder disease (15 with detrusor mastocytosis, i.e. interstitial cystitis (IC) (greater than or equal to 28 mast cells/mm2 in the detrusor muscle) and 15 patients without detrusor mastocytosis). In patients with IC the median concentration of U-ECP was 140 arbitrary u/l versus 14 arb. u/l in the remaining patients (P less than 0.001). The mean peripheral leukocyte count was significantly lower in the IC group (P less than 0.05). Tissue infiltration with eosinophils was found in 43% of the bladder biopsies from patients with IC compared with 4% of the biopsies in the remaining patients (P less than 0.05). A negative correlation between peripheral eosinophils and U-ECP was found in the patients with IC (r = 0.52, P less than 0.05). These results suggest that eosinophils are attracted to the inflammatory site in the bladder wall where ECP is released. Eosinophils thus seem to participate actively in the inflammatory process. U-ECP seems to provide valuable diagnostic information when diagnosing IC in patients with painful bladder disease. It is suggested that ECP might be involved in the process of tissue destruction in IC.     

Role of cysteinyl leukotrienes in adenosine 5'-monophosphate induced bronchoconstriction in asthma

BACKGROUND: Adenosine induced bronchoconstriction in patients with asthma is thought to be mediated by the synthesis and release of autacoids from airway mast cells. In vitro, adenosine induced constriction of asthmatic bronchi is blocked by a combination of specific histamine and cysteinyl leukotriene receptor antagonists, but the relative contribution of these mediators in vivo is unclear. We hypothesised that adenosine induced bronchoconstriction in asthmatic patients may be blocked by pretreatment with the orally active selective cysteinyl leukotriene-1 (CysLT(1)) receptor antagonist, montelukast. METHODS: In a randomised, double blind, crossover study, oral montelukast (10 mg) or placebo was administered once daily on two consecutive days to 18 patients with mild to moderate persistent atopic asthma. Incremental doses of adenosine 5'-monophosphate (AMP) from 0.39 to 400 mg/ml were inhaled by dosimeter and the dose producing a 20% fall in FEV(1) (PC(20)AMP) after AMP inhalation was recorded. Leukotriene E(4) (LTE(4)) urinary concentrations were measured by enzyme immunoassay 4 hours after AMP challenge. RESULTS: Montelukast pretreatment provided highly significant protection against adenosine induced bronchoconstriction, with geometric mean PC(20)AMP values of 52.6 mg/ml (95% CI 35.2 to 78.7) after placebo and 123.9 mg/ml (95% CI 83.0 to 185.0) after montelukast (p=0.006). The geometric mean of the montelukast/placebo PC(20)AMP ratio was 2.4 (95% CI 1.3 to 4.2). Montelukast had no significant effect on 4 hour urinary excretion of LTE(4) compared with placebo. CONCLUSIONS: Selective CysLT(1) receptor antagonism with montelukast provides highly significant protection against AMP induced bronchoconstriction in patients with atopic asthma, implying that cysteinyl leukotrienes are generated from airway mast cells through preferential activation of their A(2B) receptors.     

Urinary Epitectin (MUC-1 Glycoprotein) in the Menstrual Cycle and Interstitial Cystitis

Purpose

We compared interstitial cystitis and control urine specimens for epitectin (MUC-1 glycoprotein), an epithelial mucin.

Materials and Methods

Urinary epitectin was measured in 28 patients with interstitial cystitis and 26 healthy controls. Ten controls provided multiple urine samples to determine whether urinary epitectin changes with the menstrual cycle.

Results

Epitectin levels were stable throughout the menstrual cycle. Interstitial cystitis cases had decreased urinary epitectin-to-creatinine ratios (mean 3.89 versus 6.38 microgram/mg. creatinine for controls, p = 0.0035) and epitectin concentrations (mean 1.96 versus 4.30 microgram/ml., respectively, p = 0.0005).

Conclusions

Decreased mean urinary epitectin levels may reflect a cause (epithelial mucin deficiency) or a consequence of interstitial cystitis.     

Exposure of healthy volunteers to swine house dust increases formation of leukotrienes, prostaglandin D2, and bronchial responsiveness to methacholine

BACKGROUND: Acute exposure of healthy subjects to swine house dust causes increased bronchial responsiveness to methacholine but no acute bronchoconstriction. The role of cysteinyl leukotrienes and mast cells in increased bronchial responsiveness is unclear. METHODS: Ten non-asthmatic subjects were exposed to swine dust for three hours while weighing pigs in a piggery. Urine was collected prior to and for up to 12 hours after entering the piggery and at the same times five days before and the day after exposure. As indices of whole body leukotriene production and mast cell activation, urinary levels of leukotriene E4 (LTE4) and 9 alpha, 11 beta-PGF2, the earliest appearing urinary metabolite of prostaglandin D2 (PGD2), were measured. Bronchial responsiveness to methacholine was determined five days before and the day after the exposure. RESULTS: Methacholine PD20FEV1 decreased from 1.32 mg (95% CI 0.22 to 10.25) before exposure to 0.38 mg (95% CI 0.11 to 1.3) after exposure (p < 0.01). Associated with the increase in bronchial responsiveness there was a significant mean difference between post- and prechallenge levels of LTE4 (difference 38.5 ng/mmol creatinine (95% CI 17.2 to 59.8); p < 0.01) and 9 alpha, 11 beta-PGF2 (difference 69 ng/mmol creatinine (95% CI 3.7 to 134.3); p < 0.05) on the day of exposure to swine dust. Swine dust exposure induced a 24-fold increase in the total cell number and a 12-fold increase in IL-8 levels in the nasal lavage fluid. The levels of LTB4 and LTE4 in nasal lavage fluid following exposure also increased 5.5-fold and 2-fold, respectively. CONCLUSIONS: The findings of this study indicate that cysteinyl leukotrienes and other mast cell mediators contribute to the development of increased bronchial responsiveness following inhalation of organic swine dust.     

Bladder stretch alters urinary heparin-binding epidermal growth factor and antiproliferative factor in patients with interstitial cystitis

PURPOSE: The etiology of interstitial cystitis is unknown. Urine from patients with interstitial cystitis has been shown to inhibit urothelial proliferation through a putative antiproliferative factor and to contain decreased levels of heparin-binding epidermal growth factor-like growth factor (HB-EGF) compared to controls. Stretch of detrusor smooth muscle cells is known to stimulate HB-EGF production. Because bladder hydrodistention sometimes alleviates the symptoms of interstitial cystitis, we determined whether the stretch stimulus of hydrodistention alters antiproliferative factor activity and/or HB-EGF in interstitial cystitis urine specimens. MATERIALS AND METHODS: Urine was collected immediately before, and 2 to 4 hours and 2 weeks after hydrodistention from 15 patients with symptoms and cystoscopic findings compatible with interstitial cystitis and 13 controls. Hydrodistention was performed with the subject under general or regional anesthesia and bladders were distended to 80 cm. water 3 times. Urinary HB-EGF was measured by enzyme-linked immunosorbent assay and urinary antiproliferative factor activity was determined by measuring 3H-thymidine uptake by normal human bladder urothelial cells. RESULTS: Hydrodistention significantly increased urinary HB-EGF in patients with interstitial cystitis toward normal control values (before distention p = 0.003, 2 weeks after distention p = 0.67). Urine antiproliferative factor activity decreased significantly after hydrodistention in patients with interstitial cystitis. However, antiproliferative factor activity in interstitial cystitis and control specimens was still statistically different 2 weeks after distention (before distention p = 0.0000004, 2 weeks after distention p = 0.04). CONCLUSIONS: Bladder stretch increased HB-EGF and conversely reduced antiproliferative factor activity in urine from patients with interstitial cystitis but not controls up to 2 weeks after distention. These results provide additional evidence for the possible role of antiproliferative factor and decreased HB-EGF in the pathophysiology of interstitial cystitis. To our knowledge this is also the first human study to show that in vivo bladder stretch can alter urinary factors that regulate cell growth.     

Do women with idiopathic sensory urgency have early interstitial cystitis?

Interstitial cystitis is rarely considered as a cause of urinary symptoms in referrals to gynaecology clinics. Recent concepts in the diagnosis of this condition mean that it is emerging as a much more common entity, with both early and late forms of the disease being described. Mast cell density in the detrusor muscle has been reported to be useful as a disease marker to substantiate the diagnosis of interstitial cystitis where no classical diagnostic features exist. We assessed mast cell counts in bladder biopsies from 27 women with idiopathic sensory urgency and 10 control patients about to undergo a colposuspension procedure for pure genuine stress incontinence; 30% of the study group had a clear increase in the detrusor muscle mast cell population (detrusor mastocytosis). No control patient showed such an increase. Early interstitial cystitis should be considered as a possible cause of lower urinary tract symptoms in patients with apparently idiopathic sensory urgency.     

Effect of a 5-lipoxygenase inhibitor on leukotriene generation and airway responses after allergen challenge in asthmatic patients.

The effect of a single oral dose (800 mg) of zileuton (A-64077), a specific 5-lipoxygenase inhibitor, on the early and late airway responses to inhaled allergen was studied in a randomised, double blind, placebo controlled, and crossover trial in nine subjects with atopic asthma. Leukotriene generation was also assessed in vivo by measuring urinary leukotriene (LT) E4 excretion, and ex vivo by measuring calcium ionophore stimulated whole blood LTB4 production. Zileuton almost completely inhibited ex vivo LTB4 production but reduced urinary excretion of LTE4 by only about half. There was a trend for the early asthmatic response to be less on the day of zileuton treatment, but this did not reach statistical significance (p = 0.08). The zileuton induced reduction in maximum fall in FEV1 in the early asthmatic response was, however, significantly related to the reduction in urinary LTE4 excretion (r = 0.8), but not to the reduction in LTB4 generation ex vivo. There was no significant change in the allergen induced late asthmatic response, or in the increase in airway responsiveness to methacholine following antigen. The results provide some support for the hypothesis that the cysteinyl leukotrienes have a role in the allergen induced early asthmatic response. More complete in vivo inhibition of 5-lipoxygenase may be needed to produce a significant reduction in airway response to allergen challenge.     

The clinical significance of eosinophils in urine]

The clinical significance of eosinophils in urine was examined. Eosinophils were found in 9 out of 10 cases of interstitial cystitis, and there were more than 50 eosinophils in 50 fields in 6 of these cases. Although the number of eosinophils almost correlated with the number of leucocytes, the relationship between eosinophils and leucocytes in interstitial cystitis was different in acute and chronic cystitis. Since urinary eosinophils could be observed in cases of interstitial cystitis in which leucocytes were as low as 3 to 10 per field and the number of eosinophils was not decreased by chemotherapy, the urinary eosinophils in interstitial cystitis may be of allergic significance and reflect eosinophilic infiltration into the bladder wall.     

Characteristics of mast cells in normal bladder, bacterial cystitis and interstitial cystitis.

An analysis was made of the numbers and characteristics of mast cells in lateral bladder wall biopsies from 22 patients with interstitial cystitis, 6 with bacterial cystitis and 8 normal controls, using toluidine blue stains and computerised video image analysis techniques. A significantly greater number of mast cells were found within the detrusor muscle in interstitial cystitis than in bacterial cystitis or normal controls. Within the urothelium and submucosa, mast cell numbers were significantly greater than in normal controls in both interstitial and bacterial cystitis. In interstitial cystitis mast cells were significantly larger within the detrusor than in the urothelium/submucosa and they appeared to degranulate predominantly within the superficial layers. Differential staining techniques, using long and short toluidine blue stains, failed to reveal statistically significant evidence of mast cell heterogeneity within the bladder wall in interstitial cystitis.     

Interstitial cystitis is associated with intraurothelial Tamm-Horsfall protein

A defective barrier between the urine and urothelium has been suggested as an etiology for interstitial cystitis. With immunohistochemical techniques we assayed the bladder biopsies of 14 interstitial cystitis patients and 10 normal controls for intraurothelial Tamm-Horsfall protein to assess indirectly the in vivo permeability of the urothelium. Eight pathological controls, including bladder biopsies from 3 patients with inflammation owing to infection or catheterization and biopsies of 5 transitional cell carcinomas of the bladder, also were assayed. Superficial intraurothelial Tamm-Horsfall protein was identified in the biopsies from 10 of 14 interstitial cystitis patients (71 per cent) but only 1 of 10 controls (10 per cent) (p less than 0.01). Tamm-Horsfall protein was not identified in biopsies from the pathological controls. In 6 of 7 cases when more than 1 biopsy was available for analysis the findings were identical in each specimen. There was a direct correlation between the density of detrusor mast cells and the demonstration of intraurothelial Tamm-Horsfall protein. Seven of the 9 evaluable interstitial cystitis patients with intraurothelial Tamm-Horsfall protein but only 1 of 4 without intraurothelial Tamm-Horsfall protein experienced a favorable response to intravesicle oxychlorosene sodium (p greater than 0.05). These data suggest that abnormal permeability of the urothelium is associated with and a possible cause of interstitial cystitis and that the demonstration of intraurothelial Tamm-Horsfall protein in bladder biopsy specimens may prove to be useful as a diagnostic test for interstitial cystitis.     

Interstitial cystitis in a woman with systemic mastocytosis

Studies have reported detrusor mastocytosis in patients with interstitial cystitis. The author describes a patient with systemic mastocytosis who was confirmed to have detrusor mastocytosis and interstitial cystitis. She responded to therapy with pentosanpolysulfate. The literature on systemic mastocytosis and the role of mast cells in the pathophysiology of interstitial cystitis are reviewed.     

THE URINARY GLYCOPROTEIN GP51 AS A CLINICAL MARKER FOR INTERSTITIAL CYSTITIS

PURPOSE: GP51 is a urinary glycoprotein with a molecular weight of 51 kDa. This glycoprotein is produced and secreted by the transitional epithelium of the genitourinary tract, and has been isolated from human urine. Studies have demonstrated that GP51 levels are decreased in bladder biopsies of patients with interstitial cystitis. We evaluated urinary GP51 in a noninvasive manner as a clinical marker of interstitial cystitis. MATERIALS AND METHODS: Urinary GP51 levels were measured using antigen inhibition enzyme-linked immunosorbent assay. In blinded fashion we analyzed for quantitative differences 24-hour urine samples of 36 patients with interstitial cystitis and 23 normal controls who were age matched within 5 years (mean age 47.3). We also evaluated GP51 in random urine specimens of 17 normal controls, 14 patients with interstitial cystitis and 11 subjects who had undergone cystectomy to determine whether urinary GP51 is mainly produced by the bladder, which is the site of interstitial cystitis. To ascertain the specificity of urinary GP51 to interstitial cystitis urine samples of 34 patients with other urological diseases were measured and compared with findings in the samples of 15 with interstitial cystitis. RESULTS: Low GP51 levels appeared to be unique to the interstitial cystitis state compared to normal (p = 0.008). GP51 in patients with interstitial cystitis and in those who underwent cystectomy was lower (p < 0.001) than in normal controls. These findings suggest that the major source of urinary GP51 is the bladder. Also, we observed lower GP51 levels in interstitial cystitis than in other urinary tract diseases (p < 0.0001). CONCLUSIONS: Our study substantiates the possibility of using GP51 as a clinical marker for diagnosing interstitial cystitis by a noninvasive urinary assay.     

Autorosette inhibition factor: a positive acute phase reactant in interstitial cystitis

Autorosette inhibition factor (AIF), complement C3d and eosinophil cationic protein (ECP) in urine were determined in 28 patients with painful bladder disease. In patients with interstitial cystitis (IC), diagnosed by the demonstration of detrusor mastocytosis, a positive correlation (r = 0.73, p less than 0.01) between AIF and C3d was found, whereas no reliable correlation was found in the remaining patients. The median concentration of urinary ECP was significantly elevated in the group of patients with IC whereas the median concentration of C3d was significantly elevated in both groups. AIF seems to behave as a positive acute phase reactant in IC. It is hypothesized that AIF may play a role in the pathogenesis of IC by influencing the normal barrier function of the epithelium of the bladder.