Etiology, pathogenesis, and diagnosis of interstitial cystitis

Interstitial cystitis (IC) is a bladder syndrome of unknown etiology. The cause of IC is most likely multifactorial and includes genetic and environmental factors. Various pathophysiological changes in the bladder, pelvis, and peripheral and central nervous systems have been identified, and this has led to the emergence of biologically specific treatment modalities. Interstitial cystitis is being diagnosed with increasing frequency; however, current diagnostic criteria are non-uniform, and there is significant overlap between chronic pelvic pain syndromes in men and women, interstitial cystitis, recurrent "cystitis," and the overactive bladder syndrome. The diagnosis of interstitial cystitis can be made clinically and by cystoscopy and hydrodistension. The sensitivity and specificity of urinary markers and the potassium sensitivity test have not been prospectively studied.     

Diagnosis of interstitial cystitis/ painful bladder syndrome in patients with overactive bladder symptoms

Overactive bladder (OAB) and interstitial cystitis (IC) have similar symptoms, including urinary urgency/frequency and nocturia, making them difficult to differentiate on the basis of clinical presentation alone. Both conditions may represent a clinical manifestation of a hypersensitive bladder and should be included in the differential diagnosis for patients who present with urgency/ frequency. It is especially important that IC be considered in patients with OAB that is refractory to treatment. The proposed diagnostic framework may be useful for differentiating IC from OAB and for facilitating appropriate treatment.     

A型肉毒素在间质性膀胱炎治疗中的研究进展

间质性膀胱炎（interstitial cystitis,IC）好发生于30-70岁女性,平均43岁,美国妇女的发病率为197／10万,而男性发病率为41／10万。国内尚无明确的流行病学统计资料。间质性膀胱炎严重影响着患者的生活质量,其发病率高,但发病原因和发病机理至今仍未明确。近年来,随着国内外学者对肉毒素进行深入和广泛的研究,提出了A型肉毒素在间质性膀胱炎的新疗法。本文就A型肉毒素在问质性膀胱炎治疗中的研究进展进行综述,临床医师实际工作中参考应用。     

A Case Control Study Reveals that Polyomaviruria Is Significantly Associated with Interstitial Cystitis and Vesical Ulceration

Objectives

To investigate whether polyomaviruses contribute to interstitial cystitis pathogenesis.

Subjects and Methods

A prospective study was performed with 50 interstitial cystitis cases compared with 50 age-matched, disease-free controls for the frequency of polyomaviruria. Associations between polyomaviruria and disease characteristics were analysed in cases. Polyomavirus in urine and bladder tissue was detected with species (JC virus vs. BK virus) specific, real-time PCR.

Results

Case patients were reflective of interstitial cystitis epidemiology with age range from 26–88 years (median 58) and female predominance (41/50 F). There was a significant increase in the frequency of polyomavirus shedding between cases and controls (p<0.02). Polyomavirus shedding, in particular BK viruria, was associated with vesical ulceration, a marker of disease severity, among interstitial cystitis cases after adjustment for age and sex (OR 6.8, 95% CI 1.89–24.4). There was a significant association among cases between the presence of BK viruria and response to intravesical Clorpactin therapy (OR 4.50, 95% CI 1.17–17.4).

Conclusion

The presence of polyomaviruria was found to be associated with the ulcerative form of interstitial cystitis. Clorpactin, which has anti-DNA virus activity, was more likely to improve symptoms in the presence of BK viruria. These data from this pilot study suggest associations between polyomaviruria and interstitial cystitis warranting further investigation.     

Treatment approaches for interstitial cystitis: multimodality therapy

Interstitial cystitis is an increasingly common disease characterized by urgency, frequency, and pelvic pain. Its etiology is poorly understood but is likely to be multifactorial. A proposed pathophysiology describing a cascade of events, including epithelial dysfunction, mast cell activation, and neurogenic inflammation, is presented. Using this model, multimodality therapy regimens have been developed that treat all components of this cascade. Multimodality therapy appears more effective than single agents in the treatment of interstitial cystitis.     

A型肉毒素在间质性膀胱炎治疗中的研究进展

间质性膀胱炎(interstitial cystitis,IC)好发生于30～70岁女性,平均43岁,美国妇女的发病率为197/10万,而男性发病率为41/10万。国内尚无明确的流行病学统计资料。间质性膀胱炎严重影响着患者的生活质量,其发病率高,但发病原因和发病机理至今仍未明确。近年来,随着国内外学者对肉毒素进行深入和广泛的研究,提出了A型肉毒素在间质性膀胱炎的新疗法。本文就A型肉毒素在间质性膀胱炎治疗中的研究进展进行综述,临床医师实际工作中参考应用。     

Superoxide dismutase for therapeutic use: Clinical experience,dead ends and hopes

Summary The clinical trials performed with bovine superoxide dismutase (SOD) are reviewed. SOD, applied intraarticularly at a dosage of 2–16 mg, proved to be effective in osteoarthritis of the knee joint in three placebo-controlled and one steroid-controlled double-blind trials. Its efficacy in other inflammatory joint disorders is documented by uncontrolled trials. Similarly, some controlled and many open studies support the efficacy of locally injected SOD in periarticular inflammation. Systemic treatment of rheumatoid arthritis by SOD at the dosages indicated yielded disappointing results. Well documented, though open uncontrolled studies demonstrated beneficial effects of locally administered SOD in radiation cystitis, interstitial cystitis and Peyronie's disease. Tolerance is good, but allergic reactions at low incidence have to be anticipated. Human SOD derived from recombinant microorganisms is being developed to explore its therapeutic potential particularly in ischemia-reperfusion damage, adult respiratory distress or similar conditions.     

Interstitial cystitis-epidemiology, diagnostic criteria, clinical markers

Knowledge of the epidemiology of interstitial cystitis (IC), the burden of the disease in the population, and the identification of possible risk factors remains largely fragmentary. The most reliable information comes from the few population-based studies that have appeared in the literature over the past 25 years, but two major issues urgently need to be addressed by appropriate epidemiologic studies: although studies find that only 10% of IC occurs in men, the hallmark symptoms of chronic prostatitis-pelvic pain, voiding dysfunction, and pain associated with sexual activity-overlap with those in men who carry the IC diagnosis. In addition, it is not known whether children suffer from the condition. The definition of IC is grounded in the symptomatology of pelvic pain and urinary frequency of a chronic nature and unexplained by any known urologic or other system pathology, but undue reliance on cystoscopic criteria has undoubtedly led to significant underdiagnosis. Efforts to identify clinical markers for diagnosis of IC are continuing and may lead the way to ascertaining the etiology and pathophysiology of IC.     

Topical use of cortisone in urology

Cortisone was instilled into the bladder in the treatment of interstitial cystitis and contracted bladder, trigonitis and urethritis in females, nonspecific urethritis in males, and inflammation of the wall of the bladder. In infectious cases the hormonal therapy was used after antibacterial measures had failed. Improvement occurred quickly in most cases soon after cortisone therapy was given. In a few cases of interstitial cystitis and contracted bladder the relief obtained was inadequate and it was necessary to carry out overdistention procedures under visualization. When that was done, however, it was noted that the condition of the bladder was improved as compared with the conditions usually observed in cases in which cortisone treatment is not given before the procedure. Results of tests of the blood during therapy indicated that the benefits of the treatment were not owing to systemic absorption of cortisone.     

Interstitial cystitis and lower urinary tract symptoms in males and females-the combined role of potassium and epithelial dysfunction

Evidence of a lower urinary tract dysfunctional epithelium has been detected in women and men with interstitial cystitis and other complexes of lower urinary tract symptoms. Lower urinary tract dysfunctional epithelium can affect the bladder, the urethra, the labia or vaginal introitus in women, and the prostatic ducts and urethra in men. Because an individual with lower urinary tract dysfunctional epithelium may experience pain in one or more locations throughout the pelvis in any combination, the clinician cannot reliably establish a diagnosis based on "where it hurts." A useful diagnostic tool is the intravesical potassium sensitivity test, which detects the abnormal epithelial permeability of lower urinary tract dysfunctional epithelium. In most cases, lower urinary tract dysfunctional epithelium can be treated successfully.     

Challenges and Opportunities in Radiation-induced Hemorrhagic Cystitis

As diagnosis and treatment of cancer is improving, medical and social issues related to cancer survivorship are becoming more prevalent. Hemorrhagic cystitis (HC), a rare but serious disease that may affect patients after pelvic radiation or systemic chemotherapy, has significant unmet medical needs. Although no definitive treatment is currently available, various interventions are employed for HC. Effects of nonsurgical treatments for HC are of modest success and studies aiming to control radiation-induced bladder symptoms are lacking. In this review, we present current and advanced therapeutic strategies for HC to help cancer survivors deal with long-term urologic health issues.     

cDNA cloning and characterization of a novel nucleolar protein.

In an initial study of anti-nuclear antibodies in the chronic inflammatory bladder disease interstitial cystitis, we reported that 7% of interstitial cystitis patients studied had autoantibodies to the nucleolus. We now report that, using an autoimmune serum from a patient with interstitial cystitis, we have identified and partially characterized a novel protein with an M(r) of approximately 55 kDa (hereafter referred to as No55) localized to the granular component of the nucleolus. No55 was initially characterized by diffuse nucleolar immunofluorescence staining in interphase cells and by Western blotting as a 55-kDa doublet on whole-cell extracts. During mitosis, No55 was associated with chromosomes and appeared in prenucleolar bodies during telophase, but it did not colocalize with p80-coilin in coiled bodies. Immunoelectron microscopy revealed that No55 was localized uniformly throughout the granular component of the nucleolus compared with a more peripheral localization of nucleolar granular component protein B23. On segregation of the nucleolus with actinomycin D, No55 remained with the granular component of the segregated nucleolus, whereas protein B23 was found predominantly in the nucleoplasm. Finally, a cDNA expression library was screened with the human autoantibody against No55, and a 2.4-kb insert was isolated, subcloned to homogeneity, and then sequenced. Analysis of this sequence showed an open reading frame of approximately 1.3 kb coding for 437 amino acids with a predicted molecular weight of 50 kDa. A search of the gene sequence database indicated homology with SC65, a rat synaptonemal complex protein. Therefore, on the basis of molecular weight, nucleolar sublocalization, response to actinomycin D, and cDNA sequence determination, No55 is a novel protein of the interphase nucleolus.     

Painful interactions: Microbial compounds and visceral pain

Visceral pain, characterized by abdominal discomfort, originates from organs in the abdominal cavity and is a characteristic symptom in patients suffering from irritable bowel syndrome, vulvodynia or interstitial cystitis. Most organs in which visceral pain originates are in contact with the external milieu and continuously exposed to microbes. In order to maintain homeostasis and prevent infections, the immune- and nervous system in these organs cooperate to sense and eliminate (harmful) microbes. Recognition of microbial components or products by receptors expressed on cells from the immune and nervous system can activate immune responses but may also cause pain. We review the microbial compounds and their receptors that could be involved in visceral pain development.     

The role of pentosan polysulfate in treatment approaches for interstitial cystitis

Studies of the mechanisms and causes of interstitial cystitis (IC) and of the properties of pentosan polysulfate have provided a scientific rationale for using pentosan polysulfate to treat IC. In randomized, double-blind studies, patient and investigator evaluations of pentosan polysulfate in the treatment of IC resulted in favorable assessments of the drug. In addition, IC patients in two out of four randomized, prospective trials improved significantly in most variables with treatment by oral pentosan polysulfate; in the two other studies, the IC patients improved in some domains with pentosan therapy, although not significantly. Importantly, two longer-term, patient-evaluation studies showed that a longer duration of treatment with pentosan polysulfate resulted in greater improvements in patients' response rates and outcomes. The results indicate that treatment should be continued for 6 months or longer in order to show significant improvement. Of particular interest are studies suggesting that a potassium test may possibly predict the response of IC patients to treatment with pentosan polysulfate.     

Economics of interstitial cystitis in clinical practice

Urologists may be concerned that treatment of patients with interstitial cystitis (IC) is not economically feasible, and the time spent on these patients could be used for more profitable urologic therapy. However, care of IC patients can provide urologic practices with increased revenue opportunities through a wide range of procedures, including IC evaluation and management, treatment planning, and diagnostic, therapeutic, and even surgical techniques. Current Procedural Terminology (CPT) and evaluation and management (E&M) charge codes are provided for many types, levels, and complexities of IC procedures. Some of these treatments may use physician extenders who generate profits without additional overhead costs. Further, IC therapy may involve the use of many in-office services, such as urodynamics, biofeedback, and peripheral nerve stimulation that can be economically profitable. Rather than being an economic drain, patients with IC can enhance the profitability of a urologic practice while they receive much needed care.     

State of the art in intravesical therapy for lower urinary tract symptoms

Intravesical therapy is the routine first-line treatment for effectively delaying or preventing the recurrence of bladder cancer. This route of drug administration has also shown tremendous promise in the treatment of interstitial cystitis/painful bladder syndrome (IC/PBS) and potentially overactive bladder to justify investments for further improvements. This review takes a bird's eye view into the current status of intravesical therapy, with emphasis on liposomal nanoparticles, in diseases associated with lower urinary tract symptoms (LUTS). Ongoing efforts to advance the field of intravesical drug delivery include development of sustained-release drug implants and efforts to improve delivery of biotechnological products including large protein acting as neurotoxins and small interfering RNAs.     

Revisiting the Role of Potassium Sensitivity Testing and Cystoscopic Hydrodistention for the Diagnosis of Interstitial Cystitis

Objectives

To revisit the diagnostic roles of cystoscopic hydrodistention and the potassium sensitivity test (PST) for the diagnosis of interstitial cystitis (IC).

Methods

We prospectively enrolled 214 patients clinically diagnosed with IC, 125 non-IC patients who underwent video urodynamic studies and PST, and another 144 non-IC patients who underwent cystoscopic hydrodistention before transurethral surgery. The sensitivity, specificity, and positive and negative predictive values were calculated for the PST and glomerulations after cystoscopic hydrodistention.

Results

After cystoscopic hydrodistention, glomerulations developed in 211/214 (98.6%) IC patients and 61/144 (42.4%) of the non-IC patients including patients with stones (45/67, 67%), hematuria (2/5, 40%), and stress urinary incontinence (SUI) (6/17, 35%). When positive glomerulation was defined as grade 2 or more, the sensitivity was 61.7%. The PST was positive in 183/214 (85.5%) IC patients and 7/17 (41%) with hypersensitive bladder, 7/32 (22%) with detrusor overactivity, 5/27 (18%) with SUI, 2/21 (10%) with lower urinary tract symptoms, and 2/25 (8%) with bladder outlet obstruction. The PST had a sensitivity of 85.5% and a specificity of 81.6% for diagnosis of IC. IC patients with a positive PST had a significantly smaller urgency sensation capacity, smaller voided volume, and greater bladder pain score.

Conclusions

Both the PST and glomerulations after hydrodistention are sensitive indicators of IC, but the specificity of glomerulations in the diagnosis of IC is lower than that of the PST. A positive PST is associated with a more hypersensitive bladder and bladder pain, but not the grade of glomerulations in IC patients. Neither test provided 100% diagnostic accuracy for IC, we might select patients into different subgroups based on different PST and hydrodistention results, not for making a diagnosis of IC but for guidance of different treatments.     

Blockade of NGF and trk receptors inhibits increased peripheral mechanical sensitivity accompanying cystitis in rats

Visceral inflammation, including that arising from bladder inflammation, reduces the threshold to sensation of innocuous or noxious stimuli applied to peripheral structures (referred hyperalgesia). Cystitis may induce transient or persistent plastic changes mediated by neurotrophins, particularly nerve growth factor (NGF), which contribute to increased nociceptive input. In this study, acute or subacute cystitis was induced in female rats by one or three (at 72-h intervals) 400-microl intravesical instillations of 1 mM acrolein. Sensitivity of the hindpaws to mechanical and thermal stimuli was determined before and 4, 24, 48, 72, and 96 h after treatment. Other groups of rats were treated with intravesical or intrathecal k252a [a nonspecific antagonist of tyrosine kinase (trk) receptors, including trkA, the high-affinity receptor for NGF] before the first or third acrolein instillation. Some rats were intraperitoneally injected with specific NGF-neutralizing antiserum or normal serum before acrolein instillation. Acute and subacute cystitis induced mechanical, but not thermal, referred hyperalgesia that was attenuated by intravesical pretreatment with k252a. Systemic treatment with NGF-neutralizing antiserum before instillation of acrolein suppressed subsequent mechanical referred hyperalgesia. Expression of NGF was increased within the bladder by acute or subacute cystitis and in L6/S1 dorsal root ganglia by subacute cystitis. These results suggest that the bladder-derived NGF acting via trk receptors at least partially mediates peripheral sensitization to mechanical stimuli associated with acute and subacute acrolein-induced cystitis.     

p53 mediates interstitial cystitis antiproliferative factor (APF)-induced growth inhibition of human urothelial cells

Antiproliferative factor (APF) is a sialoglycopeptide elevated in the urine of patients with interstitial cystitis, a urinary bladder disorder of unknown etiology that is characterized by chronic pelvic pain. The present study was directed toward uncovering a pathway through which APF signals. Treatment of human urothelial cells with native APF resulted in growth inhibition accompanied by blockade of cell cycle transit and increased p53. Reduced expression of p53 by RNA interference diminished, while ectopic expression of p53 mimicked, the effects of APF. These are the first findings implicating the network of p53 target genes in urothelial defects associated with interstitial cystitis.     

Detrusor Myocyte Autophagy Protects the Bladder Function via Inhibiting the Inflammation in Cyclophosphamide-Induced Cystitis in Rats

Autophagy, a highly conserved homeostatic cellular process that removes and recycles damaged proteins and organelles in response to cellular stress, is believed to play a crucial role in the immune response and inflammation. The role of autophagy in bladder cystitis, however, has not well been clarified. Here we investigate the role of detrusor myocytes autophagy (DMA) in cyclophosphamide-induced cystitis animal model. 164 female Sprague-Dawley rats were randomized into three experimental groups and compared to three control groups, respectively. The expressions of microtubule-associated protein 1 light chain 3 (LC3), p-p70s6k (the phosphorylated form of ribosomal protein S6), SOD2 (superoxide dismutase 2) in the bladder muscular layer were measured using western blot. The co-location of LC3, alpha-smooth muscle actin (α-SMA), and autophagic vacuoles were investigated with double-labeled immunofluorescence and transmission electron microscopy (TEM). The expression of lL-1β, IL-6, IL-8, malondialdehyde (MDA), and glutathione (GSH) in the detrusor layer were analyzed using ELISA. The bladder inflammation and the number of mast cells in the muscular layer were analyzed by histology. The bladder function was evaluated using cystometry. In cyclophosphamide-induced cystitis, autophagy was detected in detrusor myocytes by increased LC3, p-p70s6k expression, and autophagosomes. However, the presence of enhanced inflammation and oxidative stress in the cyclophosphamide-treated group suggest autophagy of detrusor myocytes may not be sufficiently activated. Inflammation and oxidative stress were significantly decreased and the bladder histology and micturition function were significantly improved with rapamycin (RAPA, autophagy agonist) pre-treatment. In contrast, inflammation and oxidative stress were dramatically increased and the bladder histology and function were negatively affected with chloroquine (CQ, autophagy blocker) pre-treated. These findings preferentially provide evidence of the association between DMA and cyclophosphamide-induced cystitis in rats. The autophagy agonist RAPA significantly decreased the inflammation and protected the bladder function, which might be considered as a potential treatment for interstitial cystitis.