Свръхактивен пикочен мехур

Interstitial cystitis is a clinical syndrome characterized by daytime and nighttime urinary frequency, urgency, and pelvic pain. Interstitial cystitis has no clear etiology or pathophysiology, and diagnostic criteria for the syndrome remain undefined. Despite considerable research, universally effective treatments do not exist; therapy usually consists of various supportive, behavioral, and pharmacologic measures. Surgical intervention is rarely indicated. [1]

The International Continence Society has coined the term painful bladder syndrome (suprapubic pain with bladder filling associated with increased daytime and nighttime frequency, in the absence of proven urinary infection or other obvious pathology) and reserves the diagnosis of interstitial cystitis for patients with characteristic cystoscopic and histologic features of the condition. [2]

An international consensus panel was able to generally agree on the following definition of interstitial cystitis/bladder pain syndrome (IC/BPS): unpleasant sensation (pain, pressure, discomfort) perceived to be related to the urinary bladder and associated with lower urinary tract symptoms of more than 6 weeks' duration, in the absence of infection or other identifiable causes. American Urological Association (AUA) guidelines published in 2011 and amended in 2014 use an evidence-based approach to provide a clinical framework for the diagnosis and management of this condition. [3] The Canadian Urological Association issued a guideline on diagnosis and treatment of IC/BPS in 2016. [4]

Despite years of intensive research, there are no specific clinical or urinary markers currently clinically available; no absolutely specific radiographic, laboratory, or serologic findings; and no biopsy patterns that are pathognomonic for interstitial cystitis. The syndrome remains a diagnosis of exclusion (see Presentation, DDx, and Workup.)

Intensive study has been done to attempt to identify biomarkers for IC/BPS. Some interesting studies have shown that bladder nitric oxide is an accurate marker for Hunner lesions, but these are not present in all patients, and the test requires specific equipment, which has limited its widespread clinical use. [5] Differences in levels of cytokines and chemokines, specifically CXCL-10, have shown some ability to differentiate patients with and without Hunner lesions. [6] Other studies of ulcerative IC/BPS have shown that numerous other cytokines and chemokines are up-regulated as well, heralding a possible urinary test to identify patients. [7]

Perhaps the most promising urinary biomarker for IC/BPS is antiproliferative factor (APF). [8] This small 8–amino-acid peptide has been associated with suppression of cell growth, increases in transcellular permeability, and lowering of levels of proteins that form intercellular junctional complexes. APF is synthesized and secreted by bladder epithelial cells from patients with IC/BPS and may play a key role in pathophysiology. [9] In vitro studies have shown that removal of APF from cell culture media restored cell proliferation and membrane integrity. [10] Studies have also suggested a role for APF in the therapeutic effect of hydrodistension in patients with IC/BPS, although further confirmatory studies are necessary. [11]

Treatment
The most important element in treating patients with interstitial cystitis is education and emotional support. Periodic exacerbations are managed as they occur because no long-term therapy has been shown to prevent or delay recurrent episodes. Therefore, the purpose of treatment is to palliate and alleviate symptoms.

Because no discrete pathognomonic pathologic criteria exist for assessing and monitoring disease severity, indications and goals for treatment are based on the degree of patient symptoms. Assessing patient response to treatment is also complicated because of the subjective nature of symptoms; the waxing and waning nature of symptoms without treatment; and the lack of objective serologic, physical, or histopathologic findings. Conservative measures and oral or intravesical treatments are considered first-line treatment.