Classification, Characterization, and Sub-Grouping of Interstitial Cystitis
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Purpose of Review
Interstitial cystitis (IC) and IC-related conditions such as painful bladder syndrome (PBS), bladder pain syndrome (BPS), and hypersensitive bladder (HSB) have a similar symptomatic profile but probably different etiologies. A reasonable classification of these diseases/conditions is mandatory for clinical and investigational progress. We reviewed definition of current terminology and recent research evidence regarding IC and related conditions to propose a sensible classification system.
The condition with Hunner lesions (Hunner type IC: HIC) is obviously distinct from other categories in terms of histopathology, gene expression, and clinical management; HIC is a bladder-centric disease with heavy inflammation, epithelial denudation, and oligoclonal B cell expansion. Presence of glomerulations or mucosal bleeding after distension appears of least clinical significance. Classification should thus clearly differentiate the condition with Hunner lesions from those without Hunner lesions. The term covering patients as a whole should contain IC, since IC is historically a well-known name and used for insurance reimbursement.
The proposed classification/taxonomy features an umbrella term (IC/BPS) and two sub-groups, HIC (IC/BPS with Hunner lesions) and BPS (IC/BPS without Hunner lesions). IC/BPS is convenient for the initial management of symptomatic patients, and sub-groups can categorize the patients for the specific management. The characteristic symptom profile of bladder pain, urinary urgency, and increased urinary frequency is to be collectively termed as hypersensitive bladder symptoms.
KeywordsInterstitial cystitis Classification Bladder pain syndrome Hypersensitive bladder Pathophysiology
Compliance with Ethical Standards
Conflict of Interest
Yukio Homma has received speaker honorarium from Astellas, Nippon Chemiphar, and Pfizer, outside the submitted work.
Yasuhiko Igawa has received grants from Kissei, Kyorin, RaQualia, Nippon-Shinyaku, Astellas, Lilium Otuka, Takeda, Tsukada Research Medical, Integral, and Medicon, outside the submitted work. Yasuhiko Igawa has received speaker honorarium from Kissei, Kyorin, Nippon-Shinyaku, Astellas, outside the submitted work.
Yoshiyuki Akiyama, Aya Niimi, and Akira Nomiya declare that they have no conflict interests.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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