Interstitial cystitis (IC) and hypersensitive bladder (HSB) have a common lower urinary tract symptom profile called as hypersensitive bladder symptoms, such as bladder pain/discomfort, urinary urgency, or high frequency. IC and HSB are to be classified by the endoscopic presence of the Hunner lesions (Hunner type IC, HIC), presence of mucosal bleeding after distension (MBAD) and absence of the Hunner lesions (non-Hunner type IC, NHIC) or absence of both the Hunner lesions and MBAD (HSB), respectively [1]. However, it has been reported that clinical phenotyping could not segregate HIC, NHIC, and HSB due to the similar symptomatic profiles [2]. The aim of this study was to compare the clinical manifestations of patients with HIC, NHIC and HSB.

Clinical records of female patients with IC or HSB who underwent the hydrodistension at our institution from December, 2008 to December, 2017 were retrospectively reviewed. Age, comorbidity, bladder capacity at hydrodistension, symptom severity before and after hydrodistension measured by O’Leary–Sant’s symptom and problem indexes (OSSI and OSPI), and the visual analog scale (VAS) for pain were compared among HIC, NHIC, and HSB.

A total of 134 female patients with HIC (N=87), NHIC (N=33) and HSB (N=14) were evaluated. Patients with HIC were oldest and significantly older than those with NHIC. Patients with HIC had significantly higher OSSI than those with HSB, and smaller bladder capacity at hydrodistension than those with NHIC or HSB. The global response rate to hydrodistension (with or without fulguration) was highest in patients with HIC (89%), followed by those with HSB (57%) and NHIC (44%) (Table 1). Regarding comorbidities, diabetes mellitus and psychiatric disorders, respectively, were significantly more frequent in patients with HIC and in those with NHIC than the other two (Table 2).

Patients with HIC were more aged and symptomatic, and showed better responses to hydrodistension compared to those with NHIC or HSB. There were almost　no clinical parameters different between NHIC and HSB.

Clinical characters were distinct in HIC, while indistinguishable between NHIC and HSB.

Homma Y, Ueda T, Tomoe H, et al. Clinical guidelines for interstitial cystitis and hypersensitive bladder updated in 2015. Int J Urol 2016; 23: 542-549
Homma Y. Hypersensitive bladder: A solution to confused terminology and ignorance concerning interstitial cystitis. Int J Urol 2014; 21 (suppl 1): 43-47