IC/BPS has more than 1 phenotype: A need for consensus to move forward

Gopal H. Badlani, MD

The term interstitial cystitis/bladder pain syndrome (IC/BPS) describes a heterogeneous lower urinary tract disorder that is challenging to diagnose and notoriously difficult to manage effectively. There continues to be an urgent need to advance our understanding of IC/BPS that would include the characterization of specific patient subgroups, the cellular and molecular mechanisms that underlie the bladder’s inability to repair itself, and the etiology of disease progression so that a more evidence-based, patient-centered approach to diagnosis and treatment can be realized.

Clinical phenotyping and molecular data from our group¹ and others, including the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network,² support the concept of 2 divergent etiologies in IC/BPS: a bladder disease characterized by an abnormal bladder urothelium, higher scores on validated pain and symptom questionnaires, and a diminishing anesthetic bladder capacity vs a non–bladder-centric systemic pain disorder comprised of interrelated comorbid urologic and non urologic symptoms and syndromes. IC/BPS wasclassified as classic (ie, Hunner lesion [HL] present or Hunner-type IC [HIC]) and everyone else (ie, HL absent or non-HIC [NHIC]). This distinction was based solely on cystoscopic findings and still persists in the current literature.

More recently, within the bladder-centric phenotype, there is an important new subgroup in addition to HIC that is comprised of patients with bladder-centric NHIC disease. The MAPP Research Network has suggested the separation of lower urinary tract symptoms (LUTS) and pain to assess outcomes of intervention.

The guidelines of the American Urological Association,³ the International Society for the Study of Bladder Pain Syndrome,⁴ and the Global Interstitial Cystitis Bladder Pain Society⁵ differ on the duration of symptoms before the symptom complex could be described as IC/BPS. Consensus thus far is an individual effort.^6,7 A global consensus on standardization of terminology, separation of LUTS vs pain for outcome, HL positivity and negativity, markers for disease, and the role of new interventions for local vs systemic therapy is needed.

REFERENCES

1. Badlani GH. Re: clinically important differences for pain and urinary symptoms in urological chronic pelvic pain syndrome: a MAPP Network study. Eur Urol. 2024;S0302-2838(24)02342-X. doi:10.1016/j.eururo.2024.04.019

2. Stephens-Shields AJ, Lai HH, Landis JR, et al. Clinically important differences for pain and urinary symptoms in urological chronic pelvic pain syndrome: a MAPP Network study. J Urol. 2023;209(6):1132-1140. doi:10.1097/JU.0000000000003394

3. Hanno PM, Erickson D, Moldwin R, Faraday MM; American Urological Association. Diagnosis and treatment of interstitial cystitis/bladder pain syndrome: AUA guideline amendment. J Urol. 2015;193(5):1545-1553. doi:10.1016/j.juro.2015.01.086

4. Proaño A, Garde G, Garrido G, Mazza O. ESSIC criteria for the diagnosis of bladder pain syndrome/interstitial cystitis (BPS/IC) and comparison with the NIDDK criteria. Arch Esp Urol. 2013;66(2):206-214.

5. Rahnama’i MS, Javan A, Vyas N, et al. Bladder pain syndrome and interstitial cystitis beyond horizon: reports from the Global Interstitial Cystitis/Bladder Pain Society (GIBS) Meeting 2019 Mumbai - India. Anesth Pain Med. 2020;10(3):e101848. doi:10.5812/aapm.101848

6. Taneja R, Pandey S, Priyadarshi S, et al. Diagnostic and therapeutic cystoscopy in bladder pain syndrome/interstitial cystitis: systematic review of literature and consensus on methodology. Int Urogynecol J. 2023;34(6):1165-1173. doi:10.1007/s00192-023-05449-w

7. Homma Y, Akiyama Y, Kim JH, et al. Definition change and update of clinical guidelines for interstitial cystitis and bladder pain syndrome. Low Urin Tract Symptoms. 202;16(5):e12532. doi:10.1111/luts.12532