What is interstitial cystitis pain syndrome?

Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS)

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition characterized by an unpleasant sensation (pain, pressure, or discomfort) perceived to be related to the urinary bladder, associated with lower urinary tract symptoms lasting more than six weeks, in the absence of infection or other identifiable causes. 1

Definition and Core Characteristics

• IC/BPS is defined by symptoms lasting at least six weeks, allowing for earlier treatment initiation compared to definitions requiring longer symptom durations 1
• Pain is the hallmark symptom, typically perceived in the suprapubic region but may extend throughout the pelvis including the urethra, vulva, vagina, rectum, and to extragenital locations such as the lower abdomen and back 2
• Many patients describe their symptoms as "pressure" rather than pain, making it important to use broad descriptors when evaluating patients 2, 1
• Pain typically worsens with bladder filling and improves with urination, and may be exacerbated by specific foods or drinks 2

Associated Symptoms

• Urinary frequency is almost universal (92% of patients) but is not specific to IC/BPS 2
• Urinary urgency is extremely common (84% of patients) but differs qualitatively from overactive bladder urgency 2
• IC/BPS patients typically void to avoid or relieve pain, whereas overactive bladder patients void to avoid incontinence 2
• IC/BPS patients may experience a more constant urge to void rather than the sudden compelling urge characteristic of overactive bladder 2, 1

Pathophysiology

• The exact cause of IC/BPS remains unclear, but several mechanisms have been proposed 3:
  • Urothelial dysfunction (defects in the bladder lining) 3
  • Chronic inflammation of the bladder 3
  • Central sensitization (abnormal pain processing in the nervous system) 3
  • Possible autoimmune components 4

Clinical Subtypes

• Hunner lesion IC (HIC): Characterized by distinct inflammatory lesions visible on cystoscopy 2, 3
• Non-Hunner lesion IC (NHIC): No visible lesions on cystoscopy but symptoms persist 3
• The presence of Hunner lesions is the only consistent cystoscopic finding that leads to a specific diagnosis 2

IC/BPS in Men vs. Chronic Prostatitis

• Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) shares similar clinical characteristics with IC/BPS 2
• CP/CPPS is characterized by pain in the perineum, suprapubic region, testicles, or tip of the penis, often exacerbated by urination or ejaculation 2
• The diagnosis of IC/BPS should be strongly considered in men with pain perceived to be related to the bladder and associated with urinary frequency, nocturia, or an urgent desire to void 2
• Some men may meet criteria for both conditions, and treatment approaches can include therapies for both IC/BPS and CP/CPPS 2

Diagnostic Approach

• Diagnosis requires careful history, physical examination, and laboratory testing to document symptoms and exclude other disorders 2
• Basic laboratory testing should include urinalysis and urine culture to rule out infection 1
• Cystoscopy should be performed in patients for whom Hunner lesions are suspected, as this is the only reliable way to diagnose their presence 2, 1
• There are no agreed-upon urodynamic criteria diagnostic for IC/BPS, and urodynamics are not recommended for routine clinical use 2
• The condition is often misdiagnosed or diagnosis is delayed due to the wide spectrum of symptoms and physical exam findings 2

Treatment Approaches

• The 2022 AUA Guideline categorizes treatments into behavioral/non-pharmacologic, oral medicines, bladder instillations, procedures, and major surgery 2
• Treatment should be individualized based on the unique characteristics of each patient, particularly distinguishing between Hunner lesion and non-Hunner lesion subtypes 2, 3
• Pentosan polysulfate (Elmiron) is FDA-approved for IC/BPS and has shown efficacy in clinical trials, with 38% of patients showing >50% improvement in bladder pain compared to 18% with placebo 5

Common Pitfalls to Avoid

• Using research or clinical trial definitions (like NIDDK criteria) in clinical practice, which can lead to misdiagnosis or delays in treatment 2
• Treating with antibiotics when no infection is present, which can lead to antibiotic resistance and disruption of protective flora 1, 6
• Failing to recognize the overlap between IC/BPS and other conditions like overactive bladder or urinary tract infection, leading to misdiagnosis 7
• Neglecting to consider IC/BPS in men with pelvic pain symptoms 2
• Delaying diagnosis and treatment, which may lead to central sensitization and more difficult-to-treat chronic pain 8