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Gynaecology

Interstitial Cystitis / Bladder Pain Syndrome

High EvidenceUpdated: 2025-12-24

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Red Flags

  • Haematuria (Exclude Carcinoma in Situ / Bladder Cancer)
  • Recurrent UTIs (May Mask or Coexist)
  • Symptoms Not Responding to Initial Treatment
Overview

Interstitial Cystitis / Bladder Pain Syndrome (IC/BPS)

1. Clinical Overview

Summary

Interstitial Cystitis / Bladder Pain Syndrome (IC/BPS) is a chronic condition characterised by persistent bladder pain, urinary urgency, and frequency (symptoms ≥6 weeks) in the absence of urinary tract infection or other identifiable pathology. The pain is typically related to bladder filling and relieved by voiding. The underlying cause is thought to involve defects in the bladder urothelial glycosaminoglycan (GAG) layer, leading to increased permeability, urothelial damage, and chronic inflammation. IC/BPS predominantly affects women (9:1 ratio). Diagnosis is clinical and by exclusion. Cystoscopy may reveal Hunner's ulcers/lesions (~10%, Classic type) or glomerulations (petechial haemorrhages after hydrodistension). Management is multimodal: Lifestyle/Dietary modification, Oral therapies (Amitriptyline, Pentosan Polysulphate, Antihistamines), Intravesical instillations (DMSO, Heparin, Hyaluronic Acid), and Interventional procedures (Hydrodistension, Fulguration of Hunner's lesions). IC/BPS is a chronic, debilitating condition with significant impact on quality of life. [1,2]

Clinical Pearls

Diagnosis of Exclusion: IC/BPS is diagnosed after excluding infection, malignancy, and other causes. Sterile pyuria and negative cultures are typical.

GAG Layer Defect: The leading theory is that the protective mucus layer on the bladder lining is defective, allowing irritants in urine to damage the bladder wall.

Hunner's Lesions = Classic IC (~10%): Red, inflamed patches on cystoscopy. More severe phenotype. May respond to fulguration/injection.

"Dietary Triggers": Caffeine, Alcohol, Acidic foods, Spicy foods commonly worsen symptoms. Keep a food diary.


2. Epidemiology

Prevalence

  • Prevalence: ~0.5-1% of population (Variable estimates due to diagnostic challenges).
  • Sex: Female >> Male (9:1).
  • Age: Any age, but peak 30-50 years.

Associations

AssociationNotes
FibromyalgiaCommon overlap. Central sensitisation syndromes.
Irritable Bowel Syndrome (IBS)Common overlap.
Chronic Fatigue SyndromeAssociated.
VulvodyniaCommon in women with IC/BPS.
Depression / AnxietyHigh rates due to chronic pain and symptom burden.

3. Pathophysiology

Proposed Mechanisms

  1. GAG Layer Deficiency: Glycosaminoglycan layer normally protects urothelium. Defective layer → Urine penetrates urothelium → Activates sensory nerves → Pain.
  2. Urothelial Dysfunction / Increased Permeability: Allows potassium and other irritants to penetrate bladder wall.
  3. Neurogenic Inflammation: Mast cell activation → Release of histamine, Substance P → Inflammation and pain.
  4. Central Sensitisation: Chronic pain leads to changes in CNS pain processing.
  5. Autoimmune Component: Some evidence of autoantibodies.

Subtypes

SubtypeFeatures
Hunner's Lesion Type (Classic IC)~10%. Inflammatory patches/ulcers on cystoscopy. More severe. May benefit from fulguration.
Non-Hunner's Type (BPS)~90%. Cystoscopy may show glomerulations or be normal.

4. Differential Diagnosis
ConditionKey Features
Interstitial Cystitis / BPSChronic bladder pain, Urgency, Frequency. No infection. Symptoms >6 weeks. Diagnosis of exclusion.
Urinary Tract Infection (UTI)Positive urine culture. Responds to antibiotics.
Overactive Bladder (OAB)Urgency/Frequency but No Pain.
Bladder Cancer / Carcinoma in Situ (CIS)Haematuria, Irritative symptoms. Cystoscopy + Biopsy essential. Cytology may be positive.
Bladder StoneSuprapubic pain, Haematuria, Dysuria. Imaging positive.
Endometriosis (Bladder)Cyclical symptoms with menstruation. Haematuria during menses.
Radiation CystitisHistory of pelvic radiotherapy.
Chemical Cystitis (Cyclophosphamide)Drug history. Haemorrhagic cystitis.
Pelvic Floor DysfunctionPelvic pain, Dyspareunia. May coexist with IC/BPS.

5. Clinical Presentation

Symptoms (The Triad)

SymptomNotes
Bladder Pain / Suprapubic PainRelated to bladder filling. Relieved by voiding. May also have pelvic, urethral, or perineal pain.
Urinary FrequencyDaytime frequency (Often >8 voids/day). May void very frequently (Every 30 mins - 2 hours).
UrgencySensation of needing to void urgently. Without incontinence usually.
NocturiaWaking at night to void. Common.

Other Features

FeatureNotes
DyspareuniaPain during intercourse.
Symptom FlaresTriggered by Diet (Caffeine, Alcohol, Acidic/Spicy foods), Stress, Menstruation.
Chronic CourseWaxing and waning symptoms. Chronic condition.

6. Investigations

Purpose: Exclude Other Causes (Diagnosis of Exclusion)

InvestigationPurpose
Urinalysis + Urine CultureExclude UTI. May show sterile pyuria. Culture negative.
Urine CytologyExclude bladder cancer (CIS). Especially if haematuria or high-risk patient.
Bladder DiaryFrequency-Volume Chart. Quantifies symptom burden.
Post-Void Residual (PVR)Exclude urinary retention. Usually low in IC/BPS.
Cystoscopy (± Hydrodistension)Not mandatory for diagnosis but often performed. Excludes tumour, stone, other pathology.
Potassium Sensitivity Test (Parsons Test)Not widely used now. Positive if pain with intravesical KCl.

Cystoscopy Findings

FindingNotes
Hunner's Lesions/UlcersClassic IC (~10%). Red, inflamed patches on bladder wall. May have central scar.
GlomerulationsPetechial haemorrhages after Hydrodistension (Bladder stretched under anaesthesia). Non-specific but supportive.
Normal AppearanceDoes NOT exclude IC/BPS.

7. Management

Management Algorithm

       SUSPECTED IC/BPS
       (Bladder Pain + Urgency + Frequency ≥6 weeks, No Infection)
                     ↓
       EXCLUDE OTHER DIAGNOSES
       - Urinalysis, Urine Culture, Cytology
       - Bladder Diary
       - Consider Cystoscopy (if atypical features, haematuria, or not responding)
                     ↓
       CONFIRM IC/BPS (Clinical Diagnosis of Exclusion)
                     ↓
       FIRST-LINE: LIFESTYLE & CONSERVATIVE
    ┌──────────────────────────────────────────────────────────┐
    │  - DIET MODIFICATION: Avoid triggers (Caffeine, Alcohol, │
    │    Acidic foods, Spicy foods, Artificial sweeteners).   │
    │    Keep food diary. IC Diet resources.                   │
    │  - STRESS REDUCTION: Relaxation techniques, Mindfulness. │
    │  - BLADDER TRAINING: Gradually increase voiding intervals.│
    │  - PELVIC FLOOR PHYSIOTHERAPY: If pelvic floor dysfunction│
    │    present.                                              │
    │  - PATIENT EDUCATION: IC support groups.                 │
    └──────────────────────────────────────────────────────────┘
                     ↓
       INADEQUATE RESPONSE?
                     ↓
       SECOND-LINE: ORAL MEDICATIONS
    ┌──────────────────────────────────────────────────────────┐
    │  - AMITRIPTYLINE 10-75mg Nocte (Low-dose TCA)           │
    │    - Reduces pain, Urgency. Also helps sleep/mood.       │
    │    - Start low, Titrate slowly.                          │
    │                                                          │
    │  - PENTOSAN POLYSULPHATE SODIUM (Elmiron) 100mg TDS     │
    │    - GAG layer replacement (Oral).                       │
    │    - Takes 3-6 months for effect.                        │
    │    - Note: Associated with pigmentary maculopathy (Eye). │
    │                                                          │
    │  - HYDROXYZINE 25-50mg Nocte (Antihistamine)            │
    │    - Mast cell stabiliser.                               │
    │    - Sedating.                                           │
    │                                                          │
    │  - CIMETIDINE 200-400mg BD (H2 Blocker)                 │
    │    - Some evidence for symptom relief.                   │
    └──────────────────────────────────────────────────────────┘
                     ↓
       INADEQUATE RESPONSE?
                     ↓
       THIRD-LINE: INTRAVESICAL THERAPY
    ┌──────────────────────────────────────────────────────────┐
    │  - DMSO (Dimethyl Sulfoxide) Instillations              │
    │    - Anti-inflammatory, Analgesic.                       │
    │    - Weekly x 6 weeks, then PRN.                         │
    │                                                          │
    │  - HEPARIN +/- LIDOCAINE Instillations                  │
    │    - GAG layer replacement.                              │
    │                                                          │
    │  - HYALURONIC ACID / CHONDROITIN SULPHATE (e.g., iAluRil)│
    │    - GAG layer replacement.                              │
    │    - Weekly initially, then monthly maintenance.         │
    └──────────────────────────────────────────────────────────┘
                     ↓
       REFRACTORY CASES / HUNNER'S LESIONS?
                     ↓
       REFER TO SPECIALIST (UROLOGY/PAIN MEDICINE)
    ┌──────────────────────────────────────────────────────────┐
    │  - CYSTOSCOPY WITH HYDRODISTENSION                      │
    │    - Diagnostic + Therapeutic (Short-term relief).       │
    │                                                          │
    │  - FULGURATION / INJECTION OF HUNNER'S LESIONS          │
    │    - Laser/Electrocautery of lesions ± Steroid injection.│
    │    - Often very effective for Hunner's type.             │
    │                                                          │
    │  - BOTOX INJECTION (Intradetrusor)                      │
    │    - Off-label. May reduce urgency/pain.                 │
    │                                                          │
    │  - NEUROMODULATION (Sacral Nerve Stimulation)           │
    │    - For refractory cases.                               │
    │                                                          │
    │  - CYCLOSPORINE A (Immunosuppressant)                   │
    │    - Specialist use. Significant side effects.           │
    │                                                          │
    │  - CYSTECTOMY + URINARY DIVERSION                        │
    │    - Last resort. For truly refractory, debilitating.    │
    │    - Variable success.                                   │
    └──────────────────────────────────────────────────────────┘

Treatment Summary

LineTreatmentNotes
1stLifestyle: Diet, Stress reduction, Bladder training, Pelvic floor PTConservative first.
2ndOral: Amitriptyline, Pentosan Polysulphate, HydroxyzineSeveral months trial.
3rdIntravesical: DMSO, Heparin, Hyaluronic AcidRequires catheterisation.
4thInterventional: Hydrodistension, Hunner's fulguration, Botox, NeuromodulationSpecialist.
Last ResortCystectomyRarely needed.

8. Complications
ComplicationNotes
Reduced Quality of LifeChronic pain, Frequency, Sleep disruption. Major impact.
Depression / AnxietyHigh rates. Screen and treat.
Sexual DysfunctionDyspareunia. Relationship impact.
Small Bladder Capacity (Contracted Bladder)In severe, long-standing cases.

9. Prognosis and Outcomes
  • Chronic Condition: No cure. Symptoms often wax and wane.
  • Variable Response to Treatment: Multimodal approach usually needed.
  • Spontaneous Remission: Can occur in some patients (~10-20%).
  • Hunner's Lesion Type: May respond well to fulguration.

10. Evidence and Guidelines

Key Guidelines

GuidelineOrganisationKey Recommendations
EAU Guidelines: Chronic Pelvic PainEuropean Association of UrologyDiagnosis of exclusion. Multimodal treatment.
AUA Guidelines: IC/BPSAmerican Urological AssociationStepwise approach. Lifestyle first. Amitriptyline, Intravesicals.

11. Patient and Layperson Explanation

What is Interstitial Cystitis?

IC/BPS is a chronic condition affecting the bladder. It causes pain in the bladder area, a strong urge to urinate, and needing to pass urine very frequently. It is not caused by infection.

What causes it?

The exact cause is not fully understood, but it is thought that the protective lining of the bladder is damaged, allowing irritants in the urine to affect the bladder wall and cause pain.

How is it treated?

Treatment involves a combination of approaches:

  1. Diet changes – Avoiding foods and drinks that irritate the bladder (caffeine, alcohol, spicy foods).
  2. Medications – Tablets to reduce pain and bladder sensitivity (like low-dose Amitriptyline).
  3. Bladder instillations – Medication put directly into the bladder through a catheter.
  4. Specialist treatments – Procedures like stretching the bladder or treating ulcers.

Will it go away?

IC/BPS is usually a long-term (chronic) condition, but symptoms can come and go. With the right management, most people can achieve significant improvement in their symptoms and quality of life.


12. References

Primary Sources

  1. Hanno PM, et al. AUA guideline for the diagnosis and treatment of interstitial cystitis/bladder pain syndrome. J Urol. 2011;185(6):2162-70. PMID: 21497847.
  2. EAU Guidelines on Chronic Pelvic Pain. 2022.

13. Examination Focus

Common Exam Questions

  1. Hallmark Symptom Pattern: "What is the characteristic relationship between pain and voiding in IC/BPS?"
    • Answer: Pain related to bladder filling, relieved by voiding.
  2. Cystoscopy Finding (Classic Type): "What is seen on cystoscopy in Classic Interstitial Cystitis?"
    • Answer: Hunner's Ulcers/Lesions – Red, inflamed patches.
  3. First-Line Oral Medication: "First-line oral medication for IC/BPS?"
    • Answer: Amitriptyline (Low-dose TCA).
  4. Intravesical Therapy: "Name an intravesical agent used for IC/BPS."
    • Answer: DMSO, Heparin, Hyaluronic Acid.

Viva Points

  • Pentosan Polysulphate Eye Risk: Pigmentary maculopathy with long-term use. Ophthalmology monitoring.
  • Multimodal Approach: Emphasise that no single treatment is universally effective.

Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. Clinical decisions should account for individual patient circumstances. Always consult appropriate specialists.

Last updated: 2025-12-24

At a Glance

EvidenceHigh
Last Updated2025-12-24

Red Flags

  • Haematuria (Exclude Carcinoma in Situ / Bladder Cancer)
  • Recurrent UTIs (May Mask or Coexist)
  • Symptoms Not Responding to Initial Treatment

Clinical Pearls

  • **Diagnosis of Exclusion**: IC/BPS is diagnosed after excluding infection, malignancy, and other causes. Sterile pyuria and negative cultures are typical.
  • **GAG Layer Defect**: The leading theory is that the protective mucus layer on the bladder lining is defective, allowing irritants in urine to damage the bladder wall.
  • **Hunner's Lesions = Classic IC (~10%)**: Red, inflamed patches on cystoscopy. More severe phenotype. May respond to fulguration/injection.
  • **"Dietary Triggers"**: Caffeine, Alcohol, Acidic foods, Spicy foods commonly worsen symptoms. Keep a food diary.

Guidelines

  • NICE Guidelines
  • BTS Guidelines
  • RCUK Guidelines