What are the current management strategies for acute interstitial cystitis?

Management of Acute Interstitial Cystitis

Critical Clarification: Terminology and Approach

The term "acute interstitial cystitis" requires clarification, as interstitial cystitis/bladder pain syndrome (IC/BPS) is fundamentally a chronic condition, not an acute infectious process. If you are referring to an acute flare of IC/BPS, the management differs substantially from acute bacterial cystitis 1.

Management Strategy for IC/BPS (Chronic Condition)

First-Line Conservative Treatments (Should Be Initiated in All Patients)

All patients with IC/BPS should begin with behavioral modifications and multimodal pain management before escalating to pharmacologic interventions 1.

• Dietary modifications: Eliminate common bladder irritants including coffee, citrus products, and acidic foods; consider an elimination diet to identify individual triggers 1
• Fluid management: Adjust concentration and volume of urine through strategic hydration patterns 1
• Pain management: Initiate pharmacological approaches combined with stress management techniques 1
• Physical interventions: Apply local heat or cold over the bladder or perineum; address pelvic floor muscle tension 1

Second-Line Oral Pharmacotherapy (When Conservative Measures Are Insufficient)

Select one of the following oral agents based on patient comorbidities and side effect profile 1:

• Amitriptyline: Tricyclic antidepressant with neuromodulatory effects 1, 2
• Hydroxyzine: Antihistamine targeting mast cell involvement 1, 2
• Pentosan polysulfate sodium (PPS): The only FDA-approved oral therapy for IC/BPS 3, though recent evidence of pigmented maculopathy with chronic use is very concerning and must be discussed with patients before initiation 2
• Cimetidine: H2-receptor antagonist 1

Second-Line Intravesical Therapy

Dimethyl sulfoxide (DMSO) is the only FDA-approved intravesical therapy for IC/BPS 3, 4:

• Dosing: Instill 50 mL of RIMSO-50® (50% DMSO solution) directly into the bladder via catheter 4
• Retention time: Allow to remain for 15 minutes, then expel by spontaneous voiding 4
• Frequency: Repeat every two weeks until maximum symptomatic relief is obtained, then increase intervals appropriately 4
• Pre-medication: Consider oral analgesics or belladonna/opium suppositories prior to instillation to reduce bladder spasm 4
• Anesthesia consideration: In patients with severe IC/BPS and very sensitive bladders, perform initial 2-3 treatments under anesthesia (saddle block suggested) 4
• Patient counseling: Warn about garlic-like taste within minutes lasting several hours, and odor on breath/skin lasting up to 72 hours 4

Alternative intravesical options (not FDA-approved but used in practice):

• Heparin 1, 5
• Lidocaine 1

Third-Line and Beyond

• Cystoscopy with hydrodistension: Can provide both diagnostic and therapeutic benefit 1, 6
• Fulguration of Hunner's lesions: If present on cystoscopy 1
• Cyclosporine A: For refractory cases 2
• Botulinum toxin A: Intravesical injection for severe cases 6, 5

Surgical Options (Last Resort Only)

Surgical interventions should only be considered after all other treatment alternatives have been exhausted, or in the rare instance of confirmed end-stage small, fibrotic bladder 1:

• Partial cystectomy or urinary diversion procedures represent the therapeutic ultimo ratio 6
• These are appropriate only when the patient's quality of life suggests a positive risk-benefit ratio for major surgery 1

Critical Pitfalls to Avoid

• Do not treat IC/BPS with antibiotics: There is no underlying infection, and antibiotic therapy provides no therapeutic benefit 5
• Do not confuse with acute bacterial cystitis: If the patient has acute dysuria, frequency, and urgency with recent onset, consider acute bacterial cystitis (treated with nitrofurantoin, trimethoprim-sulfamethoxazole, or fosfomycin) 7
• Do not skip conservative measures: Treatment strategies must proceed using more conservative therapies first, with less conservative therapies used only if symptom control is inadequate 1
• Monitor for PPS-related eye complications: Patients on chronic pentosan polysulfate require ophthalmologic monitoring for pigmented maculopathy 2
• Do not perform routine eye exams for DMSO: While animal studies showed eye changes with large doses, routine slit lamp examinations are recommended only prior to and periodically during treatment 4