Definition:
- Hemorrhagic cystitis is inflammation of the bladder mucosa leading to hematuria, often caused by chemotherapy or radiation.
- In oncology, it is most commonly chemotherapy-induced.
Etiology in Oncology
- Chemotherapy-induced
- Cyclophosphamide → metabolite acrolein accumulates in bladder
- Ifosfamide → metabolite acrolein, higher risk than cyclophosphamide
- Radiation-induced
- Pelvic irradiation → damages bladder mucosa
- Can occur weeks to years post-radiotherapy
Pathophysiology
- Acrolein binds bladder urothelium → direct cytotoxicity
- Inflammatory cascade → hemorrhage, edema, and fibrosis
- Severity ranges from mild microscopic hematuria to severe hemorrhage with clot retention
Clinical Features
- Hematuria: microscopic → gross
- Dysuria, urgency, frequency
- Lower abdominal pain
- Rare: bladder tamponade in severe cases
Prevention & Pharmacist Role
1. Hydration
- IV fluids before, during, and after chemo to dilute urinary acrolein
2. Uroprotective Agent
- MESNA (2-mercaptoethane sulfonate sodium) binds acrolein → prevents bladder toxicity
3. Dose Adjustments
- Consider fractionated or reduced doses in high-risk patients
Treatment / Supportive Care
- Mild HC: supportive care, hydration, analgesics
- Moderate-Severe HC:
- Continuous bladder irrigation (for clot retention)
- Pain control
- Intravesical therapy (e.g., alum, formalin) in refractory cases
- Severe cases: urology consult for cystoscopy or surgical intervention
High-Yield Pharmacist Pearls
- Cyclophosphamide & ifosfamide → classic chemo agents causing HC
- MESNA + hydration is standard prophylaxis
- Monitor for hematuria, dysuria, urinary frequency during and after therapy
- Pediatric patients are at higher risk due to higher metabolite exposure per BSA