What imaging studies are recommended for patients with recurrent cystitis?

Imaging Recommendations for Recurrent Cystitis

Imaging studies are not routinely recommended for patients with uncomplicated recurrent cystitis but should be considered for complicated cases including nonresponders to therapy, frequent reinfections, or those with underlying risk factors. 1

Uncomplicated Recurrent Cystitis

• Imaging is not routinely indicated for uncomplicated recurrent cystitis due to the low yield of anatomic abnormalities, as most women have normal urinary tracts 1
• Uncomplicated recurrent UTIs are defined as three or more episodes in 12 months or two or more episodes in 6 months 2

Complicated Recurrent Cystitis: When Imaging is Indicated

Imaging should be considered in the following scenarios:

• Patients who do not respond to conventional antibiotic therapy 1
• Patients with frequent reinfections or relapses, particularly infections recurring within 2 weeks of treatment 1
• Patients with known underlying risk factors for complicated UTIs 1
• Persistent hematuria or persistent asymptomatic bacteriuria 2

Recommended Imaging Studies for Complicated Cases

First-Line Imaging

• CT Urography (CTU) is the primary recommended test for evaluation of recurrent complicated UTIs 1

  • Provides detailed anatomic depiction of the entire urinary tract (kidneys, collecting systems, ureters, and bladder)
  • Excellent for detecting congenital anomalies, obstruction, renal and urothelial lesions
  • Includes unenhanced, nephrographic phase, and excretory phase images

• Ultrasound of kidneys, bladder, and retroperitoneum 1, 2

  • Useful as an initial screening tool in complicated cases
  • Particularly valuable for detecting certain conditions
  • Recommended as initial imaging for women with recurrent UTIs to screen for underlying urinary tract abnormalities 2

Alternative/Specialized Imaging

• MR Urography (MRU) is recommended as an alternative to CTU 1, 3

  • Appropriate for patients with contraindications to CT or iodinated contrast
  • Provides more functional information than CT
  • Has supplanted intravenous urography (IVU) at most institutions

• CT Pelvis with Bladder Contrast (CT Cystography) 1

  • Specifically useful for diagnosing bladder fistulas and leaks
  • Has replaced fluoroscopic cystogram for evaluation of traumatic bladder injuries

Conditions Detectable on Imaging

• Imaging can identify causes of bacterial persistence including 1:
  • Urinary calculi
  • Foreign bodies
  • Urethral or bladder diverticula
  • Infected urachal cyst
  • Postoperative changes
  • Structural abnormalities like ureteroceles

Important Considerations and Caveats

• Historically used techniques such as intravenous urography (IVU) are no longer recommended 1
• Standard contrast-enhanced CT of the abdomen and pelvis is not optimally tailored for evaluation of the urothelium 1
• Cystoscopy may be warranted in women with recurrent UTIs, particularly those over 50 years of age, as approximately 8% may have significant abnormalities (urethral stricture, bladder calculus, bladder diverticulum, or colovesical fistula) 4
• Women without risk factors for recurrent UTI and with normal imaging may not require cystoscopy 4
• Cross-sectional imaging techniques help in early detection and management of UTIs, potentially reducing the prevalence and severity of complications 3