MS Drugs and UTI Risk: Recommendations for Management

Intermittent catheterization is the preferred bladder management method for MS patients to reduce UTI risk compared to indwelling catheters. 1

UTI Risk in MS Patients

UTIs are one of the three most common non-neurological complications in MS patients, with high prevalence, hospitalization rates, and mortality 2
MS patients are particularly susceptible to UTIs due to neurogenic lower urinary tract dysfunction (NLUTD), which commonly occurs in this population 1
Common UTI symptoms in MS patients include urinary urgency, polyuria, nocturia, urinary retention, and incontinence 2
The most common causative organisms are Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae 2, 3

There is limited specific evidence comparing UTI risk among different MS disease-modifying therapies (DMTs) 1
Some immunosuppressive treatments increase UTI risk in MS patients, particularly those causing hypogammaglobulinemia 4
Natalizumab requires enhanced pharmacovigilance, including frequent MRI scanning, due to risk of opportunistic infections 1

Clean intermittent catheterization (CIC) is strongly recommended over indwelling catheters for bladder emptying in MS patients with NLUTD 1
- CIC is associated with lower rates of UTI compared to indwelling urethral or suprapubic catheters 1
- Pooled data shows that the percentage of patients experiencing UTI during follow-up periods favors CIC over other catheterization methods 1
If chronic indwelling catheterization is necessary, suprapubic catheterization is recommended over urethral catheters 1
- Suprapubic catheters are associated with higher rates of bladder stones than CIC but have advantages over urethral catheters 1
For MS patients with storage symptoms, antimuscarinic medications or beta-3 adrenergic receptor agonists may be recommended to improve bladder parameters 1
- Mirabegron (a beta-3 agonist) has been associated with UTIs as a common adverse event, particularly in geriatric patients 5
- Regular monitoring is recommended when using these medications, especially in patients with pre-existing hypertension 5

Cranberry products are not recommended for UTI prevention in MS patients 1, 6
- Multiple randomized controlled trials have shown that cranberry does not reduce UTI rates in MS patients with urinary disorders 1, 6
Asymptomatic bacteriuria should not be screened for or treated systematically 1, 4
- Treatment of asymptomatic bacteriuria has not been shown to be effective and can create antimicrobial resistance 1
- Exceptions include pregnancy, prior to invasive urological procedures, or in patients requiring immunosuppression 4
For patients with recurrent UTIs, stabilization of the neurogenic bladder should be the primary prevention strategy 4
- In some cases, weekly oral cycling antibiotics can be proposed after specialist consultation 4

Antibiotic therapy is only indicated for symptomatic UTIs 1
Urine should be sent for microscopy, culture, and sensitivity in MS patients presenting with symptoms potentially indicating UTI 1
Indwelling catheters should be changed prior to collection of urine samples 1
Empirical therapy should be started based on suspected causative organisms' antibiotic sensitivities, then adjusted according to culture results 1

Urinary dipstick or routine microscopy/culture testing is not recommended in asymptomatic MS patients 1
Pyuria is common in catheterized patients and has no predictive value in differentiating symptomatic UTI from asymptomatic bacteriuria 1
Antibiotic resistance is more frequent in patients with multiple UTI presentations, emphasizing the importance of appropriate antibiotic selection 3
MS patients presenting to hospital for UTIs are more often male, older, with progressive MS and high levels of disability 3