To Pee or Not to Pee? The Utilization of Bladder Scans in Multiple Sclerosis

Background: Bladder dysfunction is common in multiple sclerosis and can be asymptomatic. Detrusor overactivity and dyssynergia lead to urinary frequency, urgency, incontinence, and incomplete bladder emptying, which increases the risk of recurrent urinary tract infections, hydropnephrosis, and renal dysfunction. With early detection bladder dysfunction can be treated medically, reducing morbidity and improving quality of life. Measurement of PVR (post-void residual) can be a valuable tool in optimizing the treatment plan in both symptomatic and asymptomatic patients. 

Objectives: We studied the correlation between PVR, frequency of UTI, use of anti-cholinergic medications, and the presence of spinal cord involvement in MS patients with and without urinary symptoms. 

Methods: We prospectively studied 101 consecutive patients in a MS clinic during their routine neurological visit for a 3 month interval.  Each patient was given the Urogenital Distress Inventory (UDI), Incontinence Impact Questionnaire (IIQ), and additional questions regarding UTI history and management.  A patient was considered asymptomatic if he scored a zero or one on the UDI and IIQ. PVR was obtained using a Bladder Scan BVI3000.  PVR below 49 mL was considered normal, and PVR of 50 mL or more was abnormal.  A urine analysis and culture was performed on all patients, and those with abnormal PVR were further screened with a renal ultrasound and BUN /creatinine levels.  Patients were excluded if they had an indwelling catheter or were unable to transfer to the examining table.

Results: We studied 101 patients, 70 with RRMS and 31 with SPMS. 90% were female and 10% were male with a mean age of 51. 20% had PVR, and 50% of those had UTIs. In those without PVR, only 26% had UTIs.

In the RRMS group, 20 patients were asymptomatic, 3 of which had PVR. Of those, 2 had a history of UTI during the past year. In the SPMS group only one patient was asymptomatic, and she had a history of both PVR and UTI. Of the 30 symptomatic SPMS patients 11 (37%) had PVR and 4 (36%) had UTI. In the 19 patients without PVR 6 (32%) had UTI. 

Conclusions: Measurement of PVR is a valuable tool for detection of urinary retention, especially in asymptomatic patients, as occult retention may occur in a small but meaningful percentage of patients with RRMS. We found a high correlation between urinary symptoms, UTI, and PVR in our SPMS population. In RRMS, there was little correlation between the presence of symptoms and PVR.