Risk of Bladder, Kidney Stone Disease Higher in Patients with Multiple Sclerosis

Patients with multiple sclerosis (MS) have an increased risk of developing bladder or kidney stones compared with individuals who do not have the disease.

Prior research has characterized stone formation in patients with spinal cord injury, and although MS patients also risk developing stone disease, little research has been done.

In a study published in BJU International, investigators sought to evaluate stone composition, as well as serum and urine biochemistries in patients with MS, and to examine whether mobility and bladder management strategies are risk factors in stone formation in patients with MS.

The investigators analyzed medical records of 587 patients with both MS and kidney stone disease between 2001 and 2016, as well as the controls. Data included stone compositions, blood analysis, medication, history of stone surgeries, mobility, results of 24-hour urine biochemistry studies, and method of bladder emptying.

After analyzing stone composition, the investigators found that patients with MS were significantly more likely to have calcium phosphate stones compared with the controls (42% versus 15%, respectively), as well as struvite stones (8% versus 3%, respectively). They were less likely to have calcium oxalate monohydrate stones (39% versus 64%, respectively).

Compared with the controls, patients with MS were more likely to have had percutaneous nephrolithotomy (PCNL 25% versus 12%) or a cystolithopaxy (16% versus 3%).

Of the patients, 61 had completed a 24-hour urinary stone panel. No differences were observed between groups in urinary parameters, including urinary pH, volume, calcium, citrate, creatinine, oxalate, sodium, and uric acid.

Most notably, the method of bladder emptying was associated with stone disease. Patients who used intermittent straight catheterization (ISC) were 3.5 times more likely to get stone disease. Patients who used an indwelling catheter were nearly 10 times more likely to develop the disease.

No association was found between mobility level and stone disease, according to the study.

“Similar to findings seen in patients with spinal cord injuries, patients with MS have a high incidence of calcium phosphate stones and struvite stones when compared with matched controls,” the authors wrote. “Additionally, they were more likely to undergo PCNL. The method of bladder management appears to be a risk factor in the development of stone disease.

“These findings suggest the importance of prompt treatment of urinary tract infections in this population and delay the use of ISC, suprapubic tube, or an indwelling Foley [catheter], when possible.”