Failure of bethanechol denervation supersensitivity as a diagnostic aid

Area of Science:

• Urology
• Neurology
• Diagnostic Testing

Background:

• Detrusor areflexia during cystometry suggests potential bladder dysfunction.
• Accurate diagnosis of neurogenic bladder is crucial for appropriate patient management.
• The bethanechol denervation supersensitivity test is used to evaluate bladder function.

Purpose of the Study:

• To evaluate the diagnostic accuracy of the bethanechol denervation supersensitivity test.
• To determine the rates of false positives and false negatives for this test in patients with detrusor areflexia.

Main Methods:

• 33 patients with detrusor areflexia underwent cystometry.
• A complete neurologic evaluation was performed for each patient.
• The bethanechol denervation supersensitivity test was administered.

Main Results:

• The test yielded a 24% falsely negative rate in patients with neurogenic bladder (n=21).
• The test yielded a 50% falsely positive rate in patients without neurogenic bladder (n=12).

Conclusions:

• A positive bethanechol test does not confirm neurogenic bladder.
• A negative bethanechol test does not rule out neurogenic bladder.
• The test has limited diagnostic value for neurogenic bladder.