Failure of bethanechol denervation supersensitivity as a diagnostic aid

A total of 33 patients who demonstrated detrusor areflexia during cystometry underwent the bethanechol denervation supersensitivity test. In each instance the presence or absence of a neurologic lesion was documented carefully by complete neurologic evaluation. Of the 21 patients with a neurogenic bladder there was a falsely negative rate of 24 per cent. Of the 12 patients without a neurogenic bladder the falsely positive rate was 50 per cent. It is concluded that a positive bethanechol test is not by itself indicative of neurogenic bladder nor does a negative test exclude this diagnosis.