EXCRETION OF 3-METHOXY-4-HYDROXY-MANDELIC ACID AND CATECHOLAMINES IN PATIENTS WITH PHEOCHROMOCYTOMA

Abstract
Comparison of urinary catecholamine and 3-methoxy-4-hydroxymandelic acid (MHMA) excretions in established and suspected cases of pheochromocytoma demonstrated the confirmatory role of the MHMA test in diagnosis, and showed that in rare instances the excretion of MHMA may be elevated in association with an apparently normal output of catecholamines. A modification of published procedures for the estimation of urinary MHMA was employed. This method is suitable for multiple samples and is highly specific for MHMA. The adult normal range of excretion by this procedure was found to be 1.4 to 4.7 mg. per twenty-four hours.