Results of screening for phaeochromocytoma in 17 hypertensive patients with episodic symptoms

Detailed investigation of 17 patients with features suggesting paroxysmal hypertension revealed the presence of phaeochromocytoma in only 3 cases, in 2 of which the tumors were bilateral. Tumor bearing sites were localized accurately by arteriography in one patient, and by measurements of plasma catecholamines in the inferior vena cava in the other two. The effects of glucagon and phentolamine on blood pressure correlated poorly with the diagnosis. Pasma catecholamines increased after glucagon administration in the two patients with phaeochromocytoma who were tested, including one with no pressor response, and in two of the remainder. The findings show the glucagon test, with or without measurements of plasma catecholamines, to be of limited use in the diagnosis of phaeochromocytoma, while the phentolamine test had no value in this study. The key to the diagnosis was the measurement of urinary and plasma catecholamines and of urinary vanilmandelic acid.