Biochemical Diagnosis of Pheochromocytoma—Is it Time to Switch to Plasma-Free Metanephrines?

Plasma Metanephrines in the Diagnosis of Pheochromocytoma

Plasma metanephrines in the diagnosis of pheochromocytoma.

OBJECTIVE To examine whether tests for plasma metanephrines, the o-methylated metabolites of catecholamines, offer advantages for diagnosis of a pheochromocytoma over standard tests for plasma catecholamines or urinary metanephrines. DESIGN Cross-sectional study. SETTING 3 clinical specialist centers. PATIENTS 52 patients with a pheochromocytoma; 67 normotensive persons and 51 patients wi...

Choice of biochemical test for diagnosis of pheochromocytoma: validation of plasma metanephrines.

Pheochromocytomas, although a rare cause of hypertension, are dangerous tumors that require consideration among large numbers of patients. The subsequent low prevalence of the tumor among those tested and inadequacies of commonly used biochemical tests make excluding or confirming the tumor an often difficult and time consuming task. Recognition that catecholamines are metabolized to free metan...

Plasma Free Metanephrines as Diagnostic Markers of Pheochromocytoma

Quantitative determination of catecholamines and their O-methyl metabolites plays an important role in the diagnosis of pheochromocytoma (PHEO) – adrenal medulla tumour. This kind of tumour synthesizes, stocks, metabolizes and mostly secretes catecholamines. For this reason it is possible to use elevated concentrations of catecholamines and their metabolic products from plasma and urine as diag...

Evaluation of an enzyme immunoassay for plasma-free metanephrines in the diagnosis of catecholamine-secreting tumors.

OBJECTIVE To define the test characteristics of an enzyme immunoassay (EIA) for plasma-free metanephrines (metanephrine and normetanephrine) in the diagnosis of pheochromocytoma and paraganglioma. DESIGN Prospective observational design from a single University Hospital. Twenty-four hour urine for catecholamines and plasma for free metanephrines were collected from patients with a clinical su...