These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Comparison of plasma metanephrines measured by a commercial immunoassay and urinary catecholamines in the diagnosis of pheochromocytoma.
    Author: Christensen TT, Frystyk J, Poulsen PL.
    Journal: Scand J Clin Lab Invest; 2011 Dec; 71(8):695-700. PubMed ID: 22023043.
    Abstract:
    BACKGROUND: The diagnosis of pheochromocytomas requires consideration among patients suffering from hypertension, unexplained spells, incidental adrenal masses, or a family history of pheochromocytoma. Accordingly, the diagnosis requires a biochemical test with high sensitivity and specificity. AIM: To compare plasma free metanephrines as measured by a commercial immunoassay and the 24-hour urinary excretion of catecholamines. METHOD: Plasma free metanephrines were measured in 185 patients suspected of pheochromocytoma. Concomitant measurements of urinary catecholamines were performed in 115 patients. Based on clinical findings, imaging and biochemistry 11 cases were found; 9 were diagnosed with pheochromocytoma, one patient with paraganglioma and one patient with ganglioneuroma. RESULTS: All patients with pheochromocytoma/paraganglioma had abnormally elevated concentrations of either plasma metanephrine or normetanephrine. The patient with ganglioneuroma had normal plasma metanephrine levels, corresponding to a sensitivity of 91%. In two patients where pheochromocytoma was excluded, plasma metanephrin or normetanephrine was above the reference level, corresponding to a specificity of 99%. Urinary catecholamines were determined in 10 of 11 patients with a positive diagnosis, and all 10 showed elevated levels of either urinary epinephrine or norepinephrine, including the patient with ganglioneuroma (equivalent to a sensitivity of 100%). Seven patients, in whom pheochromocytoma was excluded, had elevated urinary catecholamines (equivalent to a specificity of 94%). CONCLUSION: Measurement of plasma free metanephrines by immunoassay appears to be a useful diagnostic test in patients suspected of pheochromocytoma, with a high specificity as compared with urinary catecholamines. The latter may result in fewer false-positive findings, an outcome which may be particularly troublesome.
    [Abstract] [Full Text] [Related] [New Search]