Abstract
BACKGROUND: Measurements of plasma or urinary metanephrines are recommended for diagnosis of pheochromocytoma and paraganglioma (PPGL). What test offers optimal diagnostic accuracy for patients at high and low risk of disease, whether urinary free metanephrines offer advantages over deconjugated metanephrines, and what advantages are offered by including methoxytyramine in panels all remain unclear. METHODS: A population of 2056 patients with suspected PPGLs underwent prospective screening for disease using mass spectrometric-based measurements of plasma free, urinary deconjugated, and urinary free metanephrines and methoxytyramine. PPGLs were confirmed in 236 patients and were excluded in others on follow-up evaluation. RESULTS: Measurements of plasma free metabolites offered higher (P < 0.01) diagnostic sensitivity (97.9%) than urinary free (93.4%) and deconjugated (92.9%) metabolites at identical specificities for plasma and urinary free metabolites (94.2%) but at a lower (P< 0.005) specificity for deconjugated metabolites (92.1%). The addition of methoxytyramine offered little value for urinary panels but provided higher (P < 0.005) diagnostic performance for plasma measurements than either urinary panel according to areas under ROC curves (0.991 vs 0.972 and 0.964). Diagnostic performance of urinary and plasma tests was similar for patients at low risk of disease, whereas plasma measurements were superior to both urinary panels for high-risk patients. CONCLUSIONS: Diagnosis of PPGLs using plasma or urinary free metabolites provides advantages of fewer falsepositive results compared with commonly measured deconjugated metabolites. The plasma panel offers better diagnostic performance than either urinary panel for patients at high risk of disease and, with appropriate preanalytics, provides the test of choice. Measurements of methoxytyramine in urine show limited diagnostic utility compared with plasma.
| Original language | English |
|---|---|
| Journal | Clinical Chemistry |
| Volume | 64 |
| Issue number | 11 |
| Pages (from-to) | 1646-1656 |
| Number of pages | 11 |
| ISSN | 0009-9147 |
| DOIs | |
| Publication status | Published - 01.11.2018 |
Funding
Employment or Leadership: None declared. Consultant or Advisory Role: None declared. Stock Ownership: None declared. Honoraria: None declared. Research Funding: Deutsche Forschungsgemeinschaft (CRC/Transre-gio 205/1), Entity: European Union Seventh Framework Programme (FP7/2007–2013) under grant agreement 259735, European Union Horizon 2020 Program (ENS@T-HT - #633983-2), Institute of Cardiology. G. Eisenhofer, Deutsche Forschungsgemeinschaft (EI855/1/2, KFO252). Expert Testimony: None declared. Patents: G. Eisenhofer, DE 10 2014 104 167.4.
Research Areas and Centers
- Academic Focus: Center for Brain, Behavior and Metabolism (CBBM)
