Random ‘spot’ urinary metanephrines compared with 24-h-urinary and plasma results in phaeochromocytomas and paragangliomas
Background: In patients with phaeochromocytomas or paragangliomas (PPGLs), 24-h urine collections for metanephrines (uMNs) are cumbersome. Objective: To evaluate the diagnostic utility of ratios to creatinine of ‘spot’ uMNs. Methods: Concentrations of uMNs and plasma metanephrines (pMNs) were measured by HPLC-mass-spectrometry. We retrospectively compared correlations of 24-h-urine output and ratio to creatinine in historical specimens and prospectively assessed 24-h and contemporaneous spot urines and, where possible, pMNs.