Very high rate of false positive biochemical results when screening for pheochromocytoma in a large, undifferentiated population with variable indications for testing.
Adrenal mass
Endocrine hypertension
Metanephrine
Normetanephrine
Pheochromocytoma
Journal
Clinical biochemistry
ISSN: 1873-2933
Titre abrégé: Clin Biochem
Pays: United States
ID NLM: 0133660
Informations de publication
Date de publication:
Mar 2020
Mar 2020
Historique:
received:
06
11
2019
revised:
13
01
2020
accepted:
16
01
2020
pubmed:
25
1
2020
medline:
3
4
2020
entrez:
25
1
2020
Statut:
ppublish
Résumé
Pheochromocytoma/Paraganglioma (PPGL) is a rare tumor with non-specific presentations overlapping common entities like anxiety, hypertension, acute illness and episodic "spells." Assessment of urine normetanephrine or metanephrine (UNM-UMN) in real-life, where PPGL is very rare and PPGL mimics extremely common, may show overlap in results with loss of specificity depending on the reference range. We determined the extent to which UNM-UMN are high in people undergoing screening for PPGL. Retrospective review of all UNM-UMN performed in a central lab serving Southern Alberta over 8 years. After excluding pediatric ages and patients with CKD, there were 12,572 unique patients with 14,383 measures of UNM-UMN. 85 patients (0.7%) had markedly high UNM-UMN compatible with likely PPGL. Depending on the age category (in decades), 10-22% of all UNM results were above the upper reference limit(URL), particularly between ages of 40-60. Less than 3% had elevations in both UNM and UMN. Of those with high UNM, 99% were less than 3-fold the URL. Based on the population data, a potential new reference range for UNM is suggested, which may be more appropriate to the types of patient who undergo this form of testing. There is an extraordinarily high prevalence of high UNM seen in real-life use of the test. However, the vast majority of high UNM are unlikely to be PPGL given the disease rarity and the massive number of tests ordered. This suggests the current laboratory URL may be too low (poor specificity) and/or the reference range may not be appropriate to the type of patient being screened for PPGL. Depending on the frequency of use of any screening test in a population, if the disease is rare and the specificity of the test is poor, a high rate of false positive results will be expected.
Identifiants
pubmed: 31978379
pii: S0009-9120(19)31196-8
doi: 10.1016/j.clinbiochem.2020.01.005
pii:
doi:
Substances chimiques
Metanephrine
5001-33-2
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
26-31Informations de copyright
Copyright © 2020 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.