| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Articles |
1
Laboratory of Clinical Biochemistry, Haukeland University Hospital, N-5021 Bergen, Norway, and Division for General Practice, University of Bergen, Norway.
2
Department of Pharmacology, University of Bergen,
Armauer Hansens Hus, N-5021 Bergen, Norway.
3
Fürst Medical Laboratory, Soeren Bulls vei 25,
N-1051 Oslo 10, Norway.
a Author for correspondence. Fax 0047 55 97 3115; e-mail sverre.sandberg{at}haukeland.no.
Diagnosing cobalamin deficiency is often difficult. We investigated the diagnostic strategies that 224 general practitioners used to assess cobalamin status and the criteria on which they based their decisions to supplement patients. From all serum cobalamin analyses carried out at a single laboratory during 1993, individuals with serum cobalamin concentrations <300 pmol/L were identified, and one patient per general practitioner was included. When serum methylmalonic acid (s-MMA) values >0.376 µmol/L were used as the "reference standard" for cobalamin deficiency, the serum cobalamin assay had a diagnostic sensitivity of 0.40 and a specificity of 0.98. With the same reference standard, the diagnostic accuracy of the physicians' decision to supplement patients had the same specificity but a higher sensitivity (0.51). Cost-benefit analysis indicated that measurement of s-MMA can be recommended in patients with serum cobalamin >60–90 pmol/L and <200–220 pmol/L, depending on its diagnostic accuracy.
The following articles in journals at HighWire Press have cited this article:
|
|
 |
|
  H.-A. Lakso, P. Appelblad, and J. Schneede Quantification of Methylmalonic Acid in Human Plasma with Hydrophilic Interaction Liquid Chromatography Separation and Mass Spectrometric Detection Clin. Chem., December 1, 2008; 54(12): 2028 - 2035. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Schmedes and I. Brandslund Analysis of methylmalonic Acid in plasma by liquid chromatography-tandem mass spectrometry. Clin. Chem., April 1, 2006; 52(4): 754 - 757. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. M. Gilfix Vitamin B12 and homocysteine Can. Med. Assoc. J., November 22, 2005; 173(11): 1360 - 1360. [Full Text] [PDF]
|
|
|
|
 |
|
 L. R. Solomon Cobalamin-responsive disorders in the ambulatory care setting: unreliability of cobalamin, methylmalonic acid, and homocysteine testing Blood, February 1, 2005; 105(3): 978 - 985. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Refsum, A. D. Smith, P. M. Ueland, E. Nexo, R. Clarke, J. McPartlin, C. Johnston, F. Engbaek, J. Schneede, C. McPartlin, et al. Facts and Recommendations about Total Homocysteine Determinations: An Expert Opinion Clin. Chem., January 1, 2004; 50(1): 3 - 32. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J.G. Ray and H.J. Blom Vitamin B12 insufficiency and the risk of fetal neural tube defects QJM, April 1, 2003; 96(4): 289 - 295. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. S. Morris, P. F. Jacques, I. H. Rosenberg, and J. Selhub Elevated Serum Methylmalonic Acid Concentrations Are Common among Elderly Americans , J. Nutr., September 1, 2002; 132(9): 2799 - 2803. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Matern and M. J. Magera Mass Spectrometry Methods for Metabolic and Health Assessment J. Nutr., May 1, 2001; 131(5): 1615S - 1620. [Abstract] [Full Text]
|
|
|
|
|
|
B. J. Bolann, J. D. Solli, J. Schneede, K. A. Grottum, A. Loraas, M. Stokkeland, A. Stallemo, A. Schjoth, R. B. Bie, H. Refsum, et al. Evaluation of Indicators of Cobalamin Deficiency Defined as Cobalamin-induced Reduction in Increased Serum Methylmalonic Acid Clin. Chem., November 1, 2000; 46(11): 1744 - 1750. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. J. Magera, J. K. Helgeson, D. Matern, and P. Rinaldo Methylmalonic Acid Measured in Plasma and Urine by Stable-Isotope Dilution and Electrospray Tandem Mass Spectrometry Clin. Chem., November 1, 2000; 46(11): 1804 - 1810. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. G. Klee Cobalamin and Folate Evaluation: Measurement of Methylmalonic Acid and Homocysteine vs Vitamin B12 and Folate Clin. Chem., August 1, 2000; 46(8): 1277 - 1283. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. M. Pfeiffer, S. J. Smith, D. T. Miller, and E. W. Gunter Comparison of Serum and Plasma Methylmalonic Acid Measurements in 13 Laboratories: An International Study Clin. Chem., December 1, 1999; 45(12): 2236 - 2242. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
