Case Report
Volume: 7 | Issue: 1 | Published: Jan 01, 2023 | Pages: 23 - 26 | DOI: 10.24911/ejmcr/173-1664566907
Falsely elevated levels of 25(OH) vitamin D measured on alinity: two case reports
Authors:
Mae Jeraldine de Vera
, Ann Sierens
, Leen Vandevenne
Article Info
Authors
Mae Jeraldine de Vera
Laboratory Clinical Biology Algemeen Ziekenhuis Sint-Maarten, Liersesteenweg, Mechelen, Belgium
Ann Sierens
Laboratory Clinical Biology Algemeen Ziekenhuis Sint-Maarten, Liersesteenweg, Mechelen, Belgium
Leen Vandevenne
Laboratory Clinical Biology Algemeen Ziekenhuis Sint-Maarten, Liersesteenweg, Mechelen, Belgium.
Publication History
Received: October 02, 2022
Revised: November 21, 2022
Accepted: November 21, 2022
Published: January 01, 2023
Abstract
Background: Conventional biochemistry parameters employ the use of photometry and enzymatic reactions which reduce the possibility of analytical errors. On contrary, tests performed with immunoassay are known to be more prone to analytical interferences and may subsequently yield incorrect values. Case presentation: We present two cases investigated due to very high levels of vitamin D in the serum that exceeded the measurable limit of the analyzer. Protein electrophoresis showed a monoclonal peak, revealing elevated immunoglobulin G and elevated immunoglobulin M respectively. Gold standard analysis of vitamin D using liquid chromatography-mass spectrometry revealed normal vitamin D concentrations in both cases. Further, bone marrow puncture revealed a diagnosis consistent with multiple myeloma and Waldenstroms macroglobulinemia. Conclusion: Falsely elevated levels of vitamin D exceeding the maximum measurable limit is highly suspicious. Although analytical interference in immunoassay is limited, we should keep in mind that results obtained by this method are more prone to analytical errors.
Keywords: immunoassay interference, 25(OH) vitamin D, falsely elevated, paraprotein, case report, green
