Does serum magnesium analysis need to be a part of routine dyselectrolytemia investigation?

Abstract

Introduction: The fourth most abundant cation in the body and the second most prevalent intracellular cation, magnesium (Mg) is a co-factor for over 300 enzymes. Though magnesium abnormalities frequently accompany other electrolytes abnormalities, during electrolyte investigation, magnesium estimation is often overlooked. This study aims to investigate the occurrence of magnesium abnormalities in serum samples sent, for routine electrolyte measurement like sodium, potassium, calcium and phosphorus, to the biochemistry laboratory of Tribhuvan University teaching hospital.

Methods: Serum magnesium measurement was done in 799 serum samples ordered for various electrolyte estimation. Magnesium, Calcium and phosphorus present in sample was analyzed by BT 3500 machine spectrophotometrically. Sodium and potassium ions were analyzed by direct ion selective electrode method.

Results: Only 14(1.75%) samples were requested by physician for magnesium estimation out of total 799 samples sent for various electrolyte estimation. When all 799 samples were analyzed for magnesium level, magnesium abnormalities were identified in 76(9.5%), out of which hypermagnesemia was found in 22 (2.75%) and hypomagnesemia in 54 (6.76%) samples.

Conclusion: Since, significant numbers of patient's serum sample, sent for estimation of various electrolytes, are found to have magnesium abnormalities, we recommend routine measurement of this analyte along with other electrolytes.