Abstract

The association of hypomagnesemia with hypocalcemia is known for the past few years and in majority of these instances, disturbances of magnesium (Mg) homeostasis is secondary to an obvious cause. Primary hypomagnesemia due to disorder of magnesium metabolism though rare, has been reported. In these infants who are both hypomagnesemic and hypocalcemic, symptoms and biochemical disturbances respond only to administration of magnesium salts. Hypomagnesemia is now reported in neonates and during early infancy (3-5) as a result of specific malabsorption of magnesium.^[1]Association of hypomagnesemia with calcium deficiency is a known disorder in neonates which needs immediate attention. While most cases occur along with calcium deficiency, there are a sizeable number of cases which have primary magnesium deficiency. Symptomatic hypocalcemia unresponsive to adequate doses of IV calcium therapy is usually due to hypomagnesemia. It may present either as Early Neonatal Hypocalcemia or later as Late Neonatal Hypocalcemia.^[2] The objectives of our study were to find out the incidence of hypomagnesemia in neonatal seizures and to study its correlation with hypomagnesemia.

Methods: A arbitrary sample size of 70 was decided for this particular study based on average number of yearly admissions of neonatal seizures.For the purpose of our study, Serum Magnesium Levels below 1.6 mg/dl was considered as Hypomagnesemia and a Serum Ionic Calcium Level of less than 3.9 mg/dl was considered as Hypocalcemia.^[3] Clinical examination of all study subjects was conducted. All relevant investigations such as hemoglobin, complete blood count, random blood sugar, ultra sonogram of Skull, electroencephalogram, Serum Magnesium, Serum Calcium and cerebrospinal fluid examination  was done and duly noted.The descriptive statistics was analysed as ratios & percentages. The quantitative data was expressed as measn ± SD and chi-square test applied if applicable.

Results: Hypoxic-ischemic encephalopathy (HIE)& Meningitis were the 2 major causes of neonatal seizures in our population, which amounted to approximately 73% of cases of neonatal seizures.The important causes of electrolyte imbalances leading to neonatal seizures were Hypocalcemia (12.86%) and Hypomagnesemia (2.86%). Out of the 2 cases of Hypomagnesemia, 1 case was associated with Hypocalcemia (i.e. mixed electrolyte imbalance).

Conclusion: 50% of the neonates had no specific risk factors associated with hypocalcemia & hypomagnesemia. The important causes of electrolyte imbalances leading to neonatal seizures were Hypocalcemia (12.86%) and Hypomagnesemia (2.86%).Out of the 2 cases of Hypomagnesemia, 1 case was associated with Hypocalcemia (i.e. mixed electrolyte imbalance). The mean (±SD) levels of serum ionic calcium in our study population was 4.64 ± 0.94 mg/dl while that of serum magnesium was 1.78 ± 0.13 mg/dl. There was no evidence of a Linear Correlation between the 2 variables (p > 0.05).

Keywords: hypomagnesemia, hypocalcemia, neonatal seizures.