Neonatal hypocalcaemia

Description

Hypocalcaemia is a common metabolic problem in newborns. In the neonate, hypocalcaemia is defined by birth weight (BW) categories. In infants with BW greater than 1500 g, hypocalcaemia is defined as a total serum calcium (Ca) concentration less than 8 mg/dL (2 mmol/L) or an ionized fraction of less than 4.4 mg/dL (1.1 mmol/L). In very low birth weight premature infants (BW<1500 g), hypocalcaemia is defined as a total serum Ca concentration less than 7 mg/dL (1.75 mmol/L) or an ionized fraction of less than 4 mg/dL (1 mmol/L). Aetiologies of early hypocalcaemia (occurs in the first two to three days after birth) include prematurity, maternal diabetes, birth asphyxia, and intrauterine growth. Causes of late hypocalcaemia (usually occurs at the end of the first week of life) include hypoparathyroidism and high phosphate intake. Most infants with hypocalcaemia are asymptomatic. If symptomatic, neuromuscular irritability is the most common sign with jitteriness and muscle jerking. Less common findings include seizures, and rarely laryngospasm, wheezing, or vomiting.

Coding note from above levels

Conditions arising in the perinatal period, even though death or morbidity occurs later, should, as far as possible, be coded to chapter 19, which takes precedence over chapters containing codes for diseases by their anatomical site. For children less than 28 days old, assume that a reported condition developed in the perinatal period, unless the duration is stated and the onset was after the first completed week of life.

Excludes

• KB64 – Transitory neonatal hypoparathyroidism

Exclusions from above levels

• 01 – Certain infectious or parasitic diseases - acquired after birth
• 02 – Neoplasms
• 05 – Endocrine, nutritional or metabolic diseases