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CASE REPORT

Presented by:Yashveer Anand Rughoobur

Roll number:107

A 10 day old boy was admitted with new onset convulsions. In the previous 6 days, his parents had noted left sided arm and leg twitching, right sided head turning and lips smacking.

CASE PRESENTATION

These episodes lasted for approximately 30secs and their frequency had increased to seven times per hour before admission.

There was no history of fever, trauma, sick contacts or neonatal sepsis risk factors. The baby was breastfed and supplemented with formula

feed.

The pregnancy was unremarkable and the baby was born at term by an uncomplicated caesarian section because of a previous caesarian section. His birth weight was 4.1kg. On admission seizures as described were witnessed. He was afebrile with normal vital signs. He had no dismorphic features and thus physical examination was otherwise unremarkable

Initial blood biochemistry showed normal renal function and electrolytes

but with hypocalcemia.

Total calcium - 1.80 mmol/L (Normal 1.96mmol/L- 2.66 mmol/L) and

ionized calcium - 0.82 mmol/L (normal 1.62 mmol/L – 3.10mmol/L).

His blood glucose level was within normal limits at 4.3 mmol/L.

There was low 25-OH vit D level 13mmol/L ( Normal 27-110mmol/L),

with a normal 1,25 hydroxy vit D urinary calcium, Head ultrasound was

normal and there was no clinical or radiological evidence of Rickets.

Blood Biochemistry

Maternal investigations demonstrated normal calcium level of 2.27 mmol/L (Normal 2.19-2.60 mmol/L). 25-OH Vit D was low.

The diagnosis was further revealed after further maternal history. The mother was noted to have a diet low in calcium and she reported not taking any antenatal vitamin supplement. She also reported always wearing sunscreen when outdoor. The baby had not been started on vitamin D supplements.

CASE DISCUSSION

QUESTION?

What is the cause of Hypocalcemia in this baby?

HYPOCALCEMIA

Definition: serum total concentration of <8mg/dL (2mmol/L) in terms of infants or

<7mg/dL(<1.75mmol/L) in preterm infants.

It is also defined as an ionized calcium level of <3.0 to 4.4 mg/dL (0.75- 1.10mmol/L) depending upon the method used for estimation.

CAUSES

• Infant with severe symptomatic hypocalcaemia due to maternal hypovitaminosis D.

• Mother is reported to have been wearing sunscreen outdoor.

How did the mother get hypovitaminosis D??

• Sunscreen with a sun protection factor of 8 reduces cutaneous production of vitamin D by 98%.

• So she did not supplement with vitamin D during pregnancy.

TESTS

• 25-OH and 1,25 –OH vit D levels, • serum and urinary calcium level,

• PTH level ,• Renal function tests.

RESULTS

• Low 25-OH vit D level in the baby indicates that vit D stores are low.

• Note: Normal 1,25 hydroxy vitamin D confirms that the child is able to convert vit D to its active form.

• The child’s parathyroid hormone was appropriately elevated.

SIGNS OF HYPOCALCEMIA

• Hypotonia

• Apnea

• Tetany.

RISK FACTORS OF NEONATAL HYPOCALCEMIA

Symptomatic hypocalcemia without evidence of rickets may present in the early neonatal period.

Risk factors of neonatal vit D deficiency secondary to maternal hypovitaminosis D include:

having a mother with dark skin, being born in winter months,living at extreme latitude, maternal diet low in vit D during pregnancy and lactationlack of maternal sun exposure.

CLINICAL MANIFESTATIONS OF NEONATAL HYPOCALCEMIA

• Jitteriness• Muscle jerking• Generalized or focal seizures• Stridor ( secondary to laryngospasm)• Wheezing( secondary to bronchospasm)• Vomiting (secondary to pylorospasm)

CLINICAL MANIFESTATIONS OF NEONATAL HYPOCALCEMIA

TREATMENT

• Treatment is I/V or oral calcium supplementation. The baby was managed with an I/V calcium gluconate infusion , oral calcium ,vitamin D (calcitriol) supplementation.

• The seizures resolved within 48 hours of admission

PREVENTION• Vitamin D deficiency

in infants and mothers is a public health issue.

• There is no current consensus for maternal vitamin D requirement, however 400IU/day is recommended for a pregnant woman to have a healthy child.

References

• Class Notes• Biochemistry for medics

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