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CASE REPORT Presented by:Yashveer Anand Rughoobur Roll number:107
CASE PRESENTATIONA 10 day old boy was admitted with new onset convulsions. In theprevious 6 days, his parents had noted left sided arm and leg twitching,right sided head turning and lips smacking.
These episodes lasted for approximately 30secs and theirfrequency had increased to seven times per hour beforeadmission.There was no history of fever, trauma, sick contacts or neonatalsepsis risk factors. The baby was breastfed and supplementedwith formula feed .
The pregnancy was unremarkable and the baby was born atterm by an uncomplicated caesarian section because of aprevious caesarian section. His birth weight was 4.1kg. On admission seizures as described were witnessed. He wasafebrile with normal vital signs. He had no dismorphicfeatures and thus physical examination was otherwiseunremarkable
Blood Biochemistry 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.
Maternal investigations demonstrated normal calcium level of 2.27mmol/L (Normal 2.19-2.60 mmol/L). 25-OH Vit D was low.The diagnosis was further revealed after further maternal history. Themother was noted to have a diet low in calcium and she reported nottaking any antenatal vitamin supplement. She also reported alwayswearing sunscreen when outdoor. The baby had not been started onvitamin D supplements.
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 forestimation.
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 lactation lack 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