International Journal of Clinical Case Reports 2017, Vol.7, No.10, 42-44
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Reassessment at the age of two years of age without any treatment found a calcium level at 9.8 mg/dl,
phosphatemia level at 6.1 mg/dl and PTH level was at 21.4 pg/ml. Vitamin D level was at 27 ng/ml.
In this case, the diagnosis of neonatal vitamin D deficiency secondary to deficiency in the mother was retained,
and what was in favor of this later diagnosis was the presence of signs of hypocalcaemia in the mother during
pregnancy and low level of 25 hydroxy vitamin D in the mother.
2 Discussion
Hypocalcemia is a frequently observed abnormality in neonates. It is defined as total serum calcium of less than 7
mg/dl (1.75 mmol/l) or ionized calcium less than 4 mg/dL (1 mmol/l) in preterm infants and less than 8 mg/dl (2
mmol/l) or ionized calcium less than 4.8 mg/dl (1.2 mmol/l) in full term neonates (Oden, 2000).
The usual causes of early onset hypocalcaemia occurring within 72 h of life are low birth weight babies, infants of
mothers with diabetes and cases of perinatal asphyxia (Venkataraman et al., 1986). Whereas the usual causes of
late onset hypocalcaemia occurring after 72 h of life include neonatal hypoparathyroidism, maternal
hyperparathyroidism, sick neonate, hypomagnesaemia and vitamin D deficiency (Venkataraman et al., 1985).
Vitamin D deficiency has been increasingly recognized as a worldwide epidemic, affecting children, adults and
the elderly alike. Vitamin D deficiency in women in the reproductive age group is also increasing due to lifestyle
factors, including increased time spent indoors both in the workplace and domestically with lack of sun exposure,
maternal obesity, overuse of broad spectrum sunscreens, pigmented skin, intestinal malabsorption, increased
catabolism of vitamin D and other factors (Nozza, 2001).
Prevalence of vitamin D deficiency in pregnancy is considered high in different populations. It vary between 6
and 96% according to the latitude, ethnicity and supplementation of vitamin D, body mass index, season and the
cut-off used to define deficiency of vitamin D. This cut-off has been set between 10 and 20 ng/ml depending on
the study (Weinert, 2015).
25 hydroxy vitamin D cross the placental barrier and, at birth, cord blood 25 hydroxy vitamin D levels are directly
correlated with maternal levels, Plasma levels of vitamin D in the neonate correspond to approximately 60–70%
of maternal levels. In contrast, fetal 1, 25 dihydroxy vitamin D appear to be largely synthesized in the fetal kidney
with some contribution from placenta-derived 1, 25 dihydroxy vitamin D (Perez-Lopez, 2007).
Vitamin D deficiency in neonates secondary to vitamin D deficiency in their mothers is not uncommon and may
lead to hypocalcemia as vitamin D plays crucial role in calcium homeostasis (Camadoo, 2007). Maternal vitamin
D deficiency results in poor transplacental transfer of vitamin D during pregnancy and reduced stores in the
newborns.
During pregnancy, vitamin D has numerous actions in both the mother and the fetus, its deficiency will have
detrimental effects in both. It is essential for fetal skeletal development. Vitamin D deficiency in the pregnant
women has been associated with adverse outcomes to the mother, such as gestational diabetes mellitus and
preeclampsia, and to the offspring, such as seizures small for gestational age newborns and respiratory distress
(Principi et al., 2013).
In their study, Toaima and al, reported a case series of 19 newborn infants presented with symptomatic
hypocalcemia in a 2-year period only. Vitamin D deficiency in both the infants and their mothers was the
attributed cause in all studied patients and out of the 19 patients, nine had an associated unexpected response of
PTH, which might be explained by immature calcium–vitamin D–parathyroid hormone axis at this early age
(Toaimi, 2010).
3 Conclusions
This case illustrates the importance of checking the calcium levels in neonates who present with seizures and to
check their vitamin D status in those found to be hypocalcaemic.
