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- What are the manifestations of vitamin D deficiency in a newborn?
A neonate born to vitamin D-sufficient mother has vitamin D stores for
8–12 weeks as a result of transplacental passage of 25(OH)D. Therefore, mani-
festations of vitamin D deficiency are seen only in neonates born to severely
vitamin D-deficient mother. These include craniotabes, wide and open fonta-
nelle, rachitic rosary, widening of growth plate, and osteopenia. Craniotabes is
a manifestation of intrauterine vitamin D deficiency as the skull bones grow
rapidly during intrauterine period and early infancy.- What are the manifestations of vitamin D deficiency during infancy?
Human breast milk is a poor source of vitamin D and contains approximately
25 IU/L. Hence, infants who are exclusively breast fed for a prolonged dura-
tion are at risk for the development of severe vitamin D deficiency, unless the
mother is supplemented with supraphysiological doses of vitamin D (4000–
6500 IU/day). Peak age of presentation of vitamin D deficiency is 3–18 months,
and the common manifestations are growth failure, irritability, lethargy,
delayed dentition, recurrent respiratory tract infections, delayed motor mile-
stones, hypotonia (floppy infant), and hypocalcemic seizures. Onset of rickets
during infancy manifests as wrist deformities and rachitic rosary due to rapid
growth of upper limb and rib cage during this period, respectively. Further, the
wrist deformities become more evident as the child starts crawling and com-
monly involve the ulnar side of wrist, due to the rapid growth of distal ulna as
compared to radius.- What are the manifestations of vitamin D deficiency during preschool period
and adolescence?
In a growing child, vitamin D deficiency manifests with deformities in lower
limbs due to rapid growth and weight bearing. These include genu valgum,
genu varum, windswept deformity, and anterior bowing of legs. In addition,
proximal myopathy is a common manifestation of vitamin D deficiency in chil-
dren and adolescence and manifests with waddling gait, even without any
deformity. Chest deformities associated with vitamin D deficiency include pec-
tus carinatum, pectus excavatum, rachitic rosary, and Harrison’s sulcus.
Looser’s zone and vertebral involvement are usually a feature of adult osteoma-
lacia, but presence of these features in a child suggests severe disease. - What are the nonskeletal manifestations of vitamin D deficiency?
The nonskeletal manifestations of vitamin D deficiency include carpopedal
spasm, hypotonia, delayed motor milestones, delayed dentition, enamel hypo-
plasia, proximal myopathy, seizures, and hypocalcemic cardiac failure.
Hypocalcemia due to vitamin D deficiency commonly manifests during infancy
and adolescence because of increased demand of calcium for rapidly growing
skeleton during this period.5 Rickets–Osteomalacia