The Return of Congenital Rickets, Are We Missing Occult Cases?

Congenital rickets is the term given to fetus born with clinical features of rickets, but those born with biochemical evidence of rickets without obvious clinical features still can be considered occult congenital rickets. Some of the affected babies with this disease have the intrauterine rachitic environment, but a calcium trans-placental pump prevents the fetus from having clinical features of rickets. They may present with hypocalcemia few days after birth or later with more florid features of rickets. Congenital rickets cases born with florid features reported over the last 40 years are few and can be divided into two groups. The first due to severe maternal osteomalacia in which their bones were so decalcified to have enough calcium to be pumped to their fetus. Another group in which newborn babies were hypocalcemic due to other maternal diseases as malabsorption, celiac disease, pre-eclampsia, and prematurity. All inherited rickets cases per se, or as part of other syndromes can be considered congenital rickets. Most cases seen in our region are due to maternal vitamin D deficiency with symptoms becoming obvious when the infants are breastfed, or may present with hypocalcemic convulsions or craniotabes. This is a review of congenital rickets with the aim of shedding light on this potentially acute disease that needs more attention and awareness in the neonatal period to avoid rare serious complications as cardiomyopathy or myelofibrosis and the complications of hypocalcemic convulsions. Congenital rickets cases seen simulate a tip of an ice-burg and its prevention is an important issue, especially with the tremendous urbanization with tall buildings living in sun-deprived flats as the commonest type of residence leading to the increasing incidence of maternal osteomalacia and rickets.