Rickets vs. abuse: a national and international epidemic

Abstract

In the May 2007 issue of Pediatric Radiology, the article “Can classic metaphyseal lesions follow uncomplicated caesarean section?” [1] suggested that enough trauma could occur under these circumstances to produce fractures previously described as “highly specific for child abuse” [2]. However, the question of whether themetaphyses were normal to begin with was not raised. Why should this be an issue? Vitamin D deficiency (DD), initially believed to primarily affect the elderly and dark-skinned populations in the US, is now being demonstrated in otherwise healthy young adults, children, and infants of all races. In a review article on vitamin D published in the New England Journal of Medicine last year [3], Holick reviewed some of the recent literature, showing deficiency and insufficiency rates of 52% among Hispanic and African-American adolescents in Boston, 48% among white preadolescent females in Maine, 42% among African American females between 15 and 49 years of age, and 32% among healthy white men and women 18 to 29 years of age in Boston. A recent study of healthy infants and toddlers aged 8 to 24 months in Boston found an insufficiency rate of 40% and a deficiency rate of 12.1% [4]. In September 2007, a number of articles about congenital rickets were published in the Archives of Diseases in Childhood including an international perspective of mother and newborn DD reported from around the world [5]. Concentrations of 25-hydroxyvitamin D [25(OH)D] less than 25 nmol/l (10 ng/ml) were found in 18%, 25%, 80%, 42% and 61% of pregnant women in the UK, UAE, Iran, northern India and New Zealand, respectively, and in 60 to 84% of non-western women in the Netherlands. Currently, most experts in the US define DD as a 25(OH)D level less than 50 nmol/l (20 ng/ml). Levels between 20 and 30 ng/ml are considered to indicate insufficiency, reflecting increasing parathyroid hormone (PTH) levels and decreasing calcium absorption [3]. With such high prevalence of DD in our healthy young women, congenital deficiency is inevitable, since neonatal 25(OH)D concentrations are approximately two-thirds the maternal level [6]. Bodnar et al. [7] at the University of Pittsburgh, in the largest US study of mother and newborn infant vitamin D levels, found deficient or insufficient levels in 83% of black women and 92% of their newborns, as well as in 47% of white women and 66% of their newborns. The deficiencies were worse in the winter than in the summer. Over 90% of these women were on prenatal vitamins. Research is currently underway to formulate more appropriate recommendations for vitamin D supplementation during pregnancy (http://clinicaltrials.gov, ID: R01 HD043921). The obvious question is, “Why has DD once again become so common?” Multiple events have led to the high rates of DD. In the past, many foods were fortified with Pediatr Radiol DOI 10.1007/s00247-008-1001-z