THE PREVALENCE OF RICKETS AT AUTOPSY IN A SUBTROPICAL CLIMATE: A Pilot Study in Israel

Abstract

During recent years, progress in infant welfare has reduced appreciably the incidence of rickets in the temperate zone. On the other hand, there has been a growing realisation that rickets is a relatively common condition in the tropics and subtropics. JELLIFFE (1955) in his review of infant nutrition comments that " a somewhat paradoxical situation has been reached ", and regards rickets as a debilitating and possibly deforming disorder in tropical infants, living in some urban regions, including the Eastern Mediterranean.Most surveys on the incidence of rickets in warmer climes have been based on clinical diagnosis, though biochemical and radiological studies have been made. With the exception of the report by GILLMAN and GILLMAN (1951) on coloured infants in South Africa, no information on the prevalence of histologically-proven rickets at autopsy outside the temperate zone appears to have been available during recent years. A study on the incidence of rickets in Israeli infants by the authors included clinical, biochemical and radiological examinations. A pilot survey of consecutive postmortem material has now been carried out and the results are reported in this paper.The climate of Israel is subtropical. Out of a total of 4,436 day-hours during the year, over 3,200 clear sunshine hours are recorded, and this percentage is one of the highest in the world. The hot dry Ha/nsin days lead to a loss in direct sun radiation, however. MATERIAL AND METHODSThe investigation dealt with 98 unselected consecutive postmortem examinations of infants between 2 days and 2 years of age during the years 1953-1956. The fourth right costochondral junction was examined in each case. The technique included decalcification in 7 per cent nitric acid during 24 hours, preparation of a paraffin block and staining with haematoxylin-eosin. The diagnosis of rickets, as advised by FOLLIS (1943), was based on the following points : (a) regularity and depth of the columns of preparatory cartilage, (b) amount and regularity of regional blood-vessels and (c) degree of deposition of calcium salts and the amount of osteoid tissue. Positive cases of rickets were graded as severe, moderate or slight.

A Critical Review of the Classic Metaphyseal Lesion: Traumatic or Metabolic?

“…This illustrated the transient but otherwise subclinical nature of rickets in early infancy. The aforementioned autopsy studies also firmly established the predominate subclinical and radiographically occult nature of early infantile rickets [60][61][62][63].…”

“…Incidental rickets was not reported in any classic metaphyseal lesion study nor was it methodically excluded. On the basis of studies reporting rickets in a significant percentage (6.5-22.0%) of screened healthy newborns [57][58][59] and, of greater relevance, deceased fetuses and infants (1-83%) [60][61][62][63], one would have expected some incidental cases of rickets in young infants with classic metaphyseal lesions, potentially confounding a diagnosis of trauma. High rates of rickets are not surprising considering the rising number of reports of subnormal vitamin D levels among pregnant women (54-73%) and their newborns (66-93%) [64][65], data that were not available at the time of the classic metaphyseal lesion publications.…”