Summary. We evaluated the radiological, biochemical and growth hormone (GH)/insulin-like growth factor-I ... special emphasis on nutritional history, anthropo-.
A T. SOLIMAN ET AL
Radiological, Biochemical, and Hormonal Changes in Malnourished Children with Rachitic Manifestations by Ashraf T. Soliman, MD, Ekram H. Madina, MD, and Mohamed R. Morsi, MD Department of Pediatrics, Alexandria University Children's Hospital, El Chatby, Alexandria, Egypt Summary We evaluated the radiological, biochemical and growth hormone (GH)/insulin-like growth factor-I (IGF-I) changes in 10 children with severe protein-energy malnutrition (PEM) who had rachitic manifestations (group 1), 10 children with severe PEM without clinical signs of rickets (group 2), and 10 children with normal body weight-for-length and -age, suffering from vitamin-D-deficiency with signs of florid rickets (group 3) and 10 normal age-matcbed children (group 4). Serum calcium (Ca2 ), phosphorus (POJ, and albumin concentrations were markedly decreased in the two groups with PEM. Malnourished children with rickets had significantly higher serum alkaline phospbatase (ALP) concentrations compared to the malnourished group without rachitic manifestations. Radiological evaluation of the two groups who had rachitic manifestations revealed demineralization of long bones, thinning of the bony cortex, increased formation of osteoid tissue, and metaphyseal changes including cupping, fraying, and flaring. The incidence of these radiological findings did not differ among the well-nourished and the malnourished groups with clinical signs of rickets. However, the incidence of fracture of the shaft was higher (40 per cent) in the malnourished group compared to the well-nourished group (10 per cent) with rickets. In the malnourished group without clinical evidence of rickets, demineralization and cortical thinning was detected in 40 per cent without significant metaphyseal changes. Basal concentrations of GH and peak GH response to clonidine were significantly elevated and IGF-I concentrations were significantly depressed in the malnourished groups v. the other two groups. There were no significant differences in the fasting and the clonidine provoked GH levels or IGF-I concentrations between the rachitic children (group 3) and the normal children. These data suggest that in rachitic children there is not a major role for circulating GH (and by implication IGF-I) on bone mineralization. However, during malnutrition decreased IGF-I production can slow or stop epiphyseal growth and might contribute to the demineralization of the cortex of long bones. Introduction
Rickets is a syndrome resulting from defective mineralization of the osteoid tissue of the skeleton. The mineralization defect affects primarily the epiphyseal growth plates where the cartilage cells and unmineralized osteoid tissue accumulate. The growth in thickness of the bones is also affected, with deposits of layers of poorly mineralized osteoid. In addition, in both cortical and trabecular bone, resorption in relation to bone remodeling is followed by the deposition of osteoid that fails to mineralize. The clinical and radiological spectrum of rickets is highly variable, depending on the age, the etiology and the duration and severity of the mineralization defect. The bone lesions are most striking, however, at the time of greatest growth velocity.1 Severe protein-energy malnutrition (PEM) can slow and ultimately arrest growth at the end of the long bones. Reduction of cortical bone mass and osteoporosis could result from increased subperiosteal deposition of poorly mineralized bone and still greater
endosteal resorption of bone.2 5 Many investigators deny the association of rickets, a disease of growing children, with severe PEM.6"9 However, in our clinical practice the findings of clinical signs of florid rickets in children with PEM are not uncommon. Growth hormone (GH) has been suggested to be an important regulator of bone growth and mineralization, either directly or indirectly through insulin-like growth factor-I (IGF-I).' 0 "' 2 Moreover, it is proposed that GH can maintain the calcium x phosphorus product (Ca2 + x PO4) at a suitable high level through its various effects on vitamin-D metabolism,'2~'! parathyroid hormone,'6 and intestinal calcium absorption.17 Our aim was to study the radiological, biochemical, and growth hormone/IGF-I profiles in children with severe PEM, with and without clinical signs of rickets, those suffering only from vitamin-D deficiency rickets and compare them with a control group of normal agematched children. Materials and Methods
Correspondence- Ashraf T Soliman, Pediatric Endocrinology, Royal Hospital, Seeb 1331, Code 111, Muscat, Oman. 34
© Oxford University Press 1996
Forty children between the ages of 6 and 24 months were the subjects of this study. They were admitted to Journal of Tropical Pediatrics
Vol.42
February 1996
A. T. SOLIMAN ET AL.
Results Table 1 presents the anthropometric and laboratory data of the four study groups. In the two groups with PEM the percentage weight-for-age (% wt) was significantly decreased compared to the well nourished groups. Serum Ca 2+ and P 0 4 concentrations and, consequently, the CA2+ x PO4 products were signifiJournal of Tropical Pediatrics
Vol.42
February 1996
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