Bone turnover markers and bone mineral status in protein-energy malnourished infants

ABSTRACT

This study aimed to evaluate bone turnover in malnourished infants and to assess their bone mineral status by dual energy x-ray absorptiometry [DXA]. We studied 18 marasmic patients aged 10.55 +/- 7.01 mo [mean +/- SD], 5 kwashiorkor patients aged 18 +/- 6 mo in addition to 7 healthy infants with matched age and sex. For all subjects, serum levels of osteocalcin, parathormone and bone specific alkaline phosphatase were assessed by Elisa and 25 [OH] D3 level by RIA. Urinary excretion of deoxypyridinoline was assessed by Elisa and expressed as nmol/mmol creatinine. Bone mineral content [BMC] and bone mineral density [BMD] were measured by DXA. Osteocalcin was significantly lower in marasmus and kwashiorkor group than control [P=0.02, 0.002]. Marasmus group had a significantly higher osteocalcin level than kwashiorkor [P=0.037]. Compared with control, deoxypyridinoline was significantly lower in marasmus than control [P=0.014] but was insignificantly lower in kwashiorkor with no significant difference between both patient groups. Alkaline phosphatase and parathormone were significantly lower in marasmus than control but not in kwashiorkor. There were no significant differences between the studied groups regarding 25[OH] D3. Bone mineral content was significantly lower in all of the studied regions of both patient groups than control and kwashiorkor patients had a significantly decreased arm and total BMC than marasmus [P=0.07, 0.02 respectively]. Only leg BMD was significantly lower in malnourished patients. There was no significant correlation between biochemical markers and total BMC or BMD. Protein-energy malnourished infants have decreased bone turnover which was more pronounced in marasmus with decreased BMC and non generalized decrease in BMD