Due to the survival of chronically ill children, exposure to skeletal toxic treatments, and wider availability of bone health measurement technology, osteoporosis in pediatrics has become a widespread problem. A useful concise review is available (J Pediatr 2012; 161: 983-88).
One of the biggest problems is the limited pediatric evidence on which to base treatment decisions.
Specific points regarding osteoporosis and bone health:
- Bone accretion: most of one’s bone mass is reached by late adolescence or early adulthood
- Frequency of bone fractures: in the general population, 1/2 of boys and 1/3rd of girls have sustained a fracture by 16 years of age. Thus, bone pathology should be suspected in those with unusual fractures.
- Pathological fractures: “meaningful” history of fracture history includes a lower extremity long bone fracture, 2 or more upper extremity long bone fractures and/or vertebral compression fracture.
- Testing: due to cost and precision, dual-energy x-ray absorptiometry (DXA) remains most widely used measurement tool. However, quantitative computed tomography (QCT) has some advantages. It is less biased by bone size and directing generates a measurement of volumetric bone mineral density.
- Primary osteoporosis: osteogenesis imperfecta (OI), idiopathic juvenile osteoporosis (IJO), and osteoporosis-pseudoglioma syndrome (related to loss of function in low-density lipoprotein receptor-related protein 5 [LRP5]).
- Secondary osteoporosis: neuromuscular diseases, malabsorption syndromes, medication-induced (glucocorticoids, diuretics), chemotherapy, and radiation treatments.
- 1st line treatment: adequate nutrition –especially adequate calcium and vitamin D and exercise (especially weight-bearing exercise). It is noted that with cystic fibrosis patients there has been a better response to vitamin D3 (cholecalciferol) than D2 (ergocalciferol); as a consequence, the CF Foundation recommends all CF patients receive vitamin D3. With regard to weight-bearing exercise, the data are conflicting regarding its efficacy.
- 2nd line treatment: treat underlying disorder. For example, with inflammatory bowel disease (IBD), treatment of chronic inflammation with infliximab has been shown to improve markers of bone formation. Inflammation in IBD has been shown to play a more important role than glucocorticoid dosing in terms of predicting bone health.
- 3rd line treatment ??? a) “Currently, teriparatide is the only available treatment with anabolic actions on bone.” But, a black box warning has cautioned against its use in pediatric patients b) bisphosphonates: pamidronate, aleondronate, and zoledronic acid. A review of the small pediatric studies, primarily in OI patients, have shown some improvement in fractures, skeletal pain, and mobility. Optimal dose, frequency, and duration remain unknown.
- Safety of bisphosphonates: potential problems include ‘acute phase reaction,’ hypocalcemia, musculoskeletal pain, gastrointestinal side effects, and many other adverse reactions. Atypical fractures and jaw osteonecrosis have been reported in adults.
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