Bone mineral density in children and young adults with Crohn's disease.

Reduced bone mineral density (BMD) has been reported in adults with Crohn's disease (CD). Less is known about abnormal BMD in children and young adults with CD. The aims of this study are to determine the prevalence of low BMD and to evaluate the effect of growth and pubertal development on BMD in children and young adults with CD. One hundred-nineteen patients with CD underwent dual-energy X-ray absorptiometry (DXA) to determine BMD. Anthropometry and pubertal development were measured. Bone age was measured only in patients older than 8 years of age and who had not grown in height during the last year. One hundred-nineteen patients (72 male, 47 female) were evaluated. Seventy percent of patients had BMD z-scores < or = -1.0 and 32% had z-scores < or = -2.0. Weight and height z-scores were significantly associated with BMD z-scores. BMD z-scores based on bone age and on chronological age were highly correlated, except when the chronological age BMD z-score was < or = -2.0. BMD z-score was significantly different between males and females for the group (-1.75 +/- 1.06 vs. -1.08 +/- 1.00), respectively. Children and young adults with CD have a high prevalence of low BMD and routine evaluation by DXA is indicated. In patients with a chronological age-based BMD z-score < or = -2.0, a bone age-based BMD should be considered.

Vertebral compression fractures in pediatric patients with Crohn's disease.

Osteoporosis is known to be a significant complication of Crohn's disease in adult patients. The association of osteoporosis and the development of vertebral compression fractures is well delineated. This case report describes 5 pediatric patients with Crohn's disease in whom vertebral compression fractures associated with a marked reduction in bone density developed. As in adults, the association of osteoporosis and Crohn's disease in pediatric patients is multifactorial, including corticosteroid use, calcium and vitamin D homeostasis, malnutrition, alteration in sex hormones, and site of disease. At the time of diagnosis of the vertebral fractures, the patients' ages ranged from 10.6 to 16.8 years, they had persistent and severe back pain, and 3 of 5 patients had a decrease in height. They were taking 13.7-41.6 mg/day of corticosteroid, and all 5 patients had terminal ileal involvement. Bone mineral density measured by dual-energy x-ray absorptiometry was well below 2SD from the mean in all patients (z-score, -2.31 to -5.11). Because of the high morbidity and mortality associated with fractures that result from low bone mineral density, medical care of all pediatric patients with Crohn's disease should include an evaluation of bone mineral density.

Growth, body composition, and nutritional status in children and adolescents with Crohn's disease.

OBJECTIVE: To examine growth, body composition, and nutritional status in a large sample of children, adolescents, and young adults with Crohn's disease (CD). METHODS: One hundred thirty-two subjects (48 females) with CD, aged 5 to 25 years, and 66 healthy control subjects (37 females) of similar age. Growth, nutritional status, and body composition were measured by anthropometry and dual-energy x-ray absorptiometry. Genetic potential of linear growth was predicted using the adjusted heights of Himes et al. Pubertal status and skeletal age were assessed. Average Pediatric Crohn's Disease Activity Index (PCDAI) and lifetime steroid exposure (in milligrams per day) were obtained from medical charts. The variables were examined in relation to gender and measures of disease activity. RESULTS: Males and females with CD did not differ by age, disease duration, or PCDAI. Males with CD had significantly lower values for growth and nutritional status than control subjects (z-scores for weight: -0.66 +/- 1.18 vs. 0.26 +/- 0.95, P = 0.00002; height -0.81 +/- 1.14 vs. 0.28 +/- 0.93, P = 0.00001; adjusted height -1.05 +/- 1.03 vs. 0.40 +/- 1.03, P = 0.00001) and delayed skeletal age of 0.9 +/- 1.6 years. Impaired linear growth in the males was present regardless of pubertal stage. Associations between disease severity indicators and growth parameters were more consistent for females. CONCLUSIONS: Crohn's disease is associated with impaired growth. Despite similarities in disease duration, activity, and lifetime steroid exposure, growth in males was more impaired. Gender may confer risk for impaired growth in CD.

Risk factors for low bone mineral density in children and young adults with Crohn's disease.

OBJECTIVE: Low bone mineral density (BMD) is a recognized complication of Crohn's disease (CD). The aim of this study was to identify the risk factors for low BMD in pediatric patients with CD. STUDY DESIGN: One hundred nineteen subjects with CD ranging in age from 5 to 25 years were enrolled. BMD of the lumbar spine was measured by dual-energy x-ray absorptiometry. Growth parameters were assessed by examination. Disease-specific variables and use of selected medications were determined by chart review. RESULTS: Powerful risk factors for low BMD z-score included hypoalbuminemia, exposure to nasogastric tube feeds, total parenteral nutrition, 6-mercaptopurine, and corticosteroids. Corticosteroid dosing at a level >7.5 mg/d, 5000 mg lifetime cumulative dose, or >12 months of lifetime exposure were significant risk factors for low BMD z-score. Weaker but significant associations with low BMD z-scores included measures of disease severity such as pediatric Crohn's disease activity index, hospital admissions, and length of hospital stay. Site and duration of disease were not predictive. CONCLUSIONS: The presence of several clinically available factors was predictive of poor bone mineral status in this sample of subjects with CD. Hypoalbuminemia, corticosteroid exposure, nasogastric tube feeds, total parenteral nutrition, and 6-mercaptopurine were the most powerful risk factors for low bone mineral status.