The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The eVect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p<0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids. (Arch Dis Child 1997;76:325-329)

Dual-energy X-ray absorptiometry (DEXA) is a rapid and precise technique for the assessment of bone mineralization in children. Interpretation of the results in growing children is complex as results are influenced by age, body size (height and weight) and puberty. Conventionally, bone mineral data derived from DEXA have been presented as an areal density [BMD; bone mineral content (BMC, g)/projected bone area (BA, cm2)], yet this fails to account for changes in BMC that result from changes in age, body size or pubertal development. Measurement of BMC and BA of the whole body, lumbar spine and left hip were made in 58 healthy boys and girls using DEXA. The relationship between BMC and BA was curvilinear, with the best fit being that of a power model (BMD = BMC/BAlambda, where lambda is the exponent to which BA is raised in order to remove its influence on BMC). The value of lambda changed when measures of body size and puberty were taken into account (e.g. for lumbar spine from 1.66 to 1.49). Predictive formulae for BMC were produced using regression analysis and based on the variables of age, body size and pubertal development. This provides a method for interpreting the measured BMC which is independent of such variables and a constant reference range for children aged 6-18 y.

The overall incidence (95% confidence intervals) for IBD in Wales was 2.6 (1.87-3.48) cases per 100,000 per year. The incidence for Crohn's disease was 1.36 (0.86-2.04) cases per 100,000 per year, for UC 0.75 (0.39-1.28) cases per 100,000 per year and for indeterminate colitis 0.48 (0.2-0.92) cases per 100,000 per year.

Recently published standards for body mass index (BMI) based on population studies of height and weight in healthy British children allow an easy but indirect assessment of adiposity in healthy children. However, assessment of adiposity based on standards derived from reference populations may not be appropriate for use in subjects with disease states associated with abnormalities of growth and body composition. This hypothesis was tested by comparison between BMI standard deviation scores (SDS) and more direct measures of body fat derived from dual-energy X-ray absorptiometry (DEXA) and skinfold thickness in groups of children, receiving growth hormone, with inflammatory bowel disease, previously treated for malignancy, and healthy controls. Excess adiposity was defined as a body fat greater than the 85th percentile and was compared to a BMI SDS of +1.0. Overall the sensitivity and specificity for a BMI SDS of +1.0 to correctly identify individuals as having excess adiposity was 66% and 94%, respectively, when body fat was measured by DEXA, and 50% and 100% when estimated from skinfold measurements, respectively. There were no significant differences in these statistics whether applied to the individual disease groups or to healthy controls. These findings suggest that BMI under-predicts the prevalence of excess adiposity in children with disease states but surprisingly to no greater degree than that seen in healthy subjects.

Aims-To evaluate the eVects of discontinuing growth hormone (GH) treatment on energy expenditure and body composition, which might help predict those most likely to benefit from early reintroduction of GH treatment in young adult life. Methods-Body composition was calculated from skinfold thicknesses and dual energy x ray absorptometry (DXA). Resting metabolic rate (RMR) and whole body bone mineral content (BMC) were also measured. Measurements were made before stopping treatment, at discontinuation of GH treatment, and two weeks, six months, and one year later in 11 adolescents with growth hormone deficiency (GHD) and five adolescents without GHD who were treated with GH. Measurements were compared with 10 healthy controls, in whom measurements were repeated one year later. Results-During the nine months before discontinuation of GH there were no changes in body composition, RMR, or BMC of patients with GHD, nor diVerences when compared with controls. RMR was reduced by 11.3 kJ/kg fat free mass two weeks after stopping GH in GHD patients and remained suppressed thereafter compared with controls. Percentage body fat increased by 4.3%/year in patients with GHD after discontinuing GH, whereas no changes were noted in control or non-GHD patients at one year. The patients experiencing the greatest reductions in RMR/kg fat free mass at six months showed the largest increases in body fat at one year. No change in BMC was noted in patients one year after stopping treatment. Conclusion-Important metabolic changes occur early after discontinuing GH treatment. In patients whose growth is complete, these changes might be used to predict those most likely to benefit from continuation of GH treatment into adult life. (Arch Dis Child 1999;80:517-523)

Dual‐energy X‐ray absorptiometry (DEXA) is a rapid and precise technique for the assessment of bone mineralization in children. Interpretation of the results in growing children is complex as results are influenced by age, body size (height and weight) and puberty. Conventionally, bone mineral data derived from DEXA have been presented as an areal density [BMD; bone mineral content (BMC, g)/projected bone area (BA, cm2)], yet this fails to account for changes in BMC that result from changes in age, body size or pubertal development. Measurement of BMC and BA of the whole body, lumbar spine and left hip were made in 58 healthy boys and girls using DEXA. The relationship between BMC and BA was curvilinear, with the best fit being that of a power model (BMD = BMC/BAλ, where λ is the exponent to which BA is raised in order to remove its influence on BMC). The value of λ changed when measures of body size and puberty were taken into account (e.g. for lumbar spine from 1.66 to 1.49). Predictive formulae for BMC were produced using regression analysis and based on the variables of age, body size and pubertal development. This provides a method for interpreting the measured BMC which is independent of such variables and a constant reference range for children aged 6–18 y.

Aims-To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). Methods-Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The eVect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. Results-Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN aVecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. Conclusions-Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care.

(3-8 SD below the mean for normal young males) and the lumbar spine BMD was 0-3 g/cm2 . Even allowing for his weight and pubertal delay by comparing the lumbar spine BMD with that of a child with similar bone age it is 4-8 SD below the mean. A luteinising hormone/follicular stimulating hormone stimulation test showed a prepubertal response. Prednisolone treatment was reduced and stopped over the next three weeks. He was commenced on testosterone undecanoate 40 mg on alternative days and continued the elemental diet. Over the next 11 months his growth velocity improved to 9-9 cm/year and he progressed through puberty, achieving Tanner stage III. Repeat DEXA scan I1 months after diagnosis of osteopenia showed great improvement with a significant increase in bone mass and lumbar spine BMD had increased to 0-46 g/cm2, an increase of 74 5%, although the total BMD remained low at 0 743 g/cm2. Fourteen months after diagnosis he is asymptomatic, his haemoglobin, platelet count and albumin are normal, his weight has improved to 42-4 kg and he has achieved a height of 149-5 cm (-3-7 SD). DiscussionGrowth retardation and pubertal delay are well recognised complications of inflammatory bowel disease in childhood. The reported frequency of growth impairment in these children varies from 32 to 88%.3 In addition, an increased rate of cortical bone loss has been found in adults with inflammatory bowel disease.' Several inter-relating factors may have given rise to the osteopenia and growth retardation observed in our child. Malabsorption, protein energy deprivation secondary to a poor diet, and inadequate calcium intake will all result in a reduced rate of bone production.4 Furthermore, steroid treatment has a direct inhibitory effect on bone production and also results in an increased rate of bone loss by inducing hypercalciuria. In view of the early finding of osteopenia it may have been inappropriate to instigate high dose steroid treatment as 255 on 12 May 2018 by guest. Protected by copyright.