Reference data on spontaneous development of growth and weight gain of children with Prader-Willi syndrome are described allowing a better counselling of patients and parents.

We describe three unrelated patients with intrauterine growth retardation (IUGR) and nearly identical bone changes. In certain respects, they share similarities with the Seckel syndrome: small forehead, moderately prominent nose, micrognathia, pronounced intrauterine and postnatal growth retardation, microcephaly, and mental retardation. Differences from the Seckel syndrome include disproportionate shortness of forearms and legs in the first years of life, brachymesophalangy, brachymetacarpy I, V-shaped flare of at least the distal femoral metaphyses, triangular shape of the distal femoral epiphyses, a high and narrow pelvis, proximal femoral epiphysiolysis, and coxa vara. Hormone studies in two cases demonstrated no gross disturbances, especially no deficit of hGH and somatomedin. Two previously reported cases referred to as Seckel syndrome had nearly identical bone changes. The cause of this "new" type of IUGR remains unclear.

Twenty-seven patients with GH insensitivity were identified from 44 possible cases, using a scoring system based on height standard deviation score (SDS), basal GH, insulin-like growth factor-I (IGF-I), IGF-I response to IGF-I generation test, and GH-binding protein (GH-BP) determinations. The 27 cases were from 8 European countries and Australia. Clinical features were as follows: age 2.8-22.6 yr; 12 male, 15 female, 19 prepubertal. Birth weight was median -0.72 SDS (1.75(-)-3.29) and birth length, median -1.59 SDS (0.63(-)-3.63). Hypoglycemia had been documented in 33% of the cases, and micropenis was present in 58% of the males. At assessment, height was median -6.1 SDS (-3.8(-)-10.2), weight was median -3.2 SDS (-0.1 to -5.2), and percentage weight for height, median 111.3 (72-271). Puberty was absent in 2 boys aged 15 yr and in 3 girls aged 13 yr. Bone age was delayed in 19 of the 27 patients. Endocrine investigations showed basal serum GH median 17 micrograms/L (0.5-79), IGF-I values less than 5th percentile, and all except 2, age less than 8 yr, less than 0.1 percentile for age. Percentage increment of IGF-I during IGF-I generation test (hGH 0.1 U/kg body weight daily x 4) did not exceed twice the intraassay coefficient of variation, being less than 0.1 percentile for age. IGF-II was median 135.0 micrograms/L (62-232), all values being less than 5th percentile for age. Insulin-like growth factor binding protein-3 (IGFBP-3) values were median 0.53 mg/L (0.10-1.17 mg/L), all being less than 5th percentile for age. IGFBP-3 values after hGH remained less than 5th percentile. IGFBP-1 values showed the normal fall with age, some being above the normal range; IGFBP-2 values were normal. There was a positive correlation between height SDS and IGF-II SDS (r = 0.66, P < 0.001) and IGFBP-3 (r = 0.64, P < 0.001). Specific binding of [125I]hGH to GH-BP was undetectable in 18 patients and extremely low (< or = 5.6%) in 2. GH-BP was normal (14.2-45.9% radioactivity) in 7 subjects, all female, demonstrating that normal GH-BP does not exclude GH insensitivity.

No abstract

Children treated for acute lymphoblastic leukemia may develop reduced bone mineral density during treatment, but there is little information on the mechanisms involved. In a prospective, longitudinal study on 15 children with ALL, we undertook serial measurements of markers of bone and collagen turnover, insulinlike growth factor (IGF)-I and its binding proteins (IGFBPs)-3 and -2 during the second year of continuing chemotherapy. In eight patients we also measured lower leg length by knemometry. Height SD scores, lower leg length velocity, IGF-I, and markers of bone collagen turnover did not differ significantly from healthy children. However, bone alkaline phosphatase, a marker of the differentiated osteoblast, was lower (mean SD score, Ϫ0.64; p Ͻ 0.0001), whereas procollagen type III N-terminal propeptide (P3NP, a marker of soft tissue collagen turnover; mean SD score, ϩ0.93, p Ͻ 0.05), IGFBP-3 (mean SD score, ϩ0.76; p Ͻ 0.01), and IGFBP-2 (mean SD score, ϩ1.24, p ϭ 0.01) were all higher than in healthy children. IGFBP-3 decreased during episodes of afebrile neutropenia (p Ͻ 0.05). Within 3 mo after completion of treatment, bone ALP increased in all eight patients, but collagen markers showed little change. IGFBP-2 returned to normal posttreatment, but P3NP and IG-FBP-3 remained significantly elevated compared with healthy children (mean SD scores, ϩ1.51 and ϩ1.36, respectively; p Ͻ 0.01). We conclude that continuing chemotherapy was associated with normal growth and bone collagen turnover but enhanced soft tissue collagen turnover. Bone bone alkaline phosphatase was low throughout treatment, which suggests impaired osteoblast differentiation resulting from a direct effect of chemotherapy on bone. Although the effect was reversible, the long-term implications for bone health in survivors remain uncertain. There have been many reports of poor growth in children with acute lymphoblastic leukemia (ALL), especially during periods of intensive chemotherapy, but growth may return to normal during less-intensive periods and may show evidence of further catch-up after completion of chemotherapy (1-13). Of greater concern are a number of retrospective crosssectional studies on survivors of ALL that describe reduced bone mineral density (BMD) at various sites (14 -16). This may be associated with increased fracture risk, reduced peak bone mass, and a theoretical risk of osteoporosis in adult life. However, these previous studies reflect the outcome of earlier treatment protocols, most of which included cranial irradiation and are now obsolete. Current protocols generally use more intensive chemotherapy regimens but avoid cranial irradiation in all but a few high-risk cases. Recently, a number of prospective longitudinal studies have reported that the prevalence of radiologic osteopenia and fracture in children with ALL increases and that BMD decreases during chemotherapy, in the absence of cranial irradiation (17)(18)(19). However, the mechanisms responsible for these observations remain to be elucidated.There are a num...