Development of body proportions in achondroplasia: Sitting height, leg length, arm span, and foot length.

The aims of this study was to construct references for sitting height, leg length, arm span, relative sitting height (sitting height/height), and foot length and to discuss the development for these anthropometric variables in achondroplasia. Sex-specific references covering ±2 SD are presented for ages 2-20 years. Legs and arms in achondroplasia are already at 2 years of age considerably shorter than in the general population and this deviation increases with age. At adult ages, legs are almost 50% shorter than in the general population and arm span roughly 35% shorter. As sitting height is only mildly affected, relative sitting height position develops far beyond normal ranges. Foot length is also not as affected as limbs.

Cushing's syndrome in children and adolescents: a Danish nationwide population-based cohort study.

OBJECTIVE: Cushing's syndrome (CS) affects all age groups, but epidemiologic data in young patients are very limited. We therefore examined the incidence, prevalence and hospital morbidity of CS in children and adolescents. DESIGN: In a nationwide cohort study, we included all Danish citizens aged 0-20 years from 1977 to 2012. Data were obtained from the Danish National Patient Registry using the International Classification of Diseases (ICD) codes and the Danish Civil Registration System. The diagnosis and treatment were validated by means of individual patient charts. Incidence rate of CS patients aged 0-20 years at diagnosis were computed (standardized to the age and sex distribution of the Danish population). The patients were followed for a maximum of 36 years. Standardized incidence ratios (SIRs) of different hospital-recorded outcomes based on the ICD codes in patients with CS compared to the general population were assessed. RESULTS: We identified a total of 40 pediatric patients with CS, yielding an annual incidence of 0.89 cases/106 population (95% confidence interval (CI) = 0.63-1.16). The median age at the time of diagnosis was 13.8 years (interquartile range: 10.5-18.2 years), 58% were female and 70% had adrenocorticotropic hormone-producing pituitary adenomas. During follow-up, CS patients (excluding three malignant cases) were at increased risk of being diagnosed with infections (SIR: 3.24, 95% CI: 1.05-7.54) and infertility (SIR: 4.56, 95% CI: 1.48-10.63). The three patients with an adrenocortical carcinoma died shortly after diagnosis, but mortality was not increased in the remaining patients. CONCLUSIONS: CS is rare in the pediatric population. The risk of morbidity related to infections and infertility is elevated and merits further attention.

A study of the clinical and radiological features in a cohort of 93 patients with a COL2A1 mutation causing spondyloepiphyseal dysplasia congenita or a related phenotype.

Type 2 collagen disorders encompass a diverse group of skeletal dysplasias that are commonly associated with orthopedic, ocular, and hearing problems. However, the frequency of many clinical features has never been determined. We retrospectively investigated the clinical, radiological, and genotypic data in a group of 93 patients with molecularly confirmed SEDC or a related disorder. The majority of the patients (80/93) had short stature, with radiological features of SEDC (n = 64), others having SEMD (n = 5), Kniest dysplasia (n = 7), spondyloperipheral dysplasia (n = 2), or Torrance-like dysplasia (n = 2). The remaining 13 patients had normal stature with mild SED, Stickler-like syndrome or multiple epiphyseal dysplasia. Over 50% of the patients had undergone orthopedic surgery, usually for scoliosis, femoral osteotomy or hip replacement. Odontoid hypoplasia was present in 56% (95% CI 38-74) and a correlation between odontoid hypoplasia and short stature was observed. Atlanto-axial instability, was observed in 5 of the 18 patients (28%, 95% CI 10-54) in whom flexion-extension films of the cervical spine were available; however, it was rarely accompanied by myelopathy. Myopia was found in 45% (95% CI 35-56), and retinal detachment had occurred in 12% (95% CI 6-21; median age 14 years; youngest age 3.5 years). Thirty-two patients complained of hearing loss (37%, 95% CI 27-48) of whom 17 required hearing aids. The ophthalmological features and possibly also hearing loss are often relatively frequent and severe in patients with splicing mutations. Based on clinical findings, age at onset and genotype-phenotype correlations in this cohort, we propose guidelines for the management and follow-up in this group of disorders.

Growth hormone treatment in 35 prepubertal children with achondroplasia: a five-year dose-response trial.

BACKGROUND: Achondroplasia is a skeletal dysplasia with extreme, disproportionate, short stature. AIM: In a 5-y growth hormone (GH) treatment study including 1 y without treatment, we investigated growth and body proportion response in 35 children with achondroplasia. METHODS: Patients were randomized to either 0.1 IU/kg (n = 18) or 0.2 IU/kg (n = 17) per day. GH treatment was interrupted for 12 mo after 2 y of treatment in prepubertal patients to study catch-down growth. Mean height SDS (HSDS) at start was -5.6 and -5.2 for the low- and high-dose groups, respectively, and mean age 7.3 and 6.6 y. RESULTS: Mean growth velocity (baseline 4.5/4.6 cm/y for the groups) increased significantly by 1.9/3.6 cm/y during the first year and by 0.5/1.5 cm/y during the second year. During the third year, a decrease of growth velocity was observed at 1.9/1.3 cm/y below baseline values. HSDS increased significantly by 0.6/0.8 during the first year of treatment and in total by 1.3/1.6 during the 5 y of study. Sitting height SDS improved significantly from -2.1/-1.7 to -0.8/0.2 during the study. Body proportion (sitting height/total height) or arm span did not show any significant change. CONCLUSION: GH treatment of children with achondroplasia improves height during 4 y of therapy without adverse effect on trunk-leg disproportion. The short-term effect is comparable to that reported in Turner and Noonan syndrome and in idiopathic short stature.