Pseudohypoparathyroidism: an evolving clinical and biochemical picture
S Joshi & T Cheetham (2008)Royal Victoria Infirmary, Newcastle Upon Tyne, UK. Presented at British Society for Paediatric Endocrinolgy & Diabetes, Swansea, UK
Endocrine Abstracts (2008) 17 P33
Introduction: Children with pseudohypoparathyroidism (PHP) can have a broad range of phenotypic features and biochemical abnormalities. The heterogeneity of this patient group prompted us to review the clinical features of these children in our service.
Methods: We recorded the mode of presentation, clinical features, growth pattern, biochemical profile and progress of 13 paediatric patients with PHP and hypocalcaemia under review in our service over a 11 year period. The criteria for inclusion were patients with hypocalcaemia due to PTH resistance and a diagnosis of PHP with no evidence of Vitamin D deficiency. Data were recorded and analysed using Excel and SPSS.
Results: The age at diagnosis in the 8 female and 5 male patients ranged from 10months to 15years 8months although one relative (supposedly with hypoparathyroidism) was diagnosed in late adulthood. Six were referred because of short stature, 3 obesity, 2 presented with hypocalcaemic seizures and 2 with subcutaneous calcification. TSH was increased in 60% at presentation and 60% had a relevant family history (6 mothers, 2 grand fathers). Median (range) birth weight SDS was −0.99 (−3.13 to 2.68). BMI SDS at diagnosis was 2.35 (−0.27 to 3.79) and 1.3 (0.33 to 2.9) at last review. Median height SDS at presentation was −0.7 but ranged from −4.58 to 3.53. Patients of a pubertal age were short and their small size contrasted with a mid-parental target height of 0.35 S.D. Median final height was −3 S.D. The older at diagnosis, the greater the PTH (P=0.05). Approximately half of the children had learning difficulties.
Conclusions: Paediatricians need to be aware of the heterogeneity of this disorder with growth patterns that include tall stature then centile crossing in later childhood and adolescence. PTH values tend to rise with advancing age and their measurement should form part of the screen for obesity in tall as well as short children.