ESPE Abstracts

Introduction: Growth hormone (GH) exerts its effect through insulin-like growth factor 1 (IGF-I), an intracellular signalling molecule whose production is stimulated by STAT-5b after binding to the growth hormone receptor. STAT-5b deficiency, is characterized by short stature, immune dysregulation and chronic lung disease. And these occur as a result of disruption of the growth hormone axis. Our case is an example of STAT-5b gene mutation, which is a rare disease and it has been defined for the last 10 years.

Case: A 12-year-old male patient was admitted to our outpatient clinic with complaints of short stature and skin rash. He was born 900 gr by cesarean section at 26th gestational week and had a 3-month neonatal intensive care hospitalization history. He was hospitalized with severe acute bronchiolitis attack twice, 1 year and 2.5 years old. He was followed up with diagnosis of atopic dermatitis and hyperimmunoglobulin E for the last 3 years. In the family history; his mother’s and father’s height were 150 cm and 175 cm respectively, there was no consanguinity between mother and father, and he had 2 healthy siblings. Anthropometric measurements; his height, weight and body mass index were 134 cm (SDS: -1.9), 25.7 kg (SDS: -2.54), and 14.2 kg/m2 (SDS: -2.15) respectively. The mid parental height SDS of the patient was -1.17. In his physical examination; he had erythematous eczematous lesions around the eyes, cheeks and chin, and xerosis on the hands, prominent forehead and saddle nose. His testicular volumes were 4/4 ml and pubic hair was tanner stage 1. Laboratory examinations revealed low IGF level (98.7 ng/ml SDS: -1.67) and IGF binding protein 3 (IGFBP3) level (3.75 ng/l SDS: -3.56). Bone age was 8 years-old. GH stimulation tests with L-dopa revealed low basal GH levels and reduced GH response (Peak GH of 2.24 ng/ml). Prolactin level was found to be 12.3ug/l. Height velocity was 6 cm per year. A new heterozygous STAT5b mutation (C.1906+1G>A) was detected.

Conclusions: Children with homozygous Stat-5b gene mutation is characterized by severe short stature up to –6SDS, development of bronchiectasis after recurrent severe lung infections and chronic lung disease that may require lung transplantation, dysmorphic findings such as widespread eczema and ichthyosis on the skin, saddle nose and prominent forehead. We reported a case with a new heterozygote mutation whose growth, respiratory problems and immune system were mildly affected.