ESPE Abstracts

Objective: To report the clinical characteristics, diagnosis, treatment and genetic analysis of a case of X-linked acrogigantism(X-LAG).

Methods: The clinical information of a 4-year-old girl due to “growth acceleration for 2.5 years, breast overflow for 3 months, accompanied by intermittent convulsions twice” was retrospectively reported, and peripheral blood DNA was collected for whole exome sequencing and exome-based CNV analysis.

Results: The patient demonstrated a remarkable acceleration growth since 14-month-old, and her height reached 108cm (+5.54SDS) when she was 2 years old and 132 cm (+6.88 SDS) when she was 4 years old. She also had breast overflow and intermittent convulsions when she was 3 years and 9 months old, accompanied by mild facial coarsening, enlargement of hands and feet, snoring and apnea, prone to sweat and weight gain. The GH baseline was >50ng/ml, and not suppressed by the glucose-GH inhibition test. IGF-1 was 912.0 ng/ml(nearly triple the normal upper limit (ULN)). Prolactin was 1355ng/ml(nearly 85 times the ULN). Pituitary MRI revealed a pituitary enlargement with a maximum diameter of 32 mm. Xq26.3 microduplication of the patient’s germline DNA was identified by exome-based CNV analysis. Literature reported that GPR101 is a pathogenic gene in the Xq26.3 region. The parents and younger sister of the proband do not carry the mutation. Bromocriptin treatment was initiated at of 4 years old and levetiracetam was used to control epileptic seizures. However, prolactin levels remained elevated, and seizures persisted intermittently. By 6 years and 1 month, her height had increased to 159cm (+8.8SDS), accompanied by further pituitary enlargement to 38mm and subsequent left eye blindness. Therefore, bromocriptin was discontinued and surgery was performed. Immunohistochemistry showed GH-positive and PRL-positive cells in the pituitary adenoma. The most recent follow-up was conducted two months after surgery, and significant improvement in facial roughness was observed. The patient's height reached 161.5cm and vision in left eye recovered. IGF-1 levels decreased to 259ng/ml, and prolactin levels returned to normal.

Conclusion: X-LAG should be considered when a child under 2 years old presents overgrowth. The treatment of this condition is complex and challenging.