ESPE Abstracts

Background: Congenital proopiomelanocortin deficiency (POMC) gene mutations cause early-onset obesity, hyperphagia and ACTH deficiency. In the subjects with this picture, neuropsychiatric (NP) features were rarely reported. Many Authors described an appetite loss during the topiramate treatment.

Objective and hypotheses: To discuss NP features observed in a POMC deficient patient and to propose a therapeutic attempt to reduce the hyperphagia.

Method: Case report and literature discussion.

Results: We describe an 8-month old male infant who was referred for severe early-onset obesity due to severe hyperphagia. In this patient isolated ACTH deficiency was detected. The MRI was normal. Direct sequencing of the POMC gene revealed a homozygous single substitution C6902T determining a Gln68X substitution. Therefore congenital POMC deficiency was diagnosed. The child spoke his first words and walked alone at 2 years of age. Since 2.5 years, he was followed for neurocognitive development and psychiatric features. At the first evaluation, a neurodevelopmental delay was noticed by the Griffiths Mental Development Scale (Developmental Quotient 64 with disharmonic profile for greater impairment of locomotor, hearing and speech domains) and by a parent-report measures. When the boy was 3.5-year-old, due to the worsening hyperphagia associated with an oppositional defiant disorder, a treatment with topiramate was started with a good response on hyperphagia and behaviour disorder; no side effects were reported. At 6 yrs, an attempt to stop topiramate caused a rapid worsening of NP symptoms leading to a resumption of the therapy. At last NP evaluation at 6.5 years, WPPSY-III cognitive test evidenced a borderline total IQ (87) and significant discrepancy between verbal and performance IQ (verbal IQ: 70, performance IQ: 111). Psychiatric features revealed attention problems and confirmed the oppositional defiant conduct. During topiramate therapy, BMI has not increased.

Conclusion: In patients with congenital POMC deficiency hyperphagia can contribute or be associated to NP problems. Topiramate therapy could be considered.