PP05.9 – 2366: Neurodevelopmental and immunological features in a child presenting 22q13.2 microdeletion

Introduction Phelan-Mc Dermid syndrome (PMD) is a contiguous disorder resulting from the deletion of the distal arm of chromosome 22, generally implicating the SHANK3 gene on 22q13.3. Patients typically present neonatal hypotonia, developmental and speech delay, autistic features, normal or accelerated growth and minor morphological anomalies. In addition, several patients with 22q13 microdeletion proximal to SHANK3 and typical features of PMD are described. Case description We describe a 7-year old girl presenting a 0.54-Mb interstitial 22q13.2 microdeletion associated with neurological and immunological features. The patient presents different dysmorphic signs and macrocephaly. Neurological features include psychomotor and language retardation, coordination difficulties, repetitive behaviors and perseverations. In addition, the girl was affected by repetitive bronchiolitis since the age of 5 months, allergy to mites, treatment resistant asthma and vernal conjunctivitis. Discussion The chromosomal region deleted in our patient includes a dozen of genes including TNFRSF13C and NFAM1, two genes involved in B-cell development and related to autoimmunity. Therefore, this microdeletion probably explains not only neurodevelopmental anomalies evoking PMD but also immunological features including treatment-resistant vernal conjunctivitis, asthma and allergy. Recently, one other patient with a larger 22q13.2 microdeletion and similar clinical features has been described, thus helping for patient's diagnostic work up. The case illustrates the importance to assess the full clinical picture. Genetic abnormalities might not only explain neurological features but also extra-neurological diseases, important for patients, their follow up and possible treatments.