Xia Gibbs Syndrome (XGS) is a rare disorder with different phenotypic
and behavioral manifestations and clinical reflections known to develop
as a result of de novo mutations in the AT-Hook DNA binding motif
(AHDC1).
Our patient was first evaluated in the pediatric psychiatry clinic at the
age of 2 because of speech delay. The patient was followed up with a
diagnosis of cognitive retardation and joint hypermobility was found
as a result of pediatric neurology consultation due to his dysmorphic
appearance. No pathology was found in detailed blood tests and
imaging studies. During the follow-up period, it was determined that
the cognitive skills gained between the ages of 4–4.5 started to regress,
there was no joint attention, but there was stereotypic movements and
limitation in eye contact. In the detailed genetic evaluation performed
due to the deterioration in the clinical course and the addition of the
diagnosis of Autism Spectrum Disorder, a mutation compatible with Xia
Gibbs Syndrome was found in the whole exon sequencing test.
Repeated psychiatric and medical evaluation as part of a multidisciplinary
approach in rare genetic diseases such as Xia Gibbs Syndrome is
important for educational planning and treatment of comorbidities.
With this case, we wanted to emphasize the importance of psychiatric
follow-up and further investigations especially in cases with loss of
acquired skills after diagnosis.
Keywords: AHDC1, autistic disorder, case report, genetic diseases,
intellectual disability, Xia Gibbs Syndrome