Phelan-McDermid syndrome

       Phelan McDermid Syndrome (PMS)

Phelan McDermid Syndrome (PMS) is also known as 22q 13 deletion syndrome.  It is a genetic condition which is caused by the deletion or other structural change of end of the chromosome 22 in the 22q 13 region or disease causing mutation of the SHANK3 gene.

SIGNS AND SYMTOMS

  • Developmental and Speech delay
  • Sleeping Disturbances
  • Autism Spectrum Disorder
  • Intellectual Deficit
  • Behavioural problems
  • Seizures
  • Structural heart defects
  • Constipation
  • Gastroesophageal reflux
  •  Poor feeding
  • Renal cyst
  • Recurring ear infections
  • Upper respiratory tract infections

STRUCTURAL ABNORMALITIES

  • Microcephaly
  • Macrocephaly
  • Large eyelashes
  • Pointed chin
  • Largely fleshy hands
  • Abnormal spine curvature
  • Bulbous nose
  • High – arched palate
  •  Malocclusions/ widely spaced teeth
  • Hypotonia

CAUSES

Phelan- Mcdermid Syndrome is caused when a piece of DNA is deleted from Chromosome 22, near the end of the chromosome’s long “q” arm or a change in a single gene on chromosome 22 known as SHANK3.

DIAGNOSIS

The assessment starts with a detailed case history and physical examination by paediatrician. Additional studies include a Magnetic Resonance Imaging ( MRI) of the brain. The most important part of the evaluation is the genetic testing. In order to detect whether a piece of chromosome is deleted, a test known as chromosomal microarray is done. Children with symptoms of PMS should further evaluate psychology and psychiatric, speech and language, neurology, nephrology, cardiology and endocrinology.

1) Primary Care/Development Paediatrics

  • Hearing Assessment
  • Visual Assessment
  • Monitoring of height and weight
  • Otolaryngology (ENT)
  • Paediatric dentistry

           2) Psychiatric and Psychology

  • Psychiatric evaluation focusing ASD
  • Cognitive or Developmental Assessment
  • Speech and Language Evaluation/Therapy
  • Adaptive Function Testing
  • Educational Assessment
  • Occupational Therapy

3)  Neurology   

  •        Motor development, coordination, and gait monitoring, as well as conditions that might be associated with hypotonia, like neuromuscular scoliosis and feeding problems
  • Overnight video EEG
  • Structural brain MRI
  • Head circumference up to 36 months

4) Nephrology  

  • Renal and bladder ultrasonography

5) Cardiology    

  • Echocardiogram
  • Electrocardiogram

6) Endocrinology

  • Thyroid function
  • Nutritional assessment

TREATMENT

 There is no specific treatment option for PMS. Treatment is client centered depending on the symptoms and careful screening for associated problems. Treatment options can be given for above mentioned assessments.