Features of PMS

Medical comorbidities

  • Seizures 40%+
  • Increased pain tolerance 88%
  • Hypotonia 75%
  • Recurrent upper respiratory infections 55%, most commonly associated with ear infections 44%
  • Gastroesophageal reflux 44%
  • Sleep disturbance 41%
  • Constipation and/or diarrhea 38%
  • Renal abnormalities, including vesicouretal reflux, hydronephrosis, renal agenesis, extarenal pelvis, dysplastic kidney, and bilateral horshoe kidneys and pyelectasis 38%
  • Lymphedema 22%
  • Cardiac abnormalities


NOTE – This list is meant to introduce you to common features of Phelan-McDermid Syndrome. It is a not a comprehensive list and is not intended to guide your medical care. Please consult your physician for specific health care questions.

PMSF | Phelan-McDermid Syndrome Foundation