PPM1D and intellectual developmental disorder with gastrointestinal difficulties and high pain threshold: Case 3 had PANS characterized by severe OCD triggered by Streptococcus infections which improved with IVIg and plasmapheresis and was subsequently diagnosed with Jansen de Vries Syndrome (JdVS) based on a typical truncating mutation in PPM1D exon 6 (c.1547 C>G; p.S516X)16.