Prader–Willi syndrome and autism spectrum disorders: an evolving story

Table 3 Characteristics of infants and young children with PWS or autism spectrum disorders

	PWS	Idiopathic Autism
Failure to thrive	+	±
Poor suck, feeding	+	±
Central hypotonia	+	±
Motor delays^a	+	±
Developmental regression	−	±
Impaired social communication^b	Limited data	+
Repetitive interests, behaviors^c	+	+
Delays in play skills^d	Limited data	+

(+) indicates a consistently seen feature, (−) indicates that the feature is not generally present, (±) indicates that the feature is variably present or not consistently found
^aMotor delays are less pronounced in PWS infants receiving growth hormone therapy
^bSocial communication impairment includes: atypical eye gaze, orienting to name, social smiling, and social interest and affect, with reduced expression of positive emotion
^cRepetitive behaviors encompass atypical exploration of toys or objects, including prolonged visual examination, unusually repetitive actions
^dDelays in play skills include motor imitation and functional use of toys (summarized in Zwaigenbaum, 2010 for infants aged 12–18 months)

ISSN: 1866-1955