A 21-year-old man, not previously diagnosed with a developmental disorder, presents for evaluation after taking a leave from college for psychological reasons. He makes little eye contact, does not appear to pick up on social cues, has become disinterested in friends, spends hours each day on the computer surfing the Internet and playing games, and has become so sensitive to smells that he keeps multiple air fresheners in all locations of the home. He reports that he has had long-standing friendships dating from childhood and high school (corroborated by his parents). He reports making many friends in his fraternity at college. His parents report good social and communication skills in childhood, although he was quite shy and was somewhat inflexible and ritualistic at home. What is the least likely diagnosis?
a.
Social anxiety disorder (social phobia).
b.
Obsessive-compulsive disorder.
c.
Autism spectrum disorder.
d.
Depression.
e.
Schizophreniform disorder or schizophrenia