Lauren Buzard was arrested after she rubbed her son's face with feces and other items with dirty linen to allegedly gain the benefit of "exhaustive medical evaluation and attention".
Buzard faces charges of aggravated assault and reckless endangerment of a child after her gruesome act.
Her actions were caught on surveillance cameras that had been placed in the boy's room at Children's Hospital of Pittsburgh, 'WPXI.Com' reported.
Surveillance cameras were placed in the room out of concern that she might be doing something to sicken her child, who had been in and out of the hospital with unexplained illnesses since May, investigators said.
She also allegedly smeared waste on her boy's face and said he had vomited, the report said.
Doctors concluded that Buzard has been actively harming her child in order to gain the benefit of "exhaustive medical evaluation and attention".