PHILADELPHIA (AP) -- A Pennsylvania woman whose autistic adult son was not recommended for a heart transplant is using an online petition to gather support in a bid to convince a hospital to reconsider.

Karen Corby says doctors at the Hospital of the University of Pennsylvania decided that her 23-year-old son, Paul, would not be recommended for a heart transplant because of psychiatric issues, his autism and the complexity of the process.

The issue reflects the challenges medical providers face in determining who gets organ transplants, when the national demand exceeds the supply.

The University of Pennsylvania Health System can't discuss specific cases but says people being considered for transplants have their entire medical history reviewed before a decision is made.