Accam scored the goal in the 56th minute after the first half had ended in a goalless draw.
Pedro Santos did incredible stuff when picked the ball and paved his way through Pittsburgh Riverhounds defence, before locating onrushing Accam who positioned himself in the 18-yard box.
The former Chicago Fire forward flicked the ball past goalkeeper Kyle Morton in what stood as the match winner.
Without seven regular starters due to injury or international competition, Columbus Crew produced a relatively make-shift lineup to start the game.
David Acam joined Columbus Crew from Chicago Fire this season and he has shown glimpses of what made him fans favourite during days with the latter.
He has joined four other Ghanaian players in the team, so he is expected to easily adapt.
The 28-year-old who was part of the Ghana team that finished runners-up in the 2005 Africa Cup of Nations in Equatorial Guinea has been snubbed in two consecutive Africa Cup of Nations.