A Curse Room with a Red Chest in the Binding of Isaac: Rebirth (BOIR)
The Spiked door means the room behind it is a cursed room

The Curse Room is a type of Room in The Binding of Isaac: Rebirth (TBOIR)

To enter a Curse Room, one must go through a Spike door, which deals one half heart damage, both on the way in and on the way out

Curse rooms often do not have enemies inside, but instead may contain: