the LORD smote = Jehovah smote. Chronicles comes in here to explain why. See 2Ch_26:16-21, and note on "Kings" in title of 1 Kings (p. 447).
a leper. One of nine afflicted with leprosy. See note on Exo_4:6. No reason is given here, but it is given in Chronicles according to the object of the latter book. See note above.
several house = a lazar house. See note on 2Ki_15:7.
over the house, or palace: i.e. the king's house, as regent or co-regent.