can you have a mastoid infection and no drainage?

Answer 1

Yes. The mastoid air cells are small and encased within the very dense petrous (rock-like) temporal bone. If the ear drum remains intact, there will be no drainage from the ear canal. Conversely, if the drum ruptures due to infection, pus will drain out. This is usually caused by the ear infection that led to the mastoiditis.

Until the 1950's, mastoidectomies to drain pus were among the commonest surgical procedures in infants and children. Antibiotics have lessened the need drastically.