A man complains of high fever, pain in the area of his right mastoid bone, and purulent discharge from the right ear. One week ago he had a case of URTI. Objectively the right auricle protrudes, the skin behind the ear is hyperemic and pastose; on palpation of the mastoid bone the pain intensifies; the auditory meatus is filled with thick pus, posterosuperior meatal wall sags; the tympanic membrane is red and perforated. Make the diagnosis: