How is it diagnosed?

Diagnosis is based primarily on the clinical presentation of ear pain, toxicity, ear discharge and the appearance of the ear drum on examination. There may be a tender, reddened swelling behind the ear or tenderness to percussion (tapping) over the mastoid bone.

Plain X-rays may show clouding of the air cells but Computed Axial Tomography (CAT) scanning is most useful in showing soft tissue density and thickening of the mucous membrane with granulomatous tissue or fluid within the air cells. It may also help to distinguish acute from chronic mastoiditis.

Routine bacteriological assessment is required to determine the sensitivity of the infecting organisms to antibiotics and audiological assessment to determine any residual hearing loss is needed after recovery.