Causes Hyper-function of immune system Infant older Strong bacteria Damaged structures cholesteatoma Unreasonable interventions Drug resistant Poor drainageCauses ◼ Hyper-function of immune system ◼ Infant, older ◼ Strong bacteria ◼ Damaged structures ◼ cholesteatoma ◼ Unreasonable interventions ◼ Drug resistant, ◼ Poor drainage