Acute mastoiditis: predictors for surgery.

To estimate the incidence of acute mastoiditis and identify predictors for mastoid surgery, a retrospective case record study of 38 children hospitalised for acute mastoiditis in Oslo from 1989 to 1998 was performed. Median age at diagnosis was 18 months and 13 (34%) of the children received mastoidectomy. Compared to the period 1970-1979, the incidence of mastoidectomy was significantly reduced. Only seven children (18%) had experienced acute otitis media prior to the current episode. Symptom duration of 6 days or more prior to hospitalisation and elevated white blood cell counts and C-reactive Protein were predictive for mastoidectomy ((OR = 5.0 (1.0-22.8), (OR = 24.5 (2.5-240) and OR = 10.5 (1-108.8)). Furthermore, total time from symptom onset to hospital discharge was significantly higher in children who received mastoidectomy. We suggest early referral to an otolaryngologic department in children suspected of acute mastoiditis.