Emerging Clinical Features of Acute Mastoiditis in Israel: A Registry Based Cohort

Acute mastoiditis (AM) is a severe infection in the young population, with possible life-threatening complications. This study aimed to characterize AM presentation, symptoms and signs, complications, and management, over a period of 10 years.

This large-scale population-based cohort studied "Clalit Health Care" records, to include patients <18 years diagnosed with AM, hospitalized between the years 2008-2018. After validation, we investigated clinical symptoms and signs, pneumococcal vaccination status, complications, laboratory and microbiological parameters, imaging, antibiotic treatment and surgical interventions.

AM was diagnosed in 1189 patients, mean age of 2.71 years and 591 (49.71%) were female. Most presented with protrusion of pinna (83.1%), retro auricular redness (73.5%) and fever (71.8%). Patients <2 years of age had more symptoms (3.8 ± 1.4, opposed to 3.6 ± 1.5, P = 0.006) and showed higher white blood cell count and C-reactive protein values. Local and intracranial complications occurred in 233 (20.8%) and 75 (6.5%) patients, respectively. Complications were associated with increased white blood cell count and C-reactive protein and related to bacterial type, specifically Fusobacterium necrophorum ( P < 0.0001), for which 50% had an intracranial complication. Between the years 2008-2018, Streptococcus pneumoniae -positive cultures decreased (30.9% to 10.3%, P > 0.0001) as opposed to group-A Streptococcus (10.9% to 30.9%, P = 0.002).

This study shows a difference in AM appearance in the <2 years population and the association between white blood cell count, C-reactive protein and microbiology results with the occurrence of a complication. This may play a role in the management process, such as imaging and intervention needs. Although performed during the pneumococcal vaccine era, the disease microbiology was shown to change significantly throughout the study.