Acute mastoiditis in pediatric cochlear implant patients - a systematic review

Acute mastoiditis (AM) is a rare but potentially life-threatening condition in pediatric patients, particularly those with cochlear implants (CI) seem to be at higher risk for complications. The aim of this study is to propose a diagnostic and treatment algorithm by analyzing common symptoms, incidence, microbiology, and management of AM in pediatric CI patients. This systematic review includes 20 studies and four own cases, therefore 86 pediatric CI patients diagnosed with AM were enrolled. The research databases Pubmed, Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase und Google Scholar were searched with the terms "acute mastoiditis" and "cochlear implant" and "complications". Inclusion criteria were pediatric patients with CI (<16 years of age) and AM in the CI ear. Exclusion criteria were redundant cases, cases with skin or wound infections. The incidence of AM in this cohort was 1.7 %, with a mean age at the time of AM diagnosis of 45.9 months. Most cases occurred within the first year after CI surgery, with Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae identified as the most common pathogens. Treatment predominantly involved intravenous antibiotics (i.v. AB), with ceftriaxone being the most commonly administered AB. Surgical interventions ranged from grommet insertion, incision and drainage to revision-mastoidectomy or in two cases (2.3 %) even explantation, depending on the severity and course of the infection. Radiological imaging was primarily performed if there was a clinical suspicion of subperiosteal abscess with the need of surgical intervention. Data collection was limited by the mostly retrospective study designs and therefore resulting in partially incomplete data. Based on the collected data we propose diagnostic criteria including swab results and radiological imaging to distinguish between mild and advanced AM leading to treatment recommendations, emphasizing early i.v. AB treatment and tailored surgical interventions to prevent complications and ensure favorable outcomes without the need for CI explantation.