From the Guidelines
The best way to evaluate for mastoiditis is through a comprehensive approach that includes clinical examination, laboratory tests, and imaging, with computed tomography (CT) of the temporal bone being the gold standard for detecting bone erosion, abscess formation, and intracranial complications. This approach is supported by recent trends in the management of mastoiditis, which emphasize the importance of prompt and accurate diagnosis to prevent serious complications 1.
Clinical Examination
The clinical examination should include a thorough assessment of the patient's history, symptoms, and physical findings, such as postauricular pain, erythema, swelling, tenderness, and protrusion of the auricle. Otoscopic examination is essential to assess for signs of acute otitis media, tympanic membrane perforation, or otorrhea.
Laboratory Tests
Laboratory tests should include a complete blood count to check for leukocytosis and elevated inflammatory markers like C-reactive protein and erythrocyte sedimentation rate. These tests can help identify patients with severe infection and guide the need for further evaluation and treatment.
Imaging
Imaging is crucial in the evaluation of mastoiditis, with CT of the temporal bone being the gold standard 1. CT can detect bone erosion, abscess formation, and intracranial complications, which are critical for guiding treatment decisions. Magnetic resonance imaging (MRI) may be used as a complementary study when intracranial complications are suspected.
Microbiological Cultures
Microbiological cultures from ear discharge, if present, should be obtained before initiating antibiotics to guide targeted therapy. This is particularly important in patients who have been treated with antibiotics prior to admission, as the risk of developing resistant organisms is higher 1.
Management
The evaluation should be prompt, as mastoiditis can lead to serious complications, including meningitis, brain abscess, facial nerve paralysis, and sigmoid sinus thrombosis. Early diagnosis is critical for appropriate management, which typically includes intravenous antibiotics and possible surgical intervention with mastoidectomy if there is no improvement with medical therapy or if complications are present. A recent algorithm developed by Chesney et al suggests that in uncomplicated cases, treatment can be initiated with intravenous antibiotics, with or without myringotomy and/or drainage or aspiration of any subperiosteal abscess, and CT scanning can be postponed until after 48 hours of treatment or if clinical deterioration occurs 1.
Key points to consider in the evaluation and management of mastoiditis include:
- Prompt and accurate diagnosis to prevent serious complications
- Comprehensive approach that includes clinical examination, laboratory tests, and imaging
- CT of the temporal bone as the gold standard for detecting bone erosion, abscess formation, and intracranial complications
- Microbiological cultures to guide targeted therapy
- Early initiation of intravenous antibiotics and possible surgical intervention with mastoidectomy if complications are present or if there is no improvement with medical therapy.
From the Research
Evaluation of Mastoiditis
To evaluate for mastoiditis, the following methods can be used:
- Clinical symptoms: Fever, coryza, and postauricular signs can be indicative of mastoiditis, although these signs may not always be present 2
- Imaging studies:
- Computerized tomography (CT) scans are highly sensitive for diagnosing mastoiditis 2
- Magnetic resonance imaging (MRI) can show fluid signal in the mastoid, but this is not always indicative of mastoiditis and can be an incidental finding 3
- Cross-sectional imaging can help identify complications of mastoiditis and aid in surgical planning 4
- Laboratory tests:
- C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) can be elevated in cases of mastoiditis, with CRP declining faster in acute cases 2
Diagnostic Challenges
- The diagnosis of mastoiditis can be challenging, especially in cases where the classical postauricular signs are not present 2
- Imaging studies can help identify complications of mastoiditis, but a systematic approach to interpreting these images is necessary 4
- The use of a radiologist-derived systematic checklist, such as the 'mastoid 16', can assist in identifying complications of mastoiditis 4
Treatment and Management
- The management of acute complicated mastoiditis can involve medical, conservative, or surgical treatment, with surgical treatment often resulting in larger reductions in complications 5