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Published on: February 29, 2020
[Silent mastoiditis in a 5-month-old infant]
1Klinik für HNO, Hals- und Gesichtschirurgie, Universitätsspital Zürich, Frauenklinikstrasse 24, 8091 Zürich. hno@ksl.ch
Insights
A 5-month-old infant developed a retroauricular swelling, diagnosed as silent mastoiditis caused by Streptococcus pneumoniae. This case is unusual due to the infant's age and lack of typical symptoms, challenging assumptions about maternal antibody protection.
Area of Science:
- Pediatrics
- Infectious Diseases
- Otolaryngology
Background:
- Neonatal and infant infections are typically mitigated by maternal antibodies.
- Mastoid pneumatization, crucial for mastoiditis development, occurs postnatally.
- Otitis media is a common precursor to mastoiditis, but absent in this case.
Observation:
- A 5-month-old infant presented with progressive unilateral retroauricular swelling.
- The infant was otherwise healthy, breastfed, and had no history of otitis media.
- Clinical suspicion of silent mastoiditis was raised.
Findings:
- Computed tomography (CT) scans confirmed the clinical suspicion.
- Intraoperative findings revealed a Streptococcus pneumoniae abscess.
- The diagnosis was established as silent mastoiditis.
Implications:
- This case highlights the possibility of early-onset mastoiditis in infants, even without typical risk factors.
- It suggests that maternal antibodies may not always provide complete protection against certain bacterial infections.
- Further research into infant immune responses and atypical presentations of mastoiditis is warranted.
Abstract:
We report the case of a 5-month-old female infant who developed a progressive unilateral retroauricular swelling without further symptoms in the first 5 months of life. The otherwise healthy infant was breast fed and had no history of previous otitis media. The clinical suspicion of silent mastoiditis was confirmed by CT scans and the intraoperative finding of an abscess due to Streptococcus pneumoniae. The onset is unusual, since mastoid pneumatization develops only after birth, and it is presumed that maternal antibodies should protect the infant from serious infections within the first months of life.
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