Abstract

Acute rhinosinusitis is estimated to be one of the most common diseases in childhood. Still, the diagnostics and clinical relevance of this disease are controversial.

Bacterial rhinosinusitis cannot be differentiated from mere rhinitis on clinical grounds alone. Abnormal radiologic findings have been found to be common in child and adult volunteers without sinus symptoms and in adults during viral upper respiratory infection. In children, the results of the few placebo-controlled studies on the benefit of antimicrobial treatment of clinically diagnosed acute rhinosinusitis are controversial. Bacteriologic cultures obtained from the middle meatus by rigid nasal endoscopy have been introduced as a way to determine the bacteriology of the maxillary sinus in adults, but they have not been studied in children with acute symptoms.

In this thesis, incidental paranasal abnormalitites were found to be common in healthy school children examined by magnetic resonance imaging (MRI). Some of these abnormalities resolved during a follow-up period of 6 months, but new abnormalities appeared in some children. MRI abnormalities of the paranasal sinuses were found to be much more common in children with acute upper respiratory infections, and most of these abnormalities resolve spontaneously. Children with acute rhinosinusitis confirmed clinically and by imaging did not benefit from cefuroxime treatment as compared to placebo. Pathogenic bacteria (Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis) in the nasal middle meatus during acute upper respiratory infection predicted longer duration of the symptoms and signs of common cold.

Based on these findings, imaging methods should not be used in the diagnostics of acute rhinosinusitis in children. Similarily, incidental imaging findings of abnormalities in the paranasal sinuses or in children with symptoms of acute rhinosinusitis are not an indication for antimicrobial treatment. Because middle meatal pathogenic bacteria were found to predict prolonged symptoms of upper respiratory infection, a randomized controlled trial is needed to evaluate the clinical value of middle meatal culture in identifying the children who would benefit from antimicrobial treatment during acute respiratory infection.