1. Background

• initially H. flu invades the nasopharyngeal mucosa before spreading to the lower respiratory tract where the organism invades and destroys the mucous membranes producing a bronchiolitis, peribronchiolitis, and/or interstitial lesions.

2. Pathology

• bronchoscopic examination/biopsy of the epithelium of the smaller airways and lung interstitium show PMN or lymphocytic invasion with inflammation, hemorrhagic edema, and extensive destruction.

1. Prodrome

• nasopharyngeal infection

2. Pneumonia

• insidious onset with prolonged course (weeks)
• fever
• cough +/- productive
• respiratory distress
• pleuritic chest pain

3. Complications

1. Chest X-Ray

• lobar consolidation - single or multiple lobar involvement
• disseminated interstitial infiltration (bronchopneumonia) is less common

2. Microbiology

• samples: sputum, throat swab, nasopharyngeal secretions, tracheal aspirate, bronchial washings, lung aspirate, pleural fluid
• others: blood, CSF, urine
• culture and rapid antigen testing
• blood cultures are positive in 70-80% of cases

3. Serum

• moderate leukocytosis with a relative lymphopenia

1. Medical

• Cefuroxime 100 mg/kg/d IV q6h for 7-10 days
• manage complications:
  • due to Haemophilus influenzae
  • respiratory
• intubation/ventilation
• treat underlying illnesses