1. Background

• Streptococcal invasion of the lower respiratory tract leads to a bacterial tracheitis, bronchitis, and/or interstitial pneumonia
• infection may extend to the interalveolar septa & spread by way of the lymphatics to the mediastinal and hilar lymph nodes and then to the pleural surfaces -> pleurisy and effusions
• Group A Streptococcal infections commonly cause upper respiratory tract infections but only rarely do they cause lower respiratory tract infections except after certain viral infections

2. Pathology

• bronchoscopic examination/biopsy of the tracheobronchial mucosa may show necrotic lesions, and ragged ulcers with large amounts of exudate, edema, and localized hemorrhage (hemoptysis)

1. Prodrome

• viral exanthem or influenzae infection

2. Pneumonia

• most often presents as a pneumococcal pneumonia
  • sudden onset
  • shaking chills with high fever (>40.5 C)
  • pleuritic chest pain
  • respiratory distress
  • toxic appearance
• occasionally presents as an H. flu pneumonia
  • insidious onset and only mildly ill
  • cough with low-grade fever

3. Complications

1. Chest X-Ray

• disseminated interstitial infiltration (bronchopneumonia)
• large pleural effusion usually seen
• lobar consolidation vary rare
• hilar adenopathy rarely
• complications

2. Microbiology

• samples: sputum, throat swab, nasopharyngeal secretions, tracheal aspirate, bronchial washings, lung aspirate, pleural fluid
• others: blood, CSF, urine
• cultures, rapid antigen tests
• bacteremia occurs in about 10% of cases

3. Serum

• leukocytosis (15-40) with increased PMN's
• rising serum antistreptolysin titre (ASOT)

1. Medical

• Penicillin G 100,000 U/kg/d tid
• manage complications:
  • due to Group A Streptococcal
  • respiratory
• intubation/ventilation
• treat underlying illnesses