Aetiology# | Cumulate incidence |
Infectious aetiology | 97% of pulmonary infiltrates with diagnosis |
Bacterial pneumonia¶ | 60% of pulmonary infiltrates of infectious aetiology |
Streptococcus pneumoniae | 70% of bacterial pneumonia |
Haemophilus influenzae | 10% of bacterial pneumonia |
Staphylococcus aureus | 9% of bacterial pneumonia |
Legionella pneumophila | 6% of bacterial pneumonia |
Gram-negative bacillus | 5% of bacterial pneumonia |
PCP | 20% of pulmonary infiltrates of infectious aetiology |
Mycobacteriosis | 18% of pulmonary infiltrates of infectious aetiology |
Mycobacterium tuberculosis | 80% of mycobacteriosis |
Mycobacterium kansasii, MAC, Mycobacterium fortuitum and Mycobacterium xenopi | 20% of mycobacteriosis |
Virus | 5% of pulmonary infiltrates of infectious aetiology |
Cytomegalovirus | |
Influenza virus | |
Parainfluenza virus | |
Respiratory syncytial virus | |
Fungus | 2% of pulmonary infiltrates of infectious aetiology |
Cryptococcus | |
Aspergillus fumigatus | |
Endemic fungal infections | |
Parasite | 0.5% of pulmonary infiltrates of infectious aetiology |
Toxoplasma gondii | |
Strongyloides stercoralis | |
Multiple organisms | 7% of pulmonary infiltrates of infectious aetiology |
Other+ | 3% of pulmonary infiltrates of infectious aetiology |
Noninfectious aetiology | 3% of pulmonary infiltrates with diagnosis |
Pulmonary oedema | |
Lung cancer | |
Other |
PCP: Pneumocystis pneumonia; MAC: Mycobacterium avium complex. #: incidence of different aetiologies can vary in different geographical areas; ¶: percentage of each microorganism causing bacterial pneumonia is estimated among cases of bacterial pneumonia with identification of aetiology; +: bronchiectasis and pulmonary abscess. Data are based on results from [10, 11, 24].