New or progressive infiltrate on the chest X-ray with one of the following: * Fever > 37.8 °C (100 °F) * Purulent sputum * Leukocytosis > 10,000 cells/μl In an elderly person, the first sign of<unk>  may be mental changes or confusion. Other symptoms may include: * A cough with greenish or pus-like phlegm (sputum) * Fever and chills * General discomfort, uneasiness, or ill feeling (malaise) * Loss of appetite * Nausea and vomiting * Sharp chest pain that gets worse with deep breathing or coughing * Shortness of breath * Decreased blood pressure and fast heart rate
Hospital-acquired pneumonia
Community-acquired pneumonia
Ventilator-associated pneumonia
Idiopathic pneumonia syndrome
Pneumococcal pneumonia
Bacterial pneumonia
Hantavirus pulmonary syndrome
Aspiration pneumonia