Symptoms:

• Cough (may be dry or produce mucus-like, greenish, or pus-like sputum)
• Chills with shaking
• Easy fatigue
• Fever
• General discomfort, uneasiness, or ill feeling (malaise)
• Headache
• Loss of appetite
• Nausea and vomiting
• Sharp or stabbing chest pain that gets worse with deep breathing or coughing
• Shortness of breath

Other symptoms that may occur:

• Excessive sweating or night sweats
• Joint stiffness (rare)
• Muscle stiffness (rare)
• Swollen glands

Signs and tests:

The doctor may hear crackles or other abnormal breath sounds when listening to the chest with a stethoscope. Reduced or absent breath sounds can be an important sign, because it may mean there is a buildup of fluid between the chest wall and lung, called a pleural effusion.

Tests may include:

• Arterial blood gases
• Blood chemistries
• Blood culture
• Bronchoscopy (in certain cases)
• Chest CT scan (in certain cases)
• Chest x-ray
• Complete blood count
• Lung biopsy (in certain cases)
• Serum Cryptococcus antigen test
• Sputum Gram stain
• Sputum immunofluorescence tests (or other immune tests)
• Urine tests (to diagnose Legionnaire's disease)