Overview
Pneumonia is inflammation of the air sacs (alveoli) of one or both lungs. The air sacs fill with pus and fluid, causing cough, fever, and shortness of breath.
It affects hundreds of thousands of people every year; it can be life-threatening, especially in the elderly, infants, and patients with chronic diseases. It can be prevented and treated with vaccines and antibiotics.
Symptoms
Severity ranges from mild to life-threatening:
- Cough (often with phlegm, sometimes bloody)
- High fever (39-40 °C), chills
- Shortness of breath, rapid breathing
- Chest pain (especially when breathing)
- Extreme fatigue, weakness
- Sweating
- Nausea, vomiting, diarrhea
- Loss of appetite
- Confusion (especially in the elderly)
- Low body temperature (in the elderly)
- Bluish color change (lips, nails — cyanosis)
Types
- Community-acquired pneumonia: Most common form, contracted outside hospital
- Hospital-acquired pneumonia: Develops during hospitalization, more resistant pathogens
- Aspiration pneumonia: Food, liquid, or vomit entering the lungs
- Atypical pneumonia: Atypical pathogens such as Mycoplasma, Legionella
Causes
Bacterial:
- Streptococcus pneumoniae (most common)
- Haemophilus influenzae
- Klebsiella, Pseudomonas
- Mycoplasma pneumoniae (atypical)
- Legionella pneumophila
Viral:
- Influenza (flu)
- Respiratory syncytial virus (RSV)
- SARS-CoV-2 (COVID-19)
- Adenovirus
Fungal: In immunocompromised individuals (Pneumocystis, Aspergillus)
Risk Factors
- Over age 65
- Children under 5
- Smoking
- Chronic diseases (COPD, asthma, diabetes, heart failure)
- Weakened immunity (cancer, HIV, immunosuppressive drugs)
- Being bedridden
- Hospitalization (especially ICU)
- Excessive alcohol use
- Swallowing difficulty (post-stroke)
- Malnutrition
- Air pollution
Complications
- Bloodstream infection (sepsis)
- Fluid accumulation in the lung (pleural effusion)
- Lung abscess
- Respiratory failure
- ARDS (acute respiratory distress syndrome)
- Heart complications
- Death
When to See a Doctor
- Fever above 38 °C, chills, shivering
- Shortness of breath, rapid breathing
- Persistent, worsening cough
- Chest pain (especially when breathing)
- Confusion
- Purple lips, nails
- Any respiratory symptom in risk-group people
- Fever in babies under 2 months
Diagnosis and Treatment
Diagnosis:
- Clinical examination (lung sounds)
- Chest X-ray (confirms diagnosis)
- Blood tests: CRP, procalcitonin, white blood cells
- Sputum culture
- Blood culture
- Bronchoscopy (in some cases)
- CT (in case of complications)
- Oxygen saturation
Treatment:
Community-acquired bacterial pneumonia (at home):
- Amoxicillin, amoxicillin-clavulanate
- Macrolides (azithromycin, clarithromycin)
- Doxycycline
- Respiratory fluoroquinolones
- 5-7 days of antibiotics
Hospital admission needed for:
- Over 65
- Serious accompanying diseases
- Low oxygen
- Hypotension, signs of sepsis
- Severe respiratory distress
Hospital treatment:
- Intravenous antibiotics
- Oxygen therapy
- Respiratory support (mechanical ventilation if needed)
- Fluid support
Viral pneumonia:
- Antivirals (oseltamivir for flu; paxlovid for COVID)
- Supportive treatment
Prevention
Vaccines (most effective protection):
- Pneumococcal vaccine: Over 65, chronically ill, children (PCV13, PPSV23)
- Annual flu vaccine
- COVID-19 vaccine
- Hib vaccine (in children)
Other recommendations:
- Quit smoking
- Pay attention to hand hygiene
- Wear a mask around sick people
- Eat healthily, maintain strong immunity
- Get enough sleep
- Keep chronic diseases under control
- Avoid excessive alcohol
- Maintain dental and oral hygiene (for aspiration risk)