Pneumonia is an infection of the lung tissue.
Bacteria, viruses, or fungi cause inflammation in the air sacs (alveoli), which fill with fluid or pus — making it harder for oxygen to cross from the lung into the bloodstream. The most common bacterial cause is Streptococcus pneumoniae; viral causes (influenza, RSV, COVID, etc.) are also frequent.
Score 0–1: less than 2% mortality — candidates for outpatient treatment. Score 2: approximately 9% mortality — admit and monitor. Score 3–5: 15–40% mortality — consider ICU. The risk gradient is steep and the scoring is fast (five yes/no questions).
Pneumonia is an infection of the lung tissue. Bacteria, viruses, or fungi cause inflammation in the air sacs (alveoli), which fill with fluid or pus — making it harder for oxygen to cross from the lung into the bloodstream. Pneumonia kills more than 40,000 Americans every year. It is one of the most common reasons for hospital admission, especially in adults over 65. Among community-acquired pneumonia, the most common bacterial cause is Streptococcus pneumoniae.
Diagnosis combines symptoms, exam (crackles on lung auscultation), chest X-ray (showing infiltrate), and sometimes blood and sputum cultures. CT chest is helpful in unclear cases or when an underlying lung process is suspected. Viral testing identifies flu, RSV, COVID, and other viral causes.
Most healthy adults with mild community-acquired pneumonia can be treated as outpatients with oral antibiotics. Sicker patients need hospitalization for IV antibiotics, oxygen, and monitoring. Patients with severe pneumonia may need ICU care. The decision of inpatient vs. outpatient is informed by severity scores like CURB-65, which assess Confusion, Urea, Respiratory rate, Blood pressure, and age (65+). For viral pneumonia, antivirals (oseltamivir for influenza, paxlovid for COVID, ribavirin for select RSV) shorten illness and reduce complications when given early.
This page is general medical information, not personalized medical advice. If you have questions about your specific health, talk with your Nimbus clinician.
