12 Respiratory Conditions With Physical Signs Beyond Coughing

8. Pneumonia - The Infectious Respiratory Response

Pneumonia demonstrates how infectious respiratory processes create systemic inflammatory responses that manifest through multiple organ systems, often presenting with physical signs that may overshadow traditional pulmonary symptoms, particularly in elderly or immunocompromised patients. The classic presentation includes fever, chills, and rigors, but the systemic inflammatory response syndrome (SIRS) can produce more subtle signs such as altered mental status, particularly confusion or delirium in elderly patients, which may be the primary presenting complaint. Cardiovascular manifestations include tachycardia that persists despite fever reduction, hypotension indicating possible septic shock, and signs of increased cardiac output such as bounding pulses and warm extremities in early sepsis. The skin may demonstrate poor capillary refill, mottling, or peripheral cyanosis as sepsis progresses, while some patients develop a characteristic heliotrope rash around the eyes or erythema migrans-like lesions with certain atypical pathogens. Gastrointestinal symptoms frequently accompany pneumonia, including nausea, vomiting, diarrhea, and abdominal pain that may lead to misdiagnosis as gastroenteritis, particularly with Legionella or atypical pneumonia. Neurological signs beyond altered mental status may include headache, neck stiffness (without true meningitis), and photophobia, while some patients develop seizures or focal neurological deficits due to septic emboli or metabolic derangements. Laboratory manifestations visible through physical examination include jaundice from hemolysis or hepatic dysfunction, petechiae or purpura from thrombocytopenia or disseminated intravascular coagulation, and lymphadenopathy in cases of atypical pneumonia. The musculoskeletal system may show signs of myositis with muscle tenderness and weakness, while joint pain and swelling can occur with certain pathogens, emphasizing how pneumonia functions as a systemic disease rather than merely a localized pulmonary infection.