A 27 yo women develops a dry cough, fever, headache and muscular pains. She was treated unsuccessfully for past week with aspirin and amoxicillin. Three days later she is brought to the ED because of progressive shortness of breath and worsening cough. An x ray of the chest shows scattered interstitial opacities. Treatment with azithromycin is begun and her symptoms rapidly improve. 1. What pathology is occurring here? 2. What is causative organism? 3. Why do beta lactams not work in treatment? 4. What is an associated condition/finding in people who have been infected with this organism?

The main function of the respiratory system is gas exchange (O2 and CO2). Ventilation is the movement of air through the respiratory tract into (inspiration) and out of (expiration) the respiratory zone (lungs).