Mycoplasma

A 28-year-old woman presents with a 2-week history of persistent dry cough, low-grade fever (38.2°C), and malaise. She reports recent exposure to a colleague with similar symptoms. Physical examination reveals scattered crackles on auscultation. Chest X-ray shows bilateral interstitial infiltrates. Blood culture and routine bacterial culture remain sterile. PCR for respiratory viruses is negative. Which of the following is the most likely causative organism?

A 32-year-old man with a 3-week history of cough presents to the clinic. Chest X-ray shows bilateral interstitial infiltrates. Serum cold agglutinin test is positive (titre 1:256). A diagnosis of Mycoplasma pneumoniae infection is suspected. Which of the following antibiotics is the MOST appropriate first-line treatment for this patient?

Which of the following is the characteristic structural feature that distinguishes Mycoplasma from other bacteria?