A 6-week-old male was brought into the office with a 2-day history of choking spells following a protracted (10 day) period of cold-like symptoms. The parents reported that now the infant would suddenly start coughing and could not seem to catch his breath. They became concerned today because the infant has also started vomiting shortly after these episodes. Copious mucous accompanies the coughing episodes. Upon examination his pulse and respiratory rates were elevated. His WBC was 15,500/ul with 70% lymphocytes. The nasopharyngeal swab did not grow any pathogens on routine lab culture. 16. The child is suffering from what disease? How do you know (hallmark)? Name two virulence factors for this pathogen leading to tissue damage. Why did the routine lab culture not show any results? (4

What is the most likely cause of the patient's condition? Explain how you arrived at this conclusion. What is the most likely causative agent? How did the patient contract the disease?

A 29-year-old previously healthy female presented with a productive cough, fever to 102 oF, and severe headache. She had cervical adenopathy (swollen glands), although she had a nonerythematous throat with no exudate. Chest examination showed crackles bilaterally at the lung base with decreased breath sounds diffusely. This finding was confirmed by chest film that showed bilateral multifocal areas of patchy consolidation. Her neck was not stiff, but because of the severity of the headache, she was admitted to the neurologic service. A spinal fluid was obtained and was negative for bacteria, cryptococcus, and acid-fast smear. Blood cultures and sputum cultures did not produce a pathogen. The patient did not improve on ceftriaxone. On day 3 she was started on erythromycin. On day 4, cold agglutinins were done and were positive. The patient gradually improved although the headache, photophobia, and cough continued for some time QUESTIONS: 1. What is the agent of this disease?…