CASE 3
A 3-year-old male presented in the Emergency Room with a three-day history of sore throat, fever and malaise. He was previously healthy, and his mother did not recall which vaccinations he had in the past (he may have missed some). Physical examination: Child appears somewhat toxic and in mild respiratory distress. T=385, P=100, BP = 106/60, RR=30; Throat exam is remarkable for a gray-white exudate covering the tonsils, uvula, and soft palate; neck with multiple small anterior cervical nodes; lungs clear to auscultation, remainder of exam normal. A presumptive diagnosis of Strep throat was made, and child was given oral penicillin, with discharge from the ER. Three days later, the child returns in severe respiratory distress, requiring intubation. Exam at time of intubation revealed the exudate had formed a membrane covering the entire hypopharynx. The child was also noted to have markedly enlarged cervical nodes. The family states the child did not swallow the medicine prescribed. The medical student checks the computer for results of a throat culture taken during previous visit to discover a notation of presumptive C. diphtheria growing.
1. Describe succinctly the disease Diphtheria.
2. Describe the offending organism, its appearance, characteristics and their normal habitat
3. What kinds of hosts are susceptible?
4. How do these organisms gain access to humans?
5. What are the pathogenic mechanisms of this organism that facilitate infection?
6. Where does the toxin gene reside, and how does the organism acquire it?
7. What defenses humans have against these organisms?8. What is the end result of this battle between organisms and humans?
9. How do you diagnose this infection?
10. What will be your therapeutic strategy?
11. How can you prevent it from spreading to others? Prevent its occurrence?
12. What are the problems created by other species?