Problem 1
A 32 -year-old woman became ill 4 days after the onset of her menstrual period. She presented in the emergency room with fever \(\left(104^{\circ} \mathrm{F}\right.\); normal \(\left.=98.6^{\circ} \mathrm{F}\right)\), elevated white blood cell count \(\left(16,000 / \mathrm{mm}^{3} ;\right.\) normal \(=\) 4,000 to \(10,000 / \mathrm{mm}^{3}\) ), and an erythematous, sunburnlike rash on her trunk and extremities. She complained of fatigue, vomiting, and diarrhea. She had recently eaten at a fast-food restaurant, but otherwise had prepared all her meals at home. The patient described most likely has: A. staphylococcal food poisoning. B. scalded skin syndrome. C. infection with a Staphylococcus saprophyticus. D. chickenpox. E. toxic shock syndrome.
Problem 2
A 57-year-old man arrives at the emergency room complaining of weakness, fatigue, and intermittent fever that has recurred for several weeks. The patient had a cardiac valvular prosthesis implanted 5 years earlier. Physical examination reveals petechiae (pinpoint, nonraised, purplish red spots caused by intradermal hemorrhage) on the chest and stomach. Blood cultures grew catalase-positive, coagulasenegative, cocci. The gram-positive organisms failed to ferment mannitol, and their growth was inhibited by novobiocin. What is the most likely infectious agent? A. Staphylococcus aureus B. Staphylococcus epidermidis C. Staphylococcus saprophyticus D. Streptococcus pneumoniae E. Streptococcus agalactiae
