A gram-positive Bacillus, which is beta-hemolytic on 5% sheep blood agar, produces a wide zone of lecithinase on egg yolk agar, is nonmotile, and was isolated from the stool of a patient with abdominal pain and watery diarrhea.Because of the patient's existing immunocompromised state, the physician administered penicillin as the antibiotic therapy.The patient's condition did not improve after 7 days of treatment.Which one of the following statements explains the reason for the antibiotic failure?

Question

Quizplus · Accepted Answer

B.anthracis produces beta-lactamase; therefore penicillin and all derivatives would be an ineffective treatment, regardless of how long the antibiotic would be administered.

A Gram-Positive Bacillus, Which Is Beta-Hemolytic on 5% Sheep Blood