Medicine>>>>>Infectious Disease
Question 27#

A college wrestler develops cellulitis after abrading his skin during a match. He is afebrile and appears well, but the lateral aspect of his arm is red and swollen with a draining pustule. Gram stain of the pus shows gram-positive cocci in clusters. Which of the following statements is correct? 

A) The patient will require hospital admission and treatment with vancomycin
B) The organism will almost always be sensitive to oxacillin
C) The organism is likely to be sensitive to trimethoprim-sulfamethoxazole
D) Community-acquired methicillin-resistant staphylococci have the same sensitivity pattern as hospital-acquired methicillin-resistant staphylococci
E) The infection is likely caused by streptococci

Correct Answer is C


Community onset skin infection is often caused by community-acquired methicillin-resistant S aureus (CA-MRSA). Over 63% of S aureus isolates from the community were methicillin-resistant in one study. However, these isolates are different from the methicillin-resistant S aureus seen in the hospital setting. CA-MRSA isolates are sensitive to linezolid and trimethoprim-sulfamethoxazole and to a lesser degree to clindamycin and tetracyclines. They are resistant to beta lactams and erythromycin. In healthy individuals such as the wrestler described, hospitalization and treatment with vancomycin would not be necessary. Telavancin, ceftaroline, and daptomycin are alternatives to vancomycin in some circumstances for the management of community-acquired or hospital-acquired methicillin-resistant S aureus. Streptococci usually cause a rapidly spreading cellulitis without pustule formation.