A 29-year-old male was seen by his primary care physician for a large boil located on his neck. The physician lanced the boil and expressed a large amount of pus. A sample was sent to the laboratory for culture. The culture yielded heavy growth of a yellow pigmented, beta-hemolytic colony. The Gram stain revealed gram-positive cocci in clusters. The organism was catalase positive and Staphylococcus latex agglutination negative. You would:

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DThe organism's characteristics (yellow pigmented, beta-hemolytic colonies, gram-positive cocci in clusters, catalase positive, and Staphylococcus latex agglutination negative) suggest it could be Staphylococcus aureus, but the negative latex agglutination test indicates it might not be. Performing a thermonuclease test (C) can help differentiate S. aureus from other Staphylococcus species, as S. aureus is usually thermonuclease positive. Boiling a suspension of the organism and repeating the latex agglutination test (D) can denature inhibitors and potentially reveal the true identity of the organism, confirming if it is S. aureus or not.

A 29-Year-Old Male Was Seen by His Primary Care Physician