New York State mandates that we send all strep A-negative throat cultures to be confirmed. Frequently, this result is positive for other strains (e.g., B, C, G, and even F). While I treat only strep G, some local physicians treat all strains. Do you recommend treating forms of strep other than A and G?
—Richard Brooks, RPA-C, Geneseo, N.Y.

Having practiced primary-care medicine in New York for more than 16 years, I am somewhat mystified by the statement that the state “mandates” the confirmation of negative group A streptococcal (GAS) throat cultures. In fact, culture is considered the gold standard by which negative rapid-antigen tests for GAS (usually performed in the office setting) should be confirmed. While the antigen test for GAS is fairly specific, it is not sufficiently sensitive to rule out the presence of GAS in the throat. The standard approach to pharyngitis is still to search for— and treat—GAS only. Though other organisms (e.g., viruses, Mycoplasma, non-group A streptococci) can cause a sore throat, none—not even streptococcus G and C—cause the serious complications (i.e., rheumatic fever) seen with GAS. For further discussion, see Boruchoff SE, Weinstein MP. Throat cultures and other tests for the diagnosis of pharyngitis. In: UpToDate. Rose BD, ed. Wellesley, Mass.: UpToDate; 2007, and Clin Infect Dis. 1997;25:574-583.
—Reuben W. Zimmerman, PA-C (102-11)

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