Pharyngitis is as common as dirt, and for many of us, just about as exciting. Few emergency physicians have a pulse-pounding sense of exhilaration as we walk into the examination room to see another kid with a sore throat.
But pharyngitis is worthy of our attention for several reasons. Although we are ostensibly a group of smart people, we don't seem to find much agreement in the proper approach to the patient with a sore throat. From diagnosis to treatment, controversy abounds. Leading experts offer differing approaches and opinions. Despite pretty strong evidence that viruses cause most cases of sore throat and the knowledge that we really only need to give antibiotics for infections caused by Group A beta-hemolytic streptococci, we really love to treat sore throats with antibiotics. And like just about every other aspect of medicine, there have been advances in evaluating and managing sore throat.
Before talking about what has changed in the evaluation and management of pharyngitis, we should consider what hasn't changed. For starters, we don't know and probably never will know the actual incidence of this complaint. Health statistics data come from patients who seek medical attention for their complaints. Some have suggested that fewer than 20 percent of pharyngitis sufferers actually visit a health care provider. Then, of course, there is the problem of pre-verbal children. The presence of sore throat in these patients must be inferred from their behavior. Nonetheless, we do know that year in and year out, sore throat is one of the top five reasons for physician visits, and physicians will see literally millions of children with sore throat each year.
Another thing that has remained relatively constant over time is the incidence of GABHS across various populations and its relative contribution to the “universe” of sore throats. School-aged children are the most likely to suffer from GABHS infections, but even in this population, viruses are the predominant organisms. This has clear implications for the “shotgun” approach to antibiotic treatment of sore throats.
Penicillin and GABHS
Penicillin is another constant. Despite years of use and concerns of resistance to other antibiotics, GABHS remains exquisitely sensitive to good old penicillin. In fact, when investigators exposed cultures preserved since the pre-antibiotic era to penicillin and did the same for modern cultures, they found no difference in sensitivity. At least one prominent author believes that sensitivity to penicillin is not the whole issue, and I will discuss that later. Nonetheless, most experts recommend penicillin as first-line treatment for GABHS infection in those who are not allergic.
Even with these constants, much about the evaluation and management of pharyngitis has changed over time. The first change predates most of us (even old guys like me). With the introduction of penicillin treatment for GABHS infections, the incidence of rheumatic fever plunged. In most of the developed world, rheumatic fever is a rare disease, though it still occurs sporadically. Even in the United States, there are locations with a higher incidence of rheumatic fever. This is an important issue. If not for rheumatic fever, most physicians would never have a reason to write an antibiotic prescription for a child with a sore throat.
Yes, those children with GABHS infections who receive early antibiotics do seem to feel better a fewer hours sooner than those who get a prescription a day or two later, but if one is solely concerned with preventing rheumatic fever, then GABHS infections need only be treated sometime within the first week or so. (Nine days is the most often quoted limit for intervention.) This leads us to the discussion of how to identify GABHS infection so that it can be treated in the first place.
Perhaps the best way to think about diagnosing GABHS infection is to first consider when it should not be diagnosed. Virtually all expert opinions on the subject begin by telling us that GABHS is highly unlikely in children who have obvious viral symptoms. Patients with conjunctivitis, rhinorrhea, cough, and skin rashes (other than scarlatina) and a sore throat almost certainly have a viral illness, not GABHS. Unless one is practicing in an area with a high incidence of rheumatic fever, neither testing nor presumptive treatment are warranted. But what about the rest? We'll save them for the next column.
Putto A. Febrile exudative tonsillitis: Viral or streptococcal? (Pediatrics