Group A Strep: The Stray Dog of Bacterias (Addendum)

In Medical Concepts by Brent Thoma9 Comments

Well consider me embarrassed! Last week I made a post on Group A Strep. As with most of my posts, it was intended to be an overview of a common topic discussing primarily discussing its pathophysiology. However, I definitely should have taken a little more time to delve into the efficacy and necessity of treatment with antibiotics.

A huge thank you to Dr. Lars Peterson (@LarsKristofer), an EM resident from Rochester, NY, who helpfully pointed out this glaring omission with a comment linking to a post by Dr. David Newman, the genius of SMARTEM fame, that outlined the historical background for the use of antibiotics for Group A Strep pharyngitis and concluded that its treatment may do more harm than good. He also has an amazing podcast here. This is at odds with the practice pattern of every physician that I have worked with and the practice guidelines from the Centers for Disease Control, the Infectious Disease Society of America (2012)American Heart Association (2009) and, closer to my home, the Alberta Medical Association.

But that doesn’t mean he’s wrong. Please read his very good review here and podcast here. There is also a 2006 Cochrane review on this very topic that I did not include in my previous post. Its conclusions were much less fierce.

-The evidence for antibiotics preventing post-strep gromerulonephritis is almost non-existent. Truly, no conclusions could be drawn as it was so rare with only 2 cases reported in 10 studies that reported this end-point.

-While the RR of rheumatic fever was decreased by treatment with antibiotics, Dr. Newman pointed out that the lack of rheumatogenic strains found in the modern Western world make the NNT to prevent this end point would be extraordinarily high (estimated at an NNT of 40,000). A 16 hour decrease in symptom duration was also found, but other treatments (Acetaminophen and NSAIDS in this review and corticosteroids in this one) are also effective for symptomatic treatment.

-The Cochrane review concluded that antibiotics did reduce the risk of otitis media, sinusitis and peritonsillar abscess, however, the NNT was high (46 for peritonsillar abscess). However, Dr. Newman’s podcast noted that sinusitis and otitis media were noted more often in earlier studies but did not seem to be affected, retropharyngeal abscess were too extraordinarily rare to be studied for prevention with antibiotics and, while peritonsillar abscess was affected the affect was slight (ARR of 0.8% for an NNT of 125).

-Antibiotics also have complications like anaphylaxis, diarrhea, yeast infections and rash.

All of this being said, is anyone regularly seeing high risk and/or culture-confirmed Group A Strep pharyngitis and not prescribing antibiotics? I still find significant resistance to my “no antibiotics are needed” speech from patients who are at a low risk for having bacterial pharyngitis and want an antibiotic to “fix them,” especially when they “always get antibiotics” for this from the “other doctors” who must be a lot wiser than me. I don’t know if I could pull off “it is a bacteria, but you still don’t need antibiotics” and, while the complications are not common, I feel that I would have difficulty defending myself if my patient developed something I might have prevented had I not ignored generally accepted practice guidelines.

Thanks again to Dr. Peterson for the comment. I am smarter for it and, while I think I’m going to stick with my antibiotics for Group A Strep pharyngitis for the time being (maybe I’m a wimp?), I certainly have a better understanding of the slightness of their benefits and may reassess my position as I get older and wiser.

In the future I will be making more of an effort to post on smaller subjects to allow for a more critical appraisal of the literature. I definitely bit off more than I could chew trying to review all of the non-suppurative Group A Strep pharyngitis complications in a single post and completely dodged an important discussion.

Brent Thoma @boringem

Dr. Brent Thoma is a medical educator, blogging geek, and trauma/emergency physician who works at the University of Saskatchewan College of Medicine. He founded BoringEM and is the CEO of CanadiEM.