White Coat Underground

How well do we understand sore throat?

He looked sick—really sick. He was sitting on a stretcher in an ER bay, flushed, breathing a bit quickly, but his youth seemed to compensate for the acuity of his illness, and he didn’t feel nearly as bad has he looked. His fever was 104, his systolic blood pressure was in the 90s, his heart was racing. He’d had a sore throat recently, and rather than getting better started to feel weak, tired, and feverish. His mom finally dragged him in when he wouldn’t stop shivering. His blood work was not normal, and his chest X-ray looked as if he’d inhaled a box full of cotton balls.

** ** ** **


Sore throat is a common problem in primary care. Most of the time it is caused by one of the many cold viruses that continuously circulate, but there’s a catch. Strep throat is an infection caused by caused by a bacterium called group A beta-hemolytic streptococcus (GAS). It can lead to a number of complications, the most important of which is rheumatic fever. Rheumatic fever has a mortality rate approaching 5% and used to be a common cause of severe heart valve disease in the US, but has become much more rare with the use of antibiotics to treat strep throat.

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Strep throat with white exudates on the tonsils (public domain)

Deciding whether or not a patient with a sore throat has strep is one of the daily problems of primary care medicine. Rapid strep tests aren’t all that good. Cultures are very good but take time, and in an acute care setting you often can’t count on a patient to follow up on test results. For a couple of decades, clinicians have used the Centor criteria as a decision tool. It’s not a perfect tool, but if a patient meets all four criteria, they are about 56% likely to have strep on a culture, and if they only have one, they only have a 6.5% chance of having strep. This decision tool helps avoid the overuse of antibiotics in patients who are unlikely to have a bacterial infection.

Unless we’re wrong.

It turns out that the Dr. Centor is a well-known medical blogger, but more important, he hasn’t stopped looking at the sore throat problem. He has just published a report in the Annals of Internal Medicine looking at the microbiology of sore throats, and the results may have a significant impact on how we approach the problem.

The patient I told you about at the beginning of this post did not have strep. He grew Fusobacterium necrophorum from his blood. This anaerobic bacterium had made its way from his throat into his internal jugular vein and from there had spread to several of his other organs. He was a very, very ill young man (but he did fully recover). Septic internal jugular thrombophlebitis due to F. necrophorum is known as “Lemierre’s syndrome” and was thought to be relatively rare, partly due to the heavy use of empiric antibiotics for sore throats. It has been suggested that as we have become more conservative with antibiotic use, Lemierre’s has become more common. Whether this is true or not, Dr. Centor’s report suggests that the risk of Lemierre’s may be much higher than we think.

Centor looked at a number of studies of adolescents and young adults with sore throats and found that a significant percentage of people who tested negative for strep had F. necrophorum in their throat. In fact, it appears that infection with F. necorphorum may be as common as strep in this group.

There are a number of unanswered questions, including what the real risk of Lemierre’s may be, but these findings may end up having significant clinical implications. We don’t have any rapid tests for this bacteria, so we have to evaluate risk and use the available data to make intelligent clinical decisions. Strep is most often treated with penicillin and related drugs. These same drugs are generally effective against F. necrophorum, but it is not uncommon to use macrolides such as azithromycin (Zithromax) as an alternative agent. These drugs do not kill F. necrophormus and I’m going to think twice before using them as an alternative to penicillin.

The evolving story of sore throats is a great example of the changing nature of medical science, and the translation of research into clinical practice. This is what makes it fun.

References

Centor RM (2009). Expand the pharyngitis paradigm for adolescents and young adults. Annals of internal medicine, 151 (11), 812-5 PMID: 19949147

Centor RM, Witherspoon JM, Dalton HP, Brody CE, & Link K (1981). The diagnosis of strep throat in adults in the emergency room. Medical decision making : an international journal of the Society for Medical Decision Making, 1 (3), 239-46 PMID: 6763125

Bliss SJ, Flanders SA, & Saint S (2004). Clinical problem-solving. A pain in the neck. The New England journal of medicine, 350 (10), 1037-42 PMID: 14999116

Comments

  1. #1 Texas REader
    December 3, 2009

    Question: owning a thermometer is considered reasonable to monitor the health of an individual and any children in the home. Why aren’t pulse oximeters considered reasonable to have and use?

    I ask because I’m a healthy 40-something year old but went to the ER after vomiting all night and was told I had pneumonia! I spent 8 days in the hospital due to the pneumonia and what was eventually diagnosed as an electrolyte imbalance.

    I now own a pulse oximeter so I can check my oxygen if I get a cold.

  2. #2 D. C. Sessions
    December 3, 2009

    This is just cool stuff — thanks for posting it, and if you’re in the mood to write more: awesome!

  3. #3 red rabbit
    December 3, 2009

    Cool case. I guess the question you’re trying to resolve at this point is:

    Is it a zebra or merely a hoarse of a different colour?

  4. #4 antipodean
    December 3, 2009

    Excellent Post. Thanks PAL.

  5. #5 Pascale
    December 3, 2009

    I saw several cases of Lemierre’s post-pharyngeal sepsis during my pediatrics residency (not THAT long ago). I hadn’t thought about it in that long (hey, I subspecialized), but as soon as you described the chest xray, the name popped right back into my brain.
    Failure to treat strep correctly can lead to rheumatic fever, but treatment has no impact on post-strep nephritis (yes, the pediatric nephrologist had to get that in). So don’t worry about that one; it happens even if the patient gets appropriate antibiotics.
    Great post!

  6. #6 Kim
    December 4, 2009

    I had a non-strep bacterial throat infection (assuming the strep test was accurate) of some kind about 10 years ago. It was a pretty terrifying ordeal, which I nicknamed the Alien Death Ick. Most frustrating, when someone finally took pity on me after 6 weeks or so and broke the “no strep no antibiotics” guideline I was cured with plain-old keftab. Keftab! If only I’d known I would’ve lied and said I wanted it for acne.

  7. #7 Calli Arcale
    December 4, 2009

    I’d never heard of Lemierre’s before this. I think I represent the common wisdom among the general public when it comes to sore throats: if it’s not strep, it’s nothing to worry about. This post is interesting, but also rather sobering for me as a parent. It also highlights the difficult decisions when balancing the need to prevent long-term consequences of bacterial infections against the desire to avoid breeding resistant bacteria.

    I had strep about a year ago. I hadn’t bothered to see a doctor for several days, partly because of some complications that were going on in my personal life (I was very busy at the time), but mostly because I kept feeling better. I’d feel horrible in the mornings, but fine by evening. I was sure it was just a cold. The goop I kept coughing up? I assumed that to be postnasal drip, not realizing it was actually originating in my throat. (I’m usually congested in November, so I didn’t peg to the lack of nasal congestion.) Only when my daughter started to show the same symptoms did I go in. We both tested positive on the rapid test, and the culture was positive too. After a day of antibiotics, we both felt fine.

    The other time I had strep, back in high school, I also put off seeing a doctor for days because I wrote it off as just a little cold. I could easily see where a person could get Lemierre’s and not realize it for a while.

    red rabbit: GROAN!!!!!

  8. #8 Rev Matt
    December 4, 2009

    Wow, that’s fascinating. I had strep or mono a ton in high school, I wonder if any of those instances were Lemierre’s? Most often it was a purely clinical diagnosis without even a rapid test (if they even had rapid tests back in the old days when I was a teenager).

  9. #9 daedalus2u
    December 4, 2009

    It should be pointed out that sometimes the damage of rheumatic fever and rheumatic heart disease is due to cross reactive antibodies, not actual infection of the heart tissues.

    Another effect that can occur with strep is the production of antibodies that are cross reactive with certain areas in the brain. These can cause choreas, the syndrome is known as PANDAS and also obsessive compulsive disorder.

  10. #10 anthracite
    December 4, 2009

    Great post Pal. I’d love to see the CXR with all the cottonballs. Could you do that or would that violate HIPPA?

  11. #11 red rabbit
    December 4, 2009

    @ Calli: Sorry, I couldn’t help it.

    My rule of thumb with most patients who’ve had a sore throat less than a week: if they have cold symptoms, I neither treat nor swab. No cold symptoms and a not-too-impressive throat: I swab and wait for the results. No cold symptoms and a throat like the one in the photo: I often swab (more for my own learning purposes) and generally treat.

    If it’s outlasted the cold symptoms, or gone on more than a week or so, I generally swab and sometimes treat on spec.

    I don’t think they culture for F. necrophorum here. It makes me wonder if I’m missing these infections and have just been lucky that nobody’s gone on to get Lemierre’s. I may have to ask the lab to consider looking for it.

  12. #12 PalMD
    December 4, 2009
  13. #13 Docmatt
    December 4, 2009

    Several comments. Like many issues in medicine, despite centuries of progress, many common illnesses still don’t have clear answers in diagnosis and treatment. Recently i’ve heard that rheumatic fever and secondary rheumatic heart disease are essentially no longer seen in the Northern hemisphere associated with strep pharyngitis, but still in the Southern hemisphere. The supposition was that we have different strains of Group A strep with different virulence. Also not mentioned above is that the natural course of strep pharyngitis is spontaneous resolution. Treatment primarily speeds resolution. Again it should be emphasized that acute glomerulonephritis incidence is not reduced by treatment.

  14. #14 katydid13
    December 4, 2009

    The one time I got antibiotics without a positive strep test (in fact no strep test), I actually had mono and didn’t find it out until it was too late to drop a class without penalty. I’m still cranky about that. It was a hellish term.

  15. #15 Alexander the Good Enough
    December 5, 2009

    A post with considerable personal interest and with what I believe is an interesting resolution. For about 15 years I dealt with tonsillitis/strep throat several times a year. It starting when I had mono when I was 19 in 1970. That picture of tonsils with exudate is MUCH too familiar; it would hit me like an avalanche and I’d be to the doctor and on antibiotics ASAP. No fun. About that time, while feeling healthy, I swabbed & cultured my own throat. The result was a beta-hemolytic culture that so freaked my micro professor that it went straight into the autoclave the moment he saw it. With some lobbying I no doubt would have qualified for a tonsillectomy, but…

    This unpleasantness persisted until about 1984. I knew that mono was caused by EBV, and that EBV liked to hide out in the tonsils, and that EBV is a member in good standing of the herpes family. Putting 2+2+2 together, it was easy to talk one of my physician friends into prescribing for me a maintenance dose of acyclovir, which had recently become available. It seemed to put a complete stop to the tonsillitis and also resulted in some reduction in the size of my tonsils. Moreover, every time I discontinued the acyclovir, or would get too sloppy with my dosing, I’d have another bout of tonsil trouble. So acyclovir, and later Valtrex, it was for the next 20 years. Worked pretty good; no real problems.

    Then, about 4 years ago, I noticed some of the research reports that were emerging about the effect of vitamin D on the immune system. Turns out that vitamin D has been woefully overlooked, no doubt because there is no money to be made from it. It has proven to be what has been missing from my life for these many decades. As a result, I am healthier than I have ever been and I felt confident enough to discontinue the maintenance acyclovir/Valtrex 2 years ago. My tonsils are now 1/2 to 1/4 the size they had been all of my adult life to, the point where one of them is close to disappearing. In addition, the production of tonsilliths is significantly reduced although not (yet) eliminated in one tonsil. I’ll bet a course of antibiotic may well take care of that, but I’m waiting until I need it for some other reason. And better still, a host of other nagging little infections from chronic sinusitis to toenail fungus have been greatly reduced or eliminated. I take 5000 – 7000 IU per day; good stuff that D.

    Obviously, personal anecdote is not evidence. But it can give one ideas. If I was a clinician treating throat infections, especially chronic ones, one of the first things I would check in the patient is blood levels of vitamin D. I’ve no doubt at all that it has made a major difference for me, and it also seems to have been of significant benefit to several friends and family members.

  16. #16 Alishia
    March 22, 2010

    I’m a Lemierre’s survivor (6+ years now). I just came across this blog…thanks for writing it. Awareness is key.

    For those who say they wait to prescribe antibiotics (hopefully pencillins or similar!) for a week or wonder if they’ve had Lemierre’s…within 3-4 days of the sore throat I had the high fevers, neck pain/swelling, nausea, weakness, and even shortness of breath, and within a week of my sore throat starting, I was on a ventilator. It can move fast! I was put on the wrong antibiotics at first and misdiagnosed. And, it may seem silly, but I will never take z-pak again for a sore throat.

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