Evidence-Based Evaluation And Management Of Patients With Pharyngitis In The Emergency Department

Table of Contents

 

1. Abstract
2. Case Presentations
3. Introduction
4. Critical Appraisal of the Literature
5. Etiology And Pathophysiology
6. Differential Diagnosis
7. Prehospital Care
8. Emergency Department Evaluation
   1. History
   2. Physical Examination
   3. The Centor Criteria
9. Diagnostic Studies
   1. Rapid Antigen Detection Testing And Throat Cultures
   2. Diagnostic Studies For Young Children
   3. Other Laboratory Testing
10. Treatment
    1. Pain Relief
11. Special Circumstances
    1. Counseling The Patient Who “Wants” Antibiotics
    2. Fusobacterium And Lemierre Syndrome
    3. Chronic Group A Beta Hemolytic StreptococcusCarriers
12. Controversies And Cutting Edge
    1. Withholding Antibiotics For Group A Beta Hemolytic Streptococcus
    2. Acute Rheumatic Fever
    3. Other Complications
    4. Treatment To Reduce Symptom Duration, Pain, And Contagiousness
    5. Corticosteroids For Odynophagia
    6. Indications For Tonsillectomy
13. Disposition
14. Summary
15. Risk Management Pitfalls In Management Of Pharyngitis
16. Time- And Cost-Effective Strategies
17. Case Conclusions
18. Clinical Pathway For Managing Pharyngitis In The Emergency Department
19. Tables and Figures
    1. Table 1. Infectious Causes For Sore Throat
    2. Table 2. Modified Centor Criteria
    3. Table 3. Summary Of Guidelines For Pharyngitis
    4. Table 4. Antibiotic Treatment Of Group A Beta Hemolytic Streptococcus Pharyngitis
    5. Figure 1. Oral Cavity And Pharynx Anatomy
20. References

Abstract

Pharyngitis is a common presentation, but it can also be associated with life-threatening processes, including sepsis and airway compromise. Other conditions, such as thyroid disease and cardiac disease, may mimic pharyngitis. The emergency clinician must sort through the broad differential for this complaint using a systematic approach that protects against early closure of the diagnosis. This issue reviews the various international guidelines for pharyngitis and notes controversies in diagnostic and treatment strategies, specifically for management of suspected bacterial, viral, and fungal etiology. A management algorithm is presented, with recommendations based on a review of the best available evidence, taking into account patient comfort and outcomes, the need to reduce bacterial resistance, and costs.

Case Presentations

You are working in a community emergency department when a first-time mother brings in her two-and-a-half-year-old daughter who has had a sore throat for 2 days. She has had low-grade fevers and will not eat, complaining of pain. She is not in daycare, looks well overall, and is drinking from a juice box in the examination room. Mom is asking for antibiotics for strep throat and you think to yourself, “Is this an appropriate patient to give antibiotics to?”

The next patient you see is a 20-year-old man who has had a sore throat for 2 days. He is febrile to 38.8°C, has bilateral tonsillar erythema and exudates, and tender cervical adenopathy. He has not been coughing, is able to eat and drink, and does not have any trouble breathing, but he is asking for pain medication. What should you give him? Does he need a test for strep? If so, which one? Does he need antibiotics? If so, what kind? Later that day, you see a 35-year-old woman with 5 days of sore throat, presenting with voice changes. She looks well, but she but swears her voice is not normally this hoarse, and she has odynophagia without any other associated symptoms. Could this be a life-threatening cause of sore throat? Does she need an urgent intervention?

Your last patient is a 65-year-old male smoker complaining of several weeks of sore throat and hoarseness. He has not had a fever or other upper respiratory symptoms. He does not have any known exposures, and reports a gradual worsening of symptoms. You think to yourself, “What is the chance this is not infectious?” What other etiologies should you consider in this patient with sore throat?

Introduction

Pharyngitis is the combination of sore throat, fever, and pharyngeal inflammation,¹ and it is one of the most common chief complaints seen in the emergency department (ED). Sore throat accounted for over 2 million ED visits in 2007.² Emergency clinicians must be able to assess these patients for airway threats and determine an efficient treatment strategy.

This simple presentation is still the cause of much debate and practice variation, with conflicting guidelines for care. The crux of the pharyngitis debate centers around group A beta hemolytic Streptococcus (GABHS), or “strep throat,” which accounts for 20% to 30% of sore throat visits in children^3,4 and 5% to 15% of sore throat visits in adults.⁵ It is estimated that, in the United States, between $224 million and $539 million are spent annually on GABHS in children and adolescents,⁶ not including the costs for the adult cases. This infection has been known to cause both suppurative complications (eg, peritonsillar abscess or otitis media) and systemic complications (eg, acute rheumatic fever or glomerulonephritis).^7-9 The incidence of suppurative complications and acute rheumatic fever are thought to have been reduced by antibiotic use, and they remain a primary consideration for diagnosis and treatment.¹⁰ However, as the incidence of acute rheumatic fever has declined greatly in the United States and other developed countries, the importance of treatment to prevent this complication has come into question.¹¹

This leads to many questions that the emergency clinician must be able to answer, including: Does this patient have strep throat? Are antibiotics needed? What else, if anything, can we use to treat pain? Supplemental questions to those basics include: Could this be something dangerous, such as epiglottitis or a deep neck space infection? Are there other pathogens such as group C Streptococcus or Fusobacterium spp that we should be treating with antibiotics?¹²

While many guidelines exist, including the Infectious Diseases Society of America (IDSA) guidelines from 2012, the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) guideline from 2012, the American Heart Association/American Academy of Pediatrics (AHA/AAP) guideline, and the Centers for Disease Control and Prevention/American Academy of Family Physicians/American College of Physicians (CDC/AAFP/ACP) guideline from 2001, the recommendations conflict, causing confusion about best practices, and this contributes to broad practice variability.¹³ This issue of Emergency Medicine Practice provides a systematic review of the literature in order to provide clarity for best practice.

Critical Appraisal Of The Literature

A literature search was performed on PubMed using the search terms: pharyngitis, tonsillitis, pharyngotonsillitis, streptococcal pharyngitis, and acute rheumatic fever. Titles, abstracts, and full articles were reviewed for content. The National Guideline Clearinghouse (www.guideline.gov) was also searched using the terms pharyngitis and sore throat and, within the practice guidelines, primary sources of literature were reviewed. The Cochrane Database of Systematic Reviews was also referenced using the terms pharyngitis and sore throat. Excluded articles included those regarding sore throat secondary to intubation. Important practice guidelines reviewed included the IDSA publication on streptococcal pharyngitis, the AHA/AAP publication on rheumatic fever and streptococcal pharyngitis, the ESCMID publication of acute sore throat, and the CDC/AAFP/ACP combined practice guideline on principles for appropriate antibiotic use in acute pharyngitis in adults.

These guidelines attempt to be evidence-based, but they fall to consensus for deciding which patients to test and treat (arguably their most important sections), which leads to discrepancies between them. While the literature is rich in studies on group A Streptococcus, monitorrapid antigen detection tests (RADTs), and different treatments for pharyngitis, data are lacking on acute rheumatic fever in the developed world, as its prevalence has sharply declined. Data on other causes of bacterial pharyngitis (eg, groups C and G Streptococcus and Fusobacterium spp) are also limited, as they have been thought to be inconsequential. Recent data on suppurative complications from GABHS are also lacking, as most of the data come from studies done prior to 1975, and it is unknown how these results apply to current conditions.

Risk Management Pitfalls In Management Of Pharyngitis

1. “It was just a sore throat, so I didn’t think she needed to be admitted for intravenous fluids.”
   Pharyngitis can be a simple diagnosis, but it is imperative to make sure patients' pain is adequately controlled so they can maintain an adequate oral intake. Not assessing a patient's fluid status and ability to eat and drink initially and prior to discharge can lead to poor outcomes and readmissions.
2. “I discharged him with viral pharyngitis after a negative RADT. I didn’t expect him to end up in the intensive care unit with multiple septic emboli.”
   Lemierre syndrome is a rare but well-described complication of pharyngitis, normally associated with Fusobacterium spp, not GABHS. It is most commonly seen in adolescent patients shortly outside of the “acute” (3-5 day) pharyngitis window, with internal jugular venous thrombosis and sepsis. Patients should always be given clear return precautions and follow-up plans.
3. “I didn’t ask about his sexual history.”
   Gonorrhea can cause an exudative pharyngitis, and should be considered in the broad differential for pharyngitis. Chlamydia trachomatis, HIV, and herpes simplex virus can all also produce pharyngeal syndromes and symptoms. Failing to take a good history can prevent diagnosis of these conditions.
4. “She told me her voice sounded funny, but it sounded fine to me.”
   Patients presenting with sore throat can have serious airway complications. Voice change should be considered to be a sign of deep space neck infection or epiglottitis and should be further investigated with direct visualization or imaging to identify a cause.
5. “He had a cough, runny nose, and hoarseness, but I still gave penicillin for his sore throat. He had never had an allergic reaction to an antibiotic before.”
   Inappropriate use of antibiotics can lead to unnecessary costs, antibiotic resistance, and allergic or other unpleasant reactions for patient. Antibiotic use should be limited to only those patients with a clear indication. Patients with obvious evidence of viral pharyngitis, or only 0-1 score on Centor criteria should not be treated with antibiotics.
6. “I gave antibiotics, but the patient is very upset that she developed a peritonsillar abscess and had to come back.”
   While antibiotics have been shown to decrease suppurative complications, they can still occur. Patients should be counseled on the possible complications of pharyngitis and given strict return precautions and a follow-up plan.
7. “I never felt under his tongue.”
   Given the broad differential associated with pharyngitis, the emergency clinician’s best tool for success is a thorough history and physical examination. Ludwig angina or a submandibular abscess results in a “woody” induration in the submental space. Forgetting to fully examine the entire oral cavity or associated structures (skin, spleen, etc) can result in missed diagnoses.
8. “The patient reported a penicillin allergy, so I gave cephalexin. I never asked what the reaction was.”
   Penicillin is the treatment of choice for GABHS pharyngitis, but in penicillin-allergic patients, there are other options. Cephalosporins have low cross-reactivity to penicillin, have been proven effective against GABHS, and can be used if a patient had a minor reaction. However, if a patient had a severe allergy to penicillin such as anaphylaxis, Stevens-Johnson syndrome, or other airway involvement, cephalosporins should not be used.
9. “I saw the patient yesterday and diagnosed her with viral pharyngitis. She didn’t need any treatment. I don’t know why she is back.”
   Pharyngitis can be very painful for patients, and even if antibiotics are not prescribed, the emergency clinician should counsel the patient on methods for pain control. NSAIDs, acetaminophen, lozenges, and gargles can all be effective. Even though most of these medications are available over the counter, patients should still be instructed on what to use and how to use them in order to prevent repeat visits.
10. “It was just a sore throat. Why would I think about cancer?”
    Infectious pharyngitis should last only 3 to 5 days, and anyone presenting with a longer course needs a broader differential. In older patients or patients with other risk factors for malignancy (smoking, obesity, heavy alcohol use), it must be considered, or it will most certainly be missed.

Tables And Figures

References

Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.

To help the reader judge the strength of each reference, pertinent information about the study will be included in bold type following the reference, where available. In addition, the most informative references cited in this paper, as determined by the authors, will be noted by an asterisk (*) next to the number of the reference.

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