Pediatric Pharyngitis

Objectives

Upon finishing this module, the student will be able to:

• List common etiologies of pediatric pharyngitis
• Discuss the evaluation of the “sore throat”
• Discuss the management of Group A streptococcal pharyngitis

Introduction

Acute pharyngitis (defined as an inflammation of the mucous membranes of the pharynx) is a frequent complaint seen in the Emergency Department (ED). It was the principle diagnosis of approximately 1.8 million ED visits in 2010, of which nearly 700,000 were under the age of 15 (~ 2.8% of all ED visits for this age group). (1) Acute pharyngitis is caused by a wide range of etiologies with viruses estimated to cause 80 to 90 percent of cases. (Table 1) Group A streptococci (GAS) is the most common bacterial etiology (15 to 35 percent) of pediatric pharyngitis and the one for which treatment with antibiotic therapy is generally recommended. Although typically self-limited and uncomplicated, the clinician must be alert for the rare and potentially life-threatening diseases that may initially masquerade as a “sore throat”.

Table 1.  Selected Etiologies of Sore Throat

Initial Actions and Primary Survey

The focus of the primary survey is to identify those children with serious and potentially life-threatening “sore throats”. The initial evaluation of any patient with a chief complaint of sore throat, as with any ED patient, should begin with a rapid primary survey:

Before entering the room, quickly review the chief complaint, nurse’s note, and vital signs. Fever and tachycardia are common findings in pediatric patients with acute pharyngitis. However, hypoxemia, hypotension and\or significant tachypnea are not and suggests another process may be present.

Upon entering the room, check to see if the child is sitting comfortably in the parent’s lap or playing on their parent’s cell phone. This child isunlikely to be suffering from a serious or life-threatening cause of a sore throat. However, a child who is drooling, refusing to lay back and\or leaning forward, in severe distress, obvious agitation (beyond that expected from fear of white coats), confusion, or lethargy, all suggest a serious or life-threatening illness and require preparation for resuscitation and possible airway management.

Evaluation of the ABC’s

Airway

1. The patient’s airway is of utmost priority in any patient with a sore throat.
2. Is the airway intact?
   • If the patient is able to speak in normal sentences (age appropriate) with their normal voice, then theairway is intact.
   • If stridor is present, consider a foreign body or epiglottitis.
   • If the patient is drooling, the patient may be in severe pain, or consider a foreign body or epiglottitis.
   • If the voice is abnormal, consider several processes. Hoarseness, in the setting of cough or coryza, suggests a viral etiology. A muffled or hot potato voice suggests peritonsillar or retropharyngeal abscess, tonsillar enlargement (such as with infectious mononucleosis), or can be present with epiglottitis.

Breathing

1. Breathing is normal in most cases of acute pharyngitis.
2. Abnormal respiratory findings suggest that the sore throat is part of a constellation of symptoms of a systemic illness, such as an acute viral upper respiratory infection, viral or mycoplasma pneumonia, or the child is seriously or critically ill.

Circulation

1. Tachycardia is common in children, especially if associated with fever or pain.
2. Hypotension or other signs of poor perfusion (weak pulses, delayed capillary refill, mottling of skin) are not expected and suggest the emergent need for resuscitation and the search for serious or life threatening etiology.

After the initial primary survey is completed, an appropriate history and physical examination should be obtained. Several key components of the history and physical examination on secondary survey are:

History

• Onset, acute vs. gradual?
  • Pharyngitis due to an infectious etiology is usually acute in nature.
• Duration?
  • Pharyngitis due to viral and most bacterial etiologies are usually self- limited and resolve in 5 to 7 days.
  • A sore throat lasting longer than 7 days may require a more extensive evaluation.
• Course?
  • A progressive, worsening course increases the likelihood of a more serious etiology, such as peritonsillar or retropharyngeal abscess, or Lemierre syndrome.
• Location of the pain?
  • Unilateral pain suggests a possible foreign body, retropharyngeal abscess, or Lemierre syndrome.
• Is there a fever?
  • The history of fever suggests an infectious or inflammatory etiology of the pharyngitis.
• Is there a cough or other upper respiratory complaints?
  • Cough and coryza are usually not present with GAS pharyngitis and their presence suggests a viral etiology.
• Is anyone else ill at home\day care\etc.?
  • The presence of other individuals with similar symptoms suggest an infectious etiology?
• Recent dental work or oral surgery?
• Recent oral procedures increase the likelihood of a surgical site infection?
• Sexually active and sexual orientation?
  • Individuals who engage in oral sex have an increased risk of acute pharyngitis due to Neisseria gonorrhoeae.
  • Acute retroviral syndrome due to human immunodeficiency virus may present with fever and acute non-exudative pharyngitis as components of the symptom complex.
  • Consider these etiologies in appropriate individuals who do not have another apparent cause of their symptoms.

Physical Examination

• Eyes
  • Normal – Typical of GAS pharyngitis
  • Conjunctivitis, drainage, etc. – Suggests viral etiology
• Nose
  • Presence of rhinorrhea suggests viral etiology
  • Coryza may be seen in those children less than 3 years of age with GAS pharyngitis
• Throat
  • Presence of trismus – Suggests involvement\involvement of the pterygoid muscle and is frequently seen with peritonsillar abscesses and odontogenic infections.
  • Swelling
    • Unilateral tonsillar or soft palate – consider peritonsillar abscess
    • Floor of mouth – consider Ludwig’s angina
    • Generalized – Including tongue and lips, consider angioedema
  • Tonsils
    • Bilateral enlargement, injection, exudates – Frequently seen in both viral and bacterial pharyngitis
    • Adherent exudate or membrane, with bleeding when removed – Consider diphtheria, especially in the setting of incomplete immunization history
  • Pharynx
    • Vesicles or ulcers – Frequently viral etiology
    • Petechiae (palatal)
      • May be found in GAS pharyngitis and infectious mononucleosis.
      • Should not be found elsewhere on the body
• Neck
  • Presence of adenopathy – Anterior vs posterior
    • Found in both bacterial and viral pharyngitis.
  • Swelling
    • Unilateral swelling and tenderness concerning for Lemierre syndrome, peritonsillar or odontogenic abscess.
    • Bilateral swelling\adenopathy – Consider diphtheria.
  • Limited range of motion due to pain – Frequently seen with severe pharyngitis, but must also consider more serious etiologies such as retropharyngeal abscess, neck abscess and Lemierre syndrome.
• Abdomen
  • Hepatomegaly\splenomegaly – Suggests infectious mononucleosis
  • Generalized tenderness – May be present with GAS pharyngitis
•  Skin
  • Rashes are frequently found on patients with both viral and bacterial pharyngitis.
  • Scarlet fever – Erythematous, sandpaper rash that typically spares periorally and is more apparent in the axillae and groin. Pastia’s Lines are lines of hyperpigmentation seen in the skin folds.

Symptomatic treatment should be initiated in the ED for the majority of patients, including analgesia and rehydration, if required. Typically, oral acetaminophen or ibuprofen and oral rehydration is adequate. However, narcotics (oral or intravenous) and intravenous fluids may be required, particularly in those patients who are unable to tolerate the oral route.

Group A Streptococcus (GAS) Pharyngitis

The typical presentation of GAS pharyngitis is that of a relatively acute onset of sore throat. Pain is generally bilateral, but may be somewhat worse on one side. Additional symptoms frequently include fever, headache, generalized malaise, and abdominal symptoms. Children between 5 and 15 years of age are most commonly affected with the highest incidences in the 5 -7 and 12 -13 age groups, with incidence then declining with age. GAS pharyngitis is commonly considered to be unusual in children less than 3 years of age, however one study showed a 35% positive culture rate in the 22 to 35 month age group, and declining to 17% for infants less than 12 months of age. The symptoms and signs are frequently atypical in children less than 3 years of age, with coryza, excoriation of the nares, and generalized adenopathy occurring. GAS pharyngitis occurs year round, but its highest incidence is in the late fall to early spring. The presence of a family member with GAS pharyngitis increases the risk that another family member will also develop GAS pharyngitis and this includes the < 3 years of age group as well.

Classic physical findings include fever, cervical adenopathy, and posterior pharyngeal and tonsillar erythema and exudates. The typical scarlet fever rash and petechiae involving the soft palate somewhat specific but are also uncommon. Cough and rhinorrhea are generally absent.

Diagnostic Testing

Once serious and life-threatening causes of sore throat have been eliminated, based on the history and physical examination, the primary goal of diagnostic testing is to confirm or exclude GAS as the etiology. Laboratory studies that are frequently considered are the following:

• White cell count and differential: The white blood cell count has little utility in the evaluation of uncomplicated acute pharyngitis as it cannot reliably differentiate viral from bacterial infections. The white cell differential may assist in the presumptive diagnosis of infectious mononucleosis. Values suggestive of infectious mononucleosis include: > 50% lymphocytes, > 10% atypical lymphocytes, or elevated absolute lymphocyte or atypical lymphocyte counts. The hematologic findings vary based on the patient’s age as well as the time since onset of symptoms (peaking during the second week of the illness). Neutropenia may also be seen.
• Heterophile antibody test: The test (also commonly called “monospot” or “mono test”) is based on detecting the presence of IgM “heterophile” antibodies that are induced by an Epstein-Barr virus infection. A variety of the tests are on the market. Overall, the tests are 85% sensitive and 97% specific. However, the tests are less sensitive in children early in the illness (25% false negative in 1st week) and under 12 years of age (25-50%).
• Throat culture: Culture on sheep blood agar of the posterior pharynx is generally considered the “gold standard” for the diagnosis of GAS. However, the culture atmosphere and media additives are not standardized and can impact the sensitivity of the culture. The site from which the sample is obtained is important as sampling from the tonsillar surface yields the heaviest growth as compared to the posterior pharynx and much more than other locations in the mouth. In addition, culture results are not available for one to two days. Cultures are unable to distinguish actual infection from colonization and may be falsely negative in 10%. The amount of growth on the culture is not able to distinguish colonization from infection.
• Rapid Antigen Detection Tests (RADT): A variety of RADT are available for the detection of GAS. In most RADT, test specific swabs are used to collect samples from the tonsillar and posterior pharyngeal surfaces and GAS cell wall antigens are extracted and then detected using an immunoassay. Results are usually available in 10 to 60 minutes. Although most RADT are highly specific (~ 95%), their sensitivity may be highly variable (70 to 90%). Factors affecting sensitivity include test performance, operator factors, and antigen load. As with cultures, the sample collection technique and sampling site is extremely important. A previously positive RADT becomes negative within 18 to 24 hours of starting antibiotic therapy.
• Clinical Decision Rules: No single element of the history or physical examination is able to accurately diagnose GAS pharyngitis. Over the years, several clinical decision rules have been developed. Currently the Centor score and its revised McIsaac score are frequently mentioned in treatment guidelines. The Centor score is composed of 4 factors and the McIsaac score revised the Centor score to include age. Both demonstrate an increasing probability of GAS pharyngitis with increasing scores. (Table 2) It has been suggested that those patients with a low probability of GAS may not require testing or treatment and those with a high score could be treated without testing. A recent study of greater than 200,000 patients in an outpatient setting, confirmed that both scores are able to identify patients with increasing probability of GAS pharyngitis. However, patients at low risk (scores of 0 or 1) still had probabilities of 7-8 % and 12-14 %, respectively, of being GAS positive.

Table 2 Centor and McIsaac Scores

Adapted from Funamura, JL, Berkowitz CD:  Applicability of a scoring system in the diagnosis of streptococcal pharyngitis.  Clin Pediatr  1983;22:622-6 and McIsaac WJ, White D, Tannenbaum D, Low DE:  A clinical score to reduce unnecessary antibiotic use in patients with sore throat.  Can Med Assoc J  1998;158(1)75-83.

Treatment

After potentially serious\life-threatening diseases are excluded, the main treatment decisions are to determine the likelihood of GAS pharyngitis and if antibiotics are indicated. A number of United States and International treatment guidelines have been published. The guidelines differ significantly, particularly in the use of RADT and the decision to use antibiotics. Recent guidelines from the United States with applicability to pediatric patients will be used here.
The use of antibiotics, in the setting of GAS pharyngitis, is thought to reduce the risk of rheumatic fever, suppurative complications (ex. mastoiditis, acute otitis media and sinusitis, peritonsillar abscess, cervical lymphadenitis), decrease the risk of close contacts acquiring the disease, and decrease the severity of the patient’s symptoms. The use of antibiotics must be balanced against the societal risk of the development of antibiotic resistance and the patient risks of antibiotic associated adverse events (ex. allergic reaction, diarrhea, C. difficile colitis).
The recent guidelines for pharyngitis management by the Infectious Disease Society of America and the Institute for Clinical Systems Improvement are summarized in Table 3. In brief, only children with a test (RADT or culture) positive for GAS should receive antibiotic therapy and testing should only be done for patients with symptoms of acute GAS pharyngitis and lacking symptoms of a viral illness. Table 4 lists suggested antibiotics and doses. Although recommended in penicillin allergic patients, both azithromycin and clarithromycin are known be at risk for GAS resistance and the prescriber should consider this.

Table 3 GAS Treatment Guidelines

*Infectious Disease Society of America – Reference 9

^Institute for Clinical Systems Improvement – Reference 15

Table 4.  Antibiotic selection and dosing

Reference 9

On discharge, patients and parents should be advised to provide acetaminophen or ibuprofen for pain and fever control and to encourage adequate fluid intake. Patients should be re-evaluated in 48 to 72 hours if they are not symptomatically improving and immediately if they worsen in any way (ex. Increasing pain, inability to swallow, inability to take adequate oral fluids and medications, drooling, or difficulty breathing). The use of systemic steroids lacks sufficient evidence at this time to recommend its routine use. Children may return to school after they have been on antibiotics for at least 24 hours and if they are afebrile and symptomatically improved.

Pearls and Pitfalls

1. Always consider serious and potentially life-threatening etiologies of sore throat
2. Always examine the patient
3. Listen to the parents
4. Use narrow spectrum antibiotics
5. Be sure the patient has outpatient follow-up and the parents know what symptoms require urgent re-evaluation

References

1. National Hospital Ambulatory Medical Care Survey: 2010 Emergency Department Summary Tables. http://www.cdc.gov/nchs/data/ahcd/nhamcs_emergency/2010_ed_web_tables.pdf. Accessed 8\31\2014.
2. Pfoh E, Wessels MR, Goldmann D, Lee GM: Burden and economic cost of group A streptococcal pharyngitis. Pediatrics 2008;121 (2):229-34.
3. Kaplan EL, Top FH, Dudding BA, et al: Diagnosis of streptococcal pharyngitis: Differentiation of active infection from the carrier state in the symptomatic child. J Infect Dis 1971;123:490-501.
4. Schwartz RH, Hayden GF, Wientzen R: Children less than three-year-old with pharyngitis: Are group A streptococci really that uncommon. Clin Pediatr 1986;25:185-8.
5. Wessels, MR: Streptococcal Pharyngitis. N Engl J Med 2011;364 (7):648-55.
6. Choby BA: Diagnosis and treatment of streptococcal pharyngitis. Am Fam Physician 2009;79(5):383-90.
7. Wolford RW: Evaluation of the sore throat. In: Diagnostic testing in Emergency Medicine. Wolfson AB and Paris PM, Editors. W. B. Saunders Company. 1996:159-71.
8. Bell AT, Fortune B: What test is the best for diagnosing infectious mononucleosis? J Fam Pract 2006;55(9):799-802.
9. Shulman ST, Bisno AL, Clegg HW, et al: Clinical practice guideline for the diagnosis and management of group A streptococcal pharyngitis: 2012 Update by the Infectious Diseases Society of America. CID 2012;55(10)e86-102.
10. Ebell MH, Smith MA, Barry HC, Ives B, Carey M: The rational clinical examination: Does this patient have strep throat? JAMA 2000;284:2912-8.
11. Funamura, JL, Berkowitz CD: Applicability of a scoring system in the diagnosis of streptococcal pharyngitis. Clin Pediatr 1983;22:622-6.
12. McIsaac WJ, White D, Tannenbaum D, Low DE: A clinical score to reduce unnecessary antibiotic use in patients with sore throat. Can Med Assoc J 1998;158(1)75-83.
13. Fine AM, Nizet V, Mandl KD: Large-scale validation of the Centor and McIsaac scores to predict group A streptococcal pharyngitis. Achr Intern Med 2012;172(11):847-52.
14. Hersh AL, Jackson MA, Hicks LA, and the Committee on Infectious Diseases: Principles of judicious antibiotic prescribing for upper respiratory tract infections in pediatrics. Pediatrics 2013;132:1146-54.
15. Snellman L, Adams W, Anderson G, Godfrey A, Gravley A, Johnson K, Marshall P, Myers C, Nesse R, Short S. Institute for Clinical Systems Improvement. Diagnosis and Treatment of Respiratory Illness in Children and Adults. http://bit.ly/RespIll. Updated January 2013.