A mother brings her nine year-old daughter to the pediatrician’s office with complaints of sore throat, fever, and malaise for 2 days. The girl has not had cough or runny nose. The mother is concerned about strep throat because a classmate of the daughter’s was just diagnosed with this. On exam, the girl has erythematous tonsillar pillars, palatal petechiae, and impressive cervical lymphadenopathy (Figure 29-1). A throat swab for rapid streptococcal antigen is positive and the girl is treated with penicillin VK for 10 days and recovers completely.

Upper respiratory tract infection (URI), also known as the common cold, and pharyngitis, inflammation and pain of the pharyngeal tissues, including the pharynx, tonsils and adenoids are among the most common illnesses of childhood. URIs are characterized by rhinorrhea, nasal congestion, and sore or scratchy throat. They are caused by viruses. Symptoms and signs of pharyngitis include throat soreness or scratchiness, fever, headache, malaise, rash, joint and muscle pains, and cervical lymphadenopathy. Viruses are responsible for the majority of cases of pharyngitis in infants and children, although Group A β-hemolytic streptococci (GABHS) are important causes of pharyngitis because of their ability to cause suppurative (peritonsillar and parapharyngeal abscesses) and non-suppurative (acute rheumatic fever and glomerulonephritis) complications.

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  Acute URI and pharyngitis account for 3.4 percent and 1 percent of primary care visits, respectively.¹

  
  
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  Viral infections account for the vast majority of cases of URI and 60 to 90 percent of cases of pharyngitis in children. GABHS is responsible for the majority of bacterial pharyngitis.

  
  
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  In temperate climates, the highest prevalence of URI and pharyngitis occurs from autumn until spring. This corresponds directly with circulating viruses over this period of time.

  
  
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  Frequency of URIs varies with age: highest frequency is in children 1 to 5 years of age, who experience 7 to 8 colds per year; infants less than one year of age average 6.5 colds a year; adolescents average 4.5 colds per year.²

  
  
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  Highest incidence of GABHS pharyngitis is in school-aged children and adolescents.

  
  
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  Acute rheumatic fever is rare in the US (see Chapter 45, Acute Rheumatic Fever).

  
  
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  Viruses causing URIs and pharyngitis can be spread via small particle aerosol (Influenza and Coronaviruses), large particle droplet (Rhinoviruses), or direct hand-to-hand transmission (Rhinoviruses and RSV).

  
  
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  Up to 14 percent of deep neck infections result from pharyngitis.³

Anatomy

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  The lingual tonsils on the base of tongue, the lateral palatine tonsils (“tonsils”) and the superior pharyngeal tonsils (“adenoids”) together make up Waldeyer’s ring. This ring of lymphoid tissue is favorably located for airborne and food-related antigen exposure.

  
  
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  Adenoids and tonsils are predominantly B-cell organs and immunologically most active between the ages of 4 and 10 years.^4,5 Overall, data show that adenotonsillectomy does not significantly affect the immune system adversely.

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  Rhinoviruses are the most common cause of URIs and pharyngitis in children; other viruses implicated include coronaviruses, respiratory syncytial virus (RSV), human metapneumovirus, influenza virus, parainfluenza viruses, adenovirus, enteroviruses (i.e., herpangina), and human bocavirus.⁶

  
  
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  Herpes simplex virus, human immunodeficiency virus, syphilis, and Neisseria gonorrhoeae are causes of pharyngitis in sexually active adolescents.

  
  
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  Viruses that infect nasal epithelial cells release cytokines and other inflammatory mediators, producing an inflammatory response of polymorphonuclear cells such as albumin and bradykinins that are responsible for the clinical symptoms of URI.

  
  
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  The paranasal sinuses and middle ear are commonly involved during uncomplicated URIs. Thus, it is common to have abnormal CT and MRI scans of the sinuses and middle ear fluid during URIs.^7,8

  
  
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  Some viruses, such as adenovirus, cause inflammation of the pharyngeal mucosa by direct invasion of the mucosa or secondary to suprapharyngeal secretions.⁹ Other viruses, such as rhinovirus, cause pain through stimulation of pain nerve endings by mediators, such as bradykinin.

  
  
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  GABHS accounts for 15 to 30 percent of pharyngitis cases in children and up to 38 percent of cases of tonsillitis.

  
  
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  GABHS releases exotoxins and proteases. Erythrogenic exotoxins are responsible for the development of the scarlatiniform exanthem (Figure 29-2).¹⁰

  
  
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  Secondary cross-reacting antibody formation during GABHS pharyngitis can result in rheumatic fever and valvular heart disease.¹¹ Antigen–antibody complexes can lead to acute poststreptococcal glomerulonephritis. These are the nonsuppurative complications of GABHS infection.

  
  
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  GABHS pharyngitis can result in suppurative complications including bacteremia, otitis media, meningitis, mastoiditis, cervical lymphadenitis, endocarditis, pneumonia, or deep neck abscess formation (Figure 29-3).

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  Immune deficiency.

Clinical Features

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  Infants and young children with URI commonly manifest fever, nasal congestion, irritability, and rhinorrhea, which may be clear or purulent. Mild to moderate enlargement of the anterior cervical lymph nodes may be present.

  
  
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  Older children and adolescents commonly manifest rhinorrhea, sore or scratchy throat, sneezing, sinus fullness, malaise, and hoarseness. Physical exam findings are minimal and may include mild erythema of the pharyngeal or nasal mucosa.

  
  
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  Rapid onset of odynophagia, tonsillar exudates, anterior cervical lymphadenopathy, and fever are consistent with streptococcal pharyngitis. Headache and abdominal pain are common in children who have streptococcal pharyngitis.

  
  
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  Not all tonsillar exudates are caused by streptococcal pharyngitis. Mononucleosis and other viral causes of pharyngitis commonly produce tonsillar exudates in children (Figures 29-4 and 29-5). The positive predictive value for tonsillar exudate in strep throat is only 31 percent; that is, 69 percent of patients with tonsillar exudate will have a nonstreptococcal cause.

  
  
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  Para- and supratonsillar edema with medial and/or anterior displacement of the involved tonsil and uvular displacement to the contralateral side suggest peritonsillar abscess (Figure 29-2). Trismus and anterior cervical lymphadenopathy with severe tenderness to palpation are additional findings.

  
  
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  Palatal petechiae can be seen in all types of pharyngitis (Figures 29-1 and 29-6).

  
  
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  A sandpaper rash is suggestive of scarlet fever (Figure 29-2, and Chapter 28, Scarlet Fever and Strawberry Tongue). Strawberry tongue frequently accompanies scarlet fever (Figure 28-4).

  
  
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  Lymphoid hyperplasia from viral infections, gastroesophageal reflux disease (GERD), or allergies can cause a cobblestone pattern on the posterior pharynx or palate (Figure 29-7). Although it usually is more suggestive of a viral infection or allergic rhinitis, lymphoid hyperplasia can be seen in strep pharyngitis (Figure 29-8).

  
  
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  The presence of rhinorrhea and nasal congestion indicate a viral URI infection and are not consistent with GABHS infection.