A history of throat pain and fever

CASE

A 16-year-old female presented to the emergency department (ED) with a 3-day history of sore throat, fever, and malaise. She had discomfort in swallowing solid foods but was able to tolerate fluids. According to the patient, a number of her friends had recently been diagnosed with “strep throat.”

History The patient's immunizations were up-to-date, and the medical history was significant only for asthma. The patient had no recent illness prior to the current symptoms. She denied cough, rhinorrhea, headache, abdominal pain, skin rashes, or excessive fatigue.

Physical examination The patient appeared comfortable and nontoxic. Initial vital signs were BP, 105/81 mm Hg; pulse, 129 beats per minute; respirations, 16 breaths per minute; oral temperature, 100.9°F; and oxygenation, 100% on room air by pulse oximetry. She had a slightly muffled voice and bilateral pharyngeal erythema, 2+ edema, and white-colored exudates (see Figure 1). The uvula was midline, and no intraoral petechiae were noted. Cervical lymph nodes were slightly enlarged, moderately tender, and most prominent in the anterior cervical regions. The lungs were clear, and there was no abdominal tenderness or palpable hepatosplenomegaly. Laboratory tests revealed that the WBC count was 8,700/µL with 21% lymphocytes and 9% variant lymphocytes. A rapid strep test and mononucleosis spot test (monospot) were also performed.

WHAT IS YOUR DIAGNOSIS?

• Streptococcal pharyngitis
• Diphtheria
• Infectious mononucleosis
• Peritonsillar abscess

DISCUSSION

Results were positive on both the rapid strep antigen test and the monospot test, suggesting that the patient had both streptococcal pharyngitis and infectious mononucleosis. Infection with group A beta-hemolytic streptococci (GABHS) causes 15% to 30% of pharyngitis cases in children and up to 10% of cases in adults.^1,2 Mononucleosis, most often caused by Epstein-Barr virus (EBV), is most common in children and young adults and accounts for 1% to 2% of cases of pharyngitis.¹ Coinfection with EBV and GABHS was documented in studies performed nearly 30 years ago. Some of these older studies estimated coinfection rates ranging from 3% to 33%.² A more recent retrospective study suggested a GABHS coinfection rate of up to 20.7% in children with confirmed EBV infection.² However, throat cultures and rapid strep testing cannot reliably differentiate an active strep infection from an asymptomatic carrier state.¹ Therefore, the actual prevalence of coinfection is somewhat unclear and likely lower than estimated.

Treatment This patient was started on antibiotics and fluids in the ED. She was discharged on a course of antibiotics for streptococcal pharyngitis and given supportive therapy and educational resources for the infectious mononucleosis. A follow-up phone call was made 10 days after presentation. The patient's symptoms improved within a few days of presentation, and her sore throat and fevers eventually resolved.

Comment Sore throat is one of the most common complaints in primary and urgent care. Most cases are caused by viruses.¹ Antibiotics are rarely indicated and should be reserved for cases of confirmed bacterial infection, such as with GABHS.^1,3 Appropriate antibiotic prescribing can be guided by pharyngitis clinical decision rules, such as the Centor criteria. Most rules stratify patients by clinical characteristics such as the presence of fever, lymphadenopathy, or tonsillar exudates and absence of cough.³ Various treatments can help to ease symptoms, including salt-water gargles, anesthetic lozenges, and acetaminophen or NSAIDs.^1,4 Single-dose dexamethasone has also been shown to reduce the pain and duration of symptoms, especially in cases of moderate to severe pharyngitis.⁴

Although it is relatively rare, coinfection should be considered when treating a patient with pharyngitis. Knowing about a coinfection can affect treatment decisions—for example, ampicillin or amoxicillin should be avoided in a patient with infectious mononucleosis because of the associated rash that can occur. In cases of suspected streptococcal pharyngitis, clinical decision rules and rapid strep and mononucleosis testing can aid treatment decisions and help to sort out the sometimes cloudy clinical picture of pharyngitis. JAAPA

Erich Fogg, PA-C, MMSc, department editor

REFERENCES