Making the Diagnosis
To accurately assess and diagnose this patient’s condition, the clinician needs to consider conditions that would cause exudative pharyngitis. The main 2 considerations with tonsillar exudate are group A streptococcal pharyngitis (strep throat) and mononucleosis from Epstein-Barr virus (EBV). Group B and C streptococcal infections typically are found in vaginal flora but can also cause exudative pharyngitis. Gonorrhea, meningococcus, and fusobacteria are less common potential causes of exudative pharyngitis.
Palatal petechiae are most suggestive of streptococcal pharyngitis but may also indicate mononucleosis, rubella, roseola, palatal trauma, and hemorrhagic fevers. With fever, exudate, and palate findings, strep throat would be the most likely diagnosis but mononucleosis is still a possibility. At this point, either testing or empiric antibiotics would be a reasonable next step.
Strep throat is the most common cause of exudative pharyngitis. The typical presentation is fever, sore throat, absence of cough, and tonsillar exudate, also known as the Centor criteria. Approximately 80% of cases of strep throat occur in patients between the ages of 5 and 15 years. Additional or atypical findings may include enlarged tonsils, palatal petechiae, headache, abdominal pain, and rash from scarlet fever. Most of these atypical findings are reported to be more common in patients younger than 8 years. These younger patients are less likely to form tonsillar exudates and may only have tonsillitis.
Testing recommendations vary by organization or publication but many emergency medicine experts recommend avoiding testing when 3 to 4 of the Centor criteria are present; save testing for unclear cases or treatment failures. Some people are colonized by group A strep and, thus, false positive cultures can occur. Other diagnoses to consider include mononucleosis, which usually requires no treatment other than avoiding contact sports; gonorrhea, which may require additional antibiotics; and group B or C strep, which typically responds to usual strep throat antibiotic choices.
Treatment for strep throat is usually a 10-day course of penicillin or amoxicillin. Cephalexin, however, may be better tolerated and have fewer treatment failures. For patients with unreliable pharmacy access, intramuscular penicillin G benzathine-penicillin G procaine may be given. For patients with severe beta-lactam allergies, clindamycin is a good option as well as azithromycin, cefadroxil, cephalexin, or clarithromycin. Although macrolides may be effective, drug-resistance rates are high with these agents.
Complications of strep throat are rare but can include peritonsillar abscess, glomerulonephritis, and rheumatic fever. Because strep throat is contagious, patients should avoid school or work until they have completed at least 24 to 48 hours of antibiotic treatment.
A strep culture was taken in the ED and was positive. The patient improved on a course of antibiotics.
Brady Pregerson, MD, is an emergency physician at Tri-City Medical Center, Palomar Health System, and Scripps Coastal Urgent Care, all in San Diego, California.
Pregerson DB. ENT chapter. Emergency Medicine 1-Minute Consult. 5th ed. 2017;5. http://www.erpocketbooks.com/emergency_medicine_reference_books/quick-essentials-emergency-medicine/