Diagnosis and Treatment of Acute Exudative Tonsillitis
Use the Centor criteria to risk-stratify patients with acute exudative tonsillitis, perform rapid antigen detection testing (RADT) for those with 3-4 criteria, and treat only confirmed Group A streptococcal infections with penicillin V 500 mg orally twice daily (or 250 mg three times daily) for 10 days. 1, 2
Risk Stratification Using Centor Criteria
The clinical presentation described—sore throat, fever, tonsillar exudates, and tender anterior cervical lymphadenopathy—represents 4 out of 4 Centor criteria (assuming absence of cough), placing this patient in the highest risk category for Group A streptococcal (GAS) infection with a 32-56% probability. 1, 2
The four Centor criteria are:
- Fever by history (≥38.3°C or 101°F) 1, 2
- Tonsillar exudates 1
- Tender anterior cervical lymphadenopathy 2
- Absence of cough 1, 2
Diagnostic Testing Strategy
For patients with 3-4 Centor criteria, perform RADT immediately. 1 The test has high specificity (>95%) and sensitivity (≥90%), making it reliable for point-of-care diagnosis. 1
If RADT is positive: Treat with antibiotics immediately without need for throat culture confirmation. 1
If RADT is negative: The Infectious Diseases Society of America recommends confirming with throat culture before initiating antibiotic therapy, though some guidelines suggest no further testing is needed given the high negative predictive value (93-97%). 3, 1
For patients with 0-2 Centor criteria: Do not perform testing and do not prescribe antibiotics, as the likelihood of GAS is low and most cases are viral. 1
First-Line Antibiotic Treatment
Penicillin V remains the drug of choice for confirmed GAS pharyngitis:
- Dosing: 500 mg orally twice daily OR 250 mg three times daily for 10 days 3, 2, 4
- Duration: A full 10-day course is necessary to maximize bacterial eradication and prevent rheumatic fever 4, 5
- Alternative: Amoxicillin 500 mg twice daily for 10 days is equally effective 4
For penicillin-allergic patients:
- First-generation cephalosporins (if no history of anaphylaxis) 4
- Macrolides: azithromycin, clarithromycin, or erythromycin 3, 4
- Clindamycin for severe penicillin allergy 4
Symptomatic Management for All Patients
Regardless of etiology, provide symptomatic relief:
- Ibuprofen or acetaminophen (paracetamol) for pain and fever 1, 2
- Throat lozenges may provide additional comfort 2
- Adequate hydration 6
Counsel patients that typical sore throat duration is less than 1 week, with most cases resolving within 7 days. 2 Even with confirmed streptococcal infection, antibiotics provide modest symptom relief, shortening sore throat duration by only 1-2 days (number needed to treat = 6 at 3 days). 2
Critical Pitfalls to Avoid
Do not treat based on clinical appearance alone. Physicians overdiagnose streptococcal pharyngitis by 80-95%, leading to unnecessary antibiotic use. 7, 8 The presence of exudates does not confirm bacterial infection—many viral infections (particularly Epstein-Barr virus, adenovirus) cause exudative pharyngitis. 3, 5
Do not prescribe antibiotics for patients with 0-2 Centor criteria. This leads to antimicrobial resistance, unnecessary side effects, and costs without meaningful benefit. 1
Distinguish chronic GAS carriers from acute infection. Carriers (up to 20% of school-aged children) have positive tests but are experiencing viral pharyngitis. 1 Clues suggesting carriage rather than acute infection include: recent antibiotic treatment, viral symptoms (cough, coryza, conjunctivitis, diarrhea), and persistence of the same GAS strain over multiple episodes. 3
When to Consider Alternative Diagnoses
Viral features suggesting non-streptococcal etiology:
- Conjunctivitis, cough, hoarseness, coryza 3
- Discrete ulcerative lesions, viral exanthem 3
- Diarrhea 3, 5
- Generalized lymphadenopathy and splenomegaly (suggesting infectious mononucleosis) 3
Other bacterial causes to consider:
- Neisseria gonorrhoeae in sexually active individuals 3
- Arcanobacterium haemolyticum (often with scarlatiniform rash in teenagers/young adults) 3
- Fusobacterium necrophorum (Lemierre syndrome) in severe cases with unilateral symptoms 3
Management of Treatment Failures
If symptoms persist or recur shortly after completing appropriate therapy:
- Consider chronic GAS carriage with concurrent viral infection 3
- For documented treatment failures, use agents with higher eradication rates: clindamycin, amoxicillin-clavulanate, or first-generation cephalosporins 3, 8
- Intramuscular benzathine penicillin G eliminates compliance issues 3, 8
Do not routinely obtain post-treatment cultures unless the patient remains symptomatic or special circumstances exist (outbreak situations, personal/family history of rheumatic fever). 3