Streptococcal Pharyngitis
Streptococcal Pharyngitis
- Most cases of pharyngitis: Viral
- Most cases of bacterial pharyngitis: Group A beta-hemolytic streptococcus
- Incidence: 15-30% (children) and 5-20% (adults)
- Peak season: late winter/ early spring
- Transmission: respiratory secretions
- Incubation period: 24-72 hours
- Antibiotics shorten symptoms by 16 hours
Modified Centor Scoring
| Criteria | Points |
|---|---|
| Absence of cough | 1 |
| Swollen and tender cervical nodes | 1 |
| Temp >100.4F (38C) | 1 |
| Tonsillar exudates or swelling | 1 |
| Patient age: | |
| 3-14 yr | 1 |
| 15-44 yr | 0 |
| ≥ 45 yr | -1 |
| Score | Incidence of GABHS | Plan |
|---|---|---|
| ≤0 | 1-2.5% | No testing, no antibiotics |
| 1 | 5-10% | No testing, no antibiotics |
| 2 | 11-17% | Do rapid antigen test |
| 3 | 28-35% | Do rapid antigen test |
| ≥4 | 51-53% | No testing, empiric antibiotics |
National Organization Guidelines
How to screen for strep pharyngitis
| Group | Recommendations |
|---|---|
| ACP/CDC/AAFP | Use Centor criteria to decide testing and antibiotics |
| AAP | Use clinical & epidemiological findings to assess risk for GABHS (includes Centor scores) |
| IDSA | Use clinical & epidemiological findings to assess risk for GABHS (includes Centor scores) |
Diagnostic Test
| Group | Recommendations |
|---|---|
| ACP/CDC/AAFP | Rapid antigen test only for Centor scores of 2 or 3 only |
| AAP | Rapid antigen test or throat culture for ALL patients at risk |
| IDSA | Rapid antigen test or throat culture for ALL patients at risk |
Backup culture needed if rapid Ag test is negative?
| Group | Recommendations |
|---|---|
| ACP/CDC/AAFP | Adults: No; Pediatrics: Yes |
| AAP | Adults: N/A; Pediatrics: Yes |
| IDSA | Adults: No; Pediatrics: Yes |
Who gets antibiotics?
| Group | Recommendations |
|---|---|
| ACP/CDC/AAFP | Empiric abx for Centor score of ≥ 4, or those with positive rapid antigen test result |
| AAP | Positive rapid antigen test or throat culture |
| IDSA | Positive rapid antigen test or throat culture |
Which antibiotic?
| Group | Recommendations |
|---|---|
| ACP/CDC/AAFP | Oral penicillin V, IM penicillin G benzathine, or oral amoxacillin |
| AAP | Oral penicillin V, IM penicillin G benzathine, or oral amoxacillin |
| IDSA | Oral penicillin V, IM penicillin G benzathine, or oral amoxacillin |
Which antibiotic for PCN allergy?
| Group | Recommendations |
|---|---|
| ACP/CDC/AAFP | Oral erythromycin, or first-gen cephalosporin |
| AAP | Oral erythromycin, or first-gen cephalosporin |
| IDSA | Oral erythromycin, or first-gen cephalosporin |
- ACP = American College of Physicians
- CDC = Center for Disease Control
- AAFP = American Academy of Family Physicians
- AAP = American Academy of Pediatrics
- IDSA = Infectious Disease Society of America
References
- Choby BA.Diagnosis and treatment of streptococcal pharyngitis.Am Fam Physician. 2009 Mar 1;79(5):383-90. [PubMed]
