GROUP-A BETA HEMOLYTIC STREP (GABHS) PHARYNGITIS

Photo Credit: Dr. James Heilman from Wikipedia

PHARYNGITIS

: MC caused (30-60%) by viral infection in adults – rhinovirus

: caused by bacterial infection in adults in only in 5-10% - GABHS

: accounts for 30-40% of case in children

: prevents rheumatic fever – by starting antibiotics 10 days after onset of symptoms

: SORE THROAT from Epstein-Barr virus (82%) – found in pxs with Infectious Mononucleosis –

• Tx mostly consist of

1. Supportive care

2. Rest

3. Antipyretics

4. Analgesics

 

GABHS-PHARYNGITIS

: MC pathogen responsible for most case of bacterial pharyingitis – BUT accounts only 10% of adult cases

            : Symptoms – usually rapid onset:

- Severe sore throat

- Odynophagia

- Cervical lymphadenopathy

- Fever

- Chills

- Malaise

- Headache

- Mild neck stiffness

- Anorexia

: Symptoms usually NOT PRESENT:

-      Trismus, hoarseness, cough, conjunctivitis, diarrhea, rhinorrhea, discrete ulcerative lesions

: OTHER accompanying symptoms:

- Erythema

- Edema

- Gray-white exudates symmetrically inv. affected tissues

: Symptoms MAY BE present:

- Petechiae on soft palate

- Swollen tonsils

- Characteristic foul breath

 

: IF UNTREATED – usually self-limited and resolves about 3-7 days

: prevention of rheumatic fever – possible if antibiotic started up to 10 days

: DIFFICULT TO DIAGNOSE – scoring systems developed

1.     Walsh & colleagues

: 5 ITEMS:

1) Enlarged or tender cervical lymph nodes

2) Pharyngeal exudates

3) Recent exposure to GABHS

4) Recent cough

5) Oral temp – greater than 38.3 deg Celsius

2.     Centor & coworkers

: 4 VARIABLE ADDITIVE SCORE –

- 3 OR 4 the criteria = 40-60% positive predictive value

- ABSENCE of 3 or 4 criteria = 80 negative predictive value

- endorsed by Centers for Disease and Prevention (CDC), American Academy of Family Physicians and American College of Physicians

1) Hx of fever

2) Anterior cervical lymphadenopathy

3) Tonsillar exudates

4) Absence of cough to

: SHOULD NOT BE USED in:

-  Immunocompromised

- Have complicated comorbidities

- Have history of rheumatic fever

: Diagnosis by THROAT CULTURE in a SHEEP-BLOOD AGAR PLATE – Infectious Disease Society of America (IDSA) recommended GOLD STANDARD for documentation

-       Use of RAPID ANTIGEN TEST alone w/o throat culture  - acceptable alternative

: TREATMENT of CHOICE – Penicillin or Amoxicillin for 10 days (and all antibiotic choices) except when Azithromycin is used (5-day course)

-       ALTERNATIVES:

1)  Single Dose IM injection of Benzathine Penicillin

2) Erythromycin – for pxs allergic to penicillin

3) Clindamycin – acceptable for patients with both penicillin allergy and strain resistant to macrolide

: on FOLLOWUP: - retesting is not recommended

-       Clindamycin or Co-Amoxiclav recommended for multiple, repeated, symptomatic episodes or laboratory-proven GABHS

-       TONSILLECTOMY considered when symptomatic recurrent episodes do not decrease in frequency despite appropriate microbial therapy