Pharyngitis for NP
Pharyngitis for the Nurse Practitioner Licensing Exam
Etiology
- Viral Causes:
- The majority of pharyngitis cases are viral, especially in adults. Common viral pathogens include:
- Rhinovirus: The most common viral cause.
- Adenovirus: Associated with sore throat, conjunctivitis, and fever (pharyngoconjunctival fever).
- Epstein-Barr Virus (EBV): Causes infectious mononucleosis with fever, posterior cervical lymphadenopathy, and fatigue.
- Influenza and Parainfluenza: Pharyngitis along with systemic symptoms like fever, myalgias, and cough.
- Bacterial Causes:
- Group A Streptococcus (GAS) (Streptococcus pyogenes) is the most common bacterial cause, responsible for up to 30% of pharyngitis cases in children and 5-15% in adults.
Clinical Features
- Viral Pharyngitis:
- Sore throat accompanied by cough, rhinorrhea, and hoarseness. Often mild and self-limiting.
- EBV-associated pharyngitis presents with posterior cervical lymphadenopathy, fatigue, and splenomegaly.
- Bacterial Pharyngitis (GAS):
- Sudden onset of sore throat, fever, tonsillar exudates, and tender anterior cervical lymphadenopathy. Absence of cough is typical.
Diagnosis
- Centor Criteria:
- Assesses the likelihood of GAS pharyngitis:
- Tonsillar exudates (+1)
- Tender anterior cervical lymphadenopathy (+1)
- Fever (+1)
- Absence of cough (+1)
- A Centor score of ≥3 warrants further testing (e.g., RADT or throat culture).
- Rapid Antigen Detection Test (RADT):
- Confirms GAS infection. A negative result in children should be followed by a throat culture.
Management
- Viral Pharyngitis:
- Treatment is supportive:
- Analgesics (e.g., acetaminophen, ibuprofen) for pain and fever.
- Hydration, throat lozenges, and rest. Antibiotics are not indicated.
- Bacterial Pharyngitis (GAS):
- Antibiotics are necessary to prevent complications:
- First-line: Penicillin V or amoxicillin.
- For penicillin-allergic patients: Clindamycin, cephalexin, or azithromycin.
Complications
- Suppurative:
- Peritonsillar abscess: Severe sore throat, trismus, "hot potato" voice. Requires drainage and antibiotics.
- Nonsuppurative:
- Rheumatic fever and post-streptococcal glomerulonephritis can occur after untreated GAS pharyngitis.
Key Points
- Viral infections are the most common cause of pharyngitis, while Group A Streptococcus (GAS) is the main bacterial cause.
- Diagnosis of GAS pharyngitis is guided by the Centor criteria, confirmed with rapid antigen detection tests (RADT) or throat cultures.
- Viral pharyngitis is managed with supportive care, while bacterial (GAS) pharyngitis requires antibiotics to prevent complications like rheumatic fever.
- Complications include peritonsillar abscess, rheumatic fever, and post-streptococcal glomerulonephritis.