Strep Throat: Symptoms, Diagnosis, and Treatment

What Is Strep Throat?

Streptococcal pharyngitis caused by Streptococcus pyogenes (Group A Strep). Bacterial, not viral.

Classic Symptoms

• Sudden severe sore throat.
• Fever (>38.3°C / 101°F).
• Tonsillar exudates (white patches).
• Tender anterior cervical lymphadenopathy.
• Absence of cough, rhinorrhea, hoarseness (suggests viral).

Diagnosis

• Rapid Antigen Detection Test (RADT): Minutes, high specificity, lower sensitivity.
• Throat Culture: Gold standard (24–48 hrs).
• Centor/McIsaac Criteria: Clinical scoring to guide testing.

Treatment

• Penicillin/Amoxicillin: 10 days (first-line, narrow spectrum, no resistance).
• Alternatives for allergy: Cephalexin, azithromycin, clindamycin.
• Symptomatic: Analgesics, hydration, soft foods.

Why Treat?

• Shorten symptoms by ~1 day.
• Prevent suppurative complications (peritonsillar abscess, sinusitis).
• Prevent non-suppurative sequelae: Acute rheumatic fever (ARF), post-strep glomerulonephritis (PSGN).
• Reduce transmission.

Return to School/Work

After 24 hrs on antibiotics and afebrile.