1. A 10-year-old boy presents with high fever, sore throat, and difficulty swallowing for 4 days. His tonsils are inflamed and enlarged with white membranes.
2. Differential diagnoses include membranous tonsillitis, diphtheria, infectious mononucleosis, leukemia, and peritonsillar abscess.
3. Membranous tonsillitis is caused by pyogenic organisms forming an exudative membrane over the tonsils. Diphtheria and infectious mononucleosis can also present with white membranes over the tonsils.