Differential Diagnosis for Slough on Tonsils with Negative Strep Test

• Single most likely diagnosis:
  • Mononucleosis (Infectious Mononucleosis): This condition, caused by Epstein-Barr virus (EBV), often presents with exudative tonsillitis, which can appear as slough on the tonsils. The negative strep test helps to rule out streptococcal pharyngitis, making mononucleosis a leading consideration.
• Other Likely diagnoses:
  • Viral pharyngitis: Other viruses such as adenovirus, herpes simplex virus, and enteroviruses can cause similar symptoms, including tonsillar exudates or slough.
  • Mycoplasma pneumoniae infection: This atypical bacterial infection can present with pharyngitis and tonsillar exudates, although it's more commonly associated with lower respiratory symptoms.
• Do Not Miss diagnoses:
  • Diphtheria: Although rare in areas with high vaccination coverage, diphtheria is a potentially life-threatening condition that can cause a membrane or slough on the tonsils. It's crucial to consider this diagnosis, especially in unvaccinated or under-vaccinated individuals.
  • Lemierre's syndrome: This condition, characterized by a bacterial infection (often Fusobacterium necrophorum) of the tonsils and subsequent septic thrombophlebitis of the internal jugular vein, can present with severe pharyngitis and tonsillar exudates. It's a medical emergency due to the risk of sepsis and embolic events.
• Rare diagnoses:
  • Tonsillar tuberculosis: In areas where tuberculosis is prevalent, it can manifest as chronic tonsillitis with caseous necrosis appearing as slough on the tonsils.
  • Tonsillar carcinoma: Although extremely rare, especially in younger populations, malignancies of the tonsils can present with asymmetric tonsillar enlargement and necrotic areas that might be mistaken for slough.
  • Histoplasmosis or other fungal infections: In immunocompromised patients, fungal infections can cause oral and pharyngeal lesions, including those resembling slough on the tonsils.