If a patient has a very swollen uvula and tonsils almost touching it, what is the most likely cause?

The presence of a very swollen uvula and tonsils almost touching it is most suggestive of a viral infection, especially when considering common presentations such as infectious mononucleosis, which is often caused by the Epstein-Barr virus. Viral infections commonly lead to inflammation and edema of the tonsils and uvula due to the body’s immunological response to the viral antigens.

While bacterial infections can also cause tonsillar enlargement, the nature of the swelling is often accompanied by other systemic signs such as fever and lymphadenopathy variable in severity. Key features like exudative tonsillitis may be present, but the pattern of swelling with the uvula reflects a tendency seen more often in viral cases. Allergic reactions can cause swelling, but they typically affect the soft tissues more diffusely and may not result in such pronounced enlargement of the tonsils specifically. Cancerous growth tends to present more insidiously, often with other symptoms and findings on examination that align differently, such as lesions or signs of unintentional weight loss. Thus, viral infection is the most fitting cause of the clinical scenario described.