Differential Diagnosis for a Swollen and Painful Lymph Node Under the Chin
Single Most Likely Diagnosis
- Viral Pharyngitis: This is the most common cause of a swollen and painful lymph node under the chin, often resulting from a viral infection such as the common cold or mononucleosis. The proximity of the lymph node to the throat makes it a likely site for reactive lymphadenopathy in response to a viral pharyngitis.
Other Likely Diagnoses
- Dental Infection: Infections of the teeth or gums can cause lymphadenopathy in the submandibular region due to the direct drainage of bacteria from the oral cavity to these lymph nodes.
- Bacterial Pharyngitis: Similar to viral pharyngitis, bacterial infections of the throat, such as streptococcal pharyngitis, can cause swollen and painful lymph nodes under the chin.
- Cat Scratch Disease: Caused by Bartonella henselae, this condition typically results from a cat scratch or bite and can lead to lymphadenopathy, often in the neck.
Do Not Miss Diagnoses
- Lymphoma: Although less common, lymphoma (both Hodgkin and non-Hodgkin) can present with lymphadenopathy and must be considered to avoid delayed diagnosis and treatment.
- Tuberculosis: TB can cause lymphadenitis, particularly in the cervical lymph nodes, and is crucial to diagnose due to its public health implications and the need for specific treatment.
- Metastatic Cancer: Cancer that has spread to the lymph nodes from a primary site, such as the oral cavity, thyroid, or skin, is a critical diagnosis not to miss due to its significant impact on treatment and prognosis.
Rare Diagnoses
- Sarcoidosis: A systemic granulomatous disease that can affect any organ, including the lymph nodes, leading to lymphadenopathy.
- Kikuchi-Fujimoto Disease: A rare, self-limiting condition that causes lymphadenitis, typically in the cervical region, and is more common in young women.
- Kimura Disease: A chronic inflammatory disorder that can cause lymphadenopathy and eosinophilia, more commonly seen in Asian males.