Differential Diagnosis for a Tender Lymph Node
Single Most Likely Diagnosis
- Viral Pharyngitis: This is often the most common cause of a tender lymph node, especially in the context of a recent upper respiratory infection. The lymph node tenderness is usually accompanied by other symptoms such as sore throat, fever, and fatigue.
Other Likely Diagnoses
- Bacterial Pharyngitis: Similar to viral pharyngitis but caused by bacterial pathogens like Streptococcus pyogenes. It presents with severe sore throat, fever, and tender lymph nodes.
- Cat Scratch Disease: Caused by Bartonella henselae, transmitted through cat scratches or bites. It leads to tender lymphadenopathy, usually in the axillary or neck region, depending on the site of the scratch.
- Infectious Mononucleosis: Caused by Epstein-Barr virus, it presents with fever, sore throat, fatigue, and tender lymph nodes, often in the cervical region.
Do Not Miss Diagnoses
- Lymphoma: Although less common, lymphoma can present with painless or tender lymphadenopathy. It's crucial to consider this diagnosis, especially in the absence of an obvious infectious cause or if the lymph node persists or grows over time.
- Tuberculosis: Can cause tender lymph nodes, especially in the cervical region, and is a critical diagnosis not to miss due to its public health implications and the need for specific treatment.
- Metastatic Cancer: In adults, especially those with a history of cancer, metastatic disease to the lymph nodes can cause tenderness and should be considered to ensure timely intervention.
Rare Diagnoses
- Kikuchi-Fujimoto Disease: A rare, self-limiting condition that causes tender lymphadenopathy, usually in the cervical region, accompanied by fever and night sweats.
- Castleman Disease: A rare disorder that involves an overgrowth of cells in the lymphatic system, which can cause tender lymph nodes among other symptoms.
- Kimura Disease: A rare, chronic inflammatory disorder that can cause tender lymphadenopathy, typically in the head or neck region, and is often associated with eosinophilia and IgE elevation.