PetMD highlights differential diagnosis for swollen lymph nodes in cats

PetMD has published a new clinical explainer on swollen lymph nodes in cats, framing feline lymphadenopathy primarily as a sign of immune activation rather than a diagnosis itself. The article, written by Rhiannon Koehler, DVM, says enlarged nodes are most often tied to infection or inflammation, with neoplasia a less common but important differential, and highlights common triggers including FeLV, FIV, dental disease, and recent vaccination. It also emphasizes that while most cases aren't immediate emergencies, unexplained lymph node enlargement should still prompt a veterinary exam, especially if it appears alongside lethargy, reduced appetite, or breathing difficulty. (petmd.com)

Why it matters: For veterinary professionals, the piece is a timely pet parent-facing reminder that palpable lymph node changes can reflect a wide differential, from reactive hyperplasia and localized oral disease to systemic infectious disease and lymphoma. That matters in practice because peripheral lymphadenopathy is less common in cats than in dogs, and workups may need to move beyond observation to cytology, retroviral testing, imaging, or infectious disease testing depending on signalment and concurrent signs. Cornell notes that peripheral-node presentations are comparatively uncommon in feline lymphoma, while Merck’s veterinary guidance identifies lymphadenopathy as a feature that can occur in acute FeLV infection, reinforcing the need for a careful, structured diagnostic approach. (vet.cornell.edu)

What to watch: Expect continued emphasis on triaging which cats can be monitored briefly, such as some recently vaccinated or otherwise explainable cases, versus which should move quickly to aspiration, biopsy, or broader systemic workup. (petmd.com)