Ultrasonographic findings of jejunal lymph node lipomatosis in a cat: a case report

Objective: To report a case of lymph node lipomatosis (LNL) in a cat and describe its ultrasonographic characteristics.
Animal: A 16-year-old neutered female indoor European Shorthair cat.
Clinical Presentation: The cat was presented with a history of poor appetite. Clinical, laboratory, and imaging findings revealed chronic kidney disease. Abdominal ultrasound revealed jejunal lymph nodes (JLNs) that were non-enlarged and maintained a normal shape but appeared diffusely hyperechoic with a thin hypoechoic rim of uneven thickness. Power Doppler imaging revealed no detectable vascular signals in the JLNs. The differential diagnosis included lymph node lipomatosis based on human literature.
Outcome: The cat was euthanized two years later due to end-stage kidney disease. Ultrasound performed prior to euthanasia showed that the appearance of the JLNs remained unchanged. Histopathological examination of the jejunal lymph nodes confirmed adipocyte infiltration, replacing the lymphoid parenchyma and cortical thinning, consistent with LNL.
Clinical Relevance: To the best of our knowledge, this is the first documented case of LNL in a companion animal and the first description of its ultrasonographic features in veterinary medicine. This report introduces a new ultrasonographic pattern of lymph nodes and expands the list of differential diagnoses for lymphadenopathy in cats. Although further studies are needed, these findings provide valuable insights into a previously undescribed condition in cats.