Plexiform vascularization of lymph nodes: an unusual but distinctive lymphadenopathy in cats.

A distinctive lymphadenopathy in nine cats, four of which were of the Longhair breed, was characterized by capillary vasoproliferation and lymphoid atrophy. It occurred in the cervical or inguinal regions. The animals were, apart from local manifestations, healthy at the time and remained so subsequently. In the absence of any clinical or morphological evidence for viral, neoplastic or developmental aetiologies, we postulate an ischaemic pathogenesis for the lesions which may be related to human "vascular transformation of lymph node sinuses". The lesions appear to be by no means a rare cause of non-neoplastic lymphadenopathy in domestic cats, since they constituted over 5 per cent of surgical biopsies of cat lymph nodes seen in the past 5 years. The lesions merit wider recognition and investigation.