Reactive Node Diseases

Introduction

Some diseases can target the lymph nodes and they become actively involved in the disease process, and these are listed below according to their causal organism and presenting symptoms. The lymph node is also a suitable place to biopsy when looking for evidence of other systemic diseases which can be diagnosed by locating evidence of them in the node using immunological laboratory techniques. These include Canine Distemper Virus, Classical Swine Fever, Bovine East Coast Fever and Canine Leishmaniasis.

Diseases Involving Both Reactive Nodes and Lymphadenitis

viz. brucellosis and Johne's disease

• chronicity is caused by persistence of intacellular bacteria in lymph node macrophages
• Type IV hypersensitivity, but does not result in visible necrosis as in TB

Equine strangles

• acute inflammation
• produce pyogenic or necrotic foci in the drainage nodes
• involves submaxillary nodes

Streptococcal adenitis or head gland disease

• dogs
• acute inflammation as in above