FASAVA Congress 2017

Generalised weakness (tetraparesis) may be seen with diseases causing dysfunction of multiple peripheral motor nerves (polyneuropathy) and these diseases are frequently referred to as lower motor neuron (LMN) disease.  The clinical signs of polyneuropathy are indistinguishable from conditions primarily affecting the neuromuscular junction (junctionopathy) and often muscle (polymyopathy) and collectively these conditions are better termed motor unit disease.   
Peripheral neuropathies may result from disease processes affecting the motor neuronal cell bodies within the spinal cord, the spinal nerve roots, axons or terminal processes and may be acute in onset or more slowly progressive.  Clinically animals may present with weakness, a reduction or loss of muscle tone, decreased or absent spinal reflexes and early onset muscle atrophy. Cranial nerve involvement may be evident and facial muscle weakness, dysphagia, laryngeal paresis or obstruction and megaoesophagus are often seen.  
The causes of generalised peripheral neuropathy and junctionopathy are many and include toxicities, metabolic disturbances, immune mediated, degenerative and genetic causes. Early recognition and treatment is important and life saving for many. Time and nursing is required for others ,where recovery is likely, but may not occur for months and  other causes may be progressive despite any treatment.
The clinical presentation, approach to investigation and a discussion of the causes and treatment of polyneuropathies and junctionopathies will be discussed using case examples.