Lumbosacral plexitis—an overview
Lumbosacral plexitis is a rare neurological condition. In this disease, inflammation and swelling affect the region of the hip where the nerve roots emerging from the spinal cord crisscross and interconnect. One version occurs in diabetic patients (also known as diabetic amyotrophy) and another, rarer condition occurs in non-diabetic patients (also known as idiopathic lumbosacral plexitis). The disease begins with flu-like symptoms that are followed by excruciating proximal leg and hip pain, and then over a period of several weeks, by progressive weakness, sensory loss, and muscle atrophy. The disease may resolve itself spontaneously over several months, or can persist for years if left untreated. Current treatment includes a variety of immune-modulating therapies including IVIG, plasmapheresis, corticosteroids, and other drug regimens. The time course of recovery is quite prolonged, with many individuals not regaining full strength until 2 years or more after the initial onset of symptoms. Persistent weakness, atrophy, and sensory loss may still remain after treatment.
Developing an Animal Model of the Disease
The cause and progression of lumbosacral plexitis is very poorly understood, in part, due to the impracticality of obtaining pathology on human subjects. Past research involving biopsies of peripheral leg nerves (such as the intermediate cutaneous nerve of the thigh) have shown vasculitic type changes; however, it remains uncertain whether these findings are representative of the disease process affecting the plexus itself. Thus, with the support of a generous donor, we are in the process of developing a rodent model of the disease that will allow us to better study the disorder and evaluate potential treatments. Several different approaches to this study are planned, including the use of standard methods for inducing focal vasculopathy and by exposing the animal to plasma from humans with this disorder.
References:
Tarulli A, Rutkove SB. Lumbosacral plexitis. Clin Neuromuscular Disease. 2005;7:72-78
Weber M. Lumbosacral plexopathies. In: Brown WN, Bolton CF, Aminoff MJ, eds. Neuromuscular Function and Disease: Basic, Clinical, and Electrodiagnostic Aspects. Philadelphia: Saunders, 2002: 852-864.
Sander JE, Sharp FR. Lumbosacral plexus neuritis. Neurology 1981;31:470-473.
Evans BA, Stevens JC, Dyck PJ. Lumbosacral plexus neuropathy. Neurology 1981;31:1327-1330.
Dyck P, Norell J, Dyck P. Non-diabetic lumbosacral radiculoplexus neuropathy. Natural history, outcome, and comparison with the diabetic variety. Brain 2001;124:1197-1207.
Bradley WG, Chad D, Verghese JP. Painful lumbosacral plexopathy with elevated erythrocyte sedimentation rate: a treatable inflammatory syndrome. Ann Neurol 1984;15:457-464.
Suarez GA, Giannini C, Bosch EP, et al. Immune brachial plexus neuropathy: suggestive evidence for an inflammatory-immune pathogenesis. Neurology 1996;46:559-561.
Dyck PJB, Windebank AJ. Diabetic and nondiabetic lumbosacral radiculoplexus neuropathies: new insight into pathophysiology and treatment. Muscle Nerve 2002;25:477-491.
