Immune therapy for lumbosacral plexopathy (a condition that affects the network of nerves at the base of the spine) of unknown cause

Review question

Do treatments that act on the immune system have effects on idiopathic lumbosacral plexopathy (ILSP)?


ILSP is an uncommon disorder of the peripheral nerves and lumbosacral plexus that causes asymmetrical pain and weakness of the lower limbs. The lumbosacral plexus is a network of nerves near the base of the spine. This is where nerve fibres emerging from the spine as nerve roots reorganise themselves into peripheral nerves that extend into the legs. In ILSP, a process damages this nerve network, and changes in sensation can occur, such as tingling, and oversensitivity to touch. There may also be effects on the part of the nervous system that controls unconscious body functions (the autonomic nervous system). The cause or causes of ILSP are not clear, but it is thought that blood vessels become inflamed for reasons we do not yet know, and this reduces blood flow to the network of nerves. Some experts think that the reduced blood flow damages the nerves. It is possible that medication that reduces inflammation could be beneficial.


After a wide search for high quality studies of treatment (randomized controlled trials, or similar), we found no trials in ILSP of any form of therapy that acts on the immune system or reduces inflammation. There is presently no evidence from any trial to show whether immunotherapies help people with ILSP.

Database searches for this review were run on 15 October 2013.

Authors' conclusions: 

There is at present no evidence from randomized trials to support any recommendation on the use of any immunotherapy treatment in ILSP.

Read the full abstract...

Idiopathic lumbosacral plexopathy (ILSP), also called lumbosacral plexitis or non-diabetic lumbosacral (radiculo)plexus neuropathy is a rare clinical entity. The core features are (sub)acute, severe, asymmetrical leg pain, followed by asymmetrical multifocal weakness and atrophy in the subsequent weeks or months. Sensory symptoms include paresthesias, hypesthesia, allodynia, and autonomic dysfunction. ILSP generally runs a monophasic and self limiting course. Recovery starts slowly over months to several years and is nearly always incomplete. Some studies suggest that the condition has an immune-mediated etiology. Biopsies of distal cutaneous nerve segments have shown features suggestive of an inflammatory microvasculitis causing ischemic damage of the nerves. The clinical and pathological findings are similar to those found in diabetic lumbosacral plexus neuropathy and suggest that inflammation may form part of the final common pathway in both conditions.


To assess the effects of any form of immunotherapy in the treatment of ILSP.

Search strategy: 

On 15 October 2013, we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS, and Index to Theses. We scanned conference abstracts, and searched trials databases for ongoing trials. We checked all references in the identified trials and contacted authors to identify any additional published or unpublished data.

Selection criteria: 

We intended to include all randomized controlled trials (RCTs) or quasi-RCTs of any immunotherapy given within six weeks of disease onset, in participants with conditions fulfilling all the following: acute or subacute onset of pain and lower motor neuron weakness involving predominantly the proximal muscles of the lower limbs, weakness that is not confined to one nerve or nerve root distribution, electrophysiological tests showing predominantly axonal neuropathies, exclusion of other causes of lumbosacral radiculopathy and plexopathy as well as patients with plasma sugar in the diabetic range (fasting greater than 7.0 mmol/L, random greater than 11.1 mmol/L).

Data collection and analysis: 

Two authors independently examined all references retrieved by the search to select those meeting the inclusion criteria, according to standard Cochrane methodology.

Main results: 

We identified no RCTs of any immunotherapy for ILSP.