Scientists at the University of Liverpool have discovered that treating the immune system of patients with Complex Regional Pain Syndrome (CPRS) leads to a significant reduction in pain.
CRPS is an unexplained chronic pain condition that usually develops after an injury or trauma to a limb, and continues after the injury has healed. CPRS I - formerly called Reflex Sympathetic Dystrophy - can arise after any type of injury. CRPS II, previously called causalgia (a term coined in the American Civil War when it was first diagnosed), follows partial damage to a nerve. In some cases the pain can be so severe that patients request amputation, only to find that the pain returns in the stump.
CRPS pain can improve within one year after the injury, but if it is still unchanged after 12 months (longstanding CRPS), then it will often not improve at all. Longstanding CRPS affects about 1 in 5,000 people in the UK.
The team at the Pain Research Institute discovered that a single, low dose infusion of intravenous immunoglobin (IVIG) significantly reduced pain in just under 50 per cent of patients treated, with few adverse effects. The pain relief lasted on average 5 weeks. The results of this study may change the future treatment of patients with CRPS, and have an impact on research in other severe chronic pain areas. Intravenous immunoglobulin treatment for CRPS is currently not available on the NHS.
Although the cause of the syndrome is unknown, precipitating factors include injury or damage to the body's tissue. Changes in the way nerves send messages to the brain about pain may occur at the injury site. These changes may then lead to more changes in the nerves of the spinal chord and brain. All these changes are thought to play a role in causing and prolonging the condition. Conventional pain drugs either don't work, or have considerable side effects.
Dr Goebel, Senior Lecturer in Pain Medicine, explains: "In CRPS, the real effect of this treatment in clinic may turn out to be even greater than what we have already seen, because IVIG can be given in higher doses, and repeated treatment may have additional effects. IVIG is normally repeated every four weeks and we are working to develop ways which would allow patients to administer the treatment in their own home."
"The discovery is expected to have a real impact on the treatment of other unexplained chronic pain conditions; if one pain condition can be effectively treated with an immune drug, then it is possible that other types will also respond."
The research is published in the journal Annals of Internal Medicine.
Notes to editors:
1. Danielle Brown took up archery in 2003 because the CRPS in her feet meant that she had to give up sports that she had previously participated in, such as fell running. She wasn't aware of paralympic sport in general but thought that archery would be her best option as it didn't involve running or walking very far which caused her a lot of pain.
Danielle won a gold medal at the Paralympic Games in Beijing in 2008 and gold medals in both the team and individual events at the 2009 World Championships. In addition to this, she also holds 10 world records. Danielle is available to talk to the press on Thursday, 28 January 2010 between 2 and 4pm and on Friday, 29 January, between 2 and 4pm. If you wish to speak to Danielle please contact Sarah stamper on 0151 794 3044.
2. The research was carried out in collaboration with University College London.
3. Research activities on the role of the immune system in chronic pain are the focus of the newly created 'Centre for Immune Studies in Pain' (CISP) at the University of Liverpool, led by Dr. Goebel. For further details visit www.liv.ac.ukpricisp. Support for these and other research activities aimed at relieving chronic pain comes from the Pain Relief Foundation in Liverpool, www.painrelieffoundation.org.uk.
4. An embargo-copy of the article can be obtained from Angela Collom at the American College of Physicians, phone: 001 215 351 2653; e-mail: firstname.lastname@example.org
5. The University of Liverpool is a member of the Russell Group of leading research-intensive institutions in the UK. It attracts collaborative and contract research commissions from a wide range of national and international organisations valued at more than £97 million annually.