This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
ABSTRACT
Objectives: We conducted a systematic review of the literature with meta-analysis to determine whether complex regional pain syndrome (CRPS) is associated with a specific inflammatory profile and whether this is dependent on the duration of the condition.
Methods: Comprehensive searches of the literature using MEDLINE, Embase, Scopus, Web of Science, and reference lists from published reviews identified articles that measured inflammatory factors in CRPS. Two independent investigators screened titles and abstracts, and performed data extraction and risk of bias assessments. Studies were subgrouped by medium (blood, blister fluid, and CSF) and duration (acute and chronic CRPS). Where possible, meta-analyses of inflammatory factor concentrations were performed and pooled effect sizes were calculated using random-effects models.
Results: Twenty-two studies were included in the systematic review and 15 in the meta-analysis. In acute CRPS, the concentrations of interleukin (IL)-8 and soluble tumor necrosis factor receptors I (sTNF-RI) and II (sTNF-RII) were significantly increased in blood. In chronic CRPS, significant increases were found in 1) TNFα, bradykinin, sIL-1RI, IL-1Ra, IL-2, sIL-2Ra, IL-4, IL-7, interferon-γ, monocyte chemoattractant protein-1 (MCP-1), and sRAGE (soluble receptor for advanced glycation end products) in blood; 2) IL-1Ra, MCP-1, MIP-1β, and IL-6 in blister fluid; and 3) IL-1β and IL-6 in CSF. Chronic CRPS was also associated with significantly decreased 1) substance P, sE-selectin, sL-selectin, sP-selectin, and sGP130 in blood; and 2) soluble intercellular adhesion molecule-1 (sICAM-1) in CSF. Most studies failed to meet 3 or more of our quality criteria.
Conclusion: CRPS is associated with the presence of a proinflammatory state in the blood, blister fluid, and CSF. Different inflammatory profiles were found for acute and chronic cases.
GLOSSARY
- CI=
- confidence interval;
- CGRP=
- calcitonin gene-relaxed peptide;
- CRPS=
- complex regional pain syndrome;
- ET-1=
- endothelin-1;
- IL=
- interleukin;
- IP-10=
- interferon-inducible protein-10;
- MCP-1=
- monocyte chemoattractant protein-1;
- NPY=
- neuropeptide Y;
- PGE2=
- prostaglandin E2;
- SP=
- substance P;
- sTNF-R=
- soluble tumor necrosis factor receptor;
- TNF=
- tumor necrosis factor
Footnotes
Go to Neurology.org for full disclosures. Funding information and disclosures deemed relevant by the authors, if any, are provided at the end of the article.
Supplemental data at www.neurology.org
- Received May 16, 2012.
- Accepted August 9, 2012.
- © 2012 American Academy of Neurology
AAN Members: Sign in with your AAN member credentials (e-mail or 6-digit Member ID number)
Non-AAN Member subscribers: Sign in with subscriber credentials
Log in using your username and password
Purchase access
Disputes & Debates: Rapid online correspondence
NOTE: All authors' disclosures must be entered and current in our database before comments can be posted. Enter and update disclosures at http://submit.neurology.org. Exception: replies to comments concerning an article you originally authored do not require updated disclosures.
- Stay timely. Submit only on articles published within the last 8 weeks.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- 200 words maximum.
- 5 references maximum. Reference 1 must be the article on which you are commenting.
- 5 authors maximum. Exception: replies can include all original authors of the article.
- Submitted comments are subject to editing and editor review prior to posting.