Local cytokine changes in complex regional pain syndrome type I (CRPS I) resolve after 6 months

• Published in: Pain (Amsterdam) Vol. 154; no. 10; pp. 2142 - 2149
• Main Authors: LENZ, Melanie, ÜCEYLER, Nurcan, TEGENTHOFF, Martin, MAIER, Christoph, FRETTLÖH, Jule, HÖFFKEN, Oliver, KRUMOVA, Elena K, LISSEK, Silke, REINERSMANN, Annika, SOMMER, Claudia, STUDE, Philipp, WAAGA-GASSER, Ana M
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Elsevier 01.10.2013
• Subjects: Adult; Aged; Biological and medical sciences; Biomarkers - blood; Cytokines - blood; Female; Fundamental and applied biological sciences. Psychology; Humans; Male; Medical sciences; Middle Aged; Nervous system involvement in other diseases. Miscellaneous; Neurology; Pain Measurement - methods; Pain Measurement - trends; Prospective Studies; Reflex Sympathetic Dystrophy - blood; Reflex Sympathetic Dystrophy - diagnosis; Reflex Sympathetic Dystrophy - epidemiology; Somesthesis and somesthetic pathways (proprioception, exteroception, nociception); interoception; electrolocation. Sensory receptors; Time Factors; Vertebrates: nervous system and sense organs; Treatment; Reeducation; Cytokine concentrations; Complex regional pain syndrome; Cytokine; Inflammation; Local inflammation; Rehabilitation; Neuropathic pain
• ISSN: 0304-3959; 1872-6623
• DOI: 10.1016/j.pain.2013.06.039

There is evidence that inflammatory processes are involved in at least the early phase of complex regional pain syndrome (CRPS). We compared a panel of pro- and antiinflammatory cytokines in skin blister fluids and serum from patients with CRPS and patients with upper-limb pain of other origin (non-CRPS) in the early stage (< 1 year) and after 6 months of pain treatment. Blister fluid was collected from the affected and contralateral nonaffected side. We used a multiplex-10 bead array cytokine assay and Luminex technology to measure protein concentrations of the cytokines interleukin-1 receptor antagonist (IL-1RA), IL-2, IL-6, IL-8, IL-10, IL-12p40, and tumor necrosis factor-alpha (TNF-α) and the chemokines eotaxin, monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1β (MIP-1β). We found bilaterally increased proinflammatory TNF-α and MIP-1β and decreased antiinflammatory IL-1RA protein levels in CRPS patients compared to non-CRPS patients. Neither group showed side differences. After 6 months under analgesic treatment, protein levels of all measured cytokines in CRPS patients, except for IL-6, significantly changed bilaterally to the level of non-CRPS patients. These changes were not related to treatment outcome. In serum, only IL-8, TNF-α, eotaxin, MCP-1, and MIP-1β were detectable without intergroup differences. Blister fluid of CRPS patients showed a bilateral proinflammatory cytokine profile. This profile seems to be relevant only at the early stage of CRPS. Almost all measured cytokine levels were comparable to those of non-CRPS patients after 6 months of analgesic treatment and were not related to treatment outcome.