Evidence map›Paper›PMID 42466614›Full record

ArticlePain practice : the official journal of World Institute of Pain2026

Elevated Serum Soluble CD163 Indicates Macrophage Activation: A Potential Biomarker for Inflammation in Complex Regional Pain Syndrome?

Nadia Kriek, Krishna Bharwani, Maaike Dirckx, Dirk Stronks, Nicole Nagtzaam, Wim A Dik, Frank Huygen

Abstract read
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Article in Pain practice : the official journal of World Institute of Pain, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Nadia KriekCenter for Pain Medicine, Department of Anesthesiology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.ORCID https://orcid.org/0000-0002-0276-1511
Krishna BharwaniCenter for Pain Medicine, Department of Anesthesiology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.ORCID https://orcid.org/0000-0003-4899-0624
Maaike DirckxCenter for Pain Medicine, Department of Anesthesiology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.ORCID https://orcid.org/0000-0002-4306-654X
Dirk StronksCenter for Pain Medicine, Department of Anesthesiology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.
Nicole NagtzaamLaboratory Medical Immunology, Department of Immunology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.
Wim A DikLaboratory Medical Immunology, Department of Immunology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.ORCID https://orcid.org/0000-0001-5235-3156
Frank HuygenCenter for Pain Medicine, Department of Anesthesiology, Erasmus MC University Medical Center, Rotterdam, the Netherlands.ORCID https://orcid.org/0000-0002-2852-4880

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSeveral studies point towards the involvement of the immune system (especially the monocyte-macrophage system) in the pathophysiology of Complex Regional Pain Syndrome (CRPS), as shown by increased levels of the cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6. These cytokines are primarily released from pro-inflammatory M1 macrophages, but are difficult to measure in a clinical setting. Investigating the activity of tissue-resident macrophages by measuring soluble CD163 (sCD163) in serum is much more clinically applicable. sCD163 could potentially be a biomarker for determining inflammation in CRPS and would have direct consequences for the choice of therapy. The aim of this study is to investigate the tissue-resident macrophage activation in CRPS with sCD163 and explore the relationship between soluble IL-2R, which is a marker for T-cell activation, and sCD163.

methodsThe sCD163 levels were determined in this retrospective cohort study (MEC-2020-0716) in serum of CRPS patients (n = 22) and healthy controls (n = 27). ELISA kits were used to measure the levels of these markers. Data on demographics, pain scores (11-point Numeric Rating Scale: NRS), sIL-2R levels, signs and symptoms, and CRPS disease severity were also recorded.

resultsThe median serum sCD163 level was significantly higher in CRPS patients (CRPS 960.5 pg/mL [Q3-Q1: 1211.5-623.9] than in healthy controls 677.0 pg/mL [Q3-Q1: 828.0-469.5], p = 0.008). There was a statistically significant positive correlation between sCD163 and sIL-2R in the CRPS group (r

conclusionOur findings indicate that pro-inflammatory activation of tissue-resident macrophages and thus the monocyte-macrophage system is part of CRPS pathogenesis. The monocyte-macrophage system is an interesting new target for future research into the pathogenesis of CRPS, but also has potential for diagnosis, particularly for assessing the involvement of the immune system and choice of therapy in the individual CRPS patient. Measurement of the sCD163 could be a potential biomarker for inflammation in CRPS.

trial registrationThis retrospective cohort study was approved by the Medical Ethics Committee of the Erasmus MC University Medical Center (MEC-2020-0716).

Indexed as

Antigens, CDAntigens, Differentiation, MyelomonocyticComplex Regional Pain SyndromesInflammationMacrophage ActivationReceptors, Cell SurfaceAdultAgedBiomarkersCD163 AntigenCohort StudiesFemaleHumansMaleMiddle AgedRetrospective StudiesAntigens, CDAntigens, Differentiation, MyelomonocyticBiomarkersCD163 AntigenReceptors, Cell Surface

Identifiers

PMID42466614
PMCPMC13377953

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.