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Study of Proteins Associated With Complex Regional Pain Syndrome

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00033969
Recruitment Status : Terminated
First Posted : April 18, 2002
Last Update Posted : December 12, 2019
Information provided by:
National Institutes of Health Clinical Center (CC)

Brief Summary:

This study will try to learn more about complex regional pain syndrome, or CRPS (previously known as reflex sympathetic dystrophy, spreading neuralgia, and sympathalgia), by examining the release of small proteins in the blood of patients with this condition. Patients with CRPS usually have three types of symptoms:

  • Sensory abnormalities increased sensitivity to pain or a painful reaction to a harmless stimulus
  • Perfusion abnormalities alterations in blood flow, temperature abnormality, swelling, decrease or increased nail growth, and hair and skin changes
  • Motor abnormalities weakness, guarding (Holding the limb in such a fashion that it minimizes accidental or intentional contact from possible sources of pain), and atrophy (wasting)

The cause of CRPS is unknown, and there are no definitive diagnostic tests for the condition. Because early treatment improves the prognosis of CRPS, a test that enables early diagnosis would be important for optimal medical management. The findings of this study may contribute to the development of such a test and possibly new drug treatments.

Normal healthy volunteers and patients of any age with complex regional pain syndrome who are in otherwise good general health may be eligible for this study.

Participants will have a medical history, physical examination and collection of a blood sample. They will fill out several questionnaires, providing information on their health, personality, mood, pain levels, and symptoms. Participation in the study requires one outpatient clinic visit.

Condition or disease
Complex Regional Pain Syndromes Healthy

Detailed Description:

The etiology of Complex Regional Pain Syndrome (CRPS) is unknown but a patient typically presents with a triad of clinical findings: sensory abnormalities, perfusion abnormalities and alterations in motor function. Since some of these findings are seen in the other disease states, the diagnosis is often not clear. A response to a sympathetic ganglion block (stellate or lumbar) is also suggestive of the disorder. However, there is no definitive diagnostic test for CRPS. Experience has shown that early aggressive treatment improves the prognosis. Therefore, tests that facilitate the early diagnosis would have important clinical implications.

Advances in laboratory techniques allow analysis of clinical samples to identify protein or patterns of protein changes associated with a disease state. Patients suffering with CRPS who are currently seen in a pain clinic will be asked to participate in this study. The subjects will complete a brief symptom survey, be examined by a co-investigator to document sensory, temperature and trophic changes, and have a blood sample collected for protein and gene expression (RNA) analysis. Blood samples from age-matched controls will be collected from non-CRPS patients. Fifty patient samples collected from each group will be analyzed and used to teach the diagnostic software and an additional 20 samples (10 controls, 10 CRPS patients) will be used to validate diagnostic accuracy.

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Study Type : Observational
Actual Enrollment : 120 participants
Official Title: Complex Regional Pain Syndrome Proteomics Study
Study Start Date : April 15, 2002
Study Completion Date : October 23, 2014

Resource links provided by the National Library of Medicine

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years and older   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
  • Male or female patients referred by their physician with the diagnosis of CRPS criteria as outlined by Stanton-Hicks et al.


  • Healthy volunteers will be screened according to the eligibility criteria as specified in the appendix (see Healthy Subject Eligibility).
  • Age restrictions: Patients and volunteers must be (Bullet)18 years of age at the time of enrollment. There is no upper limit for age of inclusion.
  • Good general health (other disease states could may confound the results see exclusion criteria)
  • Willing to have blood drawn
  • Willing to have behavioral measures
  • Willing to provide a directed medical history
  • There is expected to be a greater number of females than males being recruited to this study since there is a much higher occurrence of CRPS in women. Additionally, it is expected to be equal across all ethnic groups. However, we do not anticipate requiring any special recruiting strategies for specific gender or ethnic groups.


  • Contraindication to blood screening
  • Advanced disease other than the CRPS (cardiovascular, liver, kidney disease ASA III or above excluding CRPS) that may cause a theoretical inclusion of samples resulting in confounding results.
  • Pregnant and lactating women.

No exclusions will be made based on race, gender, or religion.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00033969

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United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institute of Nursing Research (NINR)
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Principal Investigator: Andrew J Mannes, M.D. National Institutes of Health Clinical Center (CC)
Layout table for additonal information Identifier: NCT00033969    
Other Study ID Numbers: 020169
First Posted: April 18, 2002    Key Record Dates
Last Update Posted: December 12, 2019
Last Verified: October 23, 2014
Keywords provided by National Institutes of Health Clinical Center (CC):
Chronic Pain
Neuropathic Pain
Normal Control
Complex Regional Pain Syndrome
Healthy Volunteer
Additional relevant MeSH terms:
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Complex Regional Pain Syndromes
Reflex Sympathetic Dystrophy
Somatoform Disorders
Pathologic Processes
Mental Disorders
Autonomic Nervous System Diseases
Nervous System Diseases
Peripheral Nervous System Diseases
Neuromuscular Diseases