Evaluation of Five Selected Markers in Skin Biopsies of Patients With Postherpetic Neuralgia and Healthy Controls

Study Overview
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Brief Summary
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Postherpetic Neuralgia is a painful nerve condition that can occur when nerve fibers are damaged following an outbreak of shingles. The purpose of this study is to identify and study abnormalities in the nerves and cells in the of patients with postherpetic Neuralgia (PHN) and characterize changes that could be responsible for causing nerve pain. This data will be compared to the tissue of healthy volunteers. Our goal is that this information will lead to the development of better treatment options for people with painful nerve conditions.

Official Title
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Immunolabeling Evaluation of Five Selected Markers in Skin Biopsies of Patients With Postherpetic Neuralgia (PHN) and Age and Gender-Matched Normal Controls

Conditions
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Postherpetic Neuralgia, Healthy Age/Gender Matched Volunteers

Intervention / Treatment
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* Other: skin biopsy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Group 1: 5 Caucasian males >50 years of age with PHN of greater than 6 months duration since rash healed and clinically meaningful pain (Visual Analog Scale (VAS) >40mm at Baseline) Group 2: 5 Caucasian males >50 years of age, non-diabetic with no nervous system disease (healthy control groups) Exclusion Criteria: History of clinically significant liver disease, serious peripheral vascular disease, a blood clotting disorder, or any other medical condition felt to be exclusionary by the investigator Allergy to lidocaine Unwillingness to sign informed consent or any other reasons for which the investigator feels the subject cannot complete the study History of slow-healing diabetic foot ulcers HgA1c >11% within the last three months Active cancer within the previous two years, except treated basal cell carcinoma of the skin Co-morbidities that can produce neuropathy Subjects taking sodium channel blockers within one week of study treatment and throughout the study Subjects taking any other experimental drugs within 30 days prior to enrollment Application of lidocaine patch to either foot or to PHN site within two weeks of enrollment

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 95 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: skin biopsy|Using a punch biopsy, the study doctor will take a small sample of skin (3mm diameter) from a pre-defined site of the subject. For PHN patients, 4 biopsies will be obtained: 2 in an area of PHN and 2 in a contralateral control site. Biopsy sites for each PHN control subject will be matched anatomically to the corresponding PHN patient with two biopsies each from symmetrical sites in a left and right dermatome. One biopsy from each site in each subject will be fixed in a left and right dermatome. One biopsy from each site in each subject will fixed yb immersion in 4% paraformaldehyde for immunocytochemical analysis, and the second biopsy form each site will be flash frozen for assessments of mRNA expression.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| use of genetic data to enhance the search for targeted therapeutic approaches to chronic pain management | The skin biopsies will be used to identify the site of expression of selected makers in skin, including nerve fibers and skin substructures in patients with PHN and age and gender-atched normal controls. | One year |