Study of the Pathogenesis of Porphyria Cutanea Tarda
Primary Purpose
Porphyria Cutanea Tarda
Status
Completed
Phase
Locations
United States
Study Type
Observational
Intervention
Sponsored by
About this trial
This is an observational trial for Porphyria Cutanea Tarda focused on measuring inborn errors of metabolism, porphyria, porphyria cutanea tarda, rare disease
Eligibility Criteria
Well documented sporadic (Type I) or familial (Type II) porphyria cutanea tarda: Increased plasma porphyrins (fluorescence maximum at neutral pH near 617 nm) Increased urinary porphyrins (consisting mostly of uroporphyrin and heptacarboxylporphyrin) Increased isocoproporphyrins in feces No other type of porphyria
Sites / Locations
- University of Texas Medical Branch
Outcomes
Primary Outcome Measures
Secondary Outcome Measures
Full Information
NCT ID
NCT00005103
First Posted
April 6, 2000
Last Updated
June 23, 2005
Sponsor
National Center for Research Resources (NCRR)
Collaborators
University of Texas
1. Study Identification
Unique Protocol Identification Number
NCT00005103
Brief Title
Study of the Pathogenesis of Porphyria Cutanea Tarda
Study Type
Observational
2. Study Status
Record Verification Date
December 2003
Overall Recruitment Status
Completed
Study Start Date
November 2000 (undefined)
Primary Completion Date
undefined (undefined)
Study Completion Date
undefined (undefined)
3. Sponsor/Collaborators
Name of the Sponsor
National Center for Research Resources (NCRR)
Collaborators
University of Texas
4. Oversight
5. Study Description
Brief Summary
OBJECTIVES: I. Determine the effect of standard treatments on various predisposing factors in patients with porphyria cutanea tarda (PCT).
II. Investigate alcohol history, smoking, liver dysfunction and its etiology, estrogen use, and family history of PCT in these patients.
III. Study the relationships of excess iron and the hemochromatosis gene to PCT, including clinical features and risk of recurrence in these patients.
IV. Assess hepatitis C virus infections in these patients. V. Assess vitamin C levels in these patients before and after treatment. VI. Assess dietary habits in these patients. VII. Assess activity of cytochrome P450 enzymes (CYP) in vivo in these patients.
VIII. Study polymorphic genes for enzymes that metabolize foreign chemicals, including CYP enzymes and glutathione transferases in these patients.
Detailed Description
PROTOCOL OUTLINE: Patients undergo a complete medical evaluation and documentation of porphyria cutanea tarda (PCT) including history, physical examination, standard clinical laboratory tests and porphyrin studies. Alcohol history, smoking, liver dysfunction and its etiology, estrogen use, and family history of PCT are investigated and recorded. Patients complete a questionnaire to assess intake of vitamin C and other nutrients.
Iron status is assessed by serum ferritin, Fe and Fe binding capacity, and by the number of phlebotomies needed to reduce ferritin to the target level. A blood sample is tested for the hemochromatosis (HC) gene to determine whether each patient has 0, 1, or 2 copies of the HC mutation.
Serum hepatitis C virus (HCV) antibody and HCV RNA are measured. Standard liver function tests and liver biopsy are done if clinically indicated.
A fasting blood level of ascorbic acid is obtained. Blood clearance of caffeine and antipyrine, and urinary excretion of caffeine and chlorzoxazone metabolites are determined by breath tests or measurements in blood or saliva.
Genotyping for polymorphic genes for enzymes that metabolize foreign chemicals, including cytochrome P450 enzymes (CYP) and glutathione transferases are completed.
Following completion of the above studies, patients undergo individualized standard treatment either by serial phlebotomies or low dose chloroquine. Patients with HCV are also treated with interferon alfa-2b.
Patients are followed after treatment, at which time initial studies are repeated.
6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Porphyria Cutanea Tarda
Keywords
inborn errors of metabolism, porphyria, porphyria cutanea tarda, rare disease
7. Study Design
Enrollment
120 (false)
10. Eligibility
Sex
All
Minimum Age & Unit of Time
0 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Well documented sporadic (Type I) or familial (Type II) porphyria cutanea tarda: Increased plasma porphyrins (fluorescence maximum at neutral pH near 617 nm) Increased urinary porphyrins (consisting mostly of uroporphyrin and heptacarboxylporphyrin) Increased isocoproporphyrins in feces
No other type of porphyria
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Karl Elmo Anderson
Organizational Affiliation
University of Texas
Official's Role
Study Chair
Facility Information:
Facility Name
University of Texas Medical Branch
City
Galveston
State/Province
Texas
ZIP/Postal Code
77555-0209
Country
United States
12. IPD Sharing Statement
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Study of the Pathogenesis of Porphyria Cutanea Tarda
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