Health Dictionary Find a Doctor

Porphyria cutanea tarda

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Overview

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body’s organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Porphyria cutanea tarda from Other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications, and Prognosis

Diagnosis

Diagnostic Criteria

History and Symptoms

Physical Examination

Laboratory Findings

Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Prevention

References

Template:WS Template:WH

Historical Perspective

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Historical Perspective

References

Template:WS Template:WH

Classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Overview

Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body’s organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.

Classification

  • In the acquired form, the signs and symptoms of this condition are triggered by non genetic factors such as alcohol abuse, excess iron, certain hormones, and viral infections. However, in the inherited form of the disease, which affects up to 20% of PCT patients, the condition arises from a mutation in the uroporphyrinogen decarboxylase gene, although environmental and chemical factors may trigger or exacerbate symptoms.
  • Drug side effect: Chlorpropamide, Tolbutamide, Tolazamide

References

Template:WS Template:WH

Pathophysiology

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Pathophysiology

References

Template:WS Template:WH

Causes

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body’s organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.

Causes

  • In the acquired form, the signs and symptoms of this condition are triggered by non genetic factors such as alcohol abuse, excess iron, certain hormones, and viral infections. However, in the inherited form of the disease, which affects up to 20% of PCT patients, the condition arises from a mutation in the uroporphyrinogen decarboxylase gene, although environmental and chemical factors may trigger or exacerbate symptoms.
  • Drug side effect: Chlorpropamide, Tolbutamide, Tolazamide

Genetics

Inherited mutations in the UROD gene cause about 20 % of cases (the other 80 % of cases do not have mutations in UROD, and are classified as sporadic). UROD makes an enzyme called uroporphyrinogen III decarboxylase, which is critical to the chemical process that leads to heme production. The activity of this enzyme is usually reduced by 50 % in all tissues in people with the inherited form of the condition.

Nongenetic factors such as alcohol abuse, excess iron, and others listed above can increase the demand for heme and the enzymes required to make heme. The combination of this increased demand and reduced activity of uroporphyrinogen decarboxylase disrupts heme production and allows byproducts of the process to accumulate in the body, triggering the signs and symptoms of porphyria cutanea tarda.

The HFE gene makes a protein that helps cells regulate the absorption of iron from the digestive tract and into the cells of the body. Certain mutations in the HFE gene cause hemochromatosis (an iron overload disorder). People who have these mutations are also at an increased risk of developing porphyria cutanea tarda.

In the 20% of cases where porphyria cutanea tarda is inherited, it is inherited in an autosomal dominant pattern, which means one copy of the altered gene is sufficient to decrease enzyme activity and cause the signs and symptoms of the disorder.

20% of cases of porphyria cutanea tarda are inherited in an autosomal dominant pattern.


References

Template:WS Template:WH

Differentiating Porphyria cutanea tarda from other Diseases

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Differential Diagnosis

References

Template:WS Template:WH

Epidemiology and Demographics

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Porphyria cutanea tarda (PCT) is the most common subtype of porphyria. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body’s organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.

Epidemiology and Demographics

This type of porphyria occurs in an estimated 1 in 25,000 people, including both inherited and sporadic (noninherited) cases. An estimated 80 % of porphyria cutanea tarda cases are sporadic. The exact frequency is not clear because many people with the condition never experience symptoms.

References

Template:WS Template:WH

Risk Factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Risk Factors

References

Template:WS Template:WH

Screening

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Screening

References

Template:WS Template:WH

Natural History, Complications and Prognosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:

Please help WikiDoc by adding content here. It’s easy! Click here to learn about editing.

Overview

Natural History

Complications

Prognosis

References

Template:WS Template:WH

Diagnosis

Diagnosis

History and Symptoms | Physical Examination | Laboratory Findings | Electrocardiogram |X Ray | CT | MRI | Echocardiography or Ultrasound | Other Imaging Findings | Other Diagnostic Studies

Treatment

Treatment

Medical Therapy | Surgery | Primary Prevention | Secondary Prevention | Cost-Effectiveness of Therapy | Future or Investigational Therapies

Case Studies

Case Studies

Case #1

Template:WH Template:WS

Looking for the patient version?

Back to the patient-friendly article

© 2026 MyEClinic – IFTM Institut für Telematik in der Medizin GmbH