​Dermatology - Porphyria Cutanea Tarda

​Dermatology - Porphyria Cutanea Tarda
Porphyria cutanea tarda primarily affects adults and, in contrast to other forms of porphyria, does not present with acute life-threatening episodes. The onset often manifests between the ages of 30 and 50, with rare occurrences in youngsters. Women who are taking oral contraceptives and men who are undergoing estrogen therapy for prostate cancer have an increased risk.
Substances that can trigger porphyria cutanea tarda include ethanol, estrogen, hexachlorobenzene, chlorinated phenols, iron, and tetrachlorodibenzo-p-dioxin. Administration of high dosages of chloroquine might result in the development of clinical symptoms in individuals with "latent" instances, although modest doses are typically employed for therapeutic purposes.
Additional factors that increase the likelihood of a condition include diabetes mellitus (25%), hepatitis C virus, and hemochromatosis.

Patients do not exhibit a typical sensitivity to light, but instead report having "fragile skin," blisters, and large blisters, especially on the back of the hands, following small injuries.
Abnormalities
The central facial skin gradually develops a purple-red discoloration, along with brown hypermelanosis, excessive hair growth (hypertrichosis), and scleroderma-like alterations and scars in exposed places. The presence of tense bullae and erosions on skin that seems normal gradually undergoes healing, resulting in the formation of pink atrophic scars. Additionally, milia measuring 1-2 mm can be observed on the dorsa of the hands and feet, as well as on the nose, forehead, or bald scalp.

The diagnosis is established through clinical assessment and verified by the detection of a pinkish-red fluorescence in the urine upon examination with a Wood lamp. The differential diagnosis comprises pseudoporphyria, chronic renal failure requiring hemodialysis, and epidermolysis bullosa acquisita.


Advise the patient to abstain from consuming ethanol, discontinue any medications that may trigger porphyria cutanea tarda (PCT), and prevent contact with chemicals such as chlorinated phenols and tetrachlorodibenzo-p-dioxin. Perform phlebotomy every one to two weeks for a duration of 5 to 12 months to extract 500 mL of blood and initiate remission. The occurrence of relapse within a year is infrequent, ranging from 5% to 10%. Low-dose chloroquine can achieve remission in individuals who are unable to undergo recurrent phlebotomies due to anemia. However, it should only be administered by a physician who has expertise in treating PCT.