Porphyria Cutanea Tarda

Condition Name: Porphyria Cutanea Tarda (PCT)

Definition: PCT is a disorder characterized by blistering lesions on sun-exposed skin due to a deficiency of the enzyme uroporphyrinogen decarboxylase (UROD).

Etiology: PCT can be inherited or acquired. Acquired PCT is often linked to liver disease, such as hepatitis C, alcohol abuse, or hemochromatosis, while familial PCT involves a genetic mutation in the UROD gene.

Epidemiology: PCT is the most common type of porphyria, typically presenting in adults in their 40s or 50s. Familial cases tend to present earlier in life, while sporadic cases often appear in the fourth or fifth decades.

Signs: Blistering, fragile skin on sun-exposed areas like the hands and face, with potential hyperpigmentation, scarring, and milia.

Symptoms: Skin sensitivity to sunlight, pain and discomfort in affected areas, and dark urine due to elevated porphyrins.

Differentials: Variegate porphyria, bullous pemphigoid, lupus erythematosus.

Diagnosis: Confirmed through porphyrin level testing in blood, urine, and stool, with a Wood’s lamp examination revealing fluorescence in urine.

Treatment: Therapeutic phlebotomy to reduce iron levels, low-dose antimalarials like hydroxychloroquine, and strict sun protection.

References:

1.     Singal AK. Porphyria cutanea tarda: Recent update. Mol Genet Metab. 2019;128(3):271-281. doi:10.1016/j.ymgme.2019.01.004

2.     Frank J, Poblete-Gutiérrez P. Porphyria cutanea tarda–when skin meets liver. Best Pract Res Clin Gastroenterol. 2010;24(5):735-745. doi:10.1016/j.bpg.2010.07.002