Porphyria Cutanea Tarda (PCT)

Etiology

  • A family of uncommon disorders associated w/abnormalities in heme biosynthesis in the liver
  • Dysfunctional or lower than normal levels of enzyme → accumulation of precursor proteins
  • Different symptoms/presentations based on which enzymes deficient → build up of different precursor proteins
  • Less likely to have family history than AIP (i.e. PCT is typically an acquired d/o)
  • PCT is the most common of the cutaneous porphyrias

Risk Factors

  • Hepatitis C in 2/3 of those w/PCT
  • Male predominance, age >40
  • Smoking, chronic alcohol use/cirrhosis, HIV, iron overload

Symptoms

  • Slow development of sometimes painful skin findings in sun exposed areas (e.g. hands, back of neck)
  • No neurological symptoms
  • Skin is easily damaged, peels, blisters w/minimal trauma
  • Excessive hair growth
  • Urine sometimes brown to reddish-brown

Physical Exam Findings

  • Excess hair growth on face/sun exposed areas
  • Blisters, pigmentation, fragile/slow healing skin in particular on back of hands

Tests