Case Study: A 48-year-old male presents with blisters and sores on his dorsal hands. The patient is a former intravenous drug abuser and carries a diagnosis of hepatitis C virus infection, which has been untreated to date. He reports moderate alcohol consumption, but otherwise states he uses no illicit substances and takes no medications. He notes the lesions are generally asymptomatic, though the erosions are tender.
- Review of systems is otherwise unremarkable; the patient is currently afebrile, and denies night sweats, cough, chills, unintentional weight loss, or gastrointestinal complaints.
- Physical exam reveals diffuse hyperpigmentation and hirsutism. There are no lesions in skin overlying the genitalia, axillae, nipples, or trunk.
This patient has classic features of porphyria cutanea tarda (PCT), with flaccid, easily ruptured bullae with resulting erosions, signs of skin fragility, and some scarring. He also has diffuse hyperpigmentation and increased hair growth, both commonly seen in PCT. PCT is due to abnormal uroporphyrinogen decarboxylase, which can be inherited or acquired; most cases are acquired. Causes of PCT include hemochromatosis, alcohol, hepatitis, or other sources of liver injury. The diagnosis can be confirmed by visualizing fluorescence of urine under Wood’s lamp examination, or through formally measuring the urinary porphyrin levels. Uroporphyrinogen decarboxylase activity can be measured as well. Patients should be evaluated for diseases which can affect the liver, including, potentially, hemochromatosis (HFE gene testing is widely available). Treatments include sun avoidance (as patients are often photosensitive), treatment of underlying liver disease, and prevention of further liver damage (i.e. alcohol avoidance). Smoking may worsen the disease, and patients should receive tobacco cessation counseling and assistance. Iron stores may be reduced by therapeutic phlebotomy. Some patients benefit from antimalarial therapy, particularly if they cannot undergo or tolerate phlebotomy.
Management & Therapy Tips
- Porphyria cutanea tarda can present with photosensitivity, hyperpigmentation, hypertrichosis, and skin fragility manifesting as flaccid, fragile bullae, shallow erosions, and small scars on the dorsal hands
- PCT is due to underlying uroporphyrinogen decarboxylase deficiency, often due to underlying liver disease
- Patients should be screened for causes of liver disease and avoid further hepatotoxic agents
- Management includes sun protection, avoiding liver toxicity, and smoking cessation
- Phlebotomy may be used to lower total iron stores
- Antimalarial drugs may help patients who cannot tolerate phlebotomy or in whom phlebotomy is contraindicated