Variegate Porphyria
Related Subjects:
|Acute Porphyrias
|Variegate Porphyria
|Acute Intermittent Porphyria (AIP)
|Porphyria Cutanea Tarda (PCT)
|Porphyria Testing
📖 About
- 🔬 Variegate Porphyria (VP) is caused by protoporphyrinogen oxidase deficiency.
- 🩺 It is one of the acute hepatic porphyrias, with both acute neurovisceral attacks and photosensitive skin changes.
🧬 Aetiology & Triggers
- 🌍 A hepatic porphyria, often familial.
- 💊 Precipitating factors include:
- ❌ Sulfonamides
- ❌ Oral contraceptives (OCPs)
- ❌ Barbiturates & anaesthetic agents
- 🍷 Alcohol
- ⚡ Fasting, stress, infection can also trigger attacks
🩺 Clinical Features
- ⚡ Acute attacks: severe abdominal pain, constipation, vomiting.
- 🧠 May also cause peripheral neuropathy, seizures, or psychiatric features (like AIP).
- ☀️ Fragile, blistering, photosensitive skin (distinguishes VP from AIP).
- 🔁 Recurrent attacks possible.
🔍 Investigations
- 🧪 ↑ Porphobilinogen (PBG) and Aminolevulinic Acid (ALA) in urine during attacks.
- 🍷 Urine darkens to port wine colour on standing.
- 💩 Faeces: ↑ coproporphyrins and ↑ protoporphyrins (key clue in VP).
- 💡 Plasma fluorescence emission peak at ~626 nm (UV light) is characteristic.
🤔 Differentials
- 🔴 Any acute abdomen (e.g. appendicitis, bowel obstruction, cholecystitis).
- 🧠 Other porphyrias (esp. AIP, HCP).
- Dermatological mimics: bullous pemphigoid, epidermolysis bullosa (for skin lesions).
🛠️ Management
- 📌 See Acute Porphyria management for detailed protocols.
- ☎️ Contact the National Acute Porphyria Service (NAPS, UK) for urgent advice.
- 🚫 Stop precipitating drugs and triggers immediately.
- 💉 IV glucose and haem arginate via NAPS if severe or prolonged attack.
- 🩺 Symptom control: opioids for pain, antiemetics, beta-blockers for tachycardia.
- ☀️ For skin lesions: strict sun avoidance, high-factor sunscreen, protective clothing.
📚 References
