Acute Porphyria Attack in Hematology

Acute porphyrias include acute intermittent porphyria, hereditary coproporphyria, variegate porphyria, and aminolevulinic acid dehydratase deficiency. Enzyme defects in heme biosynthesis lead to accumulation of porphyrin precursors aminolevulinic acid and porphobilinogen that cause neurovisceral toxicity during attacks triggered by drugs, fasting, hormones, infection, or alcohol.

Clinical attack manifests with severe diffuse abdominal pain without peritoneal signs, autonomic dysfunction with tachycardia and hypertension, motor neuropathy, hyponatremia from inappropriate antidiuretic hormone secretion, anxiety, confusion, hallucinations, and seizures. Diagnosis uses spot urine porphobilinogen quantitation during attack and DNA testing for definitive subtype confirmation.

Acute management uses intravenous hemin at three to four milligrams per kilogram daily for four days, high carbohydrate intake of three hundred grams per day, removal of triggers, pain control with safe opioids, beta blockers for autonomic instability, and seizure control with safe agents such as gabapentin avoiding barbiturates. Givosiran small interfering RNA reduces frequency of recurrent attacks in adult acute intermittent porphyria patients.