Hereditary angio-oedema with C1 inhibitor deficiency type I, an unusual stroke mimic

Hereditary angio-oedema with C1 inhibitor deficiency (C1-INH-HAE) type I is a rare immune disorder characterised by a deficit of functional C1 esterase inhibitor (C1-INH). Recurrent C1-INH-HAE attacks typically present as generalised skin swelling and abdominal pain. Neurological involvement is very unusual, with a few reports of cephalea and recurrent dizziness. We describe a woman in her 30s diagnosed with C1-INH-HAE type I who was referred to the emergency department suffering from left hemisensory syndrome, with the initial suspicion of an ischaemic stroke. A few hours after hospital admission, she presented an acute attack of facial swelling and abdominal pain, receiving intravenous C1-INH concentrate with complete resolution of all symptoms, including neurological ones. A complete aetiological study ruled out a stroke. We pointed out that C1-INH-HAE attack can be an unusual stroke mimic that responds favourably to replacement therapy.