Acute Intermittent Prophyria Mimicking Pheochromocytoma

Lee, Byoung Kwon; Bae, Hee Dong; Park, Hyo Jin; Jung, Jun Keun; Chung, Jun Pyo; Lee, Kwan Sik; Lee, Sang In; Park, In Suh

Abstract

Acute intermittent porphyrla(AIP) is a disorder that results frorn partial deficiency of porpbobi- linogen dearninase an has varlable clinical manifestations, such as acute abdominal pain, vomiting, nausea, constipation, perlpheral neuropathy, seizure, abnormal psychic symptoms, respiratory failure, tachycardia, and hypertension. If cases present severe acute hypertension, their clinical signs may mimick pheochromocytoma and the diagnosis of AIP would be delayed. We experienced a case of acute intermittent porphyria presenting with acute hypertension, mimicking pheochromo- cytoma in a 35 year-old female patient. She had history of two admissions to different hospitals with acute hypertension and abdominal pain. An extensive investigations had been done but no specific diagnosis was made. She had previously responded well to atenolol but after continuous treatement this led to hypotention. Her blood pressure was 210/140mmHg in both arms at admision to this hospital. She complained of acute abdominal pain and constipation, and she also had psychotic episodes. She had intermittent severe hypertension with the feature of pheochro- mocytorna. Tests for pheochromocytoma(including 24h urinary catecholamines, clonidine-inhibition test) were negative. Apart from slightly increased urinary excretion of catecholamines on one occasion, her symptoms were provoked by starvation and emotional stress and neurologic exami- nation revealed peripheral neuopathy. A screening test for porphobilinogen was strongly positive, but tests for uroporphyrin and coproporphyrin were negative. AIP was confirmed by clinical features and increased 24 hour urine delta-aminolevulinic acid(60.2 mg/1). Also, screening test for porphobilinogen was strongly positive in her mother and her brother. Supportive treatment with high glucose solution infusion and cimetidine resulted in symptomatic recovery and she was discharged after being educated on precipitating factors. The presenting feature of acute hypertension in this case baffled several doctors and the diagnosis of AIP was long delayed. AIP should be considered as one of the differential diagnosis of acute hypertension, especially when pheochrornocytoma is suspected but cannot be demonstrated.