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Is AIP the missing piece in your diagnosis?
Acute porphyrias often remain undiagnosed for more than a decade after first symptoms develop.1
Porphobilinogen (PBG) urine test
A urine test for PBG should be used to confirm a diagnosis of AIP in a symptomatic patient.2
- The test must be ordered at or near the time of acute symptoms.
- Urinary PBG level is markedly increased during acute attacks of AIP.
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Second‑line testing
If a patient’s PBG level is increased, additional tests should be done. Laboratory findings that can confirm the diagnosis include:2
Urine porphyrin levels (mostly uroporphyrin) markedly increased
Fecal porphyrin levels normal or slightly increased
Plasma porphyrin levels normal or slightly increased
Erythrocyte PBG deaminase levels decreased by ∼50%
Accuracy and speed
are critical in the diagnosis of an acute porphyric attack.2
References:
- Bonkovsky HL, Maddukuri VC, Yazici C, Anderson KE, Bissell M, Bloomer JR, et al. Acute porphyrias in the USA: features of 108 subjects from porphyrias consortium. Am J Med 2014;127:1233‑1241.
- Anderson KE, Bloomer JR, Bonkovsky HL, et al. Recommendations for the Diagnosis and Treatment of the Acute Porphyrias. Ann Intern Med 2005;142:439‑450.