Key terms and definitions in acute porphyrias: Results of an international Delphi consensus led by the European porphyria network

Abstract

Acute porphyrias are a group of rare inherited disorders causing acute neurovisceral attacks. Many terms used frequently in the literature and clinical practice are ambiguous, which can lead to confusion in the way patients are managed, studied, and reported in clinical studies. Agreed definitions are a necessary first step in developing management guidelines and will facilitate communication of results of future clinical research. The Delphi method was used to generate consensus on key terms and definitions in acute porphyria. The process started with a brainstorming phase offered to all members of the European Porphyria Network followed by two Delphi rounds among international experts in the field of porphyria (the Acute Porphyria Expert Panel). A consensus of 75% or more was defined as the agreement threshold. A total of 63 respondents from 26 countries participated in the brainstorming phase, leading to the choice of nine terms and definitions. A total of 34 experts were invited to take part in the Delphi rounds. Seven of the initial nine terms and definitions which entered the first Delphi round achieved the threshold for agreement. Following a second Delphi round, all nine definitions achieved agreement. Agreement on the definitions for nine important terms describing acute porphyrias represents a significant step forward for the porphyria community. It will facilitate more accurate comparison of outcomes among porphyria centres and in clinical trials and provide a strong framework for developing evidence‐based clinical guidelines.

Porphyrien

“…Die Penetranz der AIP, der häufigsten akuten Porphyrie, ist für Genträger innerhalb betroffener Familien 23 %, für Genträger innerhalb der Allgemeinbevölkerung < 1 % (latente Porphyrie mit Risiko bzw. niedrigem Risiko) [4,5]. Selten finden sich bei akuten hepatischen Porphyrien homozygote bzw.…”

Preventing hyperhomocysteinemia using vitamin B6 supplementation in Givosiran-treated acute intermittent porphyria: Highlights from a case report and brief literature review

“…We report the case of a 72-year old woman with sporadic AIP as defined recently in international consensus study [ 23 ]. Her history includes high blood pressure treated with atenolol 50 mg/day, epilepsy and cerebral sylvian aneurysms.…”

Potential Biomarkers for the Earlier Diagnosis of Kidney and Liver Damage in Acute Intermittent Porphyria

“…According to these new definitions, 2 had recurrent acute porphyria, 20 had sporadic acute porphyria, 3 were symptomatic high excreters, 7 had asymptomatic acute porphyria, 6 were asymptomatic high excreters, and 12 had latent porphyria but with the disclaimer that the self-reported previous AIP attacks were not always biochemically confirmed. High excretion of urine PBG/creatinine was defined by Stein et al [16] as a urine PBG/creatinine ratio at least 4 times the upper limit of normal, which when applied to our study is urine PBG/creatinine > 6 µmol/mmol (i.e., 1.5 µmol/mmol × 4). We had previously stored EDTA plasma from all 50 cases and matched controls and stored urine from 48 cases and their matched controls at −80 • C. Each participant delivered blood and urine samples only once.…”