Acute hepatic porphyria in Denmark; a retrospective study.

Background: Acute hepatic porphyria (AHP) constitutes a class of rare diseases caused by reduced function in enzymes of the heme-biosynthetic pathway. AHP includes acute intermittent porphyria (AIP), hereditary coproporphyria (HCP), variegate porphyria (VP) and the extremely rare δ-aminolevulinic-dehydrase deficiency porphyria (ADP). This retrospective study describes characteristics of the Danish AHP patient population.

Methods: Department of Endocrinology at Odense University Hospital serves as national AHP center. We performed a 5-year retrospective description of our AHP cohort using electronic patient journals. We included general symptoms, number of acute attacks, hospitalization rates, long-term sequelae and symptoms, and grouped patients according to creatinine-adjusted urinary baseline excretion (i.e., outside attacks) of the porphyrin precursor porphobilinogen (PBG) in normal-, moderate- and high-excretion and unknown.

Results: The cohort contained 129 AHP patients, hereof 100 AIP, 12 HCP and 17 VP. Median age was 46.3 (32.1-62.0) years, and 85 (65.9%) were female. During the 5-years, 38 (29.5%) patients experienced symptoms. Hereof, 20 patients were hospitalized with acute attacks or chronic symptoms and treated with human hemin (n = 14). Most frequently reported symptoms were abdominal pain, nausea, vomiting, and neurological disturbances. Symptoms were more common in patients with high PBG baseline excretion (n = 39) as compared to those with moderate (n = 31) or normal (n = 40) PBG excretion (p = 0.002). Furthermore, females dominated the symptomatic group (68.4%).

Conclusion: As reported internationally, AHP is more commonly diagnosed and symptomatic in women, and AIP was the most frequent AHP subtype. Those with an elevated urinary baseline PBG secretion were more likely to report AHP-related symptoms.