[Neurocutaneous porphyrias]

The Porphyrias

The porphyrias are clinically variable and genetically heterogeneous, predominantly hereditary metabolic diseases, which are caused by a dysfunction of specific enzymes in heme biosynthesis. Here, we provide an overview of the etiopathogenesis, clinic, differential diagnosis, laboratory diagnostics and therapy of these complex metabolic disorders and cover in detail the most common form of porphyria worldwide (porphyria cutanea tarda), the most frequent childhood porphyria (erythropoietic protoporphyria), and the most common neurocutaneous porphyria (variegate porphyria).

Greater disease burden of variegate porphyria than hereditary coproporphyria: An Israeli nationwide study of neurocutaneous porphyrias

Hereditary coproporphyria (HCP) and variegate porphyria (VP) are referred to as neurocutaneous porphyrias (NCP). Data concerning their systemic presentation are limited and no direct attempt of comparison of the two has ever been made. Our aim was to describe the type and frequency of systemic manifestations of NCPs in Israeli patients. A cross-sectional survey was conducted. The study population included all patients with NCP diagnosed at the Israeli National Service for Biochemical Diagnoses of Porphyrias (INSP) between 1988 and 2019. Of the 83 patients with NCP who were alive in 2019, 61 (73%) completed the survey, 40 with VP and 21 with HCP. Systemic symptoms were reported by 63% of the VP group and 62% of the HCP group (p = .96); corresponding rates of cutaneous symptoms were 58% and 5% (p < .001). We found no association between the occurrence of systemic and cutaneous symptoms. Among patients with systemic involvement, abdominal pain was the predominant systemic symptom, found in 64% of the VP group and 69% of the HCP group; Analysis of symptom frequency showed that in 68% of the VP group, systemic symptoms (either abdominal, musculoskeletal or neuropsychiatric) occurred on a daily/weekly basis, whereas the HCP group experienced less than one symptom per week (p < .001). This nationwide study depicts a significantly heavier disease burden in VP patients compared to HCP owing to its more frequent neurovisceral and cutaneous manifestations.