Consecutive Liver and Bone Marrow Transplantation for Erythropoietic Protoporphyria: Case Report and Literature Review.

BACKGROUND: Erythropoietic protoporphyria (EPP) is a rare inherited disease of heme biosynthesis resulting in the accumulation of protoporphyrin, characterized by liver failure in a minority of cases. Although liver transplant (LT) is the therapeutic strategy for advanced hepatic disease, it does not correct the primary defect, which leads to recurrence in liver graft. Thus, hematopoietic stem cell transplantation (HSCT) is an approach for treating EPP. METHODS: We aim to describe the first sequential LT and HSCT for EPP performed in Latin America, besides reviewing the present-day literature. RESULTS: The patient, a 13-year-old female with a history of photosensitivity, presented with symptoms of cholestatic and hepatopulmonary syndrome and was diagnosed with EPP. Liver biopsy demonstrated cirrhosis. She was submitted to a successful LT and showed improvement of respiratory symptoms. However, she had disease recurrence on the liver graft. She underwent a myeloablative HSCT using a matched unrelated donor, conditioning with BuCy (busulfan and cyclophosphamide), and GvHD (graft vs. host disease) prophylaxis with ATG (thymoglobulin), tacrolimus and methotrexate. Neutrophil engraftment occurred on D+18. She has presented mixed chimerism, but normalization of PP levels, being 300 days after HSCT, in good state of health and normal liver function. CONCLUSIONS: Consecutive LT and HSCT for EPP is a procedure that has been described in 10 cases in the literature and, even though these patients are a highly diversified population, studies have shown favorable results. This concept of treatment should be considered in patients with established liver disease.

Protoporphyrin IX-induced phototoxicity: Mechanisms and therapeutics.

Protoporphyrin IX (PPIX) is an intermediate in the heme biosynthesis pathway. Abnormal accumulation of PPIX due to certain pathological conditions such as erythropoietic protoporphyria and X-linked protoporphyria causes painful phototoxic reactions of the skin, which can significantly impact daily life. Endothelial cells in the skin have been proposed as the primary target for PPIX-induced phototoxicity through light-triggered generation of reactive oxygen species. Current approaches for the management of PPIX-induced phototoxicity include opaque clothing, sunscreens, phototherapy, blood therapy, antioxidants, bone marrow transplantation, and drugs that increase skin pigmentation. In this review, we discuss the present understanding of PPIX-induced phototoxicity including PPIX production and disposition, conditions that lead to PPIX accumulation, symptoms and individual differences, mechanisms, and therapeutics.

Liver involvement in patients with erythropoietic protoporphyria: retrospective analysis of clinicopathological features of 5 cases.

Erythropoietic protoporphyria (EPP) is a rare inherited disease whose morbidity is about 1:75,000 to 1:200,000. It is caused by the deficiency of porphyrin ferrochelatase (FECH). Liver involvement in EPP is even rarer. The diagnosis of EPP with liver involvement mainly relies on clinical manifestations, laboratory examinations, histopathological examinations and genetic testing, which is still a huge challenge for both clinicians and pathologists. Here, 5 cases of EPP with liver injury were collected, and the clinicopathological features of these patients were analyzed. The clinical manifestations and laboratory examinations varied from person to person, whereas the liver biopsies showed that there were dark brown deposits within the hepatocytes, Kupffer cells, bile canaliculi and the lumen of bile ducts, which was a constant finding by histopathological examination. Gene tests were conducted in two of the five cases, and the results confirmed the diagnosis. Fully understanding of the diseases can help us reduce the rate of missed diagnosis and provide proper treatment as early as possible.

Clinical and dermoscopic changes of acquired melanocytic nevi of patients treated with afamelanotide.

BACKGROUND: Afamelanotide (AFA) is a synthetic analogue of α-melanocyte-stimulating hormone that is approved for the treatment of patients affected by erythropoietic protoporphyria (EPP). AFA induces a "sun free" tanning and changes of acquired melanocytic nevi (AMN) that are generically described as "darkening". OBJECTIVES: To assess clinical and dermoscopic AMN changes during AFA treatment. METHODS: Adult EPP patients treated with two AFA implants 50 days apart were enrolled. They underwent a clinical and dermoscopic examination of all AMN at baseline (T0), and after 5 (T1) and 12 (T2) months from the first AFA implant. The general pattern, symmetry, number, and size of pigmented globules, morphology of the pigment network, and dermoscopic melanoma features were assessed. RESULTS: Fifteen patients were enrolled with 103 AMN. At T1 all reticular and 2-component AMN showed a focal network thickening that returned to baseline by T2. The increase of globules' number was observed at T1 but not at T2. The difference in number was not influenced by patients' age or phototype. Dermoscopic changes suggestive of malignancy were never seen. The development of new AMN was never registered. CONCLUSIONS: AFA treatment induces reversible changes of AMN dermoscopic morphology without findings suggestive of malignant transformation and it does not stimulate the development of new AMN.

Updates on the diagnosis and management of the most common hereditary porphyrias: AIP and EPP.

The porphyrias are a family of metabolic disorders caused by defects in the activity of one of the enzymes in the heme biosynthetic pathway. Acute intermittent porphyria (AIP), caused by autosomal dominant mutations in the gene encoding hydroxymethylbilane synthase, can lead to hepatocyte overaccumulation and systemic distribution of the proximal porphyrin precursors, 5-aminolevulinic acid (ALA) and porphobilinogen (PBG). ALA and PBG are toxic to neurons and extrahepatic tissue and cause the neurovisceral clinical manifestations of AIP. Management of AIP includes awareness and avoidance of triggering factors, infusions of hemin for severe acute attacks, and, if indicated for chronic suppressive therapy, maintenance treatment with hemin or givosiran, a small interfering RNA molecule that antagonizes ALA synthase 1 transcripts. Erythropoietic protoporphyria (EPP) is most commonly caused by autosomal recessive mutations in the gene encoding ferrochelatase (FECH), the heme pathway terminal enzyme. FECH deficiency leads to erythrocyte overaccumulation and high plasma levels of lipophilic protoporphyrins that photoactivate in the skin, causing burning pain and erythema. Protoporphyrins excreted in the bile can cause gallstones, cholestasis, fibrosis, and ultimately liver failure. Management of EPP includes skin protection and afamelanotide, an α-melanocyte stimulating hormone analog that increases melanin pigment and reduces photoactivation. Liver transplantation may be necessary for severe EPP-induced liver complications. Because AIP and EPP arise from defects in the heme biosynthetic pathway, hematologists are often consulted to evaluate and manage suspected or proven porphyrias. A working knowledge of these disorders increases our confidence and effectiveness as consultants and medical providers.

Inflammatory involvement into phototoxic reaction in erythropoietic protoporphyria (EPP) patients.

Phototoxic reaction is a known feature of EPP at least in part triggered by the oxidative status, complement system activation, and mast cell response. The aim of this study was to verify some aspects involved in phototoxic reaction during a season. The complement system was evaluated by C3 assay, alternative pathway by factor-B, and classical pathway by C1q; oxidative status was tested with malondialdehyde (MDA) and mast cell by IL-10 assay. The serum samples were collected in winter and summer from 19 EPP patients and 13 controls. The reaction to sun exposure within each group was monitored without any invasive treatment. In summer, C3 and factor B were higher in patients than in controls (p = 0.002 and < 0.0001 respectively), while no change was detected for C1q. The oxidative stress was increased in summer in comparison with the control group (p = 0.04), and IL-10 an assay was normal in both seasons. The correlation between the C3 and factor-B in summer was significant. This study shows that the phototoxic reaction is not limited to the dermis but can also exert a systemic response, which could affect the general health of a patient. The knowledge of the pathophysiology of phototoxic reaction is essential for identifying new disease markers useful for improving clinical studies of known and future drugs.

The essential role of the transporter ABCG2 in the pathophysiology of erythropoietic protoporphyria.

Erythropoietic protoporphyria (EPP) is an inherited disease caused by loss-of-function mutations of ferrochelatase, an enzyme in the heme biosynthesis pathway that converts protoporphyrin IX (PPIX) into heme. PPIX accumulation in patients with EPP leads to phototoxicity and hepatotoxicity, and there is no cure. Here, we demonstrated that the PPIX efflux transporter ABCG2 (also called BCRP) determines EPP-associated phototoxicity and hepatotoxicity. We found that ABCG2 deficiency decreases PPIX distribution to the skin and therefore prevents EPP-associated phototoxicity. We also found that ABCG2 deficiency protects against EPP-associated hepatotoxicity by modulating PPIX distribution, metabolism, and excretion. In summary, our work has uncovered an essential role of ABCG2 in the pathophysiology of EPP, which suggests the potential for novel strategies in the development of therapy for EPP.

Management of Patients With Erythropoietic Protoporphyria-Related Progressive Liver Disease.

Erythropoietic protoporphyria (EPP) is an inherited metabolic disorder of heme synthesis resulting from overproduction of protoporphyrin IX (PPIX), which can lead to progressive liver disease characterized by recurrent EPP crises and end-stage liver disease. We used the Australian Transplant Registry to identify 5 patients referred for liver transplantation between 2008 and 2017. A total of 4 patients had EPP secondary to ferrochelatase deficiency, and 1 patient had X-linked EPP. No patient had follow-up with a specialist prior to the diagnosis of progressive liver disease. There were 3 patients who underwent orthotopic liver transplantation, whereas 2 died while on the transplant waiting list. Parenteral PPIX-lowering therapy was used in 4 patients and was effective in 3 patients, although 2 of these had rebound porphyria and worsening liver function following a decrease in the intensity of therapy. Early disease recurrence in the allograft following transplantation occurred in 2 patients requiring red cell exchange (RCE) to successfully attain and maintain low PPIX levels, but RCE was associated with hemosiderosis in 1 patient. Allogeneic stem cell transplantation (AlloSCT) was performed in 2 patients. One failed engraftment twice, whereas the second rejected the first graft but achieved full donor chimerism with a second graft and increased immunosuppression. In conclusion, our observations suggest that progressive liver disease needs parenteral PPIX-lowering treatment with the intensity adjusted to achieve a target Erc-PPIX level. Because EPP liver disease is universally recurrent, AlloSCT should be considered in all patients with adequate immunosuppression to facilitate engraftment. RCE appears to be effective for recurrent EPP liver disease but is associated with an increased risk of iron overload.

Diagnosis of erythropoietic protoporphyria with severe liver injury: A case report.

BACKGROUND: Porphyria is a rare disease with complex classification. Erythropoietic protoporphyria (EPP) is an autosomal recessively inherited disease, and most are caused by mutations in the FECH gene. EPP combined with liver injury is even rarer. CASE SUMMARY: This paper reports a case of EPP which was admitted to the hospital with abnormal liver function and diagnosed by repeated questioning of medical history, screening of common causes of severe liver injury, and second generation sequencing of the whole exon genome. We also summarize the clinical characteristics of EPP with liver injury, and put forward some suggestions on EPP to provide a reference for the diagnosis of such rare disease. CONCLUSION: A new mutation locus (c.32_35dupCCCT) which may be related to the disease was found by detecting the FECH gene in the pedigree of this case.

Digital PCR (dPCR) analysis reveals that the homozygous c.315-48T>C variant in the FECH gene might cause erythropoietic protoporphyria (EPP).

Alterations in the ferrochelatase gene (FECH) are the basis of the phenotypic expressions in erythropoietic protoporphyria. The phenotype is due to the presence of a mutation in the FECH gene associated in trans to the c.315-48 T > C variant in the intron 3. The latter is able to increase the physiological quota of alternative splicing events in the intron 3. Other two variants in the FECH gene (c.1-252A > G and c.68-23C > T) have been found to be associated to the intron 3 variant in some populations and together, they constitute a haplotype (ACT/GTC), but eventually, their role in the alternative splicing event has never been elucidated. The absolute number of the aberrantly spliced FECH mRNA molecules and the absolute expression of the FECH gene were evaluated by digital PCR technique in a comprehensive cohort. The number of splicing events that rose in the presence of the c.315-48 T > C variant, both in the heterozygous and homozygous condition was reported for the first time. Also, the percentage of the inserted FECH mRNA increased, even doubled in the T/C cases, compared to T/T cases. The constant presence of variants in the promoter and intron 2 did not influence or modulate the aberrant splicing. The results of FECH gene expression suggested that the homozygosity for the c.315-48 T > C variant could be considered pathological. Thus, this study identified the homozygotes for the c.315-48 T > C variant as pathological. By extension, when the samples were categorised according to the haplotypes, the GTC haplotype in homozygosis was pathological.

[Clinicopathologic features of three cases of erythropoietic protoporphyria with liver involvement].

Objective: To investigate the clinicopathologic features of the erythropoietic protoporphyria (EPP) with liver involvement. Methods: The clinical findings and hepatic biopsy of 3 cases of EPP diagnosed between July, 2011 to August, 2014 with liver involvement were reviewed, with relevant literature review. Results: All patients presented with persistent and refractory abdominal pain, with obvious jaundice and deranged liver function. Imaging showed homogeneous hepatomegaly in all patients. Histologically, the hepatocytes were edematous, and contained numerous cytoplasmic globular brown pigments and bile pigments, which were also found in Kupffer cells, in the bile canaliculi and in some of dilated sinusoid. The pigments were of different sizes and showed uneven distribution. Some pigments showed bright red or yellow birefringence with a distinctive central maltese cross configuration on polarizing microscopy. Furthermore, some hepatocytes showed piecemeal necrosis and steatosis, the portal tracts were usually infiltrated by lymphocytes, with fibroplasia and biliary ductular reaction. There was no dilatation of intrahepatic bile ducts. Conclusion: Full understanding of the clinical and pathological features of EPP with liver involvement can help to recognize this small group of patients, and to offer proper effective treatments.

Modeling the ferrochelatase c.315-48C modifier mutation for erythropoietic protoporphyria (EPP) in mice.

Erythropoietic protoporphyria (EPP) is caused by deficiency of ferrochelatase (FECH), which incorporates iron into protoporphyrin IX (PPIX) to form heme. Excitation of accumulated PPIX by light generates oxygen radicals that evoke excessive pain and, after longer light exposure, cause ulcerations in exposed skin areas of individuals with EPP. Moreover, ∼5% of the patients develop a liver dysfunction as a result of PPIX accumulation. Most patients (∼97%) have a severe FECH mutation (Mut) in trans to an intronic polymorphism (c.315-48C), which reduces ferrochelatase synthesis by stimulating the use of an aberrant 3' splice site 63 nt upstream of the normal site for exon 4. In contrast, with the predominant c.315-48T allele, the correct splice site is mostly used, and individuals with a T/Mut genotype do not develop EPP symptoms. Thus, the C allele is a potential target for therapeutic approaches that modify this splicing decision. To provide a model for pre-clinical studies of such approaches, we engineered a mouse containing a partly humanized Fech gene with the c.315-48C polymorphism. F1 hybrids obtained by crossing these mice with another inbred line carrying a severe Fech mutation (named m1Pas) show a very strong EPP phenotype that includes elevated PPIX in the blood, enlargement of liver and spleen, anemia, as well as strong pain reactions and skin lesions after a short period of light exposure. In addition to the expected use of the aberrant splice site, the mice also show a strong skipping of the partly humanized exon 3. This will limit the use of this model for certain applications and illustrates that engineering of a hybrid gene may have unforeseeable consequences on its splicing.

[Cutaneous changes in long-standing erythropoietic protoporphyria]. / Hautveränderungen bei lange bestehender erythropoetischer Protoporphyrie.

Erythropoietic protoporphyria results in highly increased photosensitivity of the skin. Solar irradiation causes sunburn-like symptoms with erythema, edema and wheals. We report the case of a 60-year-old man suffering from erythropoietic protoporphyria since his childhood who additionally developed chronic cutaneous lichenoid papules in sun-exposed skin areas. Vaporization with both electrocautery and carbon dioxide laser proved to be a successful treatment option.

A precursor-inducible zebrafish model of acute protoporphyria with hepatic protein aggregation and multiorganelle stress.

Protoporphyria is a metabolic disease that causes excess production of protoporphyrin IX (PP-IX), the final biosynthetic precursor to heme. Hepatic PP-IX accumulation may lead to end-stage liver disease. We tested the hypothesis that systemic administration of porphyrin precursors to zebrafish larvae results in protoporphyrin accumulation and a reproducible nongenetic porphyria model. Retro-orbital infusion of PP-IX or the iron chelator deferoxamine mesylate (DFO), with the first committed heme precursor α-aminolevulinic acid (ALA), generates high levels of PP-IX in zebrafish larvae. Exogenously infused or endogenously produced PP-IX accumulates preferentially in the liver of zebrafish larvae and peaks 1 to 3 d after infusion. Similar to patients with protoporphyria, PP-IX is excreted through the biliary system. Porphyrin accumulation in zebrafish liver causes multiorganelle protein aggregation as determined by mass spectrometry and immunoblotting. Endoplasmic reticulum stress and induction of autophagy were noted in zebrafish larvae and corroborated in 2 mouse models of protoporphyria. Furthermore, electron microscopy of zebrafish livers from larvae administered ALA + DFO showed hepatocyte autophagosomes, nuclear membrane ruffling, and porphyrin-containing vacuoles with endoplasmic reticulum distortion. In conclusion, systemic administration of the heme precursors PP-IX or ALA + DFO into zebrafish larvae provides a new model of acute protoporphyria with consequent hepatocyte protein aggregation and proteotoxic multiorganelle alterations and stress.-Elenbaas, J. S., Maitra, D., Liu, Y., Lentz, S. I., Nelson, B., Hoenerhoff, M. J., Shavit, J. A., Omary, M. B. A precursor-inducible zebrafish model of acute protoporphyria with hepatic protein aggregation and multiorganelle stress.

[A patient diagnosed herself with erythropoietic protoporphyria after googling photosensitivity]. / Googlede lysfølsomhed og diagnosticerede sig selvmed erytropoietisk protoporfyri.

Erythropoietic protoporphyria (EPP) is rare genetic disease caused by decreased activity of the eighth enzyme in the haem synthesis. Patients are photosensitive, getting stinging and burning sensations in the skin after sun exposure. Delayed diagnosis of these patients is not seldom because of the rarity in combination with not always visible skin symptoms. This is a case report of a 43-year-old woman who diagnosed herself with EPP after googling photosensitivity. Genetic testing revealed a formerly undescribed mutation, c. 1096-3C>G in combination with the polymorphism, c.333-48T>C.