High prevalence of HFE gene mutations in patients with porphyria cutanea tarda in the Czech Republic

Background  Iron overload and hepatitis C virus (HCV) infection are independent factors which are thought to play a role in the pathogenesis of porphyria cutanea tarda (PCT).
Objectives  To determine the prevalence of the HFE gene mutations p.Cys282Tyr (C282Y), p.His63Asp (H63D) and p.Ser65Cys (S65C), the p.Tyr250X (Y250X) mutation of the TFR2 gene, and HCV infection in patients with PCT in the Czech population, and to make comparison of the iron status among the respective genotypes.
Methods  Iron metabolism indices, results of mutational analysis and serological markers of HCV infection were examined in 63 patients with PCT.
Results  The HFE gene mutations were detected in 70% of patients with PCT compared with 35% in the control group ( P  <   0·001). Mean serum ferritin levels were increased in all genotypes, the highest being in homozygotes for the p.Cys282Tyr mutation. HCV infection was detected in only 8% of patients with PCT.
Conclusions  There was a very high prevalence of the p.Cys282Tyr and p.His63Asp mutations observed in patients with PCT accompanied by mild degrees of iron overload, which was genotype dependent.     

HFE mutations and transferrin receptor polymorphism analysis in porphyria cutanea tarda: a prospective study of 36 cases from southern France

BACKGROUND: Porphyria cutanea tarda (PCT) is associated in most cases with iron overload, which may participate in decreased activity of uroporphyrinogen decarboxylase in the liver. The aetiology of this iron overload remains unknown; however, it has been demonstrated that mutations of HFE, the genetic haemochromatosis gene, might be present in a significant proportion of Anglo-Saxon and Italian patients. Furthermore, transferrin receptor polymorphism may influence the affinity of this receptor to its ligand with a subsequent increase of cellular iron absorption and storage. OBJECTIVES: To evaluate the incidence and spectrum of HFE mutations and the relative frequency of the two main alleles of transferrin receptor in patients with PCT originating from southern France, and to evaluate the relationship of these genetic data with iron status, and with hepatitis B and C and human immunodeficiency virus (HIV) infections. METHODS: Thirty-six consecutive patients with either sporadic or familial PCT were prospectively included between 1997 and 2000. Search for the presence of the three main mutations of the HFE gene and identification of the transferrin receptor alleles were performed using polymerase chain reaction followed by enzymatic digestion. Iron parameters and viral status for hepatitis B and C viruses and HIV were determined. RESULTS: Seven patients (19%) showed heterozygous C282Y mutation, but no C282Y homozygote was present; five patients (14%) carried homozygous H63D mutation, while eight (22%) were heterozygous for this mutation. One patient was heterozygous for the S65C mutation (3%). Iron parameters demonstrated overload in all patients, without a clear difference between patients with and without deleterious mutations of the HFE gene. Infection by hepatitis C virus was documented in 20 patients (56%), and was significantly less frequent in patients with deleterious HFE mutations. The profile of transferrin receptor alleles in PCT patients did not show significant variation compared with the general population. CONCLUSIONS: This study confirms the high frequency of HFE mutations in patients with PCT and supports the hypothesis that HFE gene abnormalities might play a significant part in the PCT pathomechanism, probably through iron overload; by contrast, transferrin receptor polymorphisms do not appear to play a significant part in iron overload in PCT.     

Porphyria cutanea tarda,C282Y,H63D and S65C HFE gene mutations and hepatitis C infection: a study from southern France

BACKGROUND: To evaluate the role of genetic factors in the pathogenesis of porphyria cutanea tarda (PCT) and their association with chronic hepatitis C. OBJECTIVE: To investigate the relations between hemochromatosis gene (HFE) mutations and PCT in the south of France and their links with chronic hepatitis C virus (HCV) infection. METHODS: The genotype for the C282Y, H63D and S65C mutations of HFE was determined in 33 patients with PCT, 46 patients with HCV infection but without PCT and 58 controls. Iron status and HCV, HBV and HIV serologies were studied in all patients. RESULTS: A statistically significant increase in the C282Y mutation was found in PCT patients. No difference was found for H63D or S65C mutations. The prevalence of HCV infection was higher in PCT patients than controls. CONCLUSIONS: C282Y mutations and HCV infection but not H63D or S65C mutations are PCT-triggering or associated factors in the south of France.     

Role of the hemochromatosis gene in prophyria cutanea tarda. Prospective study of 56 cases]

BACKGROUND: The cause of iron overload in prophyria cutanea tada is unknown. The aim of this work was to determine the frequency of the hemochromatosis gene (HFE) in 56 patients with porphyria cutanea tarda. We analyzed the relationship between HFE mutations and biochemical abnormalities in porphyria cutanea tarda and the interaction with other triggering factors of porphyria cutanea tarda (alcohol abuse, hepatitis C, drugs).PATIENTS AND METHODS: Hepatitis C, alcohol abuse, drug intake and HFE mutations were determined in 56 patients with porphyria cutanea tarda (44 men and 12 women). Iron status was determined from transferrin saturation, serum iron, and serum ferritin. Liver metabolism was determined from liver chemistries: alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transpeptidase.RESULTS: Thirty-nine patients (69.4 p. 100) carried HFE mutations, 18 (32.1 p. 100) were H63D heterozygous, 4 (7.1 p. 100) were H63D homozygous, 9 (16 p. 100) C282Y heterozygous, 8 (14.2 p. 100) compound C282Y/H63D heterozygous and none were C282Y homozygous. Comparison between porphyria cutanea tarda with and without mutations showed that compound C282Y/H63D heterozygous status was significantly linked to iron overload: transferrin saturation=0.61 vs 0.39 (p=0.0001) and serum iron=32.9 vs 22.4 (p=0.0046). H63D homozygous status was linked to iron overload but non-significantly: transferrin sturatin=0.53 vs 0.39 (p=0.06). The class with high iron overload (transferrin saturation > 0.45) was not linked with triggering factors of porphyria cutanea tarda. Hepatatic cytolysis was linked to alcohol abuse and hepatitis C but not to HFE mutations.DISCUSSION: The frequencies of HFE mutations in Lyons France are halfway between Anglo-Saxon and Italian papers, highlighting the Celtic origin of C282Y mutation. Compound heterozygous and to a lesser degree H63D homozygous status explained the highest iron overload in our patients. This favors clinical expression of porphyria cutanea tarda. This iron overload due to HFE mutations is a new triggering factor of porphyria cutanea tarda independent of classical triggering factors: mutation of the erythrocytic uroporpyrinogen decarbocylase gene, alcohol abuse, hepatitis C, and drugs.     

The prevalence of HFE C282Y gene mutation is increased in Spanish patients with porphyria cutanea tarda without hepatitis C virus infection

OBJECTIVES: To investigate the role of C282Y and H63D mutations, and hepatitis C virus (HCV) infection in the pathogenesis of porphyria cutanea tarda (PCT). DESIGN: Prospective case-control study. SETTING: A large clinical and research institute for the study and treatment of cutaneous diseases in Barcelona, Spain. PATIENTS: Ninety-nine consecutive patients with PCT and one hundred and twenty-six control patients (76 healthy subjects and 50 patients chronically infected with HCV), were recruited. MAIN OUTCOME MEASURES: The frequency of the C282Y and H63D mutations in patients with PCT vs. controls and the relationship of these mutations with HCV infection, and iron status, as judged by serum iron, liver iron and ferritin levels. RESULTS: C282Y mutation was significantly increased in PCT patients. This mutation was more frequent among non-HCV-infected patients. Increased ferritin levels and hepatic iron overload were also observed in PCT patients with heterozygous C282Y state. H63D mutation was only significantly increased among PCT patients with chronic hepatitis C infection. No significant iron overload was observed in patients with H63D mutation. CONCLUSIONS: This study confirms the high frequency of C282Y mutation in patients with PCT and its relationship with iron overload. The C282Y mutation has a relevant role in Spanish patients with PCT not associated with HCV chronic infection. On the other hand, the prevalence of the H63D mutation seems not to be increased in patients with PCT. The possibility of an association between HCV infection and H63D mutation in inducing PCT can be hypothesized.     

STUDIES ON LOW DOSE CHLOROQUINE THERAPY AND THE ACTION OF CHLOROQUINE IN SYMPTOMATIC PORPHYRIA

Summary.— Eight patients with symptomatic porphyria (porphyria cutanea tarda symptomatica, PCT) were treated with small doses of chloroquin sulphate over periods ranging from 2 to 16 weeks. A good clinical and biochemical response was obtained in all but one patient, who relapsed after initial improvement. Manifestations of acute untoward reaction were seen in one patient only. It is concluded that low dose chloroquine therapy is both safe and effective in PCT.
Studies in porphyric rats indicate that the mechanism of action of chloroquine in PCT is probably not related, as has been suggested, to the formation of a chloroquine-porphyrin complex which damages liver cells and thereby leads to a reduction in hepatic porphyrin stores.
Chloroquine therapy led to increased urinary iron excretion and an increase in the desferrioxamine-chelatable iron in patients with PCT. It is suggested that the prolonged beneficial effects of chloroquine treatment may be related to reduction in a specific pool of liver iron.     

Precipitating factors of porphyria cutanea tarda in Brazil with emphasis on hemochromatosis gene (HFE) mutations. Study of 60 patients

BACKGROUND

Porphyria cutanea tarda is the most common form of porphyria, characterized by the decreased activity of the uroporphyrinogen decarboxylase enzyme. Several reports associated HFE gene mutations of hereditary hemochromatosis with porphyria cutanea tarda worldwide, although up to date only one study has been conducted in Brazil.

OBJECTIVES

Investigation of porphyria cutanea tarda association with C282Y and H63D mutations in the HFE gene. Identification of precipitating factors (hepatitis C, HIV, alcoholism and estrogen) and their link with HFE mutations.

METHODS

An ambispective study of 60 patients with PCT was conducted during the period from 2003 to 2012. Serological tests for hepatitis C and HIV were performed and histories of alcohol abuse and estrogen intake were investigated. HFE mutations were identified with real-time PCR.

RESULTS

Porphyria cutanea tarda predominated in males and alcohol abuse was the main precipitating factor. Estrogen intake was the sole precipitating factor present in 25% of female patients. Hepatitis C was present in 41.7%. All HIV-positive patients (15.3%) had a history of alcohol abuse. Allele frequency for HFE mutations, i.e., C282Y (p = 0.0001) and H63D (p = 0.0004), were significantly higher in porphyria cutanea tarda patients, compared to control group. HFE mutations had no association with the other precipitating factors.

CONCLUSIONS

Alcohol abuse, hepatitis C and estrogen intake are prevalent precipitating factors in our porphyria cutanea tarda population; however, hemochromatosis in itself can also contribute to the outbreak of porphyria cutanea tarda, which makes the research for HFE mutations necessary in these patients     

Porphyria cutanea tarda mit sklerodermiformen Veränderungen und Hämochromatose

A 55-year-old woman presented with blistering on the back of her hands and shiny, thickened skin in her décolletage. Laboratory examination revealed increased urinary total and high carboxylated porphyrins and homozygosity for mutation C282Y in the HFE gene. Histopathology showed thickened collagen fibers in the presternal region. Based on these findings we made the diagnosis of porphyria cutanea tarda with pseudoscleroderma and hemochromatosis. Pseudoscleroderma is a rare complication of PCT but can also constitute the first cutaneous symptom of the disease, leading the way to diagnosis. Usually, adequate treatment of PCT with normalization of porphyrin values also results in improvement of pseudoscleroderma.     

Results of treatment of porphyria cutanea tarda with bloodletting and chloroquine

In 59 patients showing clear clinical and biochemical signs of porphyria cutanea tarda (PCT), we tested 3 different modes of therapy: 20 patients received combined treatment with repeated bleeding and chloroquine, 24 patients were exclusively treated with oral chloroquine in low doses, and 15 patients underwent repeated phlebotomy only. On an average, the time necessary for remission amounted to 3.5, 10.2, and 12.5 months, respectively. So the combined therapy proved the quickest. In patients with the acquired form of PCT, the pattern of urinary porphyrin normalized; those suffering from hereditary PCT retained the typically high uro/copro ratio. The values of the plasma porphyrin count and the plasma porphyrin index (PPI), which had been greatly enhanced before, went down to normal after therapy.     

Iron metabolism and chloroquine phosphate therapy in porphyria cutanea tarda

The knowledge about the influence of chloroquine phosphate (CQ) on the iron metabolism in porphyria cutanea tarda (PCT) is still insufficient. In a study on 138 PCT patients treated with CQ, we observed decreasing serum iron concentration, transferrin saturation, and hepatic siderosis, as well as an increasing level of transferrin. After a one-year therapy with CQ, the patients showed normal porphyrinuria. Since there were no statistical correlations between the degree of hepatic siderosis and porphyrinuria, and since we repeatedly found remission of the PCT in spite of the continued existence of hepatic siderosis, the removal of iron cannot be regarded as the only principle of action in CQ therapy. In comparison with chloroquine, phlebotomy obviously has--even with regard to the iron deposits--no decisive advantages.     

Hepcidin and HFE protein: Iron metabolism as a target for the anemia of chronic kidney disease

The anemia of chronic kidney disease and hemodialysis is characterized by chronic inflammation and release of cytokines, resulting in the upregulation of the iron hormone hepcidin, also increased by iron therapy and reduced glomerular filtration, with consequent reduction in iron absorption, recycling, and availability to the erythron. This response proves advantageous in the short-term to restrain iron availability to pathogens, but ultimately leads to severe anemia, and impairs the response to erythropoietin (Epo) and iron. Homozygosity for the common C282Y and H63D HFE polymorphisms influence iron metabolism by hampering hepcidin release by hepatocytes in response to increased iron stores, thereby resulting in inadequate inhibition of the activity of Ferroportin-1, inappropriately high iron absorption and recycling, and iron overload. However, in hemodialysis patients, carriage of HFE mutations may confer an adaptive benefit by decreasing hepcidin release in response to iron infusion and inflammation, thereby improving iron availability to erythropoiesis, anemia control, the response to Epo, and possibly survival. Therefore, anti-hepcidin therapies may improve anemia management in hemodialysis. However, HFE mutations directly favor hemoglobinization independently of hepcidin, and reduce macrophages activation in response to inflammation, whereas hepcidin might also play a beneficial anti-inflammatory and anti-microbic action during sepsis, so that direct inhibition of HFE-mediated regulation of iron metabolism may represent a valuable alternative therapeutic target. Genetic studies may offer a valuable tool to test these hypotheses and guide the research of new therapies.     

Does chloroquine therapy of porphyria cutanea tarda influence liver pathology?

Background  Porphyria cutanea tarda (PCT) is regularly associated with changes in liver tissue. On the other hand, systematic investigations are lacking on whether there is a correlation between the severity of liver damage and chloroquine treatment.
Patients and methods  During a 20-year period, liver biopsies were obtained in 89 patients with PCT confirmed by biochemical analysis of urine and feces and low-dose chloroquine therapy. Seventeen patients with alcohol-induced liver disease were excluded. In 8 of 63 patients, only a single biopsy was available. Classification of liver damage was performed according to the Riedel score. Electron microscopy was available from 24 patients. In a second group of patients, the HFE status was investigated and Berlin blue stains of liver biopsies were performed.
Results  There was no correlation between the duration of cutaneous symptoms and liver pathology. After 12 months chloroquine treatment, 45 patients (81%) disclosed an improvement of liver pathology, nine (16%) had no change, and a worsening was observed in one patient (3%). All patients achieved a complete clinical and biochemical remission. In 13 of 16 patients with a relapse, there was again a deterioration of liver damage. Patients with HFE mutations had a significant higher risk ( P  < 0.05) for hepatic siderosis.
Conclusions  The severity of liver damage was not correlated with the disease duration. Chloroquine treatment resulted in PCT remission (clinical and biochemical) and in 81% to an improvement of liver morphology.     

Update on enzyme and molecular defects in porphyria

Each porphyria results from decreased activity of one of the enzymes of haem biosynthesis. The molecular basis of enzyme deficiencies in acute intermittent porphyria (AIP), variegate porphyria (VP) and congenital erythropoietic porphyria (CEP) is outlined. All three conditions show extensive allelic heterogeneity. In the autosomal dominant disorders, AIP and VP, no genotype/phenotype correlations have been demonstrated, and the explanation for their low clinical penetrance remains uncertain. In AIP and VP, mutational analysis is superior to biochemical methods for screening families for latent porphyria. In the autosomal recessive condition, CEP, there is some genotype/phenotype correlation — one common mutation (C73R) being associated with severe disease in homozygotes. Porphyria cutanea tarda (PCT) is not a simple monogenic disorder. Patients appear to have an inherited susceptibility to inactivation of hepatic uroporphyrinogen decarboxylase (UROD) as part of a response to hepatocyte injury by alcohol, HCV and other agents. Inherited factors that, in combination, may predispose to PCT include mutations in the UROD gene, present in about 20% of patients, and the C282Y mutation in the haemochromatosis (HFE) gene.     

Porphyria cutanea tarda associated with Cys282Tyr mutation in HFE gene in hereditary hemochromatosis: a case report and review of the literature

Porphyria cutanea tarda (PCT) typically presents with complaints of fragile skin, dorsal hand vesicles, erosions, and scars, and increased levels of uroporphyrins. A case of PCT caused by iron overload associated with hereditary hemochromatosis (HH) is reported. The laboratory workup revealed the patient was homozygous for the Cys282Tyr mutation in the HFE (hemochromatosis) gene. The associated diagnosis of HH was critical because without early treatment, damage to vital organs and premature death could occur. This report highlights the important association of PCT with HH and reviews the role of key genetic and hormonal factors in iron regulation.     

Familial and sporadic porphyria cutanea tarda: clinical,biochemical and genetic features with emphasis on iron status

The manifestation of porphyria cutanea tarda reflects genetic and environmental factors. Mutations in the uroporphyrinogen decarboxylase gene, located at chromosome 1p34, discriminate familial porphyria cutanea tarda from sporadic cases. Furthermore, mutations in the haemochromatosis gene may be involved in the aetiology. In this study 53 unrelated Danish patients with porphyria cutanea tarda were classified according to uroporphyrinogen decarboxylase and haemochromatosis gene mutations and the genotype related to the clinical and biochemical data. Thirteen patients (25%) had familial porphyria cutanea tarda. The results signify the advantage of DNA diagnostics for identification of familial cases, as anamnestic data are doubtful and erythrocyte uroporphyrinogen decarboxylase activity measurements insufficient for correct classification. Eight patients with porphyria cutanea tarda (15%) were homozygous for the haemochromatosis gene C282Y mutation and 8 patients were heterozygous. Patients homozygous for the haemochromatosis related mutation showed biochemical evidence of excessive iron storage as well as increased urine porphyrin excretion levels. This seems to confirm a relationship between porphyria cutanea tarda and haemochromatosis. No differences were found between patients with sporadic and familial porphyria cutanea tarda regarding age of onset, clinical severity, sex distribution, liver function tests and iron storage parameters. However, daily alcohol intake and use of oestrogens were reported more frequently in the group of sporadic patients. It was found that women were over-represented in our study.     

Porphyria cutanea tarda.

Porphyria cutanea tarda (PCT) is the most frequent form of porphyria. The underlying enzymatic defect in PCT is a reduced activity of the enzyme uroporphyrinogen decarboxylase (Uro-D). Four different types of Uro-D disturbances are known. Pseudoporphyrias such as porphyria cutanea uraemica or drug-induced PCT-like skin symptoms are distinguished from PCT. Porphyrinogens such as estrogens or alcohol, or other inducers of P450 isoenzymes provoke PCT. Polymorphisms of P450 isoenzymes, iron overload and infection with hepatitis C virus play an important role in the etiopathogenesis of disease manifestation. Dominant clinical symptoms are bullae, increased cutaneous vulnerability, hypertrichosis and elastosis. Biochemically, total porphyrin levels in urine are increased with a predominance of uroporphyrin and heptacarboxylic porphyrin. Isocoproporphyrin is demonstrable in feces. Best therapeutic strategies are the oral administration of chloroquine 125 mg twice a week and repetitive bloodlettings or the combination of both.     

Porphyria cutanea tarda in south-east New South Wales

Thirteen patients with porphyria cutanea tarda diagnosed between 1994 and 2000 were reviewed to evaluate the precipitating factors and associations of porphyria cutanea tarda in a regional area of coastal and rural NSW. The majority had more than one precipitating factor, with excess alcohol intake, mutations in the haemochromatosis gene, chronic hepatitis C infection and oestrogen therapy being the most common. Antibodies to the hepatitis C virus were detected in 25% and these patients presented at a younger age. Of the patients tested for the two known haemochromatosis gene mutations, six (46%) had at least one copy of the C282Y mutation. Two (15%) patients were homozygous for the C282Y mutation and two (15%) were compound heterozygous for the C282Y and H63D mutations. All patients responded to venesection, which is the treatment of choice for the majority of patients with porphyria cutanea tarda.     

Five cases of porphyria cutanea tarda with mild cutaneous changes: evaluation of the efficacy of phlebotomy by the pattern analysis of urinary porphyrins

Five cases of porphyria cutanea tarda (PCT) with mild cutaneous changes are reported. Acute episodes of photosensitivity were not seen in all patients. Laboratory examinations showed a predominance of uroporphyrin (UP) excretion in the urine in 4 out of 5 cases. One case showed a relatively low urinary porphyrin level even though abnormality of the porphyrin pattern was present. Four cases showing a predominance of UP excretion in the urine revealed a high level of serum coproporphyrin (CP) as well. Histopathologically, all cases showed a deposition of PAS positive materials surrounding the small blood vessels in the upper dermis, in addition to the deposition of IgG materials visualized by the immunofluorescent technique. Phlebotomy was performed fifteen times in one case. The urinary porphyrin level was gradually reduced to normal levels and the urinary porphyrin pattern shifted from a predominance of UP and hepta-carboxyl porphyrin to a predominance of CP excretion. Analysis of the urinary porphyrin profile is useful as a laboratory tool for diagnosis or observation of the course of PCT, as well as for the quantitative analysis of urinary porphyrins.     

Treatment of porphyria cutanea tarda with chloroquine and phlebotomy

Treatment of porphyria cutanea tarda (PCT) with chloroquine risks serious side-effects so we have combined it with phlebotomy. One to four venesections were performed before the administration of chloroquine in to PCT patients. Equally high excretion of urinary porphyrins was achieved but the side-effects were reduced. Chloroquine may be used as a provocative diagnostic test for patients with a questionably latent PCT but this is safe is safe if phlebotomy is performed beforehand.     

Biochemical study of fecal porphyrin in porphyria cutanea tarda

Fecal, urinary and erythrocyte porphyrin analyses using the solvent extraction method were performed in 26 patients with porphyria cutanea tarda (PCT) and 144 normal controls. The levels of fecal uroporphyrin (UP) and coproporphyrin (CP) were markedly increased in the PCT group, especially in comparison with the protoporphyrin (PP) level. The values of the UP/PP and CP/PP ratios in the feces were also elevated over those in the control group. It appears that fecal porphyrin excretion is basically similar to urinary porphyrin excretion in PCT. The analysis of fecal porphyrins and the observation of fecal UP/PP and CP/PP ratios may be helpful in the biochemical diagnosis of PCT. In particular, the elevation of CP/PP ratio is characteristic of PCT.