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Parker CJ, Desnick RJ, Bissel MD, Bloomer JR, Singal A, Gouya L, Puy H, Anderson KE, Balwani M, Phillips JD. Results of a pilot study of isoniazid in patients with erythropoietic protoporphyria. Mol Genet Metab 2019; 128:309-313. [PMID: 31395332 PMCID: PMC6911826 DOI: 10.1016/j.ymgme.2019.07.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 07/29/2019] [Accepted: 07/30/2019] [Indexed: 01/13/2023]
Abstract
Erythropoietic protoporphyria (EPP), the most common porphyria of childhood and the third most common porphyria of adulthood, is characterized clinically by painful, non-blistering cutaneous photosensitivity. Two distinct inheritance patterns involving mutations affecting genes that encode enzymes of the heme biosynthetic pathway underlie the clinical phenotype. Aminolevulinic acid synthase 2 (ALAS2), the rate limiting enzyme of the heme pathway in the erythron, is a therapeutic target in EPP because inhibiting enzyme function would reduce downstream production of protoporphyrin IX (PPIX), preventing accumulation of the toxic molecule and thereby ameliorating symptoms. Isoniazid (INH) is widely used for treatment of latent and active M. tuberculosis (TB). Sideroblastic anemia is observed in some patients taking INH, and studies have shown that this process is a consequence of inhibition of ALAS2 by INH. Based on these observations, we postulated that INH might have therapeutic activity in patients with EPP. We challenged this hypothesis in a murine model of EPP and showed that, after 4 weeks of treatment with INH, both plasma PPIX and hepatic PPIX were significantly reduced. Next, we tested the effect of INH on patients with EPP. After eight weeks, no significant difference in plasma or red cell PPIX was observed among the 15 patients enrolled in the study. These results demonstrate that while INH can lower PPIX in an animal model of EPP, the standard dose used to treat TB is insufficient to affect levels in humans.
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Affiliation(s)
- Charles J Parker
- University of Utah School of Medicine, Salt Lake City, UT, United States of America
| | - Robert J Desnick
- Icahn School of Medicine at Mt. Sinai, New York, NY, United States of America
| | | | - Joseph R Bloomer
- University of Alabama at Birmingham, AL, United States of America
| | - Ashwani Singal
- University of Alabama at Birmingham, AL, United States of America
| | - Laurent Gouya
- Hôpitaux Universitaires Paris Nord Val de Seine, INSERM U1149 CNRS ERL 8252, Université Paris Diderot, Sorbonne Paris Cité, France
| | - Herve Puy
- Hôpitaux Universitaires Paris Nord Val de Seine, INSERM U1149 CNRS ERL 8252, Université Paris Diderot, Sorbonne Paris Cité, France
| | - Karl E Anderson
- University of Texas Medical Branch, Galveston, TX, United States of America
| | - Manisha Balwani
- Icahn School of Medicine at Mt. Sinai, New York, NY, United States of America
| | - John D Phillips
- University of Utah School of Medicine, Salt Lake City, UT, United States of America.
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Wang B, Balwani M, Bonkovsky HL, Anderson KE, Bloomer JR, Bissell DM, Phillips JD, Desnick RJ. Reply. Hepatology 2018; 67:803-804. [PMID: 29159969 DOI: 10.1002/hep.29674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 11/13/2017] [Indexed: 12/07/2022]
Affiliation(s)
- Bruce Wang
- Department of Medicine, University of California, San Francisco, CA
| | - Manisha Balwani
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Herbert L Bonkovsky
- Department of Medicine, Wake Forest Baptist Medical Center, Winston-Salem, NC
| | - Karl E Anderson
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX
| | | | | | - John D Phillips
- Department of Internal Medicine, University of Utah, Salt Lake City, UT
| | - Robert J Desnick
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY
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Balwani M, Wang B, Anderson KE, Bloomer JR, Bissell DM, Bonkovsky HL, Phillips JD, Desnick RJ. Acute hepatic porphyrias: Recommendations for evaluation and long-term management. Hepatology 2017; 66:1314-1322. [PMID: 28605040 PMCID: PMC5605422 DOI: 10.1002/hep.29313] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 05/10/2017] [Accepted: 06/08/2017] [Indexed: 12/12/2022]
Abstract
The acute hepatic porphyrias are a group of four inherited disorders, each resulting from a deficiency in the activity of a specific enzyme in the heme biosynthetic pathway. These disorders present clinically with acute neurovisceral symptoms which may be sporadic or recurrent and, when severe, can be life-threatening. The diagnosis is often missed or delayed as the clinical features resemble other more common medical conditions. There are four major subgroups: symptomatic patients with sporadic attacks (<4 attacks/year) or recurrent acute attacks (≥4 attacks/year), asymptomatic high porphyrin precursor excretors, and asymptomatic latent patients without symptoms or porphyrin precursor elevations. Given their clinical heterogeneity and potential for significant morbidity with suboptimal management, comprehensive clinical guidelines for initial evaluation, follow-up, and long-term management are needed, particularly because no guidelines exist for monitoring disease progression or response to treatment. The Porphyrias Consortium of the National Institutes of Health's Rare Diseases Clinical Research Network, which consists of expert centers in the clinical management of these disorders, has formulated these recommendations. These recommendations are based on the literature, ongoing natural history studies, and extensive clinical experience. Initial assessments should include diagnostic confirmation by biochemical testing, subsequent genetic testing to determine the specific acute hepatic porphyria, and a complete medical history and physical examination. Newly diagnosed patients should be counseled about avoiding known precipitating factors. The frequency of follow-up depends on the clinical subgroup, with close monitoring of patients with recurrent attacks who may require treatment modifications as well as those with clinical complications. Comprehensive care should include subspecialist referrals when needed. Annual assessments include biochemical testing and monitoring for long-term complications. These guidelines provide a framework for monitoring patients with acute hepatic porphyrias to ensure optimal outcomes. (Hepatology 2017;66:1314-1322).
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Affiliation(s)
- Manisha Balwani
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, NY, NY
| | - Bruce Wang
- Department of Medicine, University of California, San Francisco, CA
| | - Karl E. Anderson
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston, TX
| | | | | | - Herbert L. Bonkovsky
- Department of Medicine, Wake Forest NC Baptist Medical Center, Winston-Salem, NC
| | - John D. Phillips
- Department of Internal Medicine, University of Utah, Salt Lake City, UT
| | - Robert J. Desnick
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, NY, NY
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Gou EW, Balwani M, Bissell DM, Bloomer JR, Bonkovsky HL, Desnick RJ, Naik H, Phillips JD, Singal AK, Wang B, Keel S, Anderson KE. Pitfalls in Erythrocyte Protoporphyrin Measurement for Diagnosis and Monitoring of Protoporphyrias. Clin Chem 2015; 61:1453-6. [PMID: 26482161 DOI: 10.1373/clinchem.2015.245456] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2015] [Accepted: 08/31/2015] [Indexed: 01/18/2023]
Abstract
BACKGROUND Laboratory diagnosis of erythropoietic protoporphyria (EPP) requires a marked increase in total erythrocyte protoporphyrin (300-5000 μg/dL erythrocytes, reference interval <80 μg/dL) and a predominance (85%-100%) of metal-free protoporphyrin [normal, mostly zinc protoporphyrin (reference intervals for the zinc protoporphyrin proportion have not been established)]; plasma porphyrins are not always increased. X-linked protoporphyria (XLP) causes a similar increase in total erythrocyte protoporphyrin with a lower fraction of metal-free protoporphyrin (50%-85% of the total). CONTENT In studying more than 180 patients with EPP and XLP, the Porphyrias Consortium found that erythrocyte protoporphyrin concentrations for some patients were much higher (4.3- to 46.7-fold) than indicated by previous reports provided by these patients. The discrepant earlier reports, which sometimes caused the diagnosis to be missed initially, were from laboratories that measure protoporphyrin only by hematofluorometry, which is intended primarily to screen for lead poisoning. However, the instrument can calculate results on the basis of assumed hematocrits and reports results as "free" and "zinc" protoporphyrin (with different reference intervals), implying separate measurements of metal-free and zinc protoporphyrin. Such misleading reports impair diagnosis and monitoring of patients with protoporphyria. SUMMARY We suggest that laboratories should prioritize testing for EPP and XLP, because accurate measurement of erythrocyte total and metal-free protoporphyrin is essential for diagnosis and monitoring of these conditions, but less important for other disorders. Terms and abbreviations used in reporting erythrocyte protoporphyrin results should be accurately defined.
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Affiliation(s)
- Eric W Gou
- University of Texas Medical Branch, Galveston, TX
| | | | | | | | | | | | | | | | | | - Bruce Wang
- University of California at San Francisco, San Francisco, CA
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Butler DF, Ginn KF, Daniel JF, Bloomer JR, Kats A, Shreve N, Myers GD. Bone marrow transplant for X-linked protoporphyria with severe hepatic fibrosis. Pediatr Transplant 2015; 19:E106-10. [PMID: 25856424 DOI: 10.1111/petr.12472] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/13/2015] [Indexed: 11/27/2022]
Abstract
XLP is an erythroid porphyria that results in variable cutaneous photosensitivity due to accumulation of protoporphyrin. The genetic defect in XLP is mutation of the gene ALAS2, resulting in gain of function for the erythroid enzyme 5-aminolevulinate synthase 2. Previous reports have shown that protoporphyrin-induced liver disease may also occur in XLP, occasionally severe enough to warrant liver transplantation; however, transplantation may be followed by injury to the graft due to continued presence of the underlying metabolic disorder in the bone marrow. We present a case of XLP with severe liver disease successfully treated with HPCT to avoid liver transplantation. The case also demonstrates the feasibility of reduced intensity transplant to provide engraftment sufficient for correction of porphyria and tolerability of reduced intensity conditioning containing TLI in the face of severe liver injury.
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Affiliation(s)
- David F Butler
- Department of Pediatrics, Childrens Mercy Hospital, Kansas City, MO, USA
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Bloomer JR, Hill HD, Kools AM, Straka JG. Heme Synthesis in Protoporphyria1. Metabolic Disorders and Nutrition Correlated with Skin 2015. [DOI: 10.1159/000420017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Raff EJ, Kakati D, Bloomer JR, Shoreibah M, Rasheed K, Singal AK. Diabetes Mellitus Predicts Occurrence of Cirrhosis and Hepatocellular Cancer in Alcoholic Liver and Non-alcoholic Fatty Liver Diseases. J Clin Transl Hepatol 2015; 3:9-16. [PMID: 26356325 PMCID: PMC4542082 DOI: 10.14218/jcth.2015.00001] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/19/2015] [Accepted: 02/22/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND AIMS Alcohol abuse and nonalcoholic fatty liver disease (NAFLD) are common causes of liver disease. Diabetes mellitus (DM) is a common comorbidity among NAFLD patients. We performed this study with the specific aim to examine the impact of DM on progression of alcoholic liver disease (ALD) liver and NAFLD. METHODS Medical charts of 480 patients with ALD or NAFLD (2004-2011) managed at a tertiary center were retrospectively reviewed. NAFLD was diagnosed based on exclusion of other causes of liver disease and alcohol use of <10 g/d. ALD was diagnosed based on alcohol use of >40 g/d in women or >60 g/d in men for >5 years. RESULTS Of 480 patients (307 NAFLD), 200 diabetics differed from nondiabetics for: age (52±11 vs. 49±11 years; p=0.004); male gender (48% vs. 57%; p=0.03); metabolic syndrome (49% vs. 30%; p=0.0002); NAFLD (80% vs. 56%; p<0.0001); cirrhosis (70% vs. 59%; p=0.005); and hepatocellular carcinoma (HCC; 8% vs. 3%; p=0.009). Over a 3 year median follow-up period, diabetics relative to nondiabetics had a higher probability to develop cirrhosis (60% vs. 41%; p=0.022) and HCC (27% vs. 10%; p=0.045). There was a trend for increased development of hepatic encephalopathy in diabetics compared to nondiabetics (55% vs. 39%; p=0.053), and there was no difference between the two groups in survival or other liver disease complications. CONCLUSIONS DM increased risk for cirrhosis and HCC among patients with ALD and NAFLD. Prospective studies with longer follow-up periods are needed to examine the impact of DM on survival and the role of aggressive HCC screening in diabetic cirrhotics.
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Affiliation(s)
- Evan J. Raff
- Department of Internal Medicine, UAB, Birmingham, AL, USA
| | - Donny Kakati
- Department of Internal Medicine, UAB, Birmingham, AL, USA
| | - Joseph R. Bloomer
- Division of Gastroenterology and Hepatology, UAB, Birmingham, AL, USA
| | - Mohamed Shoreibah
- Division of Gastroenterology and Hepatology, UAB, Birmingham, AL, USA
| | - Khalid Rasheed
- Department of Internal Medicine, UAB Montgomery Program, Huntsville, AL, USA
| | - Ashwani K. Singal
- Division of Gastroenterology and Hepatology, UAB, Birmingham, AL, USA
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Bonkovsky HL, Maddukuri VC, Yazici C, Anderson KE, Bissell DM, Bloomer JR, Phillips JD, Naik H, Peter I, Baillargeon G, Bossi K, Gandolfo L, Light C, Bishop D, Desnick RJ. Acute porphyrias in the USA: features of 108 subjects from porphyrias consortium. Am J Med 2014; 127:1233-41. [PMID: 25016127 PMCID: PMC4563803 DOI: 10.1016/j.amjmed.2014.06.036] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 06/29/2014] [Accepted: 06/30/2014] [Indexed: 12/17/2022]
Abstract
BACKGROUND Recent descriptions of the clinical and laboratory features of subjects with acute porphyrias in the US are lacking. Our aim was to describe clinical, biochemical, and genetic features of 108 subjects. METHODS Between September 2010 and December 2012, 108 subjects with acute porphyrias (90 acute intermittent porphyrias, 9 hereditary coproporphyrias, 9 variegate porphyrias) were enrolled into an observational study. Genetic testing was performed at a central genetic testing laboratory and clinical information entered into a central database. Selected features were compared with data for adults in the US. RESULTS Most subjects (88/108, 81%) were female, with self-reported onset of symptoms in the second through fourth decades of life. The most common symptom was abdominal pain. Appendectomies and cholecystectomies were common before a diagnosis of porphyria. The diagnosis was delayed by a mean of 15 years. Anxiety and depression were common, and 18% complained of chronic symptoms, especially neuropathic and other pains. The incidences of systemic arterial hypertension, chronic kidney disease, seizure disorders, and psychiatric conditions were markedly increased. Mutations of the known causative genes were found in 102/105 of those tested, with novel mutations being found in 37, including in 7/8 subjects with hereditary coproporphyria. Therapy with intravenous hematin was the most effective therapy both for treatment of acute attacks and for prevention of recurrent attacks. CONCLUSIONS Acute porphyrias often remain undiagnosed for more than a decade after first symptoms develop. Intravenous hematin is the treatment of choice, both for treatment of acute attacks and for prevention of recurrent attacks.
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MESH Headings
- Adult
- Anxiety/epidemiology
- Coproporphyria, Hereditary/diagnosis
- Coproporphyria, Hereditary/epidemiology
- Coproporphyria, Hereditary/genetics
- Delayed Diagnosis
- Depression/epidemiology
- Epilepsy/epidemiology
- Female
- Humans
- Hypertension/epidemiology
- Incidence
- Male
- Middle Aged
- Neuralgia/epidemiology
- Porphyria, Acute Intermittent/diagnosis
- Porphyria, Acute Intermittent/epidemiology
- Porphyria, Acute Intermittent/genetics
- Porphyria, Variegate/diagnosis
- Porphyria, Variegate/epidemiology
- Porphyria, Variegate/genetics
- Renal Insufficiency, Chronic/epidemiology
- Sex Distribution
- United States/epidemiology
- Young Adult
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Affiliation(s)
- Herbert L Bonkovsky
- The Liver-Biliary-Pancreatic Center, Carolinas HealthCare System, Charlotte, NC; Department of Medicine, Carolinas HealthCare System, Charlotte, NC; Department of Research, Carolinas HealthCare System, Charlotte, NC.
| | - Vinaya C Maddukuri
- The Liver-Biliary-Pancreatic Center, Carolinas HealthCare System, Charlotte, NC; Department of Medicine, Carolinas HealthCare System, Charlotte, NC; Department of Research, Carolinas HealthCare System, Charlotte, NC
| | - Cemal Yazici
- The Liver-Biliary-Pancreatic Center, Carolinas HealthCare System, Charlotte, NC; Department of Medicine, Carolinas HealthCare System, Charlotte, NC; Department of Research, Carolinas HealthCare System, Charlotte, NC
| | - Karl E Anderson
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston
| | | | | | - John D Phillips
- Department of Medicine, University of Utah School of Medicine, Salt Lake City
| | - Hetanshi Naik
- Department of Genetics & Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Inga Peter
- Department of Genetics & Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Gwen Baillargeon
- Department of Preventive Medicine and Community Health, University of Texas Medical Branch, Galveston
| | - Krista Bossi
- Department of Research, Carolinas HealthCare System, Charlotte, NC
| | | | | | - David Bishop
- Department of Genetics & Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Robert J Desnick
- Department of Genetics & Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY
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Melia MT, Muir AJ, McCone J, Shiffman ML, King JW, Herrine SK, Galler GW, Bloomer JR, Nunes FA, Brown KA, Mullen KD, Ravendhran N, Ghalib RH, Boparai N, Jiang R, Noviello S, Brass CA, Albrecht JK, McHutchison JG, Sulkowski MS. Racial differences in hepatitis C treatment eligibility. Hepatology 2011; 54:70-8. [PMID: 21488082 PMCID: PMC3736356 DOI: 10.1002/hep.24358] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
UNLABELLED Black Americans are disproportionally infected with hepatitis C virus (HCV) and are less likely than whites to respond to treatment with peginterferon (PEG-IFN) plus ribavirin (RBV). The impact of race on HCV treatment eligibility is unknown. We therefore performed a retrospective analysis of a phase 3B multicenter clinical trial conducted at 118 United States community and academic medical centers to evaluate the rates of and reasons for HCV treatment ineligibility according to self-reported race. In all, 4,469 patients were screened, of whom 1,038 (23.2%) were treatment ineligible. Although blacks represented 19% of treated patients, they were more likely not to be treated due to ineligibility and/or failure to complete required evaluations (40.2%) than were nonblack patients (28.5%; P < 0.001). After the exclusion of persons not treated due to undetectable HCV RNA or nongenotype 1 infection, blacks were 65% less likely than nonblacks to be eligible for treatment (28.1% > 17.0%; relative risk, 1.65; 95% confidence interval, 1.46-1.87; P < 0.001). Blacks were more likely to be ineligible due to neutropenia (14% versus 3%, P < 0.001), anemia (7% versus 4%, P = 0.02), elevated glucose (8% versus 3%, P < 0.001), and elevated creatinine (5% versus 1%, P < 0.001). CONCLUSION Largely due to a higher prevalence of neutropenia and uncontrolled medical conditions, blacks were significantly less likely to be eligible for HCV treatment. Increased access to treatment may be facilitated by less conservative neutrophil requirements and more effective care for chronic diseases, namely, diabetes and renal insufficiency.
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Affiliation(s)
| | - Andrew J. Muir
- Duke Clinical Research Institute and Division of Gastroenterology, Duke University, Durham, NC
| | | | | | - John W. King
- Louisiana State University Health Sciences Center, Shreveport, LA
| | | | | | | | | | | | | | | | | | - Navdeep Boparai
- Schering-Plough Research Institute, now Merck Research Laboratories, Kenilworth, NJ
| | - Ruiyun Jiang
- Schering-Plough Research Institute, now Merck Research Laboratories, Kenilworth, NJ
| | - Stephanie Noviello
- Schering-Plough Research Institute, now Merck Research Laboratories, Kenilworth, NJ
| | - Clifford A. Brass
- Schering-Plough Research Institute, now Merck Research Laboratories, Kenilworth, NJ
| | - Janice K. Albrecht
- Schering-Plough Research Institute, now Merck Research Laboratories, Kenilworth, NJ
| | - John G. McHutchison
- Duke Clinical Research Institute and Division of Gastroenterology, Duke University, Durham, NC
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Affiliation(s)
- Joseph R Bloomer
- Liver Center and Division of Gastroenterology/Hepatology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294-0005, USA.
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Rand EB, Bunin N, Cochran W, Ruchelli E, Olthoff KM, Bloomer JR. Sequential liver and bone marrow transplantation for treatment of erythropoietic protoporphyria. Pediatrics 2006; 118:e1896-9. [PMID: 17074841 DOI: 10.1542/peds.2006-0833] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Erythropoietic protoporphyria is a disorder of heme synthesis in which deficient ferrochelatase activity leads to excess production and biliary excretion of protoporphyrin. The main clinical features, photosensitivity and hepatobiliary disease that may progress to liver failure, are caused by the toxicity of protoporphyrin. Liver transplantation has been used to treat liver failure in erythropoietic protoporphyria, but excess production of protoporphyrin by the bone marrow continues causing recurrence of liver disease in the majority of patients. This is the first report of successful sequential liver and bone marrow transplantation in a patient with liver failure as a result of erythropoietic protoporphyria. This combination corrected the severe phenotype, resolving the severe photosensitivity and halting erythropoietic protoporphyria associated liver graft injury. Splenectomy seemed to facilitate the successful bone marrow transplant.
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Affiliation(s)
- Elizabeth B Rand
- Department of Pediatrics, University of Pennsylvania, Children's Hospital of Philadelphia, 324 S 34th St, Philadelphia, PA 19104, USA.
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Abstract
OBJECTIVES Erythropoietic protoporphyria (EPP) is a genetic disorder in which deficient ferrochelatase (FECH) activity causes the excessive production and excretion of protoporphyrin. This in turn causes the major clinical manifestation of EPP, photosensitivity and, in some patients, hepatobiliary disease that may be severe. The objective of this study was to define genotypic determinants of phenotype in EPP. METHODS FECH activity was measured in 30 tissue samples from 26 patients with symptomatic EPP to determine the degree of deficient activity. FECH DNA analysis was also done in 26 families with EPP to identify mutations and examine for the presence of a polymorphism (IVS3-48c) that causes low gene expression. RESULTS The level of residual FECH activity that was measured in tissue samples of patients with symptomatic EPP was <or=30% of the mean normal level in all patients except one. Lowest levels (4-20% normal) were in patients with advanced EPP liver disease. Heterozygous FECH mutations were found in 45 individuals from 26 families with EPP. In 94% of the 32 symptomatic individuals, 15 of whom had liver disease, the polymorphism was present in the nonmutant allele. In 13 asymptomatic patients, the polymorphism was absent. CONCLUSIONS Patients with symptomatic EPP (photosensitivity with/without hepatobiliary disease) usually have a mutation in 1 FECH allele that alters enzyme structure/function, together with a polymorphism in the nonmutant allele that causes low gene expression. This leads to a significant reduction in FECH activity that causes symptomatic disease to develop because of the excess protoporphyrin produced.
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Affiliation(s)
- Joseph R Bloomer
- Department of Medicine, Liver Center, University of Alabama at Birmingham, 35294-0005, USA.
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McGuire BM, Bonkovsky HL, Carithers RL, Chung RT, Goldstein LI, Lake JR, Lok AS, Potter CJ, Rand E, Voigt MD, Davis PR, Bloomer JR. Liver transplantation for erythropoietic protoporphyria liver disease. Liver Transpl 2005; 11:1590-6. [PMID: 16315313 DOI: 10.1002/lt.20620] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
In erythropoietic protoporphyria (EPP), there is excessive production of protoporphyrin, primarily in the bone marrow, resulting in increased biliary excretion of this heme precursor. Some patients will develop progressive liver disease that may ultimately require liver transplantation. However, excessive production of protoporphyrin by the bone marrow continues after transplantation, which may cause recurrent disease in the allograft. This study was performed to define post-transplant survival, the risk of recurrent disease, and specific management issues in patients transplanted for EPP liver disease. The patients studied consisted of twelve males and eight females, with an average age of 31 (range, 13-56) years at the time of transplantation. The estimated maximum MELD score prior to transplant was 21 (range, 15-29). Unique complications in the perioperative period were light induced tissue damage in four patients and neuropathy in six, requiring prolonged mechanical ventilation in four. Patient and graft survival rates were 85% at 1 year, 69% at 5 years, and 47% at 10 years. Recurrent EPP liver disease occurred in 11 of 17 patients (65%) who survived more than 2 months. Three patients were retransplanted at 1.8, 12.6, and 14.5 years after the initial transplant for recurrent EPP liver disease. In conclusion, the 5-year patient survival rate in patients transplanted for EPP liver disease is good, but the recurrence of EPP liver disease appears to diminish long term graft and patient survival.
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Affiliation(s)
- Brendan M McGuire
- Department of Medicine, University of Alabama at Birmingham, 1530 Third Avenue South, Birmingham, AL 35294-0005, USA.
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Abstract
The acute porphyrias, 4 inherited disorders of heme biosynthesis, cause life-threatening attacks of neurovisceral symptoms that mimic many other acute medical and psychiatric conditions. Lack of clinical recognition often delays effective treatment, and inappropriate diagnostic tests may lead to misdiagnosis and inappropriate treatment. We review the clinical manifestations, pathophysiology, and genetics of the acute porphyrias and provide recommendations for diagnosis and treatment on the basis of reviews of the literature and clinical experience. An acute porphyria should be considered in many patients with unexplained abdominal pain or other characteristic symptoms. The diagnosis can be rapidly confirmed by demonstration of a markedly increased urinary porphobilinogen level by using a single-void urine specimen. This specimen should also be saved for quantitative measurement of porphobilinogen, 5-aminolevulinic acid, and total porphyrin levels. Intravenous hemin therapy, started as soon as possible, is the most effective treatment. Intravenous glucose alone is appropriate only for mild attacks (mild pain, no paresis or hyponatremia) or until hemin is available. Precipitating factors should be eliminated, and appropriate supportive and symptomatic therapy should be initiated. Prompt diagnosis and treatment greatly improve prognosis and may prevent development of severe or chronic neuropathic symptoms. We recommend identification of at-risk relatives through enzymatic or gene studies.
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Abstract
Ferrochelatase (FECH), the last enzyme of the heme biosynthetic pathway, catalyzes the insertion of iron into protoporphyrin to form heme. This pathway provides heme for hemoglobin and other essential hemoproteins. The regulatory role of oxygen in the pathway has not been clearly established. In this study, we examined whether FECH gene expression is upregulated during hypoxia by a mechanism which involves the hypoxia-inducible factor 1 (HIF-1). Two HIF-1 binding motifs were identified within the -150 bp FECH minimal promoter sequence. Exposure of HEL, K562, and Hep-G2 cells to hypoxia for 18 hours resulted in a significant increase in FECH mRNA expression (p < 0.05). Hypoxia also transactivated the minimal promoter for the FECH gene in the cells. Transient co-expression of wild-type HIF-1alpha or a dominant negative HIF-1alpha with the FECH minimal promoter luciferase construct stimulated or blocked FECH promoter activity, respectively. Expression of the von Hippel-Lindau (VHL) tumor suppressor factor blocked the expression of both FECH mRNA and HIF-1alpha protein during normoxic culture of renal carcinoma cell line (RCC4). The results suggest that the FECH gene is a target for HIF-1 during hypoxia.
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Affiliation(s)
- Yunying L Liu
- Department of Medicine, Liver Center, University of Alabama at Birmingham, 35294-0005, USA
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18
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Abstract
Erythropoietic protoporphyria (EPP) is characterized by excess accumulation of protoporphyrin, which is due to deficient activity of the enzyme ferrochelatase (FECH). This results in photosensitivity and in some patients liver disease which may necessitate liver transplantation. The aim of this study was to delineate the abnormalities in the FECH gene which cause phenotypic expression in EPP. We identified 43 individuals from 25 North American families with EPP who were heterozygous for various FECH mutations, but the mutations did not adequately explain the variable phenotype. We also examined the presence of an intron polymorphism (IVS3-48c) in the FECH gene which was shown to cause the formation of aberrantly spliced FECH mRNA. FECH DNA analysis demonstrated that 94% of 31 symptomatic individuals with FECH mutations were heterozygous for IVS3-48c, whereas 12 asymptomatic individuals with FECH mutations were homozygous for IVS3-48t. Haplotype analysis in four families showed that symptomatic members had the IVS3-48c polymorphism in the non-mutant FECH allele. Sequencing of the proximal FECH gene promoter showed no additional changes which might affect gene expression. The levels of normal FECH mRNA, measured by relative quantitative RT-PCR, and FECH enzyme activity were correspondingly lower in the cultured lymphoblasts of family members with the IVS3-48c polymorphism. These results indicate that symptomatic disease in most North American patients with EPP is explained by the inheritance of a mutation in one FECH allele which causes a structural alteration in the protein, together with a low expressing non-mutant FECH allele which is caused by the IVS3-48c polymorphism.
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Affiliation(s)
- Hiba Risheg
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
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19
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Poh-Fitzpatrick MB, Wang X, Anderson KE, Bloomer JR, Bolwell B, Lichtin AE. Erythropoietic protoporphyria: altered phenotype after bone marrow transplantation for myelogenous leukemia in a patient heteroallelic for ferrochelatase gene mutations. J Am Acad Dermatol 2002; 46:861-6. [PMID: 12063482 DOI: 10.1067/mjd.2002.120460] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acute myelogenous leukemia occurred in a 47-year-old woman whose 25-year history of cutaneous photosensitivity had been undiagnosed until abnormally high erythrocyte, plasma, and fecal protoporphyrin levels were discovered during evaluation for her hematologic disorder. She was found to be heteroallelic for ferrochelatase gene mutations, bearing a novel missense mutation caused by a C185-->G (Pro62-->Arg) transversion in exon 2 of one allele, and a previously described g-->a transition at the +5 position of the exon 1 donor site of the other allele, confirming a diagnosis of erythropoietic protoporphyria. Successful bone marrow transplantation from her brother, who is a mildly affected bearer of the second mutation, resulted in remission of the leukemia and in conversion of the protoporphyria phenotype of the recipient to one resembling that of the donor.
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MESH Headings
- Bone Marrow Transplantation
- DNA Primers
- Female
- Ferrochelatase/genetics
- Humans
- Leukemia, Myelomonocytic, Acute/complications
- Leukemia, Myelomonocytic, Acute/therapy
- Middle Aged
- Mutation
- Pedigree
- Phenotype
- Polymerase Chain Reaction
- Polymorphism, Restriction Fragment Length
- Porphyria, Hepatoerythropoietic/complications
- Porphyria, Hepatoerythropoietic/diagnosis
- Porphyria, Hepatoerythropoietic/genetics
- Porphyria, Hepatoerythropoietic/pathology
- Porphyria, Hepatoerythropoietic/therapy
- Porphyrins/blood
- Porphyrins/metabolism
- Porphyrins/urine
- Protoporphyrins/blood
- Protoporphyrins/metabolism
- Protoporphyrins/urine
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Affiliation(s)
- Maureen B Poh-Fitzpatrick
- Department of Dermatology, Columbia University College of Physicians and Surgeons, New York, New York, USA
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20
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Dellon ES, Szczepiorkowski ZM, Dzik WH, Graeme-Cook F, Ades A, Bloomer JR, Cosimi AB, Chung RT. Treatment of recurrent allograft dysfunction with intravenous hematin after liver transplantation for erythropoietic protoporphyria. Transplantation 2002; 73:911-5. [PMID: 11923691 DOI: 10.1097/00007890-200203270-00014] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Erythropoietic protoporphyria (EPP) is a rare inherited disorder of the heme biosynthetic pathway in which toxic levels of protoporphyrins often precipitate in the liver, leading to cirrhosis, liver failure, and the need for liver transplantation (OLT). Because the underlying enzyme defect in EPP is bone marrow derived, the risk for recurrent EPP allograft dysfunction is high. Although plasmapheresis may ameliorate acute allograft disease, strategies to maintain disease remission are needed. A 59-year-old man who underwent OLT for hepatic EPP experienced increased bilirubin and aminotransferases on postoperative day 700. Allograft biopsy demonstrated recurrent EPP. He was managed initially with plasmapheresis, hypertransfusion, and infusions of i.v. hematin. After normalization of liver tests, the hematin infusions have been given intermittently, are well tolerated, and associated with normal allograft function for nearly 2 years. This is the first case of the use of hematin given post-OLT to help achieve and maintain remission of allograft EPP disease.
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Affiliation(s)
- Evan S Dellon
- Medical Service (Gastrointestinal Unit), Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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21
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Affiliation(s)
- Hugo R Rosen
- Liver and Intra-Abdominal Subcommittee, American Society for Transplantation, USA.
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22
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23
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Bloomer JR, Poh-Fitzpatrick MB. Theodore Woodward Award. Pathogenesis of biochemical abnormalities in protoporphyria. Trans Am Clin Climatol Assoc 2000; 111:245-257. [PMID: 10881344 PMCID: PMC2194363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In summary, FC gene mutations in patients with protoporphyric liver disease typically cause major structural alterations in the FC protein. However, the gene mutations by themselves do not satisfactorily account for the severe phenotype, as the same mutations are found in asymptomatic family members, and similar mutations are found in patients who do not develop liver disease. Thus there may be unidentified factors in the FC gene locus, or factors outside the locus, which are also important in determining the degree of protoporphyrin accumulation that occurs in an individual patient, hence, the potential for developing significant liver disease. Further studies are needed to clarify this possibility and identify those factors.
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Affiliation(s)
- J R Bloomer
- Department of Medicine, University of Alabama at Birmingham, USA
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24
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Abrams GA, Rose K, Fallon MB, McGuire BM, Bloomer JR, van Leeuwen DJ, Tutton T, Sellers MT, Eckhoff DE, Bynon JS. Hepatopulmonary syndrome and venous emboli causing intracerebral hemorrhages after liver transplantation: a case report. Transplantation 1999; 68:1809-11. [PMID: 10609961 DOI: 10.1097/00007890-199912150-00028] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Increasing experience has fostered the acceptance of liver transplantation as a treatment for patients with hepatopulmonary syndrome. Morbidity and mortality is most commonly attributed to progressive arterial hypoxemia postoperatively. A cerebral hemorrhage has been reported in one patient with hepatopulmonary syndrome after transplantation. However, a postmortem examination of the brain was not performed and the pathogenesis or type of cerebral hemorrhage was undefined. We report on a patient with severe hepatopulmonary syndrome who developed multiple intracranial hemorrhages after transplantation. The intracerebral hemorrhages were most consistent with an embolic etiology on postmortem examination. We postulate that venous embolization, caused by the manipulation of a Swan Ganz catheter in a thrombosed central vein, resulted in pulmonary emboli that passed through dilated intrapulmonary vessels into the cerebral microcirculation. Special attention to central venous catheters and avoidance of manipulation may be warranted in subjects with severe hepatopulmonary syndrome after liver transplantation.
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Affiliation(s)
- G A Abrams
- Division of Gastroenterology and Hepatology, Liver Center, University of Alabama at Birmingham, 35294-0007, USA
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25
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Jenkins MM, LeBoeuf RD, Ruth GR, Bloomer JR. A novel stop codon mutation (X417L) of the ferrochelatase gene in bovine protoporphyria, a natural animal model of the human disease. Biochim Biophys Acta 1998; 1408:18-24. [PMID: 9784594 DOI: 10.1016/s0925-4439(98)00052-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Protoporphyria (PP) is caused by a deficiency of ferrochelatase (FC) activity, which catalyzes the final step in the heme biosynthesis pathway. Bovine are the only species other than man with naturally occurring PP. For expression of the PP phenotype, two copies of the mutated gene are necessary in bovine, whereas one copy is sufficient in humans. We report the first potential disease-causing mutation in the bovine FC gene. The coding region of FC was sequenced from the liver tissue of protoporphyric and normal bovine. A transversion was identified at nucleotide position 1250 which changed the stop codon to leucine (TGA-->TTA) in the protoporphyric FC sequence. As a consequence, the mutant protein is predicted to have an additional 27 amino acids. To screen other bovine for the G-->T transversion, cDNAs from liver tissue of clinically and biochemically normal, and from heterozygous and homozygous affected animals were used for allele-specific polymerase chain reaction. Three normal animals had only the G allele, five affected animals had only the T allele, and three heterozygous animals had both the G and T alleles. These results support our hypothesis that this mutation causes PP in bovine.
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Affiliation(s)
- M M Jenkins
- Department of Medicine and Liver Center, University of Alabama at Birmingham, Basic Health Science Building 395, 1918 University Boulevard, Birmingham, AL 35294-0005, USA
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26
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Abstract
The liver is an active site for the biosynthesis of haem and porphyrinogens/porphyrins, which are intermediates of the haem biosynthetic pathway, because haem is required for functional activity of the cytochrome P 450 system and other critical hepatic haemoproteins. The production of hepatic haem is regulated primarily through the activity of aminolaevulinic acid synthase which is the first and normally rate-limiting enzyme of the pathway. This is, in turn, controlled by a putative regulatory haem pool. Hepatic haem can be repleted by the intravenous administration of haem, which is the basis for haem therapy in patients with acute porphyric attacks. The liver catabolizes haem to bilirubin through microsomal haem oxygenase activity and excretes haem into bile along with porphyrins. Biliary excretion of porphyrins increases significantly in patients with some types of porphyria. In protoporphyria this may cause liver damage as a result of protoporphyrin toxicity. The delineation of the pathway for protoporphyrin excretion into bile should facilitate therapy in protoporphyria by identifying ways in which protoporphyrin excretion can be enhanced.
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Affiliation(s)
- J R Bloomer
- The Liver Center, University of Alabama, Birmingham 35294-0005, USA
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27
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Abstract
The porphyrias are metabolic disorders characterized by abnormal heme biosynthesis with excessive accumulation and excretion of porphyrias or porphyrin precursors. Defects in the enzymes of the heme biosynthetic pathway result in porphyria. Several of the disorders have been classified as hepatic because the major site of the biochemical defect has been localized to the liver. This article describes the enzymes of the heme biosynthetic pathway, the clinical features of the hepatic porphyrias and management of the disorders.
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Affiliation(s)
- Y V Scarlett
- Division of Digestive Diseases and Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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28
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Abstract
Cirrhosis is a chronic disease of the liver in which dense bands of fibrosis enclose regenerative hepatocellular nodules. Clinical and radiologic features of advanced liver disease provide presumptive evidence for the presence of cirrhosis. Major complications are related to the increased hepatic resistance, increased sodium and water retention, and hyperdynamic changes of the circulatory system. Patient management should consist of appropriate prophylaxis for the life-threatening complications of variceal bleeding and spontaneous bacterial peritonitis and treatment of other complications as signs and symptoms develop.
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Affiliation(s)
- B M McGuire
- Liver Center, University of Alabama at Birmingham 35294-0005, USA.
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29
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Daniell WE, Stockbridge HL, Labbe RF, Woods JS, Anderson KE, Bissell DM, Bloomer JR, Ellefson RD, Moore MR, Pierach CA, Schreiber WE, Tefferi A, Franklin GM. Environmental chemical exposures and disturbances of heme synthesis. Environ Health Perspect 1997; 105 Suppl 1:37-53. [PMID: 9114276 PMCID: PMC1470308 DOI: 10.1289/ehp.97105s137] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Porphyrias are relatively uncommon inherited or acquired disorders in which clinical manifestations are attributable to a disturbance of heme synthesis (porphyrin metabolism), usually in association with endogenous or exogenous stressors. Porphyrias are characterized by elevations of heme precursors in blood, urine, and/or stool. A number of chemicals, particularly metals and halogenated hydrocarbons, induce disturbances of heme synthesis in experimental animals. Certain chemicals have also been linked to porphyria or porphyrinuria in humans, generally involving chronic industrial exposures or environmental exposures much higher than those usually encountered. A noteworthy example is the Turkish epidemic of porphyria cutanea tarda produced by accidental ingestion of wheat treated with the fungicide hexachlorobenzene. Measurements of excreted heme precursors have the potential to serve as biological markers for harmful but preclinical effects of certain chemical exposures; this potential warrants further research and applied field studies. It has been hypothesized that several otherwise unexplained chemical-associated illnesses, such as multiple chemical sensitivity syndrome, may represent mild chronic cases of porphyria or other acquired abnormalities in heme synthesis. This review concludes that, although it is reasonable to consider such hypotheses, there is currently no convincing evidence that these illnesses are mediated by a disturbance of heme synthesis; it is premature or unfounded to base clinical management on such explanations unless laboratory data are diagnostic for porphyria. This review discusses the limitations of laboratory measures of heme synthesis, and diagnostic guidelines are provided to assist in evaluating the symptomatic individual suspected of having a porphyria.
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Affiliation(s)
- W E Daniell
- Department of Environmental Health, University of Washington, Seattle 98195-7234, USA.
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30
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Bloomer JR. Hepatic protoporphyrin metabolism in patients with advanced protoporphyric liver disease. Yale J Biol Med 1997; 70:323-30. [PMID: 9626752 PMCID: PMC2589331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Protoporphyria is a genetic disorder in which liver damage is caused by the toxic effect of protoporphyrin accumulation in the liver. In this study protoporphyrin was measured in the resected livers of 7 patients who had liver transplantation and an additional patient from whom liver tissue was obtained post mortem. Comparison of liver, erythrocyte and serum protoporphyrin levels demonstrated a marked gradient between these compartments: erythrocyte, 5781 +/- 655 micrograms/dl; serum, 384 +/- 102 micrograms/dl; liver 377,238 +/- 55,568 micrograms/100 gm wet weight, (mean +/- SE). Protoporphyrin levels in bile of 3 patients were 55,559, and 1,153 micrograms/dl, indicating a gradient between liver and bile as well. Examination of the livers by polarization microscopy and electron microscopy demonstrated protoporphyrin pigment crystals. In one patient who had recurrent liver disease after transplantation, the protoporphyrin concentration in the graft at the time of death was similar to that in the resected liver. These data indicate that liver protoporphyrin levels in patients with advanced protoporphyric liver disease are much higher than levels in blood and bile, in part because protoporphyrin forms crystalline deposits in liver tissue. Thus, progressive hepatic accumulation of protoporphyrin occurs in the face of impaired biliary excretion. An intrinsic defect in hepatic excretion of protoporphyrin is probably not necessary for this condition to develop because liver disease can occur in the graft following transplantation.
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Affiliation(s)
- J R Bloomer
- UAB Liver Center, University of Alabama at Birmingham, USA.
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31
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Jeans JB, Savik K, Gross CR, Weimer MK, Bossenmaier IC, Pierach CA, Bloomer JR. Mortality in patients with acute intermittent porphyria requiring hospitalization: a United States case series. Am J Med Genet 1996; 65:269-73. [PMID: 8923933 DOI: 10.1002/(sici)1096-8628(19961111)65:4<269::aid-ajmg4>3.0.co;2-k] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Acute intermittent porphyria (AIP) is a genetic disorder in which patients may have life threatening attacks of neurologic dysfunction. This study examined the prognosis during the past 50 years of patients in the United States who required hospitalization for porphyric attacks. The cumulative survival was determined for 136 patients with AIP who were hospitalized for porphyric attacks between 1940 and 1988. Diagnosis was established on the basis of clinical symptoms, in combination with increased urinary excretion of porphobilinogen. The patient group had an average age of 32 years (range 9 to 75) at diagnosis and consisted of 43 males and 93 females. At follow-up, 19 males (44%) and 31 females (33%) were decreased. The standardized mortality ratio for the 136 patients, compared to an age-matched hypothetical population experiencing USA 1970 Census Death Rates was 3.2, with a 95% confidence interval of 2.4-4.0. Most deaths occurred during the initial porphyric attack (20% of deaths) or a subsequent attack (38% of deaths). Suicide was also common (five deaths). Comparison was made between 50 patients who were diagnosed before 1971, the year in which hematin therapy became available, and 86 patients who were diagnosed afterward. There was improved survival in the latter group, particularly after 10 years from the time of diagnosis, but this did not reach statistical significance. In conclusion, the proportionate increase in mortality due to symptomatic AIP was three-fold compared to the general population during the past 50 years. The major cause of the increased mortality was the porphyric attack itself.
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Affiliation(s)
- J B Jeans
- Watson Laboratory, University of Minnesota, Minneapolis, USA
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32
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Bloomer JR, Rank JM, Payne WD, Snover DC, Sharp HL, Zwiener RJ, Carithers RL. Follow-up after liver transplantation for protoporphyric liver disease. Liver Transpl Surg 1996; 2:269-75. [PMID: 9346660 DOI: 10.1002/lt.500020404] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Protoporphyria is a genetic disorder in which patients may develop severe protoporphyrin-induced liver damage and require transplantation. Because unique problems occur in the perioperative period and because excess production of protoporphyrin by the bone marrow continues after liver transplantation, the efficacy of this procedure for protoporphyric liver disease is uncertain. We present follow-up of nine patients who underwent liver transplantation. Two patients died within 2 months of transplantation, one from complications of abdominal bleeding and the other from sepsis after bowel perforations. The remaining seven patients had follow-up at 14 months to 8 years after transplantation (mean, 3.8 years). Two of the seven had suffered skin burns from exposure to operating room lights, which healed without scarring. Three had axonal neuropathies in the postoperative period requiring prolonged mechanical ventilation, and motor defects persisted in two. Five patients had normal liver chemistries at follow-up (mean, 3.5 years), with liver biopsy results normal or showing mild portal triad abnormalities, but erythrocyte protoporphyrin levels remained significantly elevated (1,765 +/- 365 mcg/dL; normal, < 65). The other two patients, both of whom had rejection, cytomegalovirus infection, and biliary tract obstruction requiring endoscopic therapy, had a recurrence of protoporphyric liver disease as indicated by liver biopsy features. One died 5 years after transplantation from complications of the liver disease. The other was stable 3.3 years after transplantation and was being monitored for possible retransplantation. Thus, liver transplantation can be performed successfully in patients with protoporphyric liver disease, with intermediate survival rates comparable to the general transplant population. However, disease may recur in the graft, particularly if there are complications that cause cholestasis.
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LaRusso NF, Phillips SF, Bloomer JR, Boland CR, Chang EB, DiMagno EP, Giannella RA, Gores GJ, Malagelada JR, Miller LJ, Rakela J, Szurszewski JH, Binder HJ, Clain JE, LaMont JT, Link AM. Passing the torch: a look back at our editorship. Gastroenterology 1996; 110:1336-8. [PMID: 8613036 DOI: 10.1053/gast.1996.v110.agast961336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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34
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Sielaff TD, Hu MY, Amiot B, Rollins MD, Rao S, McGuire B, Bloomer JR, Hu WS, Cerra FB. Gel-entrapment bioartificial liver therapy in galactosamine hepatitis. J Surg Res 1995; 59:179-84. [PMID: 7630125 DOI: 10.1006/jsre.1995.1151] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A need exists for an effective, safe bioartificial liver to support patients in fulminant hepatic failure (FHF). The purpose of this study was to determine the treatment efficacy of the novel gel-entrapment porcine hepatocyte bioartificial liver (BAL) in a fatal model of canine hepatic failure. FHF was produced in 27- to 30-kg halothane-anesthetized dogs by bolus infusion of the hepatotoxin D-galactosamine (D-Gal). Three groups were studied during the 48-hr experiment: Group D-Gal (n = 5) received galactosamine, 1.0 g/kg, iv at Time O, Group HepBAL (n = 5) received D-Gal followed by continuous hemoperfusion with the BAL device loaded with approximately 6 billion viable pig hepatocytes starting at Time 24 hr, and three dogs served as healthy controls (Group Control) and received no galactosamine. The primary endpoints were survival and coma development. Group D-Gal demonstrated 100% mortality from liver failure by 42 hr, characterized by a progressive rise in liver enzymes, total bilirubin, ammonia, and lactate and associated with coagulopathy, hypoglycemia, coma, and brain death. BAL therapy significantly delayed the onset of coma and improved survival (median 47 hr vs D-Gal median 36 hr). A significant delay in the rise of lactate and ammonia was also noted. BAL therapy prolonged survival and improved both laboratory and clinical markers of fatal liver failure. These data indicate that this BAL may have clinical utility in supporting human liver failure.
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Affiliation(s)
- T D Sielaff
- Department of Surgery, University of Minnesota, Minneapolis, USA
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35
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Abstract
A reproducible large animal model of fulminant hepatic failure was developed in the anesthetized dog by the administration of the amino sugar D-galactosamine. Galactosamine in 5% dextrose in water (D5W), was given as an intravenous bolus to 10 young male dogs weighing 27 to 30 kg. Three dogs that received an equal volume of D5W alone served as controls. Galactosamine at 0.5 g/kg (n = 5) produced significant biochemical evidence of liver injury with 100% survival at 48 hours. Galactosamine 1.0 g/kg (n = 5) yielded in 100% 48-hour mortality resulting from fulminant liver failure characterized by a progressive increase in liver enzymes, total bilirubin, ammonia, and lactate and associated coagulopathy, hypoglycemia, coma, and increased intracranial pressure. Necropsy showed liver pallor, ascites, and brain swelling. Liver histology showed significant hepatocellular necrosis. This clinically relevant large animal model will enable the quantitative evaluation of new technologies, such as the bioartificial liver, for the support of hepatic failure in humans.
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Affiliation(s)
- T D Sielaff
- Department of Surgery, University of Minnesota, Minneapolis
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36
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Lacerda MA, Bowers LD, Snover DC, Payne WD, Bloomer JR. Hepatic levels of cyclosporine and metabolites in patients after liver transplantation. Clin Transplant 1995; 9:35-8. [PMID: 7742581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Despite the critical role of the liver in the metabolism of cyclosporine, only a few studies have measured hepatic levels (CSAH) in patients receiving the drug, and none has directly assayed hepatic levels of the metabolites. In this study we measured CSAH and its principal metabolites (mono-OH and di-OH CSA) by HPLC/mass spectroscopy in 19 liver biopsy specimens collected from 14 patients who had undergone liver transplantation, in order to determine how they correlated with blood levels (CSAB). The hepatic concentrations were also compared with biochemical and histological parameters of cholestasis. A positive correlation was observed between CSAH and CSAB (r = 0.47), irrespective of the length of time the patients had received the drug (7 to 1662 days) as defined by the relationship: CSAH(ng/g wet weight) = 6.7 x CSAB(ng/ml)+338. Hepatic levels of metabolites exceeded those of the parent compound in 11 biopsy specimens. No correlation was found for CSAH and the metabolites and serum bilirubin or the degree of cholestasis in the liver biopsy specimens. These findings indicate that: (1) CSA is concentrated in liver tissue several-fold over blood; (2) The hepatic concentration can be estimated from the blood concentration even in the presence of cholestasis; (3) Significant levels of CSA metabolites are found in liver tissue, frequently exceeding the concentration of the parent compound.
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Affiliation(s)
- M A Lacerda
- Department of Medicine, University of Minnesota, Minneapolis, USA
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37
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Abstract
Fulminant hepatic failure has an exceedingly high mortality. Liver transplantation is the treatment option of choice. Unfortunately, one-third of patients with fulminant hepatic failure die awaiting a donor liver. For over 35 years attempts to remove or dilute putative toxins in the blood have been unsuccessful in improving survival rates. The use of biocompatible interfaces with blood or plasma and current hepatocyte culture techniques have led to the development of new support systems. This generation of bioartificial livers will hopefully provide the necessary hepatic functions and prevent many of the complications associated with fulminant hepatic failure. This paper will review the support systems tried and currently under investigation, with an emphasis on bioartificial livers.
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Affiliation(s)
- B M McGuire
- Department of Medicine, University of Minnesota Hospital and Clinic, Minneapolis, USA
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38
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Key NS, Rank JM, Freese D, Bloomer JR, Hammerschmidt DE. Hemolytic anemia in protoporphyria: possible precipitating role of liver failure and photic stress. Am J Hematol 1992; 39:202-7. [PMID: 1546716 DOI: 10.1002/ajh.2830390309] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Hemolytic anemia is not a common clinical feature in protoporphyria. In this report, we describe two patients in whom we have encountered severe hemolytic anemia. Both individuals had advanced hepatic disease as a complication of their porphyria and were undergoing orthoptic liver transplantation. The onset of hemolysis appeared to be related to the development of liver disease, and in both cases, the operative procedure acutely exacerbated the red cell destructive process. We suggest that liver involvement in protoporphyria may unmask hemolytic anemia, and that red cells in these individuals are hypersensitive to photooxidative stress, such as might occur during a prolonged operative procedure.
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Affiliation(s)
- N S Key
- Department of Medicine, University of Minnesota Medical School, Minneapolis
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39
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Straka JG, Bloomer JR, Kempner ES. The functional size of ferrochelatase determined in situ by radiation inactivation. J Biol Chem 1991; 266:24637-41. [PMID: 1761561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Ferrochelatase (EC 4.99.1.1) catalyzes the final step of heme biosynthesis, the insertion of iron(II) into protoporphyrin. It is an integral protein of the inner mitochondrial membrane. The functional size of bovine hepatic ferrochelatase has been studied in situ using radiation inactivation analysis. The functional unit required for enzymic activity in intact mitochondria was found to have a mass of 82 +/- 13 kDa. In contrast, the structural unit (evaluated in immunoblots following sodium dodecyl sulfate-polyacrylamide gel electrophoresis) has a mass of 40 +/- 10 kDa. Similar results were obtained when irradiation was performed on sodium cholate-solubilized mitochondria. The presence or absence of dithiothreitol during irradiation had no effect on target sizes obtained from either intact or solubilized mitochondria. Pairwise comparison of the functional and structural target sizes from each set of irradiated samples yielded a ratio of 2.0 +/- 0.4. Previous studies using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography have shown that a Mr 40,000 peptide is associated with ferrochelatase activity. This study shows that the functional size of bovine ferrochelatase is approximately 80 kDa; the data are most consistent with a model for active ferrochelatase composed of two structural subunits of about 40 kDa each.
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Affiliation(s)
- J G Straka
- Department of Medicine, University of Minnesota Medical School, Minneapolis 55455
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40
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Abstract
Liver transplantation is now accepted as the treatment of choice for tyrosinemia type I (hereditary tyrosinemia). In an effort to determine whether any factors in these patients would aid in predicting optimal timing of the transplant procedure, we evaluated several clinical, biochemical, and radiographic parameters in five successive patients undergoing liver transplant for tyrosinemia type I at the University of Minnesota. All five patients evidenced prolonged periods of clinical and metabolic stability with dietary therapy and four of five remained stable at the time of evaluation for transplantation. Nevertheless, all five suffered significant and unexpected complications of tyrosinemia prior to the time of liver transplant. Four developed renal stones, two were in liver failure, and one developed a neurologic crisis that left him completely paralyzed. Hepatocellular carcinoma was found in one of the five at transplant. We could identify no clinical, biochemical, or radiographic study that was predictive of the likelihood of significant complications of the disorder. Survival from the transplant procedure itself was 100%. The inability to predict or prevent significant complications of tyrosinemia and the favorable outcome from transplantation lead us to recommend liver transplant for all patients with tyrosinemia type I by 12 months of age.
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Affiliation(s)
- D K Freese
- Department of Pediatrics, University of Minnesota, Minneapolis 55455
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41
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Abstract
BACKGROUND Variegate porphyria is a genetic disorder of porphyrin metabolism in which patients may have both neurologic dysfunction and photocutaneous lesions. Biochemical confirmation of the diagnosis can be difficult, particularly in patients without neurologic dysfunction at the time of testing. The demonstration of increased fecal excretion of porphyrin is frequently used for this purpose, but levels may be normal. Since elevated fecal porphyrin levels in variegate porphyria are presumably a consequence of increased biliary excretion, we evaluated whether analysis of porphyrins in bile distinguishes better between patients with variegate porphyria and controls. METHODS Bile samples were collected by duodenal aspiration from 10 patients with proved variegate porphyria who had no neurologic symptoms when they were studied and 17 control subjects. Bile and fecal porphyrin levels were measured fluorometrically. RESULTS The mean total porphyrin concentration in bile in the patients with variegate porphyria was significantly higher than that in the controls (67.8 vs. 0.71 mumol per liter; P less than 0.00002). There was more than a ninefold difference between the highest level in any control subject and the lowest level in any patient with variegate porphyria. The mean fecal porphyrin level in the patients with variegate porphyria also differed significantly from that in the controls (0.79 vs. 0.14 mumol per gram of dry weight; P less than 0.007), but four patients had levels within the control range. CONCLUSIONS The concentration of porphyrin in bile is higher in patients with variegate porphyria than in controls, and the difference is greater than that for fecal porphyrin. Bile porphyrin measurements may be helpful in the evaluation of asymptomatic patients suspected of having variegate porphyria.
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Affiliation(s)
- G M Logan
- Department of Medicine, University of Minnesota, Minneapolis
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42
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Affiliation(s)
- J M Rank
- Department of Medicine, University of Minnesota Hospital and Clinic, Minneapolis 55455
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43
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Affiliation(s)
- J M Rank
- Department of Medicine, University of Minnesota, Minneapolis 55455
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44
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Affiliation(s)
- J M Rank
- University of Minnesota, Department of Medicine, Minneapolis 55455
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45
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Bloomer JR, Straka JG, Hill H, Weimer MK, Ruth GR. Comparison of bile porphyrin concentrations in cattle and human beings with protoporphyria. Am J Vet Res 1990; 51:1144-6. [PMID: 2389893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Blood and bile porphyrin concentrations were measured in cattle with protoporphyria and compared with those in human beings with the disease. Whereas the mean RBC porphyrin concentration in cattle was 18-fold greater than in human beings, the mean bile porphyrin concentration was only 78% greater. Sequential measurements over a 30-hour period in 1 animal with a bile fistula indicated that the ratio of total porphyrin to total bile acid in bile varied minimally. When the animal was given an IV infusion of taurocholate, the biliary excretion rate of porphyrin increased in parallel with that of bile acid, because of enhancement of bile flow. Thus, in cattle with protophorphyria, the concentration of porphyrin in bile is low compared with that of porphyrin in RBC, in contrast with findings in human beings, and adequate amounts of bile acids are secreted to maintain efficient protoporphyrin excretion. This explains, in part, why hepatobiliary disease has not been observed in cattle with protoporphyria, but has been seen in human beings with the disease.
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Affiliation(s)
- J R Bloomer
- Department of Medicine, University of Minnesota, Minneapolis 55455
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46
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Abstract
Porphyrins, their reduced congeners (porphyrinogens), and their precursors are accumulated and excreted in excessive amounts in the porphyrias because of defects in the enzymes of heme biosynthesis. The nature of these defects is being defined using biochemical and molecular biological techniques. The principal clinical manifestations in the porphyrias, photocutaneous lesions and neurological dysfunction, are linked to the biochemical abnormalities, and appropriate therapeutic interventions have accordingly been developed. The exogenous administration of metalloporphyrins and porphyrin derivatives, unlike the harmful effects of porphyrins in the porphyrias, may be of use in some clinical conditions, such as the treatment of hyperbilirubinemic states and the detection and therapy of certain cancers.
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Affiliation(s)
- J G Straka
- Department of Medicine, University of Minnesota, Minneapolis 55455
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47
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Abstract
A 38-yr-old woman with liver disease due to protoporphyria underwent orthotopic liver transplantation. The resected liver was cirrhotic and contained a massive amount of protoporphyrin, with numerous birefringent pigment deposits. Transplantation was accomplished without difficulty following blood volume exchange to reduce the blood protoporphyrin level. Sequential biopsy specimens obtained through the 13th month after transplantation showed no accumulation of protoporphyrin pigment deposits in the new liver. Portal inflammation observed in the liver biopsy specimen at 6 mo after transplantation resolved spontaneously. Erythrocyte and serum protoporphyrin levels returned to values similar to those in the pretransplantation period when the patient had normal hepatic function; the fecal level was lower. Thus orthotopic liver transplantation can be successfully done in patients with protoporphyria who have severe liver disease. Prolonged follow-up is needed to determine the ultimate outcome, however, as the new liver remains susceptible to protoporphyrin-induced damage.
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Affiliation(s)
- J R Bloomer
- Department of Medicine, University of Minnesota, Minneapolis
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48
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Kools AM, Straka JG, Hill HD, Whitmer DI, Holman RT, Bloomer JR. Modulation of hepatic ferrochelatase activity by dietary manipulation of mitochondrial phospholipid fatty acyl groups. Hepatology 1989; 9:557-61. [PMID: 2925161 DOI: 10.1002/hep.1840090409] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Ferrochelatase is an enzyme bound to the inner mitochondrial membrane, which is important in heme biosynthesis. Activity of purified ferrochelatase is affected by the presence of certain fatty acids. In the present study, we examined whether the activity of ferrochelatase is altered by dietary manipulation of the composition of mitochondrial membrane phospholipid fatty acyl groups. Rats were fed diets containing triolein, safflower or menhaden oil as 5% (w/w) of the diet. After 3 weeks, the animals were killed and liver mitochondria were isolated. Phospholipid fatty acid composition and ferrochelatase activity were assayed in the isolated mitochondria. Marked differences were seen. The proportion of oleic acid was highest in the triolein oil-fed group, that of linoleic and arachidonic acid was highest in the safflower oil-fed group and the proportion of eicosapentaenoic acid was highest in the menhaden oil-fed group. Ferrochelatase activity was greatest in the triolein oil-fed group and lowest in the menhaden oil-fed group regardless of whether the mitochondria were intact, sonicated or sonicated and treated with Tween 20. Mixing of mitochondria from menhaden oil-fed rats with triolein oil resulted in a significant increase in ferrochelatase activity. Membrane fluidity and activities of the mitochondrial membrane enzymes succinic dehydrogenase and cytochrome oxidase did not differ among the groups. We conclude that dietary manipulation of mitochondrial membrane phospholipid fatty acyl group composition can directly modulate hepatic ferrochelatase activity. This has potential application in the treatment of protoporphyria, the genetic disorder in which ferrochelatase activity is deficient.
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Affiliation(s)
- A M Kools
- Liver Center, University of Minnesota, Minneapolis 55455
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49
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Abstract
The porphyrias are metabolic disorders in which there are excessive accumulation and excretion of porphyrins and porphyrin precursors. Each of the porphyrias has a specific enzyme defect in the pathway of heme biosynthesis that explains the pattern of biochemical abnormalities that occur. However, some patients have the enzyme defect but do not have clinical or biochemical manifestations, indicating that other factors (e.g., demand for increased heme biosynthesis) are also important in causing disease expression. The major clinical manifestations are neurologic dysfunction and photosensitivity. The precise cause of the neurologic dysfunction has not been defined, but the likely possibilities are overproduction of delta-aminolevulinic acid, which may act as a neurotoxin, or a deficiency of heme (or both). The cutaneous lesions in the porphyrias are due to the photo-sensitizing and other effects of porphyrins that are deposited in the skin or are circulating in dermal blood vessels. Therapy is directed to modify the biochemical abnormalities. Most importantly, intravenous administration of hematin is used in the treatment of acute attacks of neurologic dysfunction. Prevention remains a cornerstone in management of patients with porphyria, and those with gene defects should be counseled regarding factors that precipitate acute attacks.
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Affiliation(s)
- J R Bloomer
- Division of Gastroenterology and Hepatology, University of Minnesota, Minneapolis
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50
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Abstract
The livers of patients who have protoporphyria and hepatic failure contain large amounts of pigment crystals. Two such patients underwent liver transplantation, providing the opportunity to identify the pigment crystals. Portions of liver were digested enzymically, sedimented through a sucrose gradient, treated with 1% sodium dodecylsulfate, and centrifuged to purify the crystals. Spectrophotometric and high-performance liquid chromatography analysis demonstrated them to be composed of protoporphyrin. Bile samples were obtained from the 2 patients, 4 other patients who did not have liver disease, and 10 control subjects. The porphyrin concentrations in bile from the 6 patients were significantly increased above controls (range 254-7884 micrograms/dl compared with 11-109 micrograms/dl). The ratio of protoporphyrin to bile acid in bile distinguished the 2 patients with advanced liver disease (3105 and 2756 micrograms/mmol) from the 4 patients without liver disease (range 61-926 micrograms/mmol). Thus, analysis of bile from patients with protoporphyria may help in evaluating their hepatobiliary status.
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Affiliation(s)
- K O Morton
- Department of Medicine, University of Minnesota, Minneapolis
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