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The porphyrias are clinically variable and genetically heterogeneous, predominantly hereditary metabolic diseases, which are caused by a dysfunction of specific enzymes in heme biosynthesis. Here, we provide an overview of the etiopathogenesis, clinic, differential diagnosis, laboratory diagnostics and therapy of these complex metabolic disorders and cover in detail the most common form of porphyria worldwide (porphyria cutanea tarda), the most frequent childhood porphyria (erythropoietic protoporphyria), and the most common neurocutaneous porphyria (variegate porphyria)., (© 2022 The Authors. Journal der Deutschen Dermatologischen Gesellschaft published by John Wiley & Sons Ltd on behalf of Deutsche Dermatologische Gesellschaft.)

The inborn errors of heme biosynthesis, the Porphyrias, include eight major disorders resulting from loss-of-function (LOF) or gain-of-function (GOF) mutations in eight of the nine heme biosynthetic genes. The major sites of heme biosynthesis are the liver and erythron, and the underlying pathophysiology of each of these disorders depends on the unique biochemistry, cell biology, and genetic mechanisms in these tissues. The porphyrias are classified into three major categories: 1) the acute hepatic porphyrias (AHPs), including Acute Intermittent Porphyria (AIP), Hereditary Coproporphyria (HCP), Variegate Porphyria (VP), and 5-Aminolevlulinic Acid Dehydratase Deficient Porphyria (ADP); 2) a hepatic cutaneous porphyria, Porphyria Cutanea Tarda (PCT); and 3) the cutaneous erythropoietic porphyrias, Congenital Erythropoietic Porphyria (CEP), Erythropoietic Protoporphyria (EPP), and X-Linked Protoporphyria (XLP). Their modes of inheritance include autosomal dominant with markedly decreased penetrance (AIP, VP, and HCP), autosomal recessive (ADP, CEP, and EPP), or X-linked (XLP), as well as an acquired sporadic form (PCT). There are severe homozygous dominant forms of the three AHPs. For each porphyria, its phenotype, inheritance pattern, unique genetic principles, and molecular genetic heterogeneity are presented. To date, >1000 mutations in the heme biosynthetic genes causing their respective porphyrias have been reported, including low expression alleles and genotype/phenotype correlations that predict severity for certain porphyrias. The tissue-specific regulation of heme biosynthesis and the unique genetic mechanisms for each porphyria are highlighted., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Porphyrias, is a general term for a group of metabolic diseases that are genetic in nature. In each specific porphyria the activity of specific enzymes in the heme biosynthetic pathway is defective and leads to accumulation of pathway intermediates. Phenotypically, each disease leads to either neurologic and/or photocutaneous symptoms based on the metabolic intermediate that accumulates. In each porphyria the distinct patterns of these substances in plasma, erythrocytes, urine and feces are the basis for diagnostically defining the metabolic defect underlying the clinical observations. Porphyrias may also be classified as either erythropoietic or hepatic, depending on the principal site of accumulation of pathway intermediates. The erythropoietic porphyrias are congenital erythropoietic porphyria (CEP), and erythropoietic protoporphyria (EPP). The acute hepatic porphyrias include ALA dehydratase deficiency porphyria, acute intermittent porphyria (AIP), hereditary coproporphyria (HCP) and variegate porphyria (VP). Porphyria cutanea tarda (PCT) is the only porphyria that has both genetic and/or environmental factors that lead to reduced activity of uroporphyrinogen decarboxylase in the liver. Each of the 8 enzymes in the heme biosynthetic pathway have been associated with a specific porphyria (Table 1). Mutations affecting the erythroid form of ALA synthase (ALAS2) are most commonly associated with X-linked sideroblastic anemia, however, gain-of-function mutations of ALAS2 have also been associated with a variant form of EPP. This overview does not describe the full clinical spectrum of the porphyrias, but is meant to be an overview of the biochemical steps that are required to make heme in both erythroid and non-erythroid cells., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The porphyrias are a group of metabolic disorders resulting from an innate abnormality in haem biosynthesis, and the clinical settings of which vary according to the genetic enzyme abnormality in question. These are genetic disorders with autosomal dominant or recessive inheritance of varying penetrance, and whose clinical expression differs according to the preferential location of haem precursors. Different classifications have been proposed according to genetic inheritance, the enzyme anomaly at issue, and clinical expression. The clinical classification distinguishes between acute porphyria (acute intermittent porphyria, porphyria variegata, hereditary coproporphyria), bullous cutaneous porphyrias (porphyria cutanea tarda, porphyria variegata and hereditary coproporphyria), painful photosensitive acute cutaneous porphyrias (erythropoietic protoporphyria and X-linked dominant protoporphyria), and rare recessive porphyrias (congenital erythropoietic porphyria, Doss porphyria, hepatoerythropoietic porphyria and harderoporphyria). Treatment depends on the clinical expression of the disorder., (Copyright © 2018. Published by Elsevier Masson SAS.)

Porphyrias are disorders caused by defects in the biosynthetic pathway of heme. Their manifestations can be divided into three distinct syndromes, each attributable to the accumulation of three distinct classes of molecules. The acute neurovisceral syndrome is caused by the accumulation of the neurotoxic porphyrin precursors, delta aminolevulinic acid, and porphobilinogen; the syndrome of immediate painful photosensitivity is caused by the lipid-soluble protoporphyrin IX and, the syndrome of delayed blistering photosensitivity, caused by the water-soluble porphyrins, uroporphyrin, and coproporphyrin. Porphyrias can manifest with one, or with a combination, of these syndromes, depending on whether one or more types of molecules are being accumulated. Iron plays a significant role in some of these conditions, as evidenced by improvements in both clinical manifestations and laboratory parameters, following iron depletion in porphyria cutanea tarda, or iron administration in some cases of X-linked erythropoietic protoporphyria. While the pathophysiology of a specific type of porphyrias, the protoporphyrias, appears to favor the administration of zinc, results so far have been conflicting, necessitating further studies in order to assess its potential benefit. The pathways involved in each disease, as well as insights into their pathobiological processes are presented, with an emphasis on the development of photosensitivity reactions.

The porphyrias are disorders of haem biosynthesis which present with acute neurovisceral attacks or disorders of sun-exposed skin. Acute attacks occur mainly in adults and comprise severe abdominal pain, nausea, vomiting, autonomic disturbance, central nervous system involvement and peripheral motor neuropathy. Cutaneous porphyrias can be acute or chronic presenting at various ages. Timely diagnosis depends on clinical suspicion leading to referral of appropriate samples for screening by reliable biochemical methods. All samples should be protected from light. Investigation for an acute attack: • Porphobilinogen (PBG) quantitation in a random urine sample collected during symptoms. Urine concentration must be assessed by measuring creatinine, and a repeat requested if urine creatinine <2 mmol/L. • Urgent porphobilinogen testing should be available within 24 h of sample receipt at the local laboratory. Urine porphyrin excretion (TUP) should subsequently be measured on this urine. • Urine porphobilinogen should be measured using a validated quantitative ion-exchange resin-based method or LC-MS. • Increased urine porphobilinogen excretion requires confirmatory testing and clinical advice from the National Acute Porphyria Service. • Identification of individual acute porphyrias requires analysis of urine, plasma and faecal porphyrins. Investigation for cutaneous porphyria: • An EDTA blood sample for plasma porphyrin fluorescence emission spectroscopy and random urine sample for TUP. • Whole blood for porphyrin analysis is essential to identify protoporphyria. • Faeces need only be collected, if first-line tests are positive or if clinical symptoms persist. Investigation for latent porphyria or family history: • Contact a specialist porphyria laboratory for advice. Clinical, family details are usually required.

The hereditary porphyrias comprise a group of eight metabolic disorders of the heme biosynthesis pathway. Each porphyria is caused by abnormal function at a separate enzymatic step resulting in a specific accumulation of heme precursors. Porphyrias are classified as hepatic or erythropoietic, based on the organ system in which heme precursors (δ-aminolevulinic acid [ALA], porphobilinogen and porphyrins) are overproduced. Clinically, porphyrias are characterized by acute neurovisceral symptoms, skin lesions or both. However, most if not all the porphyrias impair hepatic or gastrointestinal function. Acute hepatic porphyrias present with severe abdominal pain, nausea, constipation, confusion and seizure, which may be life threatening, and patients are at risk of hepatocellular carcinoma without cirrhosis. Porphyria Cutanea presents with skin fragility and blisters, and patients are at risk of hepatocellular carcinoma with liver iron overload. Erythropoietic protoporphyria and X-linked protoporphyria present with acute painful photosensitivity, and patients are at risk of acute liver failure. Altogether, porphyrias are still underdiagnosed, but once they are suspected, early diagnosis based on measurement of biochemical metabolites that accumulate in the blood, urine, or feces is essential so specific treatment can be started as soon as possible and long-term liver complications are prevented. Screening families to identify presymptomatic carriers is also crucial to prevent overt disease and chronic hepatic complications., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Porphyrias are inherited metabolic disorders that involve alterations in enzymes utilized in the heme biosynthetic pathway. Most of these conditions are inherited; however, some are believed to be acquired through environmental exposures. Patients with porhyrias often present with a wide range of clinical symptoms, making it difficult to diagnose. Treatments vary depending on clinical presentation. A thorough and detailed history is essential and key to discovering a porphyria diagnosis.

The simultaneous dysfunction of two enzymes within the heme biosynthetic pathway in a single patient is rare. Not more than 15 cases have been reported. A woman with a transient episode of severe photosensitivity showed a biochemical porphyrin profile suggestive of hereditary coproporphyria (HCP), whereas some of her relatives had a profile that was suggestive of variegate porphyria (VP). HCP and VP result from a partial enzymatic deficiency of coproporphyrinogen oxidase (CPOX) and protoporphyrinogen oxidase (PPOX), respectively. DNA analysis in the index patient revealed mutations in both the CPOX and PPOX genes, designated as c.557-15C>G and c.1289dupT, respectively. The CPOX mutation leads to a cryptic splice site resulting in retention of 14 nucleotides from intron 1 in the mRNA transcript. Both mutations encode null alleles and were associated with nonsense-mediated mRNA decay. Given the digenic inheritance of these null mutations, coupled with the fact that both HCP and VP can manifest with life-threatening acute neurovisceral attacks, the unusual aspect of this case is a relatively mild clinical phenotype restricted to dermal photosensitivity.

The porphyrias are diseases characterised by accumulation of porphyrins and porphyrin precursors owing to enzymatic deficiencies of the haem synthetic pathway. In the acute hepatic porphyrias accumulation of porphyrin precursors, in particular delta-aminolaevulinic acid (ALA), cause dysfunction of the central, peripheral and autonomic nervous systems. This leads to the characteristic clinical findings of abdominal pain, neuropsychiatric symptoms and neuropathy. The exact pathogenic mechanism is not clear but evidence to date suggests both direct toxic effects of ALA and intracellular metabolic derangement contribute to the neurologic disorders. This review explores the mechanisms of neural dysfunction in the acute porphyrias and the resultant clinical features of an acute attack., (Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.)

Hereditary porphyrias are a group of eight metabolic disorders of the haem biosynthesis pathway that are characterised by acute neurovisceral symptoms, skin lesions, or both. Every porphyria is caused by abnormal function of a separate enzymatic step, resulting in a specific accumulation of haem precursors. Seven porphyrias are the result of a partial enzyme deficiency, and a gain of function mechanism has been characterised in a new porphyria. Acute porphyrias present with acute attacks, typically consisting of severe abdominal pain, nausea, constipation, confusion, and seizure, and can be life-threatening. Cutaneous porphyrias present with either acute painful photosensitivity or skin fragility and blisters. Rare recessive porphyrias usually manifest in early childhood with either severe cutaneous photosensitivity and chronic haemolysis or chronic neurological symptoms with or without photosensitivity. Porphyrias are still underdiagnosed, but when they are suspected, and dependent on clinical presentation, simple first-line tests can be used to establish the diagnosis in all symptomatic patients. Diagnosis is essential to enable specific treatments to be started as soon as possible. Screening of families to identify presymptomatic carriers is crucial to decrease risk of overt disease of acute porphyrias through counselling about avoidance of potential precipitants., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Unlabelled: We sought to establish a causal relationship between oxidative stress and porphyria in patients and carriers. We reported changes in urinary porphyrin concentrations related to 8-hydroxy-2'-deoxyguanosine., Methods: We measured urinary 8-hydroxy-2'-deoxyguanosine concentration in porphyria patients and carriers with multifactorial inheritance as a possible marker of attack. The porphyria types included 10 patients with porphyria cutanea tarda, 5 with variegate porphyria, 8 with hereditary coproporphyria, 7 with congenital erythropoietic porphyria, 5 with erythropoietic protoporphyria, 5 with acute intermittent porphyria, 7 erythropoietic protoporphyria carriers, and 7 acute intermittent porphyria carriers., Results: Urinary porphyrin concentrations in these patients were significantly higher than those in healthy subjects (p<0.001). Urinary 8-hydroxy-2'-deoxyguanosine concentrations were significantly high in dermatopathy porphyria types namely porphyria cutanea tarda (p<0.001), variegate porphyria (p<0.05), hereditary coproporphyria (p<0.05), congenital erythropoietic phyria (p<0.05), and erythropoietic protoporphyria (p<0.001)., Conclusion: These results reveal that urinary 8-hydroxy-2'-deoxyguanosine concentration in cutis porphyria types is a good predictor of attack and abatement.

Recent advances in the molecular understanding of the porphyrias now offer specific diagnosis and precise definition of the types of genetic mutations involved in the disease. Molecular diagnostic testing is powerful and very useful in kindred evaluation and genetic counselling when a disease-responsible mutation has been identified in the family. It is also the only way to properly screen asymptomatic gene carriers, facilitating correct treatment and appropriate genetic counselling of family members at risk. However, it should be noted that DNA-based testing is for the diagnosis of the gene carrier status, but not for the diagnosis of clinical syndrome or severity of the disease, e.g. an acute attack. For the diagnosis of clinically expressed porphyrias, a logical stepwise approach including the analysis of porphyrins and their precursors should not be underestimated, as it is still very useful, and is often the best from the cost-effective point of view.

The porphyrias are a heterogeneous group of predominantly hereditary metabolic diseases resulting from a dysfunction of heme biosynthesis. Most of the porphyrias can manifest with a broad range of cutaneous symptoms on the sun-exposed areas of the body, whereas other variants reveal life-threatening acute neurological attacks. Further, mixed types of porphyrias exist. Besides the skin, other organs can be affected, such as the liver and the central nervous system. Therefore, interdisciplinary supervision of these patients is mandatory. In this review we will first present the clinical picture and diagnosis of the porphyrias, including the specific biochemical laboratory tests and a diagnostic algorithm. Thereafter, the current therapeutic concepts will be briefly addressed. Finally, we introduce the European Porphyria Initiative (EPI), an association of various European porphyria centers that is aiming at gathering the broad experience of internationally renowned porphyria experts for the development of European consensus guidelines for diagnosis and treatment of these metabolic disorders.

The porphyrias comprise a clinically and genetically heterogeneous group of diseases mostly arising from a genetically determined dysfunction of specific enzymes along the pathway of heme biosynthesis. Based on the occurrence or absence of cutaneous symptoms and life-threatening acute neurological attacks, the different types of porphyrias can either be classified into cutaneous and non-cutaneous forms or acute and non-acute forms. Establishing an accurate diagnosis might be difficult for two reasons: i) the porphyrias can manifest with a broad but unspecific spectrum of clinical symptoms mimicking several other disorders, and ii) biochemical examination of urine, feces, and blood can reveal overlapping findings. Fortunately, however, the advances in the fields of molecular genetics during recent years have provided us with the possibility of overcoming these diagnostic pitfalls. Therefore, in controversial cases the correct diagnosis can finally be made using molecular biological techniques. Due to the various facets of the porphyrias, diagnosis and treatment should always imply a close interdisciplinary collaboration to counsel and help patients and their families most efficiently.

The porphyrias are a group of disorders involving enzymatic defects in heme synthesis. The porphyrias classically manifest neuro-visceral or photocutaneous symptoms based on which enzyme in the heme metabolic pathway is deficient. Although rare, the porphyrias would most likely be encountered in the emergency department in patients presenting with chronic unspecified abdominal or musculoskeletal pain and those with new onset of psychiatric complaints.

The acute or inducible hepatic porphyrias comprise four inherited disorders of heme biosynthesis. They usually remain asymptomatic for most of the lifespan of individuals who inherit the specific enzyme deficiencies but may cause life-threatening attacks of neurovisceral symptoms. Failure to consider the diagnosis frequently delays effective treatment, and inappropriate diagnostic tests and/or mistaken interpretation of results may lead to misdiagnosis and inappropriate treatment. The four disorders are ALA dehydratase deficiency porphyria, acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria. Other conditions that clinically and biochemically may mimic acute porphyria include lead poisoning and hereditary tyrosinemia type I. The diagnosis of one of these acute porphyric syndromes should be considered in many patients with otherwise unexplained abdominal pain, severe constipation, systemic arterial hypertension, or other characteristic symptoms. Critical to the rapid diagnosis of the three most common of these disorders is demonstration of markedly increased urinary porphobilinogen (PBG) in a single-void urine specimen. The treatment of choice for all but mild attacks of the acute porphyrias is intravenous hemin therapy, which should be started as soon as possible. Intravenous glucose alone is recommended only for mild attacks (no weakness or hyponatremia) or until hemin is available.

The gene coding for the small ribosomal subunit RNA of Ploeotia costata contains an actively splicing group I intron (Pco.S516) which is unique among euglenozoans. Secondary structure predictions indicate that paired segments P1-P10 as well as several conserved elements typical of group I introns and of subclass IC1 in particular are present. Phylogenetic analyses of SSU rDNA sequences demonstrate a well-supported placement of Ploeotia costata within the Euglenozoa; whereas, analyses of intron data sets uncover a close phylogenetic relation of Pco.S516 to S-516 introns from Acanthamoeba, Aureoumbra lagunensis (Stramenopila) and red algae of the order Bangiales. Discrepancies between SSU rDNA and intron phylogenies suggest horizontal spread of the group I intron. Monophyly of IC1 516 introns from Ploeotia costata, A. lagunensis and rhodophytes is supported by a unique secondary structure element: helix P5b possesses an insertion of 19 nt length with a highly conserved tetraloop which is supposed to take part in tertiary interactions. Neither functional nor degenerated ORFs coding for homing endonucleases can be identified in Pco.S516. Nevertheless, degenerated ORFs with His-Cys box motifs in closely related intron sequences indicate that homing may have occurred during evolution of the investigated intron group.

From time to time a patient may attend your practice with a systemic condition that you may or may not remember from the small print of your undergraduate text books. This paper describes one such systemic condition, porphyria, and its dental management. This paper also describes the use of relative analgesia as an aid to anxiety management in porphyria.

As usually occurs for rare diseases, the word "PORPHYRIA" often recalls a confused topic with shaded boundaries, presenting "bullous" skin lesions, rare opportunity of diagnosis in clinical practice, unknown pathogenesis, and almost absent therapeutic options. The goal of this review is to draw attention to this topic, as new diagnostic and therapeutic tools might change the natural history of this disease. Porphyrias are disorders resulting from abnormalities of porphyrin metabolism. Porphyrins are molecules made up of four pyrrol rings, which constitute haeme-proteins, including haemoglobin. Following the "trigger" enzyme delta-aminolevulinic acid (ALA) synthase, which is capable of condensing succynil CoA and glycine, seven additional enzymes are involved in the process that eventually leads to haeme biosynthesis. Porphyrias are the result of total or partial deficiencies in these seven enzymes involved in haeme synthesis. Usually, the final haeme product exerts a negative feed-back on its synthesis. The enzyme deficiency that occurs in porphyrias is responsible for reduced haeme production, which, in turn, allows the cascade to be stimulated by increased activity of the trigger enzyme, ALA-synthase (ALA-s). However, due to the subsequent enzyme defects, notwithstanding increased ALA-s activity, haeme synthesis is blunted and intermediate metabolites accumulate. Clinical manifestations depend on which step the enzymatic defect occurs: if enzymatic defects are in the initial steps of the metabolic cascade, early metabolic intermediates will accumulate [i.e. ALA and porphobilinogen (PBG)] responsible for attacks of neurological dysfunction; if the enzymatic defects are in the final steps, sunlight-induced cutaneous lesions (phtotosensitivity) due to porphyrin accumulation in the skin will develop. The seven major human porphyrias may be classified into "hepatic or erythropoietic porphyrias" depending on the organ/tissue where metabolic alterations are more evident, or "acute or chronic porphyrias" depending on the prevalence of clinical symptoms, if neurologic (acute) or cutaneous (chronic). Only a small number of people with inherited enzyme deficiency will develop overt clinical disease, mainly because of the role of acquired aggravating and precipitating factors, such as drugs, hormonal causes, infection, caloric restriction, alcohol. The biochemical diagnosis of porphyrias relies on the detection of the consequences of increased ALA-s activity in the liver: overproduction, accumulation and increased excretion of early (ALA, PBG) or late (porphyrins) intermediate compounds in plasma, faeces and urine. A major difficulty arises from the knowledge that such abnormalities may be completely absent during the remission phases of the disease. Only in very specialised Centres it is now possible to measure specific haeme synthesis enzyme defects, and to perform molecular diagnosis by DNA analysis. The true prevalence of the diseases is unknown, ranging from 1:500 to 1:50,000. Therapeutic strategies include withdrawal of all common precipitants (drug, alcohol, fasting, infection), use of opiates and chlorpromazine, carbohydrates (300-400 g/day) and infusion of human haemine. Genetic therapies are being studied for the future.

Background: Pseudoporphyria is a diagnosis that is used when porphyria-like clinical lesions arise in the setting of normal porphyrin levels. This condition was first described in the 1960s and was initially related to the use of certain antibiotic drugs. In 1985, pseudoporphyria was first attributed to the use of nonsteroidal antiinflammatory drugs (NSAIDs). Subsequently, a host of NSAIDs and other drugs have been found to elicit the same clinical entity. The exact mechanism by which certain drugs create clinical lesions resembling porphyria cutanea tarda or erythropoietic protoporphyria is still unknown. A phototoxic mechanism is hypothesized., Objective: We describe six patients diagnosed with pseudoporphyria and detail the diagnostic tests leading to the eventual diagnosis., Results: The patients ranged in age from 27 to 59 years and had a female:male predominance of 2:1. The offending NSAID was DayPro (oxaprozin) for three of the patients, Relafen (nabumetone) for two of the patients, and Aleve (naproxen) for one patient. For each patient, histology and immunofluorescence was either consistent with the diagnosis of porphyria cutanea tarda or nonspecific, while serum, stool, and urine porphyrins did not support that diagnosis. Withdrawal of the offending agent provided relief from the clinical symptoms for each patient. None of our patients were rechallenged with the putative offending drug. However, prolonged avoidance has provided a sustained remission from symptoms in all six patients., Conclusions: Pseudoporphyria is a relatively rarely reported condition. Clinical suspicion with appropriate laboratory and histopathologic findings help to make this diagnosis, and exclude true porphyrias. Rechallenge with the offending drug to produce symptom relapse has been proposed to be helpful in confirming this diagnosis of exclusion. Since all 6 patients with drug-induced pseudoporphyria experienced resolution of their symptoms after discontinuing the offending agent, we propose that this clinical correlation alone is sufficient to confirm this diagnosis. Our observation of six new cases of NSAID-induced pseudoporphyria over a two-year interval suggests that this is not a rare entity.

The relationship between clinical features and specific alterations of heme metabolism allows the accurate diagnosis and classification of porphyrias. The acute porphyric attack is characterized by frequently confusing clinical pattern of abdominal-psiquic- and neurological symptoms. An increased urinary excretion of porphobilinogen, which can be quickly detected by the Hoesch test, confirms the diagnosis of this acute attack. Increased plasma porphyrin levels are associated with skin lesions, which are the characteristic features of the cutaneous porphyrias. Their presence is easily and rapidly detected by a fluorimetric scanning of PBS (phosphate buffer saline) diluted samples. Characterization of the molecular defects in genes coding for the enzymes involved in the heme synthetic pathway is complementary to the biochemical methods. Molecular analysis permits an accurate classification of those biochemically unclassified patients and allows prenatal diagnosis in those homozygotic cases where a severe prognosis is suspected.

Acute porphyrias are classified into 3 distinct groups of rare genetic disorders of metabolic enzyme biosynthesis. Acute porphyrias can significantly impact multiple organ systems, which often provides a challenge to the dentist presented with such a patient. A case of hereditary coproporphyria is reported in a patient with many of the classical signs and symptoms. The patient also had complex dental needs that required special medical and pharmacotherapeutic modifications. The acute porphyrias are reviewed by the authors with presentation of this challenging case. Recommendations for other dental health care professionals encountering these patients are then presented.

There have been discrepancies in reports of total cholesterol and low density lipoprotein (LDL)-cholesterol levels in patients with acute porphyria. Some studies have found that acute porphyria patients have increased levels while others do not. The aim of this study has been to evaluate the lipid profile in a series of patients with acute porphyria, in order to help clarify these differences. Serum lipoprotein levels were studied in 30 patients (25 women and five men; age:38+/-10 years) with asymptomatic acute porphyria. Controls were 30 healthy volunteers matched for age and gender. For 13 patients and 15 controls, lipoprotein lipase and hepatic lipase activities were determined. Patients exhibited increased levels of total-cholesterol, LDL-cholesterol, high density lipoprotein (HDL)-cholesterol and apolipoprotein (apo)-A1 compared with controls (P4 mmol/l in 15 patients (50%). Levels of total triglycerides, very low density lipoprotein (VLDL)-triglycerides, VLDL-cholesterol, apo-B and lipoprotein(a) were similar in patients and controls. The hepatic lipase activity tended to be lower in patients than controls (33.8+/-17.7 vs. 50.4+/-23.0 pkat/ml; P=0.05). In conclusion, in patients with asymptomatic acute porphyria an increase of total and LDL-cholesterol was found. The cardiovascular risk conferred by this factor may be attenuated by increased HDL-cholesterol and apo-A1.

Alcohol is a porphyrinogenic agent which may cause disturbances in porphyrin metabolism in healthy persons as well as biochemical and clinical manifestations of acute and chronic hepatic porphyrias. After excessive consumption of alcohol, a temporary, clinically asymptomatic secondary hepatic coproporphyrinuria is observable, which can become persistent in cases of alcohol-induced liver damage. Nowadays, the alcohol-liver-porphyrinuria syndrome is the first to be mentioned in secondary hepatic disturbances of porphyrin metabolism. Acute hepatic porphyrias (acute intermittent porphyria, variegate porphyria and hereditary coproporphyria) are considered to be molecular regulatory diseases, in contrast to non-acute, chronic hepatic porphyria, clinically appearing as porphyria cutanea tarda (PCT). Porphyrins do not accumulate in the liver in acute porphyrias, whereas in chronic hepatic porphyrias they do. Thus, chronic hepatic porphyria is a porphyrin-accumulation disease, whereas acute hepatic porphyrias are haem-pathway-dysregulation diseases, characterized in general by induction of delta-aminolevulinic acid synthase in the liver and excessive stimulation of the pathway without storage of porphyrins in the liver. The clinical expression of acute hepatic porphyrias can be triggered by alcohol, because alcohol augments the inducibility of delta-aminolevulinic acid synthase. In chronic hepatic porphyrias, however, which are already associated with liver damage, alcohol potentiates the disturbance of the decarboxylation of uro- and heptacarboxyporphyrinogen, which is followed by a hepatic accumulation of uro- and heptacarboxyporphyrin and their sometimes extreme urinary excretion. Especially in persons with a genetic deficiency of uroporphyrinogen decarboxylase, but also in patients with the so-called sporadic variety of PCT, alcohol is able to transform an asymptomatic coproporphyrinuria into PCT. Alcohol has many biochemical and clinical effects on porphyrin and haem synthesis both in humans and laboratory animals. Ethanol suppresses the activity of porphobilinogen synthase (synonym: delta-aminolevulinic acid dehydratase), uroporphyrinogen decarboxylase, coproporphyrinogen oxidase and ferrochelatase, whereas it induces the first and rate-limiting enzyme in the pathway, delta-aminolevulinic acid synthase and also porphobilinogen deaminase. Therefore, teetotalism is a therapeutically and prophylactically important measure in all types of hepatic porphyrias.

Objectives: To differentiate the porphyrias by clinical and biochemical methods., Design and Methods: We describe levels of blood, urine, and fecal porphyrins and their precursors in the porphyrias and present an algorithm for their biochemical differentiation. Diagnoses were established using clinical and biochemical data. Porphyrin analyses were performed by high performance liquid chromatography., Results and Conclusions: Plasma and urine porphyrin patterns were useful for diagnosis of porphyria cutanea tarda, but not the acute porphyrias. Erythropoietic protoporphyria was confirmed by erythrocyte protoporphyrin assay and erythrocyte fluorescence. Acute intermittent porphyria was diagnosed by increases in urine delta-aminolevulinic acid and porphobilinogen and confirmed by reduced erythrocyte porphobilinogen deaminase activity and normal or near-normal stool porphyrins. Variegate porphyria and hereditary coproporphyria were diagnosed by their characteristic stool porphyrin patterns. This appears to be the most convenient diagnostic approach until molecular abnormalities become more extensively defined and more widely available.

The porphyrias are inherited disorders of haem synthesis and must be considered in the differential diagnosis of numerous disorders.

Porphyrias arise due to enzyme defects in the haem synthetic pathway. They are of concern to the anaesthetist as acute crises may be precipitated by anaesthetic drugs. Anaesthesia must be carefully managed in patients with porphyria in order to achieve a successful outcome.

The porphyrias are defined by specific enzymes having diminished activity. More enzymes have become available for routine testing. Measurement of urine and stool porphyrin and porphyrin precursor elevations are important, but in many instances are not found or found in confusing patterns. The use of enzyme analysis can often be helpful in identifying those patients with a genetically diminished enzyme activity level. Looking back over the last four years, modifications in evaluating patients for porphyria were developed and are related in this article. In 91 patients, patterns of enzyme deficiencies were seen that have been observed by others; however, new observations have been made. While many of the enzymes in the porphyrin pathway are available for testing, others need to come on line as soon as possible, particularly protoporphyrinogen oxidase.

The porphyrias are diseases of enzyme deficiency in the heme synthetic pathway. They are classified into eight subtypes, two of which, ALADP and HEP, have been added as new subtypes during the past 10 years. These eight subtypes are divided into two groups, hepatic and erythropoietic. Hepatic porphyrias include AIP, ALADP, VP, HCP, PCT and HEP. Erythropoietic porphyrias consist of two subtypes, CP and EPP. From the clinical point of view, these subtypes may, also, be divided into acute and cutaneous porphyrias. AIP, ALADP, VP and HCP belong to acute porphyria. CP, EPP, PCT, and HEP to cutaneous porphyria. The diagnosis of porphyrias and differential diagnosis of subtypes are made by analyzing porphyrias and it's precursors in urine, blood and feces.

The porphyrias are a metabolic disorders of heme biosynthesis characterized by the excessive production and excretion of porphyrins and porphyrin precursors. They are caused by defects in specific enzyme activities and classified into 7 subtypes. Some of them present with photosensitivity of skin and intermittent acute attacks related to nervous system disturbance. Especially in acute intermittent porphyria, patients have recurrent acute attacks of abdominal, neurologic, and psychiatric symptoms. Some precipitating factors; including drugs, hormonal factors, starvation, and stress; induces acute attacks. In this article, pathophysiology of the neurologic symptoms and relation between precipitating factors, especially focused in drugs, and acute attacks may be reviewed.

Porphyrins are essential substances for the biosynthesis of heme. Porphyria results from a disorder in the metabolism of porphyrin. Patients suffering from Porphyria exhibit changes in their porphyrin profiles as measured in excretia and organs. A highly sensitive and simple analytical method using high-performance liquid chromatography (HPLC) for all porphyrin metabolites in urine was established. This method is able to separate porphyrins such as uroporphyrin, carboxylic acid porphyrins of hepta-, hexa-, penta-, and coproporphyrin isomers of I and III in a sample of human urine. In this study, the combination of HPLC with a computer system for automated porphyria diagnosis was investigated. The profile of all urinary porphyrins from patients with various Porphyria were measured by HPLC and diagnosed by the computer diagnostic system. This system enabled the estimation of 5 types of porphyrias with a high accuracy of diagnosis.

There are seven porphyrias which are caused by defective functions of the enzymes in the haem biosynthesis. The clinical classification of porphyrias are divided into three types which are neuroporphyria, neurocutaneous porphyria and cutaneous porphyria. For acute porphyric attack of neuroporphyria and neurocutaneous porphyria, the treatments of choice are administration of glucose and/or hematin, haem arginate and tinprotoporphyrin. Porphyria cutanea tarda in cutaneous porphyria is controlled by removal of iron by phrebotomies or low-dose chloriquine. A novel approach of intravenous administration of interferon may be useful to control the associated case of chronic hepatitis type C. Skin symptoms in erythropoietic protoporphyria can be alleviated with beta carotene. Hepatic failure due to protoporphyria may need a liver transplantation. Cimetidine, a H2-receptor antagonist, may be useful in the treatment of acute porphyric attack and in remission stage in neuroporphyrias, neurocutaneous porphyrias and cutaneous porphyrias such as porphyria cutanea tarda and protoporphyria.