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Porphyria, Acute Intermittent - Top 30 Publications


Comprehensive analysis of the tryptophan metabolome in urine of patients with acute intermittent porphyria.

Acute intermittent porphyria (AIP) is a rare metabolic disorder due to a deficiency of porphobilinogen deaminase, the third enzyme of the heme biosynthetic pathway. This low enzymatic activity may predispose to the appearance of acute neurological attacks. Seminal studies suggested that AIP was associated with changes in tryptophan homeostasis with inconclusive results. Therefore, the aim of this study was to analyze the urinary metabolome of AIP patients focusing on tryptophan metabolism using state-of-the-art technology.

Pure motor axonal neuropathy triggered by antituberculous therapy in an undiagnosed case of acute intermittent porphyria.

A man aged 22 years misdiagnosed as suffering from recurrent abdominal tuberculosis, in view of recurrent abdominal pain was treated for abdominal tuberculosis in the past. The patient was prescribed antituberculous therapy. 2 months after starting treatment, he developed progressive weakness of all 4 limbs. Electrodiagnostic examination revealed an acute severe motor axonal neuropathy. Further workup revealed elevated porphyrin precursors in urine.

Acute Intermittent Porphyria Presenting with Posterior Reversible Encephalopathy Syndrome, Accompanied by Prolonged Vasoconstriction.

A 20-year-old Japanese woman had an attack of acute intermittent porphyria (AIP). Magnetic resonance imaging (MRI) revealed symmetrical lesions in the cerebrum and cerebellar hemisphere, corresponding to posterior reversible encephalopathy syndrome (PRES). Our administration of heme arginate gradually improved the clinical condition associated with AIP and the level of metabolite of nitric oxide (NO), which is a vascular dilator. Repeated MRI and magnetic resonance angiography revealed exacerbated PRES, part of which showed a small infarction, accompanied by progressive vasoconstriction. These findings suggest that the recovery of NO by heme replacement alone is insufficient for preventing brain damage during an AIP attack.

Update review of the acute porphyrias.

Acute porphyrias are rare inherited disorders due to deficiencies of haem synthesis enzymes. To date, all UK cases have been one of the three autosomal dominant forms, although penetrance is low and most gene carriers remain asymptomatic. Clinical presentation is typically with acute neurovisceral attacks characterised by severe abdominal pain, vomiting, tachycardia and hypertension. Severe attacks may be complicated by hyponatraemia, peripheral neuropathy sometimes causing paralysis, seizures and psychiatric features. Attacks are triggered by prescribed drugs, alcohol, hormonal changes, fasting or stress. The diagnosis is made by finding increased porphobilinogen excretion in a light-protected random urine sample. Management includes administration of intravenous human haemin and supportive treatment with non-porphyrinogenic drugs. A few patients develop recurrent attacks, a chronic illness requiring specialist management. Late complications include chronic pain, hepatocellular carcinoma, chronic renal failure and hypertension. In the UK, the National Acute Porphyria Service provides clinical advice and supplies haemin when indicated.

Systemic inflammation in acute intermittent porphyria: a case-control study.

This study aimed to examine whether acute intermittent porphyria (AIP) is associated with systemic inflammation and whether the inflammation correlates with disease activity. A case-control study with 50 AIP cases and age-, sex- and place of residence-matched controls was performed. Plasma cytokines, insulin and C-peptide were analysed after an overnight fast using multiplex assay. Long pentraxin-3 (PTX3) and complement activation products (C3bc and TCC) were analysed using enzyme-linked immunosorbent assay (ELISA). Urine porphobilinogen ratio (U-PBG, µmol/mmol creatinine), haematological and biochemical tests were performed using routine methods. Questionnaires were used to register AIP symptoms, medication and other diseases. All 27 cytokines, chemokines and growth factors investigated were increased significantly in symptomatic AIP cases compared with controls (P < 0·0004). Hierarchical cluster analyses revealed a cluster with high visfatin levels and several highly expressed cytokines including interleukin (IL)-17, suggesting a T helper type 17 (Th17) inflammatory response in a group of AIP cases. C3bc (P = 0·002) and serum immunoglobulin (Ig)G levels (P = 0·03) were increased significantly in cases with AIP. The U-PBG ratio correlated positively with PTX3 (r = 0·38, P = 0·006), and with terminal complement complex (TCC) levels (r = 0·33, P = 0·02). PTX3 was a significant predictor of the biochemical disease activity marker U-PBG in AIP cases after adjustment for potential confounders in multiple linear regression analyses (P = 0·032). Prealbumin, C-peptide, insulin and kidney function were all decreased in the symptomatic AIP cases, but not in the asymptomatic cases. These results indicate that AIP is associated with systemic inflammation. Decreased C-peptide levels in symptomatic AIP cases indicate that reduced insulin release is associated with enhanced disease activity and reduced kidney function.

Molecular characterisation of acute intermittent porphyria in a cohort of South African patients and kinetic analysis of two expressed mutants.

Acute intermittent porphyria (AIP) is a disorder of the haem biosynthetic pathway caused by mutations in the hydroxymethylbilane synthase (HMBS) gene. Knowledge of the spectrum of mutations present in South Africa is limited. This study presents the molecular profile of 20 South African patients with AIP, and the kinetic analysis of one novel expressed mutated HMBS enzyme and a previously identified mutation at the same position.

Emerging therapies for acute intermittent porphyria.

Acute intermittent porphyria (AIP) is an autosomal dominant metabolic disease caused by hepatic deficiency of hydroxymethylbilane synthase (HMBS), the third enzyme of the heme synthesis pathway. The dominant clinical feature is acute neurovisceral attack associated with high production of potentially neurotoxic porphyrin precursors due to increased hepatic heme consumption. Current Standard of Care is based on a down-regulation of hepatic heme synthesis using heme therapy. Recurrent hyper-activation of the hepatic heme synthesis pathway affects about 5% of patients and can be associated with neurological and metabolic manifestations and long-term complications including chronic kidney disease and increased risk of hepatocellular carcinoma. Prophylactic heme infusion is an effective strategy in some of these patients, but it induces tolerance and its frequent application may be associated with thromboembolic disease and hepatic siderosis. Orthotopic liver transplantation is the only curative treatment in patients with recurrent acute attacks. Emerging therapies including replacement enzyme therapy or gene therapies (HMBS-gene transfer and ALAS1-gene expression inhibition) are being developed to improve quality of life, reduce the significant morbidity associated with current therapies and prevent late complications such as hepatocellular cancer or kidney failure in HMBS mutation carriers with long-standing high production of noxious heme precursors. Herein, we provide a critical digest of the recent literature on the topic and a summary of recently developed approaches to AIP treatment and their clinical implications.

Acute intermittent porphyria precipitated by atazanavir/ritonavir.

Porphyrias are a group of metabolic disorders that are relatively uncommon and underdiagnosed. Although the association between HIV infection and antiretrovirals with porphyria cutanea tarda is well established, there are fewer data linking HIV and the acute hepatic porphyrias. We report the first case of acute intermittent porphyria precipitated by the drugs atazanavir and ritonavir, presenting with unexplained abdominal pain.

Not Available.

The attack of acute porphyria Based on in silico evidence of pharmacokinetic, pharmacodynamic, and physiologic properties, have approximately 1 300 medicinal drugs been assessed with regard to the specific risk to carriers of acute porphyria. The classifications have been published in booklet form, together with prophylactic advice to the carriers and suggestions for doctors in charge of their care. The risk-classifications rest on the behavior of the drug in an extended molecular model of the attack of acute porphyria. In this, symptoms are effects of 5-aminolevulinate (ALA) produced in surplus after acceleration of enzyme-deficient heme biosynthesis, taking place during induction of drug-metabolizing cytochromes P450 and triggered by hepatocellular nuclear receptors, activated by the drug. The process is enhanced by glucagon- and sirtuin-dependent molecular processes activated in stress and cellular energy deficit, and enhanced and prolonged by auto-generating ALA.

A Comprehensive Rehabilitation Program and Follow-up Assessment for Acute Intermittent Porphyria.

Acute intermittent porphyria (AIP) is an infrequent metabolic disease that can cause severe disability or death without timely treatment. A porphyric attack occurs when genetic factors combine with trigger factors, and diagnosis may be delayed owing to nonspecific symptoms. Recovery from AIP can be nearly or fully complete with proper treatment, which includes intravenous hematin administration, the control of trigger factors, and a comprehensive rehabilitation program. The aim of this case report was to describe the clinical evolution of a 43-year-old woman with AIP and a polyneuropathy. The patient was treated through a comprehensive rehabilitation program, with outcomes evaluated by the Functional Independence Measure and the Berg scales during rehabilitation and postdischarge follow-up. After completing the comprehensive rehabilitation program, the patient achieved a satisfactory level of functional independence, allowing for social and work reintegration. We conclude that an early and multidisciplinary approach is essential for regaining optimal functionality after AIP.

Radiopharmaceuticals in Acute Porphyria.

The acute porphyrias are a group of rare metabolic disorders of the heme biosynthetic pathway. Carriers of the acute porphyria gene are prone to potentially fatal acute attacks, which can be precipitated by drug exposure. It is therefore important to know whether a drug is safe for carriers of the acute porphyria gene. In this study, radiopharmaceuticals were assessed on their porphyrogenicity (ie, the potential of a drug to induce an attack).

Acute intermittent porphyria-related leukoencephalopathy.

To identify the genetic etiology of a distinct leukoencephalopathy with autosomal recessive inheritance in a single family.

Acute Intermittent Porphyria: Predicted Pathogenicity of HMBS Variants Indicates Extremely Low Penetrance of the Autosomal Dominant Disease.

Acute intermittent porphyria results from hydroxymethylbilane synthase (HMBS) mutations that markedly decrease HMBS enzymatic activity. This dominant disease is diagnosed when heterozygotes have life-threatening acute attacks, while most heterozygotes remain asymptomatic and undiagnosed. Although >400 HMBS mutations have been reported, the prevalence of pathogenic HMBS mutations in genomic/exomic databases, and the actual disease penetrance are unknown. Thus, we interrogated genomic/exomic databases, identified non-synonymous variants (NSVs) and consensus splice-site variants (CSSVs) in various demographic/racial groups, and determined the NSV's pathogenicity by prediction algorithms and in vitro expression assays. Caucasians had the most: 58 NSVs and two CSSVs among ∼92,000 alleles, a 0.00575 combined allele frequency. In silico algorithms predicted 14 out of 58 NSVs as "likely-pathogenic." In vitro expression identified 10 out of 58 NSVs as likely-pathogenic (seven predicted in silico), which together with two CSSVs had a combined allele frequency of 0.00056. Notably, six presumably pathogenic mutations/NSVs in the Human Gene Mutation Database were benign. Compared with the recent prevalence estimate of symptomatic European heterozygotes (∼0.000005), the prevalence of likely-pathogenic HMBS mutations among Caucasians was >100 times more frequent. Thus, the estimated penetrance of acute attacks was ∼1% of heterozygotes with likely-pathogenic mutations, highlighting the importance of predisposing/protective genes and environmental modifiers that precipitate/prevent the attacks.

Acute intermittent porphyria: a missed diagnosis in pre-pubertal children with recurrent abdominal pain.

Posterior reversible encephalopathy syndrome revealing acute intermittent porphyria.

Acute intermittent porphyria leading to posterior reversible encephalopathy syndrome (PRES): a rare cause of abdominal pain and seizures.

Acute intermittent porphyria (AIP) is an inherited deficiency in the haem biosynthesis pathway. AIP is rare, affecting around 1 in 75 000 people. Acute attacks are characterised by abdominal pain associated with autonomic, neurological and psychiatric symptoms. AIP is rarely associated with posterior reversible encephalopathy syndrome (PRES). PRES is a clinicoradiological condition caused by the failure of the posterior circulation to autoregulate, resulting in cerebral oedema, headaches, nausea and seizures. This association is important because drugs used in the management of seizures may worsen an attack of AIP. This article describes a case of AIP and PRES in a young woman.

Femoral and sciatic nerve block for knee arthroscopy in a patient with acute intermittent porphyria.

Acute intermittent porphyria is an autosomal dominant disorder that results from a partial deficiency of porphobilinogen deaminase and that causes very severe symptoms. Attacks may be triggered by a series of drugs and by other factors that the anesthesiologist should be aware of in order to reduce morbidity and mortality. Our objective is to review anesthetic considerations in acute intermittent porphyria. We present the case of a patient diagnosed with acute intermittent porphyria who was scheduled for knee arthroscopy. The anesthetic technique used was a femoral and sciatic nerve block under sedation with an infusion of remifentanil. The surgery proceeded without incident and the patient was discharged home after 24h. We consider the use of a peripheral plexus block of the lower limb to have been the safest anesthetic technique for this patient.

Acute intermittent porphyria exacerbation following in vitro fertilization treatment.

Assisted reproductive technology is commonly used for women with infertility. We report a case of acute intermittent porphyria associated with in vitro fertilization treatment.

Anesthetic implication of tricuspid valve replacement in a patient with acute intermittent porphyria.

Facing a patient with acute intermittent porphyria (AIP), there is narrow safety margin which circumscribe all the therapeutic actions including choice of drugs. This would become even more complicated when it comes to a stressful and drug-dependent process like a cardiopulmonary bypass. According to author's researches, no specific AIP case of tricuspid valve (TV) replacement is reported recently. Furthermore, fast-track anesthesia was safely used in this 37-year-old male known the case of AIP, who was a candidate for TV replacement and removing the port catheter. The patient was extubated subsequently, only 3 h after entering the Intensive Care Unit.

Recombinant AAV Integration Is Not Associated With Hepatic Genotoxicity in Nonhuman Primates and Patients.

Recombinant adeno-associated viral vectors (rAAV) currently constitute a real therapeutic strategy for the sustained correction of diverse genetic conditions. Though a wealth of preclinical and clinical studies have been conducted with rAAV, the oncogenic potential of these vectors is still controversial, particularly when considering liver-directed gene therapy. Few preclinical studies and the recent discovery of incomplete wild-type AAV2 genomes integrated in human hepatocellular carcinoma biopsies have raised concerns on rAAV safety. In the present study, we have characterized the integration of both complete and partial rAAV2/5 genomes in nonhuman primate tissues and clinical liver biopsies from a trial aimed to treat acute intermittent porphyria. We applied a new multiplex linear amplification-mediated polymerase chain reaction (PCR) assay capable of detecting integration events that are originated throughout the rAAV genome. The integration rate was low both in nonhuman primates and patient's samples. Importantly, no integration clusters or events were found in genes previously reported to link rAAV integration with hepatocellular carcinoma development, thus showing the absence of genotoxicity of a systemically administered rAAV2/5 in a large animal model and in the clinical context.

Glucose metabolism during fasting is altered in experimental porphobilinogen deaminase deficiency.

Porphobilinogen deaminase (PBGD) haploinsufficiency (acute intermittent porphyria, AIP) is characterized by neurovisceral attacks when hepatic heme synthesis is activated by endogenous or environmental factors including fasting. While the molecular mechanisms underlying the nutritional regulation of hepatic heme synthesis have been described, glucose homeostasis during fasting is poorly understood in porphyria. Our study aimed to analyse glucose homeostasis and hepatic carbohydrate metabolism during fasting in PBGD-deficient mice. To determine the contribution of hepatic PBGD deficiency to carbohydrate metabolism, AIP mice injected with a PBGD-liver gene delivery vector were included. After a 14 h fasting period, serum and liver metabolomics analyses showed that wild-type mice stimulated hepatic glycogen degradation to maintain glucose homeostasis while AIP livers activated gluconeogenesis and ketogenesis due to their inability to use stored glycogen. The serum of fasted AIP mice showed increased concentrations of insulin and reduced glucagon levels. Specific over-expression of the PBGD protein in the liver tended to normalize circulating insulin and glucagon levels, stimulated hepatic glycogen catabolism and blocked ketone body production. Reduced glucose uptake was observed in the primary somatosensorial brain cortex of fasted AIP mice, which could be reversed by PBGD-liver gene delivery. In conclusion, AIP mice showed a different response to fasting as measured by altered carbohydrate metabolism in the liver and modified glucose consumption in the brain cortex. Glucose homeostasis in fasted AIP mice was efficiently normalized after restoration of PBGD gene expression in the liver.

Electrocardiogram in a patient with "acute intermittent porphyria"-triggered Takotsubo syndrome.

Takotsubo syndrome triggered by acute intermittent porphyria attack: An unusual stressor for catecholamine-induced cardiomyopathy.

Methotrexate and actinomycin D chemotherapy in a patient with porphyria: a case report.

Despite their broadly recommended use as chemotherapeutic agents, the porphyrogenicity of methotrexate and actinomycin D have not been confirmed. Accordingly, it is not known whether these agents are safe for use in patients with porphyria.

Influence of long-term treatment with hemin in the development of chronic renal failure in acute intermittent porphyria.


The experience of anesthesia and intensive care departments of Hematological center Russia for intensive care management in 13 patients with acute porphyria, from 1996 till 2013 was summarized ion this pape4: Main causes of life-threatening complications of acute porphyria and its frequency were revealed Advantages of mechanical lung ventilation in respiratory failure, algorithms of clinical nutrition, correction of water-electrolyte disorders were represented. Importance of kinesiotherapy in successful treatment in these category of patients was revealed. It is shown that the whole complex of intensive care methods with the specific pathogenetical therapy brings success in 84,6 % of patients.

Acute intermittent porphyria in a paediatric population in the region of Murcia: Phenotype and prevalence.

Acute intermittent porphyria: comorbidity and shared familial risks with schizophrenia and bipolar disorder in Sweden.

Acute intermittent porphyria (AIP) has been associated with schizophrenia in some studies, but prior research is limited by the absence of comparison populations. Here, we linked Swedish registers to examine the risk of schizophrenia and bipolar disorder in 717 individuals diagnosed with AIP and their first-degree relatives, compared with matched individuals without AIP and their first-degree relatives. Individuals with AIP had a fourfold increased risk of schizophrenia or bipolar disorder. Similarly, relatives of individuals with AIP had double the risk of schizophrenia or bipolar disorder, suggesting that these associations may be as a result of common genetic influences.

Challenges in the successful management of a case of acute intermittent porphyria in India.

Acute intermittent porphyria (AIP) is a rare metabolic disease involving a defect in haem biosynthesis resulting in the accumulation and excessive secretion of porphyrins and its precursors. Acute attacks present with episodes of severe abdominal pain, nausea, confusion and severe life-threatening seizures. A high index of suspicion is required for the initial diagnosis of AIP.