Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acute intermittent prophyria (AIP) is an autosomal dominant disease that results from a defect in the enzyme porphobilinogen deaminase. Acute intermittent porphyria is the most common of hepatic porphyrias and can tax the therapeutic capabilities of the physician to the limit. Motor weakness is a major feature of an acute attack, and flaccid paralysis of all extremities can occur rapidly, within a matter of days. The acute attacks may be life threatening. Hematin (Heme Arginate) should be given early during an acute attack to prevent neurologic sequel. Hemodialysis and hemoperfusion have been tried in the treatment of acute attacks of AIP with success. As hematin is not available in India, a severe acute attack of AIP in a patient was managed with hemodialysis successfully. Later, hematin was imported and provided to the patient. An 18-year-old girl was admitted to our hospital with recurrent abdominal pain and 2 episodes of convulsions. She had undergone an appendectomy earlier at another hospital for abdominal pain. On evaluation, she had hyponatremia, episodic abnormal behavior, generalized muscle pain, hypertension, and sinus tachycardia. In view of the above clinical picture, a clinical diagnosis of acute intermittent porphyria was made. Her 24-hr urinary porphobilinogen was 90.8 mg/day (<2 mg-normal) and alpha amino levalunic acid was 108.8 mg/day (1-7 mg-normal), consistent with the diagnosis. Her hyponatremia was corrected. Arrangements were made to import hematin and she was managed with dextrose infusion. Meanwhile, she developed flaccid quardriparesis with urinary incontinence and bulbar palsy. Her brain MRI was normal. Her nerve conduction study was suggestive of motor radiculoneuropathy. Specific treatment for severe porphyric crisis was planned. She failed to improve with dextrose infusion alone. As hematin was not readily available in the country, other therapeutic options were considered. As few case reports of AIP being successfully treated with hemodialysis were available, the option of dialytic support was explained to the family. After procuring informed consent, she was subjected to hemodialysis for 4 hr in the first day, increasing to 6 hr a day for the next 6 days. Her abdominal pain and myalgia subsided on the third day of dialysis. Her lower limb muscle power improved and she became ambulant by the fourth day. Urinary retention improved within 4 days. Hematin was imported by then from the United States. Later, 2 doses of hematin (4 mg/kg-160 mg in 20% albumin) were given via a central vein. She was maintained on physiotherapy. Repeat nerve conduction study revealed recovery. She has been provided with a list of drugs that have to be avoided. Currently, she is on outpatient follow-up with occasional abdominal pain, which subsides with intravenous dextrose therapy.
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PMID:Hemodialysis: a therapeutic option for severe attacks of acute intermittent porphyria in developing countries. 1827 38

We report a 36-year-old woman presenting with hypertensive encephalopathy followed by bulbar palsy and quadriplegia. After an extensive screening for secondary causes of hypertension, the patient was suspected of having pheochromocytoma due to increased levels of catecholamines in the plasma and the urine, and positive (131)I-metaiodobenzylguanidine (MIBG) accumulation in the gallbladder. However, MIBG accumulation was not reproducible without any tumors accompanying this accumulation in the gallbladder. A diagnosis of acute intermittent porphyria was finally confirmed based on the characteristic pictures, increased urinary excretion of porphobilinogen, and identification of a heterozygous missense mutation of R173W in the hydroxymethylbilane synthase gene. This case highlights a pitfall in utilizing MIBG to detect a source of excessive catecholamine and also suggests the importance of having a complete clinical history and extensive work-up of any possible differential diagnosis. We also review the potential mechanism by which false-positive MIBG accumulation occurs.
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PMID:False-positive accumulation of metaiodobenzylguanidine in a case with acute intermittent porphyria. 2153 27

Acute intermittent porphyria (AIP) is a rare autosomal dominant disorder of heme biosynthesis in liver due to deficiency of porphobilinogen deaminase enzyme. Clinically, AIP is dominated by a colicky type pain, which does not subside after taking usual analgesics. Additional frequent symptoms are vomiting, hypertension, peripheral neuropathy, seizures, depression, delirium and coma. This paper reported a case of a twenty-five- year-old female patient, who had undergone a period of six days between the first presentation to the medical department and the diagnosis confirmation. It has accentuated possible mistakes in symptomatic therapy administration as well as dangers of a delayed diagnosis.
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PMID:Differential diagnosis of acute abdominal pain - acute intermittent porphyria. 2184 59

Acute intermittent porphyria (AIP) is due to a deficiency of the third enzyme, the hydroxymethylbilane synthase, in heme biosynthesis. It manifests with occasional neuropsychiatric crises associated with overproduction of porphyrin precursors, aminolevulinic acid and porphobilinogen. The clinical criteria of an acute attack include the paroxysmal nature and various combinations of symptoms, such as abdominal pain, autonomic dysfunction, hyponatremia, muscle weakness, or mental symptoms, in the absence of other obvious causes. Intensive abdominal pain without peritoneal signs, acute peripheral neuropathy, and encephalopathy usually with seizures or psychosis are the key symptoms indicating possible acute porphyria. More than fivefold elevation of urinary porphobilinogen excretion together with typical symptoms of an acute attack is sufficient to start a treatment. Currently, the prognosis of the patients with AIP is good, but physicians should be aware of a potentially fatal outcome of the disease. Mutation screening and identification of type of acute porphyria can be done at the quiescent phase of the disease. The management of patients with AIP include following strategies: A, during an acute attack: 1) treatment with heme preparations, if an acute attack is severe or moderate; 2) symptomatic treatment of autonomic dysfunctions, polyneuropathy and encephalopathy; 3) exclusion of precipitating factors; and 4) adequate nutrition and fluid therapy. B, during remission: 1) exclusion of precipitating factors (education of patients and family doctors), 2) information about on-line drug lists, and 3) mutation screening for family members and education about precipitating factors in mutation-positive family members. C, management of patients with recurrent attacks: 1) evaluation of the lifestyle, 2) evaluation of hormonal therapy in women, 3) prophylactic heme therapy, and 4) liver transplantation in patients with severe recurrent attacks. D, follow-up of the AIP patients for long-term complications: chronic hypertension, chronic kidney insufficiency, chronic pain syndrome, and hepatocellular carcinoma.
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PMID:An update of clinical management of acute intermittent porphyria. 2636 3

Acute intermittent porphyria (AIP) and ichthyosis vulgaris both are autosomal dominant disorders with incomplete penetrance caused by the deficiency of porphobilinogen deaminase enzyme and filaggrin protein, respectively. We report a rare case of a 9-year-old boy having two genetic diseases with an unclear association. An acute attack of AIP is characterized by gastrointestinal symptoms and neuropsychiatric manifestations. Although rare in the first decade of life, the presence of reddish urine with a typical presentation such as abdominal pain, hypertension, seizure, and paresthesias lead us to the diagnosis of AIP. The precipitating factor in the present case was prolonged fasting in Ramadan.
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PMID:A rare case of acute intermittent porphyria with ichthyosis vulgaris in a young boy. 2991 73

Acute intermittent porphyria (AIP) results from haploinsufficiency of porphobilinogen deaminase (PBGD), the third enzyme in the heme biosynthesis pathway. Patients with AIP have neurovisceral attacks associated with increased hepatic heme demand. Phenobarbital-challenged mice with AIP recapitulate the biochemical and clinical characteristics of patients with AIP, including hepatic overproduction of the potentially neurotoxic porphyrin precursors. Here we show that intravenous administration of human PBGD (hPBGD) mRNA (encoded by the gene HMBS) encapsulated in lipid nanoparticles induces dose-dependent protein expression in mouse hepatocytes, rapidly normalizing urine porphyrin precursor excretion in ongoing attacks. Furthermore, hPBGD mRNA protected against mitochondrial dysfunction, hypertension, pain and motor impairment. Repeat dosing in AIP mice showed sustained efficacy and therapeutic improvement without evidence of hepatotoxicity. Finally, multiple administrations to nonhuman primates confirmed safety and translatability. These data provide proof-of-concept for systemic hPBGD mRNA as a potential therapy for AIP.
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PMID:Systemic messenger RNA as an etiological treatment for acute intermittent porphyria. 3102 36

Mutations in hydroxymethylbilane synthase (HMBS) cause acute intermittent porphyria (AIP), an autosomal dominant disease where typically only one HMBS allele is mutated. In AIP, the accumulation of porphyrin precursors triggers life-threatening neurovisceral attacks and at long-term, entails an increased risk of hepatocellular carcinoma, kidney failure, and hypertension. Today, the only cure is liver transplantation, and a need for effective mechanism-based therapies, such as pharmacological chaperones, is prevailing. These are small molecules that specifically stabilize a target protein. They may be developed into an oral treatment, which could work curatively during acute attacks, but also prophylactically in asymptomatic HMBS mutant carriers. With the use of a 10,000 compound library, we identified four binders that further increased the initially very high thermal stability of wild-type HMBS and protected the enzyme from trypsin digestion. The best hit and a selected analog increased steady-state levels and total HMBS activity in human hepatoma cells overexpressing HMBS, and in an Hmbs-deficient mouse model with a low-expressed wild-type-like allele, compared to untreated controls. Moreover, the concentration of porphyrin precursors decreased in liver of mice treated with the best hit. Our findings demonstrate the great potential of these hits for the development of a pharmacological chaperone-based corrective treatment of AIP by enhancing wild-type HMBS function independently of the patients' specific mutation.
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PMID:A Pharmacological Chaperone Therapy for Acute Intermittent Porphyria. 3181 Aug 63