Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0344232 (blurred vision)
 2,072 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Reported is the case of a 24-year-old Finnish woman who developed malignant hypertension while taking an oral contraceptive (OC) that contained 30 mcg of ethinyl estradiol. She presented with blurred vision, but reported no other remarkable signs or symptoms during the 5 months in which she had been using OCs. Laboratory tests at admission revealed incomplete systemic lupus erythematosus (SLE) with DNA antibodies and high levels of antiphospholipid antibodies. Her blood pressure was 220-140 mmHg. OC use was discontinued and antihypertensive treatment initiated, with good results. 2 years later, however, the patient developed epileptic seizures and an area of local atrophy in the cerebellum was identified through computerized tomography. In the 4-6th years after initial presentation, the patient experienced 3 miscarriages, all at 7-8 weeks of gestation. 1 year after presentation, the patient satisfied 4 of the criteria for SLE (positive DNA and antiphospholipid antibodies, thrombocytopenia, leukopenia, and proteinuria). At present, the patient's symptoms are being controlled with carbamazepine and metroprolol. The patient's older sister, who had never used OCs, had SLE. It appears that high levels of antiphospholipid antibodies are an additional risk factor for the development of vascular complications in OC users but are not induced by OCs. Similarly, while OCs are not believed to cause SLE, they can exacerbate the disease or unmask a lupus diathesis.
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PMID:Malignant hypertension and antiphospholipid antibodies as presenting features of SLE in a young woman using oral contraceptives. 174 6

The three best-described genetic polymorphisms of drug metabolism--the debrisoquin/sparteine type of oxidative polymorphism (hereafter referred to as the debrisoquin polymorphism), the polymorphism of N-acetylation, and the mephenytoin type of oxidative polymorphism--are reviewed. For all three polymorphisms, the poor-metabolizer phenotype is inherited as an autosomal recessive trait. The debrisoquin and mephenytoin oxidative polymorphisms involve defects in two separate cytochrome P450 enzymes. The prevalence of the poor-metabolizer phenotype for debrisoquin ranges between 2% and 10% for groups of various ethnic origins. The poor-metabolizer phenotype for mephenytoin comprises about 5% of the Caucasian population and about 20% of the Japanese population. N-acetyltransferase is a cytosolic enzyme whose clinical polymorphism was discovered using isoniazid as the substrate probe. The prevalence of the slow-acetylator phenotype among American and European Caucasian and American black groups is about 50%; among the Japanese it is about 10%. More than 20 agents are substrates for debrisoquin hydroxylase, about 15 for N-acetyltransferase, and 3-5 for mephenytoin. In poor metabolizers, debrisoquin can cause hypotension, and sparteine can cause blurred vision, headache, and dizziness. Clinical consequences of the slow-acetylator phenotype include increased susceptibility to systemic lupus erythematosus induced by procainamide and hydralazine, peripheral neuropathy induced by isoniazid, hydralazine, and dapsone, and sulfasalazine-induced dose-related leukopenia, nausea, vomiting, headache, and vertigo. After administration of mephenytoin, poor metabolizers have increased somnolence and intellectual impairment. Awareness of genetic polymorphisms of drug metabolism should improve understanding of interindividual variability in drug disposition and response.
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PMID:Polymorphic drug metabolism. 268 60

Topotecan (NSC 609099) is a camptothecin analogue that demonstrated activity against a variety of human tumors in preclinical studies. A phase II trial was performed with topotecan given to patients with locally advanced or metastatic adenocarcinoma of the stomach. Topotecan was administered IV Bolus over 30 minutes on a daily X 5 schedule, every three weeks, with a starting dose of 1.5 mg/m2. Twenty patients were entered onto the study, all of whom were eligible. All patients were evaluable for toxicities. Half of these patients experienced at least one Grade 4 hematologic toxicity, comprised of either granulocytopenia or leukopenia (4 patients with both, 3 patients with grade 4 granulocytopenia, and 2 patients with only grade 4 leukopenia). Other non-life threatening (Grade 3) toxicities included nausea (2 patients), weakness (2 patients), weight loss (1 patient), blurred vision (1 patient), diarrhea (1 patient) and malaise/fatigue/lethargy (1 patient). Two patients achieved a partial response, for an overall response rate of 10% (95% confidence interval of 1.2 to 31.7%). The median survival for the 20 patients was five months.
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PMID:Phase II trial of topotecan in advanced gastric cancer: a Southwest Oncology Group study. 938 50