PubMed Health⌕ Search

Biomedical subjects

A L Tseng

Publications and source records attributed to A L Tseng.

10 recordsLinked to original sources

Non-nucleoside reverse transcriptase inhibitor failure impairs HIV-RNA responses to efavirenz-containing salvage antiretroviral therapy.

In a retrospective cohort study of salvage antiretroviral combination therapy including efavirenz, 60% of 51 patients were able to suppress HIV RNA by at least 1 log10 or to less than 50 copies/ml. A lack of the previous use of non-nucleoside reverse transcriptase inhibitors was the only factor predictive of response on multivariate analysis. No patient with a viral isolate with an increased IC50 to efavirenz by virtual phenotype had a virological response

Adult↗

Iritis associated with intravenous cidofovir.

OBJECTIVE: To report two patients with AIDS and cytomegalovirus retinitis who developed iritis after receiving intravenous cidofovir. Both experienced recurrent symptoms upon rechallenge. CASE SUMMARIES: Two HIV-positive patients with cytomegalovirus retinitis infections previously controlled with intravenous ganciclovir or foscarnet were treated with intravenous cidofovir. Symptoms of iritis developed after the second or third dose of cidofovir. One patient experienced symptoms unilaterally, while the other patient had bilateral symptoms. In both patients, the iritis resolved with topical ophthalmic therapy, but recurred following subsequent infusions of cidofovir. Therapy with cidofovir was discontinued, and no further recurrences of iritis were noted. One patient had post-inflammatory fixed dilated pupils. CONCLUSIONS: Iritis can uncommonly occur in patients receiving intravenous cidofovir and oral probenecid. With prompt drug discontinuation and administration of topical corticosteroids and/or mydriatic agents, symptoms are usually reversible.

AIDS-Related Opportunistic Infections↗

Significant interactions with new antiretrovirals and psychotropic drugs.

OBJECTIVE: To provide an update on relevant antiretroviral interactions and psychotropic medications for healthcare practitioners managing complex HIV-related pharmacotherapy. DATA SOURCES: Information was retrieved via a MEDLINE search (January 1966-September 1998) using MeSH headings human immunodeficiency virus, drug interactions, psychiatry, psychotropics, psychiatric illness, and names of medications commonly prescribed for the management of HIV infection. Abstracts of international and national conferences (until February 1999), review articles, textbooks, and references of all articles also were searched. STUDY SELECTION AND DATA EXTRACTION: Literature on pharmacokinetic interactions was considered for inclusion. Pertinent information was selected and summarized for discussion. In the absence of specific data, pharmacokinetic and pharmacodynamic properties were considered in order to predict the likelihood of potential drug interactions. DATA SYNTHESIS: All protease inhibitors and nonnucleoside reverse transcriptase inhibitors are substrates of the cytochrome P450 system and possess enzyme-inhibiting and/or -inducing properties. Psychotropic medications also possess similar metabolic characteristics and may interact with antiretrovirals. Modifications in drug selection, dose, or dosing regimen may be needed to ensure adequate antiretroviral concentrations and thus minimize the risk of incomplete viral suppression and/or development of drug resistance. In the absence of specific data, consideration of metabolic characteristics may assist practitioners in predicting the likelihood of possible interactions. RESULTS: The incidence and implications of antiretroviral drug interactions are reviewed. Practical management strategies are also discussed. Comprehensive tables on clinically significant interactions with antiretroviral combinations and with psychiatric medications are provided. CONCLUSIONS: Given the increasing use of multiple-drug therapy, the potential for drug interactions is extremely high. Drug interactions may lead to undesirable outcomes including subtherapeutic drug concentrations and risk of antiretroviral resistance. Practitioners need to consider pharmacokinetic, pharmacologic, therapeutic, and adherence factors when managing interactions with complex antiretroviral therapy.

Antipsychotic Agents↗

Management of drug interactions in patients with HIV.

OBJECTIVE: To provide a complication of relevant information on drug interactions to assist healthcare practitioners in managing complex HIV-related pharmacotherapy. DATA SOURCES: Information was retrieved via a MEDLINE search (January 1966-December 1996) using MeSH headings "human immunodeficiency virus," "drug interactions," and names of medications commonly prescribed for the management of HIV infection and related opportunistic infections. Abstracts of international and national conferences, review articles, textbooks, and references of all articles were also searched. STUDY SELECTION AND DATA EXTRACTION: All literature on pharmacokinetic or pharmacodynamic interactions was considered for inclusion. Pertinent information, as assessed by the authors, was selected and summarized for discussion. DATA SYNTHESIS: Drug disposition and/or pharmacologic effect may be affected either by HIV-related physiologic changes or by the presence of concomitant drug therapy. Modifications in drug selection, dosage, dosing regimen, or route of administration may be needed to avoid or manage drug-disease, drug-drug, or drug-food interactions. Management options may depend on the mechanism and the clinical significance of the interaction, the availability of therapeutic alternatives, patient convenience, and cost restrictions. In the absence of specific data, consideration of pharmacokinetic and pharmacodynamic characteristics to assist practitioners in predicting the likelihood of possible interactions was included. RESULTS: A comprehensive table of clinically significant drug interactions is provided. Drug interaction principles and practical management strategies are also discussed. CONCLUSIONS: The potential for drug interactions is extremely common, given the increasing complexity of managing patients infected with HIV. To avoid compromising therapeutic efficacy or increasing drug toxicity, practitioners need to be aware of potential interactions and are encouraged to use a systematic approach when managing patient drug therapy.

Drug Interactions↗

Anonymous HIV testing in the Canadian aboriginal population.

Reported numbers of acquired immunodeficiency syndrome cases among Canadian aboriginal peoples are currently relatively low. However, any increase in these numbers could have devastating human, social, and economic costs. Education and prevention of human immunodeficiency virus transmission are the most efficient and cost-effective measures available today. This paper discusses the role of anonymous HIV testing in effective HIV prevention in the Canadian aboriginal population.

Canada↗

Fetal genital effects of first-trimester sex hormone exposure: a meta-analysis.

OBJECTIVE: To determine if first-trimester exposure to sex hormones, and oral contraceptives (OCs) specifically, is associated with an increased risk of external fetal genital malformations. DATA SOURCES: MEDLINE and Science Citation Index data bases were searched for the years 1966-1992 for relevant English-language articles on first-trimester sex-hormone exposure and fetal genital changes. METHODS OF STUDY SELECTION: One hundred eighty-six articles were identified initially. Inclusion criteria were cohort or case-control studies, first-trimester sex-hormone exposure, and live infants or full-term stillborn infants with external genital malformations. Exclusion criteria were diethylstilbestrol exposure, spontaneous abortions, and teratogen exposure. DATA EXTRACTION AND SYNTHESIS: The Methods section of each study was reviewed independently by two authors and two outside reviewers, using the above criteria. Fourteen studies, seven cohort and seven case-control, involving 65,567 women, met the criteria for meta-analysis. Extracted data were entered into 2 x 2 tables. The overall summary odds ratio (OR) was 1.09 (95% confidence interval [CI] 0.90-1.32); subanalysis of OC exposure identified an OR of 0.98 (95% CI 0.24-3.94). CONCLUSION: There was no association between first-trimester exposure to sex hormones generally (or to OCs specifically) and external genital malformations. Thus, women exposed to sex hormones after conception may be assured there is no increased risk of fetal sexual malformation.

Case-Control Studies↗

Rifabutin-associated uveitis.

OBJECTIVE: To review rifabutin-associated uveitis and discuss the mechanism and potential role of drug interactions with clarithromycin and fluconazole in contributing to this adverse event. DATA SOURCES: A MEDLINE search (1991 through September 1994) of English-language literature using the main MeSH headings "rifabutin" and "uveitis" and the subheadings "adverse effects" and "chemically induced." Relevant articles also were selected from references of identified articles. Abstracts from recent medical conferences of infectious diseases, pharmacology, and HIV were screened for additional data. STUDY SELECTION AND DATA EXTRACTION: All articles and abstracts reporting uveitis potentially related to rifabutin were considered for inclusion. Fifty-four cases were identified. Pertinent information from the case reports, as judged by the authors, was selected and synthesized for discussion. DATA SYNTHESIS: Rifabutin is being prescribed increasingly for the treatment and prophylaxis of Mycobacterium avium complex (MAC) infection in the HIV-infected population. Uveitis was initially thought to be a rare, dose-limited complication of rifabutin therapy. In an early dose-ranging tolerance study, uveitis was associated with daily doses of 1200 mg or more. Because this toxicity appeared to be dose-related, lower dosages (300-600 mg/d) of rifabutin were selected for study in subsequent clinical trials. More recent reports noting the association of uveitis with these lower dosages of rifabutin have raised concerns about the prevalence of this adverse event. In the 54 identified cases, patients presented with symptoms of unilateral or bilateral uveitis from 2 weeks to more than 7 months following initiation of rifabutin therapy. In all reported cases, patients were receiving concurrent therapy with clarithromycin and/or fluconazole, both of which have inhibitory effects on rifabutin metabolism. In most cases, uveitis resolved within 1-2 months following discontinuation of rifabutin with or without administration of topical corticosteroids. CONCLUSIONS: Rifabutin is prescribed frequently for the prophylaxis and treatment of MAC infection, especially in patients with HIV. Uveitis is a rare, dose-related toxicity of this therapy. The risk of rifabutin-associated uveitis may be increased in patients receiving concurrent therapy with clarithromycin or fluconazole because of drug interactions. Patients receiving therapy with combinations of any of these agents should be warned about signs and symptoms of uveitis and be monitored closely for the development of rifabutin toxicity. If uveitis develops, rifabutin therapy should be discontinued promptly.

Anti-Bacterial Agents↗