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Biomedical subjects

W G Powderly

Publications and source records attributed to W G Powderly.

At least 109 records · Page 6Linked to original sources

Blastomycosis in patients with the acquired immunodeficiency syndrome.

OBJECTIVE: To describe the clinical, demographic, radiographic, diagnostic, and therapeutic aspects of blastomycosis in patients with the acquired immunodeficiency syndrome (AIDS). DESIGN: A retrospective survey. SETTING: Ten university medical centers and community hospitals, six in geographic areas endemic for Blastomyces dermatitidis, and four outside the endemic area. PATIENTS: We identified 15 patients with blastomycosis and positive serologic test results for human immunodeficiency virus (HIV). MEASUREMENTS: A diagnosis of blastomycosis was based on a positive culture (14 patients) or typical histopathologic features (one patient) for B. dermatitidis in clinical specimens. RESULTS: Twelve of 15 patients had a previous or concomitant AIDS-defining illness at the time of diagnosis of blastomycosis, and only one patient had a CD4 lymphocyte count of greater than 200 cells/mm3. Two patterns of disease emerged: localized pulmonary involvement (seven patients), and disseminated or extrapulmonary blastomycosis (eight patients). Central nervous system involvement was common (40%). Six patients died within 21 days of presentation with blastomycosis, including four patients with disseminated and two with fulminant pulmonary disease. Among the nine patients who survived longer than 1 month, all received amphotericin B as initial antifungal therapy, and most received subsequent therapy with ketoconazole. Only two of these nine patients died with evidence of progressive blastomycosis. CONCLUSIONS: Blastomycosis is a late and frequently fatal infectious complication in a few patients with AIDS. In these patients, overwhelming disseminated disease including involvement of the central nervous system is common, and it is associated with a high early mortality. Initial therapy with amphotericin B is appropriate in patients with AIDS and presumptive blastomycosis.

Acquired Immunodeficiency Syndrome↗

A controlled trial of fluconazole or amphotericin B to prevent relapse of cryptococcal meningitis in patients with the acquired immunodeficiency syndrome. The NIAID AIDS Clinical Trials Group and Mycoses Study Group.

BACKGROUND: After primary treatment for cryptococcal meningitis, patients with the acquired immunodeficiency syndrome (AIDS) require some form of continued suppressive therapy to prevent relapse. METHODS: We conducted a multicenter, randomized trial that compared fluconazole (200 mg per day given orally) with amphotericin B (1 mg per kilogram of body weight per week given intravenously) in patients with AIDS who had completed primary therapy for cryptococcal meningitis with amphotericin B (greater than or equal to 15 mg per kilogram). To be eligible, patients had to have at least two negative cultures of cerebrospinal fluid immediately before randomization. The primary end point was relapse of cryptococcal disease as confirmed by biopsy or culture. RESULTS: Of 218 patients initially enrolled, 119 were assigned to fluconazole and 99 to amphotericin B. Twenty-three patients were found not to have met the entry criteria; six other patients assigned to amphotericin B did not receive it and were lost to follow-up. Of the remaining 189 patients, after a median follow-up of 286 days 14 of 78 receiving amphotericin B (18 percent) and 2 of 111 assigned to fluconazole (2 percent) had relapses of symptomatic cryptococcal disease (P less than 0.001 by Fisher's exact test). There was a difference of 19 percent in the estimated probability of remaining relapse-free at one year between the fluconazole group (97 percent) and the amphotericin B group (78 percent) (95 percent confidence interval, 7 percent to 31 percent; P less than 0.001). Serious drug-related toxicity was more frequent in the amphotericin B group (P = 0.02), as were bacterial infections (P = 0.004) and bacteremia (P = 0.002). CONCLUSIONS: Fluconazole taken by mouth is superior to weekly intravenous therapy with amphotericin B to prevent relapse in patients with AIDS-associated cryptococcal meningitis after primary treatment with amphotericin B.

Acquired Immunodeficiency Syndrome↗

Comparison of amphotericin B with fluconazole in the treatment of acute AIDS-associated cryptococcal meningitis. The NIAID Mycoses Study Group and the AIDS Clinical Trials Group.

BACKGROUND: Intravenous amphotericin B, with or without flucytosine, is usually standard therapy for cryptococcal meningitis in patients with the acquired immunodeficiency syndrome (AIDS). Fluconazole, an oral triazole agent, represents a promising new approach to the treatment of cryptococcal disease. METHODS: In a randomized multicenter trial, we compared intravenous amphotericin B with oral fluconazole as primary therapy for AIDS-associated acute cryptococcal meningitis. Eligible patients, in all of whom the diagnosis had been confirmed by culture, were randomly assigned in a 2:1 ratio to receive either fluconazole (200 mg per day) or amphotericin B. Treatment was considered successful if the patient had had two consecutive negative cerebrospinal fluid cultures by the end of the 10-week treatment period. RESULTS: Of the 194 eligible patients, 131 received fluconazole and 63 received amphotericin B (mean daily dose, 0.4 mg per kilogram of body weight in patients with successful treatment and 0.5 mg per kilogram in patients with treatment failure; P = 0.34). Treatment was successful in 25 of the 63 amphotericin B recipients (40 percent; 95 percent confidence interval, 26 percent to 53 percent) and in 44 of the 131 fluconazole recipients (34 percent; 95 percent confidence interval, 25 percent to 42 percent) (P = 0.40). There was no significant difference between the groups in overall mortality due to cryptococcosis (amphotericin vs. fluconazole, 9 of 63 [14 percent] vs. 24 of 131 [18 percent]; P = 0.48); however, mortality during the first two weeks of therapy was higher in the fluconazole group (15 percent vs. 8 percent; P = 0.25). The median length of time to the first negative cerebrospinal fluid culture was 42 days (95 percent confidence interval, 28 to 71) in the amphotericin B group and 64 days (95 percent confidence interval, 53 to 67) in the fluconazole group (P = 0.25). Multivariate analyses identified abnormal mental status (lethargy, somnolence, or obtundation) as the most important predictive factor of a high risk of death during therapy (P less than 0.0001). CONCLUSIONS: Fluconazole is an effective alternative to amphotericin B as primary treatment of cryptococcal meningitis in patients with AIDS. Single-drug therapy with either drug is most effective in patients who are at low risk for treatment failure. The optimal therapy for patients at high risk remains to be determined.

Acquired Immunodeficiency Syndrome↗

Therapy for cryptococcal meningitis in patients with AIDS.

Treatment of cryptococcal meningitis in patients with AIDS with amphotericin B plus flucytosine is associated with a failure rate of 20%-30%. In the absence of chronic suppressive therapy, 40%-60% of patients develop recurrent disease. Recent comparative studies have evaluated fluconazole, a new triazole antifungal agent. In primary therapy, fluconazole is associated with response rates of 35%-60%, which are equivalent to those seen with amphotericin B alone. However, a smaller study suggested that amphotericin B plus flucytosine was superior to fluconazole alone. Both studies identified risk factors associated with a poor outcome; these factors include lethargy or obtundation at presentation, a high titer of cryptococcal antigen titer in the cerebrospinal fluid, and a low leukocyte count in the cerebrospinal fluid. Fluconazole is highly effective in suppressing relapses of cryptococcal meningitis. Itraconazole has been investigated less extensively in the treatment of cryptococcosis but offers promise. Future studies need to address alternative approaches to the management of acute cryptococcal disease and primary prophylaxis for cryptococcal infection in patients with AIDS.

Acquired Immunodeficiency Syndrome↗

Failure of prophylactic ganciclovir to prevent cytomegalovirus disease in recipients of lung transplants.

In an effort to prevent cytomegalovirus (CMV) pneumonitis, seven consecutive CMV-seronegative lung transplant recipients of organs from seropositive donors (D+/R-) were given ganciclovir, 2.5-5 mg/kg intravenously twice daily for the first 10-21 days after transplantation, and commercial polyvalent immune globulin, 200-400 mg/kg every 7-14 days intravenously, for the first 2-3 weeks after transplantation. This regimen was followed by oral acyclovir. Six patients developed CMV viremia and all developed CMV pneumonitis. Viremia occurred later in these patients compared with D+/R- patients who received alternative forms of CMV prophylaxis or CMV-seropositive recipients who received no specific prophylaxis (P = .023 and P = .021, respectively). There was no statistical difference in incidence or time to onset of CMV pneumonitis. When given as described, prophylactic ganciclovir and immune globulin followed by oral acyclovir may have delayed CMV viremia but did not prevent it or pneumonitis in high-risk lung transplant recipients.

Acyclovir↗

Molecular typing of candida albicans isolated from oral lesions of HIV-infected individuals.

OBJECTIVE: To evaluate the epidemiology of Candida albicans infection in HIV-infected patients with oral lesions using molecular techniques. METHODS: Thirty-nine isolates from HIV-positive patients with oral candidiasis were examined using two DNA probes (a Histoplasma capsulatum ribosomal DNA probe that cross-hybridizes with C. albicans and a C. albicans strain-specific probe derived from repetitive sequence DNA). C. albicans obtained from the oral cavity of patients receiving cytotoxic chemotherapy was used as controls. RESULTS: Using the H. capsulatum ribosomal DNA probe, isolates were shown to members of many distinct classes of C. albicans. Forty-nine per cent (19 out of 39) of isolates were members of the same class; however, 46% (6 out of 13) of control C. albicans isolates were also members of this class. Further analysis of the class-restricted isolates from the HIV-infected patients using the C. albicans strain-specific probe showed that these could be further separated into distinct strains. CONCLUSIONS: These data indicate that strains of C. albicans that cause oral candidiasis in HIV-positive individuals are not clonally restricted and are similar to those colonizing the oral cavity of other severely immunocompromised hosts. Most patients appear to be infected with unique strains of C. albicans.

Blotting, Southern↗

Two cases of blastomycosis from a common source: use of DNA restriction analysis to identify strains.

Two friends, one with AIDS, developed severe pulmonary blastomycosis but differed markedly in clinical course. The human immunodeficiency virus-negative patient responded completely to ketoconazole; the patient with AIDS died of progressive disseminated infection despite treatment with fluconazole and amphotericin B. Epidemiologic investigation suggested a common source of infection, but serologic evaluation and environmental cultures were unrevealing. EcoRI digestion of the Blastomyces dermatitidis isolates showed identical restriction fragment patterns that differed from patterns obtained from other clinical isolates. Analysis using a Histoplasma capsulatum ribosomal DNA probe that cross-hybridizes with B. dermatitidis showed that the isolates from the two patients were identical and different from others. Thus, the patients were probably infected with the same strain, possibly from a common source. These data indicate the critical role of cellular immunity in patients with blastomycosis, show that there are multiple genotypes of B. dermatitidis, and suggest that DNA restriction analysis is a useful epidemiologic tool.

Acquired Immunodeficiency Syndrome↗

The safety and efficacy of zidovudine (AZT) in the treatment of subjects with mildly symptomatic human immunodeficiency virus type 1 (HIV) infection. A double-blind, placebo-controlled trial. The AIDS Clinical Trials Group.

OBJECTIVE: To evaluate the efficacy and safety of zidovudine early in the treatment of human immunodeficiency virus type 1 (HIV) infection. DESIGN: A double-blind, randomized, placebo-controlled trial with subject stratification by pretreatment CD4 T lymphocyte counts. SETTING: Multicenter trial at AIDS Clinical Trial units. SUBJECTS: Seven hundred eleven subjects with mildly symptomatic HIV infection. INTERVENTION: Three hundred fifty-one subjects were assigned to placebo and 360 to zidovudine, 200 mg orally every 4 hours. The median duration of follow-up was 11 months. MEASUREMENTS AND MAIN RESULTS: Fifty-one subjects developed the acquired immunodeficiency syndrome (AIDS), advanced AIDS-related complex, or death as a first critical event. For the stratum of subjects with more than 200 but less than 500 CD4 T lymphocytes/mm3 before treatment, 34 events occurred in placebo recipients and 12 in zidovudine recipients (P = 0.0002; relative risk [RR] estimate, 3.23 [95% CI, 1.67 to 6.24]). For the stratum of subjects with 500 to 799 CD4 T lymphocytes/mm3 before treatment, 2 events occurred in placebo recipients and 3 in zidovudine recipients. Candidiasis at study entry independently increased the risk for having an event (P = 0.005; RR estimate, 2.3 [95% CI, 1.29 to 4.12]); HIV antigenemia at study entry also increased this risk (P = 0.01; RR estimate, 2.1 [95% CI, 1.2 to 3.8]). Significant differences between the treatment groups in CD4 T-lymphocyte counts occurred in subjects with more than 200 but less than 500 CD4 T lymphocytes/mm3 after 4 weeks of therapy (P = 0.002). Differences persisted through week 52. Less prominent changes occurred in subjects with 500 or more CD4 T lymphocytes/mm3. Serum levels of HIV antigen decreased significantly in zidovudine recipients. Serious anemia and neutropenia occurred in 5% and 4% of zidovudine recipients, respectively, and in 0% and 1% of placebo recipients, respectively. CONCLUSION: Zidovudine delayed progression of HIV disease and produced little toxicity in subjects with mildly symptomatic HIV disease and less than 500 CD4 T lymphocytes/mm3.

AIDS-Related Complex↗

Fungal infections in patients infected with HIV.

HIV-positive patients are at risk for a number of serious fungal infections. The author reviews the common fungal infections and stresses the importance of early detection and appropriate treatment.

Acquired Immunodeficiency Syndrome↗

Initial clinical management of the HIV-infected patient.

For the primary care physician, treatment of HIV-infected patients often centers on the stage of illness at which the patient first seeks care. Disease staging, which uses symptoms in its classification scheme, thus leads to evaluation and selection of appropriate therapy. This is the second article in a series from the Washington University AIDS Clinical Trials Unit.

CD4-Positive T-Lymphocytes↗

Zidovudine.

Zidovudine, or azidothymidine (AZT), is the only drug currently approved for treating patients with HIV infection. Though it effectively inhibits the disease, the drug's use is associated with a number of side effects, some grave. Management of zidovudine therapy and its side effects is highlighted. This is the third article in a series from the Washington University AIDS Clinical Trials Unit.

Acquired Immunodeficiency Syndrome↗

Human immunodeficiency virus infection. Clinical diagnosis.

Primary care physicians are likely to see HIV-infected individuals well before they develop full-blown AIDS or even AIDS-related complex. The author presents an overview of the symptoms that may appear in so-called "asymptomatic" patients with human immunodeficiency virus infection.

AIDS-Related Complex↗

Suppressor T cells regulating the cell-mediated immune response to Pseudomonas aeruginosa can be generated by immunization with anti-bacterial T cells.

We previously demonstrated that immunization with low (10 micrograms) doses of high m.w. polysaccharide from the gram-negative bacterium Pseudomonas aeruginosa generates T cells that suppress the ability of antibacterial T cells (Tab) to protect against bacterial infection. The current studies indicate that Ts cells with properties identical to those elicited by low dose polysaccharide immunization can be generated by immunization with Tab. Tab-elicited Ts cells can abrogate in vivo induction and in vitro and in vivo expression of antibacterial T cell activity. Tab-elicited Ts are Ag-specific and H-2 restricted in their suppressor activity. Non-immune T cells fail to elicit suppressor activity. These studies provide additional evidence that the protective T cell response to P. aeruginosa is controlled by a network of T cells that are probably recognizing idiotypic determinants on P. aeruginosa-immune T and B cells.

Animals↗