Synthetic-peptide-based enzyme-linked immunosorbent assay for screening human serum or plasma for antibodies to human immunodeficiency virus type 1 and type 2.

A synthetic-peptide-based enzyme-linked immunosorbent assay (EIA) capable of screening for antibodies to both human immunodeficiency virus type 1 (HIV-1) and HIV-2 has been developed for use in blood banks and diagnostic laboratories. Microtiter wells are coated with two synthetic peptides, one corresponding to the highly conserved envelope region of HIV-1 and another corresponding to the conserved envelope region of HIV-2. Overall, sensitivity was 100% in 303 individuals diagnosed with AIDS and 96 individuals diagnosed with AIDS-related complex, 14.8% in a study of 500 high-risk group members, 99.9% in 600 EIA repeatedly reactive (RR)-HIV-1 Western blot (WB)-positive repository specimens, and 100% for 222 geographically diverse HIV-1 specimens and 216 confirmed HIV-2-positive specimens evaluated. The specificity was determined to be 99.72% for a total of 13,004 serum and plasma samples from random volunteer donors evaluated across five blood banks. Forty donors who were found to be EIA RR-WB indeterminate but nonreactive on the United Biomedical, Inc., test (UBI HIV 1/2 EIA) were prospectively followed as an additional measure of specificity. None of the 40 low-risk cases evolved into a positive WB pattern at follow-up. The sensitivity and specificity of this new assay are comparable to those of other Food and Drug Administration-licensed HIV-1 and HIV-1-HIV-2 assays that are currently available in the United States. The UBI HIV 1/2 EIA affords laboratories another choice in the detection of antibodies for HIV-1 and HIV-2 with a test based on an alternative antigen format.

Immune compromise and prevalence of Candida vulvovaginitis in human immunodeficiency virus-infected women.

OBJECTIVE: To investigate the effect of human immunodeficiency virus (HIV) infection on vaginal yeast colonization and symptomatic vulvovaginitis and to explore the effects of immune compromise on these conditions in HIV-positive women. METHODS: Between September 1991 and May 1993, 223 HIV-positive women without AIDS-defining conditions were enrolled for prospective follow-up and compared with 289 HIV-negative women enrolled in a concurrent study. Standardized gynecologic assessment was carried out. RESULTS: Cultures from 81 of 223 (36%) HIV-positive women and 72 of 289 (25%) HIV-negative women were positive for any yeast. The most commonly isolated yeasts were Candida albicans and Torulopsis glabrata; the proportion of non-C albicans isolates (26%) did not differ by serostatus. The rates of C albicans colonization and vulvovaginitis among immunocompetent (CD4 count at least 500 cells/mm3) HIV-positive women did not differ from those among HIV-negative women. Among HIV-positive women, risks for colonization and for symptomatic vulvovaginitis were increased approximately threefold and fourfold respectively, in women with CD4 counts below 200 cells/mm3 compared with either immunocompetent HIV-positive women or HIV-negative women. CONCLUSION: The yeast species isolated from HIV-positive and HIV-negative women were similar. Rates of vaginal colonization and vaginitis were similar among nonimmunocompromised HIV-positive women and HIV-negative women. Elevated rates of yeast colonization and vaginitis were not seen among this population of HIV-infected women before immune compromise. Both vaginal colonization and symptomatic vaginitis increased with immune compromise among HIV-positive women, especially at CD4 counts below 200 cells/mm3.

Recovery of cytomegalovirus and herpes simplex virus from upper and lower genital tract specimens obtained from women with pelvic inflammatory disease.

Lower genital tract specimens and endometrial biopsies from 147 women with pelvic inflammatory disease (PID) and surgical specimens (fallopian tubes, ovaries, or both) from 22 women with PID and 37 women without PID were cultured for cytomegalovirus (CMV) and herpes simplex virus (HSV), as well as for organisms commonly associated with PID. CMV was isolated from 39 cervical or endometrial samples from 30 (20.4%) of 147 women with PID and from ovaries or fallopian tubes from 5 (22.7%) of 22 women with PID, but CMV was not recovered from surgical specimens obtained from 37 women undergoing surgery for tubal ligation, ectopic pregnancy, or other gynecologic conditions (P = .005). HSV was isolated from cervical samples obtained from 5 (3.4%) of 147 women with PID but not from any endometrial or surgical specimens. These data suggest that CMV, but not HSV, may contribute to the pathogenesis of PID in some patients.

Factors associated with cytomegalovirus infection among human immunodeficiency virus type 1-seronegative and -seropositive women from an urban minority community.

Cytomegalovirus (CMV) seroprevalence and genital tract shedding in human immunodeficiency virus (HIV)-seronegative and HIV-seropositive women from an urban minority community were investigated. CMV seropositivity was high in both groups: 181 (95.2%) of 190 HIV-negative and 158 (90.3%) of 175 HIV-positive subjects. Cervicovaginal shedding was detected in 8 (4.4%) CMV-positive HIV-negative subjects and 31 (19.6%) HIV-positive subjects (odds ratio [OR], 5.28; P < .001). Multiple logistic regression analysis revealed that CMV shedding was independently associated with younger age (OR = 0.90; P < .001) and concurrent Chlamydia trachomatis or Neisseria gonorrhoeae infection (OR = 3.60; P = .08). However, shedding was observed over a broad age range in HIV-positive subjects, with 54.8% of shedders being > or = 30 years old. Among HIV-positive subjects, CMV shedding was also associated with decreased CD4 cell counts (P = .04) and, compared with HIV-negative subjects, was significantly higher (P < .001) among subjects with CD4 cell counts < 500 x 10(6)/L (26.5% in subjects with counts < or = 200 and 22.1% in subjects with counts of 201-499 x 10(6)/L).

Comparison of the Syva MicroTrak enzyme immunoassay and Gen-Probe PACE 2 with cell culture for diagnosis of cervical Chlamydia trachomatis infection in a high-prevalence female population.

Culture is currently considered the "gold standard" for detecting Chlamydia trachomatis infections. We evaluated the Syva MicroTrak enzyme immunoassay (EIA) and Gen-Probe PACE 2 tests, which detect chlamydial antigens and rRNA, respectively. These assays were compared with each other and with culture for the detection of C. trachomatis in cervical specimens obtained from 217 women attending a clinic for sexually transmitted diseases. The prevalence of infection was 22.1% by culture. The sensitivity, specificity, and positive and negative predictive values were 79.2, 98.2, 92.6, and 94.3%, respectively, for EIA. For PACE 2, the respective values were 77.1, 97.6, 90.1, and 93.7%. After corrections for two false-negative cultures, the sensitivities and specificities were 80 and 99.4%, respectively, for the EIA and 78 and 98.8%, respectively, for the probe assay. Quantitative evaluation of the results showed that false-negative results with either assay were associated with cultures that had low inclusion counts or were negative without subpassage. Analysis of nonculture results revealed that 2.3% of the EIA results and 4.6% of the probe assay results were within +/- 30% of the respective assay cutoff values. These included four false-negative (one EIA and three probe) and two false-positive (one EIA and one probe) results. The Syva MicroTrak EIA and the Gen-Probe PACE 2 assay are comparable to but significantly less sensitive than culture. Use of a grey zone may help identify the need for repeat or confirmatory testing.

Markers of human immunodeficiency virus infection in pediatric bronchoalveolar lavage samples.

Pulmonary cells and fluid obtained by bronchoalveolar lavage (BAL) from 19 pediatric acquired immunodeficiency syndrome (AIDS) patients with pneumonia were examined for markers of human immunodeficiency virus (HIV-1) infection. The HIV-1 DNA was detected in BAL cells by polymerase chain reaction (PCR) in 14 of 15 patients (93.3 percent). Immunostaining of cytocentrifuged cell preparations of six specimens revealed that HIV-1 antigen was associated with from five percent to 95 percent of the alveolar macrophages. Analysis of the 22 cell-free BAL fluids by enzyme immunoassay (EIA) showed that samples from three patients (15.8 percent) contained HIV-1 p24 antigen. One sample, with a dilution factor of 15.1 relative to serum, contained a markedly elevated antigen concentration (106 pg per ml) compared to the serum concentration (41.6 pg per ml). Antibodies to HIV-1 were present in the BAL fluids of six patients (31.6 percent) at levels detectable by EIA. By Western blot analysis, three samples yielded more intense gp120 bands compared to bands observed with matched serum samples. Our results suggest that HIV-1 and antibodies to this virus are frequently present in the lungs of children with AIDS and that the serum antigen and antibody profile of some patients does not reflect local pulmonary levels.

Differential recovery of cytomegalovirus from cellular and supernatant components of bronchoalveolar lavage specimens.

The recovery of cytomegalovirus from bronchoalveolar lavage (BAL) specimens was compared after inoculation of MRC-5 tube and shell vial cell cultures with four different BAL preparations. Analysis of culture results obtained with 55 cytomegalovirus culture-positive samples showed significant differences in the ability to isolate virus from the supernatant and cellular components of these specimens. There was a 52% reduction in cytomegalovirus recovery and a significant delay in the development of cytopathic effect in cultures inoculated with the cellular component of BAL specimens when compared to cultures inoculated with crude BAL cells and fluid. The mean time for detection of cytopathic effect was 11.8 days in tubes inoculated with crude BAL and 18.2 days for tubes inoculated with BAL cells. A similar effect was observed using a rapid shell vial culture technique. A 39% reduction in the number of isolates and a 57% reduction in the number of positive cells were observed in vials inoculated with cells when compared to cultures inoculated with crude BAL. By contrast, using cell-free BAL supernatant as inoculum did not reduce the number of positive cultures or delay development of cytopathic effect. The results suggest that in most BAL specimens, cytomegalovirus is associated with the cell-free, rather than the cellular, component. Although BAL cell concentrates frequently are used for cultivation of viruses from BAL, our results showed that the use of these preparations results in a significant number of false-negative cytomegalovirus cultures.

Characterization of cells, immunoglobulins, and immune complexes present in the bronchoalveolar lavage of pediatric AIDS patients.

The role of local immunity in relation to the frequent and heterogeneous pulmonary manifestations of HIV-1 infection in children is poorly understood. In order to examine lung immunity in pediatric AIDS patients, the cellular composition, immunoglobulin, and immune complex (IC) levels were evaluated in 23 samples of bronchoalveolar lavage (BAL) fluid and peripheral blood from 19 pediatric AIDS patients with acute pulmonary pathology. The patients were of two age groups: 4.0-21.5 months (N = 9) and 2.3-13.1 years (N = 10). In BAL, lymphocytes were elevated in 25-45% of samples, and neutrophils were elevated in 27-33%; BAL macrophages varied in percentage (28-99%) but had normal morphology. The blood differentials of pediatric AIDS patients undergoing BAL did not show significant differences when compared with a group of pediatric patients with tuberculosis, but leuko- and neutropenia was noted when compared with pediatric patients with pneumonia and no HIV disease. Of the immunoglobulins measured (IgG, IgM, IgA) only IgG was detectable in unconcentrated BAL fluid (1-37 mg/dl, equivalent to 12-630 mg/dl in the epithelial lining fluid after correction using urea as a marker of dilution). All patients were hypergammaglobulinemic and 83% had high levels of circulating IC (2-40 muEq/ml). Six BAL specimens (26%) also contained IC. The estimated level of IC in lung epithelial lining fluid (after correcting for dilution) was up to fivefold higher than IC concentration in corresponding sera. Specific antibodies to HIV-1 were demonstrated in 35% of the BAL samples by ELISA and in 65% by Western blotting.(ABSTRACT TRUNCATED AT 250 WORDS)

The relationship of symptoms to performance in paced patients with breathlessness.

Eighteen adult patients presenting with breathlessness associated with bradycardia, and whose breathlessness was diminished or abolished by permanent pacing, were studied at least one month after this procedure in order to examine the relationship between symptoms and exercise performance. All were pacing-dependent at rest and were studied over successive two-weekly periods at set rates of 50, 70 and 90 beats min-1 in a double-blind, balanced and randomized trial. The degree of breathlessness was closely related to exercise capacity judged by 6-min walk testing, effort scores and weekly pedometer distance. Overall results were worse at 50 beats min-1 than the two faster rates. For a given individual, changing of ventricular rate caused parallel alterations in symptoms and performance. The 6-min walking test was a useful guide to disability in these patients, tightly linked to the symptoms of effort and breathlessness, and may be of clinical value in assessing mild heart failure. The pedometer readings were influenced more by the patients' walking habits than by fitness.

Fundamental differences between the standard 12-lead electrocardiograph and the modified (Mason-Likar) exercise lead system.

A comparison of the standard 12-lead electrocardiograph with the Mason-Likar lead system widely used for exercise stress testing shows that the two are not 'essentially identical' as was originally claimed. Placement of the limb electrodes onto the torso distorts the electrocardiograph causing a rightward shift of the mean QRS axis, a significant reduction in R-wave amplitude in leads I and aVL, and a significant increase in R-wave amplitude in leads II, III and aVF; the R-wave amplitude of the chest leads is also altered. The so-called 'inferior' leads on the exercise electrocardiography are probably modified anterior/inferior leads, since their R-wave amplitudes correlate closely with those of antero-lateral chest leads. The inferior surface of the heart is not represented in isolation on the exercise electrocardiograph, thus explaining the reported inability of the exercise test to predict the location of coronary artery disease and high incidence of false negative tests in patients with ischaemia limited to the inferior cardiac surface.

Dependency of the elderly in a rural population.

Fifty-five elderly people living in a small village were interviewed to discover the level of need for medical and social services and to establish the level of provision to meet that need. Contrary to expectations there was little perceived need and hence minimal contact with statutory services. This emphasizes the importance of adequate assessment of need before providing expensive social and rehabilitation services.

Pacing failure due to flecainide acetate.

Flecainide acetate is a recently introduced, class 1 antiarrhythmic agent that is highly effective in the treatment of ventricular and atrioventricular/nodal reentrant tachycardias. Although both intravenous and orally administered flecainide are known to cause an increase in the pacing threshold, an abrupt and potentially lethal rise in threshold causing failure of a properly functioning, newly implanted pacing system has not to our knowledge been described. We report such a case to stress the need for caution when using this drug in elderly pacemaker patients.

Endocardial pacing electrode design and rate of displacement.

In a series of 184 patients with a permanent endocardial pacing system the rate of electrode displacement was 3-0 per cent using the Devices L120SR electrode, and 23-1 per cent using the Devices S120 electrode. The technique and pacing team were unchanged during the period of study. It is suggested that the design and mechanical characteristics of the elctrodes were responsible.