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Biomedical subjects

B F Polk

Publications and source records attributed to B F Polk.

At least 37 records · Page 2Linked to original sources
PubMed1989

Ocular manifestations of acquired immune deficiency syndrome.

The ocular complications of acquired immune deficiency syndrome (AIDS) include: (1) a noninfectious microangiopathy, most often seen in the retina, consisting of cotton-wool spots with or without intraretinal hemorrhages and other microvascular abnormalities; (2) opportunistic ocular infections, primarily cytomegalovirus (CMV) retinitis; (3) conjunctival, eyelid, or orbital involvement by those neoplasms seen in patients with AIDS (i.e., Kaposi's sarcoma and lymphoma); and (4) neuro-ophthalmic lesions. In a series of 200 AIDS patients evaluated clinically, AIDS retinopathy was present in 66.5%. Sixty-four percent had cotton-wool spots, and 12% had intraretinal hemorrhages. Cytomegalovirus retinitis was diagnosed in 28% of AIDS patients. Neuro-ophthalmic lesions were found in 8% of all AIDS patients and were present in 33% of those patients with cryptococcal meningitis. Acquired immune deficiency syndrome retinopathy was present in 40% of 35 patients with the AIDS-related complex (ARC) and in 1.3% of 232 patients with asymptomatic human immunodeficiency virus (HIV) infection, evaluated photographically. These results suggest that the prevalence of AIDS retinopathy increases with increasing severity of HIV infection, and that CMV retinitis presents a significant vision-threatening problem in AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Prevention of catheter-associated urinary tract infection: a cost-benefit analysis.

A cost-benefit analysis was used to assess four strategies to prevent catheter-associated urinary tract infections in an acute care setting. Routine use of catheters with sealed collection junctions, selective use of these catheters, and oral antibiotic prophylaxis all result in fewer deaths, fewer infections, and lower overall costs than not using any of these. Routine use of sealed junction catheters results in fewer infections and deaths than does selective use. When the cost of a nosocomial urinary tract infection is +500, routine use of sealed junction catheters is also less expensive than selective use in many circumstances. Oral antibiotic prophylaxis would result in the lowest net cost and the fewest deaths and infections, if it were as effective as parenteral prophylaxis, if more than 72% of patients received it, and if important negative factors such as selection of antimicrobial resistance and adverse drug reactions are not considered. When there is no extra cost of sealed junction catheters, their use is less expensive than the oral prophylaxis strategy if the total cost of oral prophylaxis, including the cost of adverse reactions, is greater than +15. If the extra cost of sealed junction catheters is +4 per unit, their use is less expensive than oral prophylaxis when its cost exceeds +35. Prevention of catheter-associated urinary tract infection reduces the overall cost of patient care, even when the prevention itself incurs costs. This analysis supports the routine use of sealed junction catheters in most acute care situations that require indwelling catheter drainage. Currently, we do not recommend routine antibiotic prophylaxis.

Catheters, Indwelling↗
PubMed1989

Acquired immunodeficiency syndrome (AIDS)-free time after human immunodeficiency virus type 1 (HIV-1) seroconversion in homosexual men. Multicenter AIDS Cohort Study Group.

To estimate the time interval between human immunodeficiency virus type 1 (HIV-1) seroconversion and acquired immunodeficiency syndrome (AIDS) diagnosis in homosexual men, prospective incident cohorts are difficult to obtain and, if assembled, provide few events owing to the long incubation time. Although seroprevalent cohorts are numerous in size and events, the information is limited due to the unknown times since seroconversion. To combine the information provided by 1,628 seroprevalent men (304 AIDS cases) and 233 seroconverters (12 AIDS cases) being followed in a multicenter study since 1984, the postseroconversion changes in hematologic variables occurring in the incident cohort were used to develop a model that allowed for the imputation of the unknown times since seroconversion for the seroprevalent cohort. Nonparametric life table methods incorporating truncation and censoring were applied for the estimation of the probability distribution of the AIDS-free time after seroconversion. The precision of the estimates was evaluated using bootstrap methods. The analysis suggested that AIDS is unlikely (less than 0.5%) in the first year; 78% of seropositive homosexual men remain AIDS-free 60 months after seroconversion; and the AIDS incidence increases for months 12-36 and levels off at 38 per 1,000 person-semesters for months 42-60. The nonparametric estimate of the incidence rate suggests a median AIDS-free time of 11 years, which is longer than previous estimates based on parametric models.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Performance of serological assays for early detection of human immunodeficiency virus type 1 seroconversion.

Early detection of sexually transmitted human immunodeficiency virus type 1 (HIV-1) infection was investigated in newly infected persons to determine the sensitivities of currently available serologic techniques. Serial serum samples were obtained from 51 newly infected persons in a cohort of 1,153 homosexual or bisexual men participating in the Baltimore Center of the Multi-Center AIDS Cohort Study during the first 2.5 years of follow-up. Of 51 participants, 45 seroconverted between any two seminannual visits and 6 were found to have been infected just prior to study entry. Five enzyme-linked immunosorbent assays (ELISAs), two immunoblots, and an HIV-1 P24 antigen capture assay were performed on a panel of all serial serum samples from these individuals. The sensitivity of ELISAs varied between 50 and 84% in seroconverters with less-developed antibody response. In this group of seroconverters, the most sensitive antibody assay was an immunoblot from Biotech (95%) and HIV-1 P24 was found infrequently (9.5%). The sensitivities of ELISAs and immunoblot were 100% in individuals with more-developed antibody patterns, and no HIV-1 P24 was detected among them.

AIDS Serodiagnosis↗
PubMed1989

Temporal trends of human immunodeficiency virus type 1 (HIV-1) infection among inmates entering a statewide prison system, 1985-1987.

Acquired immune deficiency syndrome (AIDS) became the leading cause of death among Maryland State prisoners in 1985. To identify the prevalence, risk factors, and temporal trends for infection with the human immunodeficiency virus type 1 (HIV-1) in the statewide prison system, excess sera were obtained from incoming male inmates during specified periods between April and June 1985, 1986, and 1987. Correctional medical personnel also provided demographic variables of age, race, offense category, sentence, jurisidiction, and an indicator of intravenous drug use. Once rendered anonymous, specimens were assayed for antibody to HIV-1, using ELISA and Western blot techniques. For data from April to June 1985, 1986, and 1987, the crude prevalence of anti-HIV-1 was 7.1, 7.7, and 7.0%, respectively. Although one-third of incoming inmates were identified as intravenous drug users (IVDUs), the drug use variable was missing for 70% of the 1985 sample, and 40% of the 1986 sample. Several strategies were used to examined temporal trends in the context of missing data. Univariate analyses suggested no substantial change over time for either HIV-1 seroprevalence or risk of infection among IVDUs.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMed1988

The influence of human immunodeficiency virus (HIV) infection on antibody responses to influenza vaccines.

STUDY OBJECTIVE: To ascertain whether subjects infected with human immunodeficiency virus (HIV) generally develop protective hemagglutination inhibition antibody responses to inactivated influenza vaccines. DESIGN: Prospective study of 104 persons before and after immunization. SETTING: Outpatient clinic and hospital ward. PATIENTS: Persons with the acquired immunodeficiency syndrome (AIDS) (n = 25), AIDS-related complex (n = 14), and HIV-seropositive men with only lymphadenopathy or no symptoms (n = 27). Controls were HIV-seronegative homosexual men (n = 22) and HIV-seronegative heterosexuals (n = 16). INTERVENTIONS: Subjects were immunized with inactivated vaccines containing 15 micrograms of each of the following influenza virus hemagglutinins: A/Taiwan/1/86 (HINI), A/Mississippi/1/85 (H3N2), A/Chile/1/83 (HINI), and B/Ann Arbor/1/86. MEASUREMENTS AND MAIN RESULTS: Fourfold or greater antibody responses occurred less frequently in subjects with HIV infections than in HIV-seronegative controls. Protective levels (1:64 or greater) of hemagglutination inhibition antibodies were attained by 94% to 100% of HIV-seronegative controls, 52% to 89% of HIV-seropositive asymptomatic subjects, and 13% to 50% of subjects with AIDS or AIDS-related complex. No increase in the prevalence or level of serum HIV p24 antigen or clinical deterioration was detected among HIV-infected persons after influenza immunization. CONCLUSIONS: Because of the poor antibody responses to influenza vaccines among HIV-infected subjects, even in many with no or minimal symptoms, alternative strategies for preventing influenza, such as booster doses of influenza vaccine, prophylaxis with amantidine, or both should be considered.

AIDS-Related Complex↗
PubMed1988

Cerebrospinal fluid abnormalities in homosexual men with and without neuropsychiatric findings.

We have studied cerebrospinal fluid obtained from 38 homosexual or bisexual men participating in a prospective study of the neuropsychological disorders associated with human immunodeficiency virus (HIV) infection. Twenty-two subjects had neuropsychiatric findings and seropositivity, 11 asymptomatic subjects had seroconverted within 6 to 24 months, and 5 subjects were seronegative controls. Only 1 had acquired immunodeficiency syndrome-related complex, and none had the acquired immunodeficiency syndrome when initially studied. There was a high rate of cerebrospinal fluid abnormalities in men with neuropsychiatric findings, including pleocytosis (41%), elevated IgG and IgG index (47%), and oligoclonal bands (18%). Even in the absence of neuropsychiatric findings, the asymptomatic HIV-seropositive subjects frequently had spinal fluid abnormalities. Of those with neuropsychiatric findings, HIV p24 antigen was detectable in cerebrospinal fluid in only 1 individual, yet HIV was isolated in 11 of 16 (69%) compared to 2 of 7 (29%) of those without neuropsychiatric findings. The identification of cerebrospinal fluid abnormalities in individuals known to have become infected within 6 to 24 months supports the hypothesis that the nervous system is an early target for HIV.

Adolescent↗
PubMed1988

Endocrine disorders in men infected with human immunodeficiency virus.

Gonadal, adrenal, and thyroid functions were evaluated in 70 men seropositive for human immunodeficiency virus (HIV) infection, clinically categorized as asymptomatic (n = 19), AIDS-related complex (ARC) (n = 9), or acquired immunodeficiency syndrome (AIDS) (n = 42). Twenty of 40 men (50 percent) with AIDS were hypogonadal. Mean serum testosterone concentrations in both ARC (292 +/- 70 ng/dl) and AIDS (401 +/- 30 ng/dl) men were significantly less than in asymptomatic (567 +/- 49 ng/dl) or normal men (608 +/- 121 ng/dl). Of these hypogonadal men, 18 of 24 (75 percent) had hypogonadotropic hypogonadism. Seven of eight hypogonadal men (88 percent) had a normal gonadotropin response to gonadotropin-releasing hormone administration. Hypogonadism correlated with lymphocyte depletion and weight loss. Adrenal cortisol reserve, evaluated by adrenocorticotropin stimulation, was normal in 36 of 39 patients (92 percent) with AIDS. Indices of thyroid function were normal with the exception of one ARC man with a low free thyroxine index. In conclusion, hypogonadism is common in men with HIV infection and may be the first or most sensitive endocrine abnormality.

AIDS-Related Complex↗
PubMed1988

Prevalence of enteric pathogens in homosexual men with and without acquired immunodeficiency syndrome.

We studied 388 homosexual or bisexual men from the Baltimore-Washington area to define the spectrum of enteric pathogen carriage in a population at high risk for "gay bowel syndrome" in association with human immunodeficiency virus infection. Seventy-seven patients with acquired immunodeficiency syndrome, 68 gay men with symptoms of acute diarrhea or proctitis, and 243 gay men without gastrointestinal symptoms and participating in a natural history study of human immunodeficiency virus infection were selected for study. Approximately 12% of the asymptomatic men harbored at least one enteric pathogen; the most frequently recovered were Chlamydia trachomatis, herpes simplex virus, and Giardia lamblia. Men carrying a pathogen were more likely to be human immunodeficiency virus seropositive (48%) than men without a pathogen (25%) (p = 0.018), more likely to have fewer T helper cells (p = 0.015), and more likely to have a mucopurulent exudate (p = 0.014). We recovered an agent of enteric disease from 68% of gay men presenting with diarrhea or proctitis. Campylobacter species, herpes simplex virus, Neisseria gonorrhoeae, C. trachomatis, G. lamblia, and Shigella species were identified most frequently. The most common pathogen associated with diarrhea in acquired immunodeficiency syndrome was Cryptosporidium (16% of 49 cases). Other agents identified were Clostridium difficile, Vibrio parahemolyticus, Campylobacter species, G. lamblia, Isospora, and cytomegalovirus. Approximately half of the identifiable etiologic agents of diarrhea in acquired immunodeficiency syndrome patients were treatable with antibiotics, but these agents required special culture procedures for detection.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Flow cytometric quantitation of T cell phenotypes in cerebrospinal fluid and peripheral blood of homosexual men with and without antibodies to human immunodeficiency virus, type I.

Two-color flow cytometry was used to analyze T cell subsets (total (CD3), helper-inducer (CD4), and suppressor-cytotoxic (CD8] in paired specimens of cerebrospinal fluid (CSF) and peripheral blood of 66 homosexual men, including 62 with antibodies to human immunodeficiency virus, type 1 (HIV-1). With the exception of one traumatic specimen, all of the CSF specimens, 52 of which had less than or equal to 5 lymphocytes/mm3, were evaluated fully, with the number of lymphocytes counted for each antibody ranging from 200 to 2933 (mean = 1129). Proportions of CD3, CD4, and CD8 lymphocytes in CSF were very highly correlated with the proportions of these cells in the peripheral blood (r = 0.87, 0.96, and 0.94, respectively), as was the CD4/CD8 ratio (r = 0.98). These strong correlations were present in each of seven subgroups of study subjects defined on the basis of detailed neurologic examination, neuropsychological testing, and the presence or absence of antibodies to HIV-1. In the population studied, T cell phenotypes in CSF as analyzed by two-color flow cytometry were largely determined by the corresponding proportions in the peripheral blood.

Adult↗
PubMed1988

Reproducibility of the diagnosis of cervicitis in pregnancy.

Cervicitis has been associated with several infections of the female genital tract. Criteria have been established for making the diagnosis of cervicitis in gynecologic populations but there are no well-established criteria for diagnosing cervicitis in obstetrical populations. Because of the association of the cervicitis and sexually transmitted diseases, and because of the association of sexually transmitted diseases and adverse pregnancy outcome, the present study was undertaken in an attempt to establish criteria for the diagnosis of cervicitis in pregnancy. We also attempted to determine the reproducibility of that diagnosis with respect to intra- and interobserver variability. We concluded that intraobserver variability is improved after specific training has been completed and that interobserver variability may be reduced to an acceptable level. On a public health scale, this may allow for identification of a population at high risk for adverse pregnancy outcome when sophisticated microbiologic techniques are unavailable.

Adolescent↗
PubMed1988

Immunogenicity and safety of measles vaccine in ill African children.

A concurrent prospective study was conducted in Rwanda to compare the immunogenicity and safety of live, attenuated measles vaccine in ill and well children. Five hundred and eighteen children aged 8 to 19 months were selected from children attending the acute care and immunization services of two clinics. Two hundred and sixty-seven ill children and 251 well children were enrolled and examined. Serological tests were performed on blood samples obtained before and 40 days after measles immunization. Among the 208 ill children and 215 well children who were seronegative at baseline and had unequivocal follow-up serological results, seroconversion rates were 81% and 80%, respectively. Side effects were modest and were equally frequent in the two study groups (15.4% among ill children versus 15.1% among well children). These results support a change in measles immunization policy in developing countries with respect to immunization of children with acute illnesses. Such a change would make a great contribution to decreasing the enormous burden of measles in the developing world through increased immunization coverage.

Antibodies, Viral↗
PubMed1988

Transmission of HIV-1 within a statewide prison system.

To assess the incidence of infection with HIV-1 in the Maryland state prison system, inmates with excess sera stored from specified intake periods between April and June 1985 and 1986 were approached in May 1987 to volunteer for venipuncture. Of the 2286 inmates for whom intake specimens were stored, 1038 (45.4%) no longer incarcerated as of April 1987 were excluded from the study; another 319 missed the survey. Of the 929 eligible inmates approached for the study, 446 (48%) consented and 422 (94.6%) provided a specimen. Twenty-nine (6.6%) were confirmed seropositive at time of entry into prison, indicating that infection had occurred prior to incarceration. Baseline seropositives were more likely (P less than 0.05) to be non-violent offenders, committed in Baltimore City, and black. The 393 participants seronegative at baseline provided a total of 482 prison-years of potential exposure to infection. Two inmates seroconverted with baseline specimens seronegative on Western blot and follow-up sera confirmed positive; their duration of pre-incarceration detention was 69 and 146 days, respectively. No interruption of incarceration was recorded for these two inmates. The rate of infection in this prison sample, which does not include an average of 2 months of pre-incarceration detention for the study sample, was 0.41% per prison-year.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Response of preterm infants to diphtheria-tetanus-pertussis vaccine.

The American Academy of Pediatrics recommendation that immunization of preterm infants with diphtheria-tetanus-pertussis (DTP) vaccine should begin at 2 months after birth, regardless of gestational age, is based on limited data. A prospective study was conducted to determine the immunogenicity and safety of DTP vaccine in preterm infants. One hundred ten preterm and 146 full term infants received doses of DTP at 2, 4 and 6 months after birth. Adjusted analysis of the antibody responses indicated that after three doses mean titers among preterm infants to each vaccine component were comparable to those of full term infants. Adjusted analysis of the incidence of adverse events indicated that the risk of adverse events in preterm infants was not significantly higher than that in full term infants. DTP vaccine is immunogenic and safe in preterm infants when the series is initiated at 2 months after birth, and this study supports the current recommendation of the American Academy of Pediatrics.

Antibody Formation↗
PubMed1988

Plasma and tissue concentrations of ceforanide and cefazolin in women undergoing hysterectomy.

Thirty-four women who underwent vaginal hysterectomy received either ceforanide or cefazolin as perioperative antimicrobial prophylaxis. Samples of plasma, myometrium, endometrium and fallopian tubes were obtained at various intervals after injection and were assayed for cephalosporin concentration. Following intramuscular injection approximately 1 h prior to surgery, both drugs provided adequate tissue levels at the time of the procedure. Although both antimicrobials achieved similar tissue concentrations, all tissue samples for ceforanide exceeded the MIC90 for Escherichia coli while in the cefazolin group 9/18 myometrial samples and 10/15 endometrial samples fell below the MIC90 for this organism.

Adult↗
PubMed1988

Loss of human immunodeficiency virus type 1 (HIV-1) antibodies with evidence of viral infection in asymptomatic homosexual men. A report from the Multicenter AIDS Cohort Study.

Four asymptomatic homosexual men reverted from positive to negative serologic results for the human immunodeficiency virus, type 1 (HIV-1) over 2.5 years, as shown by enzyme-linked immunosorbent assay (ELISA) and Western blot. Antibody bands in the Western blot from three men were undetectable 6 to 12 months after being positive; gradual fading of the number and intensity of bands was seen in the other man. No HIV-1-p24 antigenemia was detected; cryopreserved peripheral blood mononuclear cells were negative for HIV-1 by standard culture assay. Polymerase chain reaction (gene amplification) assays were done on peripheral blood mononuclear cells and showed the HIV-1 provirus in all subjects 6 to 18 months after the last positive antibody test. Serum specimens from each participant were genetically identical. Polymerase chain reaction showed that peripheral blood mononuclear cells from one subject at different times matched by HLA DNA typing. Clinical and laboratory features of these four men were similar to those of other seronegative subjects. Rare, asymptomatic persons seropositive for HIV-1 may not remain seropositive, but may remain latently infected with HIV-1.

Adult↗