Adenosine deaminase and interferon gamma measurements for the diagnosis of tuberculous pleurisy: a meta-analysis

OBJECTIVE

As Mycobacterium tuberculosis isolation rates in tuberculous effusions are relatively low, several biochemical and immunological markers have been proposed to diagnose tuberculous pleurisy including adenosine deaminase (ADA) and interferon-gamma (IFN-gamma). Here we summarise the literature on ADA and IFN-gamma as predictors of tuberculous pleurisy.

METHODS

After a systematic review of English language studies, we used summary receiver operating characteristic curve (SROC) analysis to determine the cumulative diagnostic accuracy of both markers and Bayes' theorem to calculate post-test probability of disease in settings with different prevalences of tuberculous pleurisy, assessed and reported the quality of primary studies.

RESULTS

From 1978 to November 2000, studies containing sufficient data for the determination of both sensitivity and specificity were 31 on ADA, including 4738 patients, and 13 on IFN-gamma, including 1189 patients. SROC curve yielded a maximum joint sensitivity and specificity of 93% for ADA and 96% for IFN-gamma. In the setting of tuberculous effusion prevalence of 5%, 25% and 85%, post-test probability of a negative ADA test were 0.4%, 2.4% and 24%, and 0.22%, 1.2% and 17% for a negative IFN-gamma test.

CONCLUSION

With the caveat that limitations in the design of the studies summarised here may distort estimates of test performance, ADA and IFN-gamma appear to be reasonably accurate at detecting TB pleurisy.

Radiological patterns in HIV-associated pulmonary tuberculosis: comparison between HAART-treated and non-HAART-treated patients

AIM

To evaluate whether highly active antiretroviral therapy (HAART) modifies radiographic appearances of pulmonary tuberculosis (TB), in terms of patterns and their relative frequencies, among patients with human immunodeficiency virus (HIV) infection.

MATERIALS AND METHODS

Chest radiographs were obtained in 209 HIV-infected patients with culture confirmed pulmonary TB. Computed tomography (CT) images were also reviewed for 42 patients whose chest radiographs were normal or showed questionable abnormalities. Imaging was evaluated for the presence and distribution of consolidation, cavitation, interstitial changes, pleural disease, adenopathy, and were classified as a primary or post-primary pattern.

RESULTS

A post-primary pattern was more frequent after 1996 when HAART came into clinical use. Forty-four percent (77/176) of patients not on HAART had a post-primary pattern in comparison with 82% (27/33) of patients receiving HAART (p<0.001). A primary pattern was significantly more frequent (p<0.001), in patients with more severe immunosuppression (CD4 lymphocyte less than 200/mm(3)).

CONCLUSION

HIV patients receiving HAART with pulmonary TB, had a post-primary pattern more frequently than those not receiving this treatment. This observation is consistent with the partial restoration of cell-mediated immunity that can be induced by HAART.

[Cervico-vaginal infections. Study of a population in the Turin area]

BACKGROUND

Aim of this study is to determine the prevalence, in the Turin area, of the pathogens chiefly involved in the genesis of the most common infections of the female genitalia.

METHODS

This is a retrospective study. During the period of time beginning from January 1, 1997 and ending December 31, 1999, we examined 10,249 women from 14 years to 54 years of age, who were seen at the out-patient diagnosis service of the Sant'Anna Hospital. The patients' cervical specimens were screened for common germs, Candida spp., Trichomonas vaginalis, Bact. Vaginosis, Chlamydia trachomatis, Microplasms, and Neisseria gonorrhea. The prevalence of each micro-organism was found. The obtained data were cross-referenced with the risk factors in the clinical history of each patient. The chi(2) test with a C.I. of 95% was used for the statistical evaluations.

RESULTS

It is shown by a detailed analysis of the data in our possession that an anamnesis oriented mainly for the evaluation of the various risk factors would be more effective than one oriented for the presence of a subjective symptomatology, since many of these infections are either weakly symptomatic or totally asymptomatic (especially in the case of C. trachomatis), as has been many times underlined in the international literature.

CONCLUSIONS

Greater attention should be given to the collection of anamnestic information in order to more precisely target for examination those subjects at greater risk of contracting a sexually transmitted infection.

Pulmonary tuberculosis in HIV-infected patients presenting with normal chest radiograph and negative sputum smear

BACKGROUND

HIV-infected patients with pulmonary tuberculosis exhibit atypical radiological presentation and negative sputum smear more frequently than their HIV-negative counterparts.

PATIENTS AND METHODS

We performed a retrospective study based on a chart review of 146 HIV-infected patients with pulmonary symptoms and culture-proven pulmonary tuberculosis. We compared clinical characteristics and the outcome in 71 patients (49%) with positive sputum smear (SS+), 62 patients (42%) with negative sputum smear/abnormal chest X-ray (SS-/CXR+) and 13 patients (9%) with negative sputum smear/normal chest X-ray (SS-/CXR-). Patients were enrolled from January 1987 to December 1998, and were followed up until December 1999.

RESULTS

On hospital admission the three groups of patients examined did not differ significantly in demographic characteristics, degree of immunosuppression or Mycobacterium tuberculosis drug-susceptibility pattern. SS-/CXR- patients were significantly Less LikeLy to present with prolonged fever and dyspnea. Median survival was shorter for SS-/CXR- patients (6.4 months vs 20.2 and 18.8 months in the other two groups). In multivariate analysis, SS-/CXR-patients had a significantly increased risk of death (hazard ratio 3.0, 95% confidence interval, 1.4 to 6.4, p = 0.004) compared to SS+ patients. This increase in risk was no longer statistically significant when initiation of antituberculous therapy within 8 weeks from the collection date of the first specimen yielding M. tuberculosis was included in the multivariate model.

CONCLUSION

Decreased survival was observed in HIV-infected patients with pulmonary tuberculosis and with both negative sputum smear and normaL chest X-ray presentation. This may primarily be a resuLt of delayed tuberculosis diagnosis and initiation of antituberculous therapy. The latter delay may also lead to a faster progression of HIV infection in SS-/CXR patients, in whom diagnostic oversight may be common.

Changing patterns of "hospital-at-home" care use by persons with AIDS in the era of combination antiretroviral therapy

This study describes how hospital-at-home care (HHC) use by persons with acquired immune deficiency syndrome (PWA) has changed since the introduction of combination antiretroviral therapy (ART). For this study, all adult PWA (877) admitted for the first time to the HHC program, established for PWAs in the metropolitan area of Rome, between January 1994 and December 1998, were enrolled. Temporal changes in sociodemographic and clinical characteristics were evaluated. For subjects who concluded their first HHC cycle (851/877), the reasons for ending the service were assessed over time. From 1994 to 1998, the proportion of patients admitted to HHC of those living with AIDS in the Rome area decreased significantly (from 15.1% to 7.5%), while the median CD4+ cell count at HHC entry increased significantly. The proportion of patients referred to outpatient services at the end of their cycle of HHC increased sevenfold from 1994 to 1998, with a steep increase between 1996 and 1997. In multivariate analysis, only the use of triple-combination ART was significantly associated with referral to outpatient care (odds ratio [OR] = 4.26; 95%, confidence interval [CI] = 1.94-9.34). The results suggest that HHC use by PWAs in the ART era has diminished, while the HHC use pattern has also changed: there is a growing tendency to provide care to patients with less advanced human immunodeficiency virus (HIV) disease, prior to the beneficial effects of drugs, and the consequent referral to outpatient care.

The changing picture of the HIV/AIDS epidemic

Twenty years after it was first recognized, the HIV/AIDS epidemic continues to expand, but its impact varies greatly in different parts of the World. The worst of the epidemic is now centered in developing countries, especially sub-Saharan Africa, and areas such as Eastern Europe, which was only marginally involved a few years ago but has recently experienced the largest growth in the epidemic. In industrialized countries Highly Active Antiretroviral Therapy (HAART) has changed the natural history of HIV/AIDS, causing a reduction in mortality and morbidity due to HIV/AIDS and related diseases. Many interlocking factors determine the impact of HAART at the population level, including reduction of morbidity and mortality, changes in the natural history of HIV/AIDS and associated illnesses, and the effects of HAART on HIV transmission. To fully appreciate the potential benefits of HAART, the epidemic should continue to be monitored in the future, and the effects of HAART on reducing HIV transmission should also be evaluated. Interventions addressed to encourage the adoption of safer sex practices are badly needed, since a "rebound" in risky sexual behaviors was recently reported among high risk groups, which is, at least in part, attributable to the optimism about new treatments.

Female sex and the use of anti-allergic agents increase the risk of developing cutaneous rash associated with nevirapine therapy

To identify factors associated with cutaneous rash, we performed a retrospective multicentre analysis of HIV outpatients starting a highly active antiretroviral therapy regimen containing nevirapine. A total of 62 cutaneous adverse events were observed in 429 patients. Rash hazard was increased in women, by the prophylactic use of glucocorticoids or antihistaminics, and was reduced by escalating the initial dose of nevirapine. Women receiving glucocorticoids had a 3 month cumulative probability of rash of 0.41.

Guidelines of tuberculosis preventive therapy for HIV-infected persons: a prospective, multicentre study. GISTA (Gruppo Italiano di Studio Tubercolosi e AIDS)

The aim of this study was to assess the degree of implementation of national guidelines for isoniazid preventive therapy (IPT) among human immunodeficiency virus (HIV)-infected individuals and factors affecting the impact of the programme. Twenty-eight infectious disease hospital units in Italy participated in this observational, multicentre, prospective cohort study. A number of HIV-infected subjects, (n=1,705) seen for the first time as outpatients, were included in this analysis. Of the subjects considered, 1,215 out of the 1,705 completed purified protein derivative (PPD) screening. Variables independently associated with offering and completion of PPD screening included having acquired immune deficiency syndrome (AIDS), higher educational levels and currently receiving therapy. Overall, 103 subjects were identified as candidates for IPT. Of these subjects, five had tuberculosis and 15 had contraindications to IPT. Forty subjects agreed to start IPT, and 29 completed a full-course regimen. The incidence of tuberculosis among IPT candidates who either did not begin or discontinued IPT was 6.1 per 100 person-yrs, while no cases of tuberculosis were observed in subjects completing IPT. Several factors may limit the implementation of an isoniazid preventive therapy programme for human immunodeficiency virus-infected persons. Physicians fail to offer purified protein derivative screening to patients with high degrees of immunodeficiency, and those with a more intense workload seem to pay less attention to this test. The high number of contraindications among patients and their low level of acceptance further affects the impact of isoniazid preventive therapy.

Determinants of emerging and re-emerging infectious diseases

In the 1960s and 1970s, many public health experts assumed that infectious diseases could at long last be conquered as had occurred with smallpox. In the last two decades, reports warned that infectious diseases were clearly not a problem of the past. They could not be considered as a unique or isolated event of wild and faraway regions, but penetrated every corner of the globe. Emerging infectious diseases have been recently described as clinically distinct conditions whose incidence in humans has increased regionally or worldwide within the past two decades. Emergence may be due to the introduction of new agents to or the recognition of an existing disease that has gone undetected, and re-emergence may describe the re-appearance of known diseases after a decline in incidence. In this article a global, multidisciplinary and integrated approach in different fields of demography, epidemiology, economy, ecology, anthropology and environment at science has been considered to describe the different determinants responsible for the emergence and re-emergence of infectious diseases.

Hospital care for patients with AIDS at "Lazzaro Spallanzani" Institute in the last decade

We reviewed data on hospital care of HIV/AIDS patients at Lazzaro Spallazani Institute between 1991 and 1999. The number of newly diagnosed AIDS cases increased until 1995 and decreased constantly thereafter. The proportion of AIDS cases diagnosed at our institution over the total number of cases reported in our region and in our country increased from 31.2 to 59.8% and from 3.9 to 8.7% respectively (p<0.001). In the entire study period, 10044 out of 18,434 (54.5%) of patients admitted to acute care wards were diagnosed with HIV related pathologies. The number of admission of HIV/AIDS patients to acute-care wards increased until 1995 and remained constant thereafter. Our data suggest that a consistent need for inpatient hospital care remains even in the era of HAART.

AIDS prevention campaigns: what lessons can be learned?

The purpose of this article is to examine preventive programs which may help to reduce the rising number of HIV infected individuals. Behavioral theories were taken into consideration from which stimulate behavioral changes. To measure the effectiveness of the behavioral theories, different evaluation methods were analysed. Following the recommendations made by Choi and Coates, new guidelines on which to base preventive AIDS compaigns in the future have been set out.

Impact factor in AIDS and other infectious diseases

The impact factor (IF) is the most accurate system currently available for objectively evaluating the scientific productivity of individual researchers and institutions. It represents the quality level of a periodical and, at the same time, is a convenient reference parameter for the researcher to use in choosing an appropriate journal before submitting his own work for consideration. From this standpoint, we conducted an analysis of periodicals with the highest IF, including those strictly related to infectious diseases and HIV/AIDS, specialty journals, and general medicine reviews. This was done in order to determine just how much of these journals' total 1998 production consisted of articles concerning HIV infection and AIDS. This examination, conducted through a search of the MEDLINE database, predictably revealed greater interest in the HIV/AIDS topic among journals with the highest IF that focus on infectious diseases, though the same interest revealed when examining specialty journals and general medicine periodicals was not negligible.

Home care for persons with AIds: a case-control study to identify determinants of referral to a hospital-based scheme

We conducted a multicenter, hospital-based case-control study to identify specific characteristics of AIDS patients which determine referral to hospital care at home. The cases were patients referred to a hospital-based home care scheme, in the metropolitan area of Rome, during 1997. Each case was matched with two controls. Social, demographic and clinical characteristics were collected at referral. Univariate and multivariate analysis were performed. In the study period, 119 cases and 238 controls were recruited. In logistic regression analysis, social characteristics were not found to affect referral to the hospital-at-home scheme. A severely impaired functional status--assessed by the Functional Independent Measure--identified by a score below 100 (Odds Ratio [OR]=15.2, 95% confidence interval [CI] 2.8-82.7), and the need for prolonged intravenous therapy (OR=12.4, 95% CI=3.3-46.3) were the only two independent predictors of home-care referral. We conclude that home care, even in a period when new potent combination antiretroviral therapies are widely available, is an important integrated service component for persons with AIDS with severe functional impairment or requiring intravenous therapy.

Monitoring the trend of the transmission rate of vertically acquired HIV infection: a simple method applied to Italian data

The objective of this study was to develop and validate a method for estimating and monitoring over time the transmission rate of vertically acquired HIV infection at the population level. We estimated the annual number of children born to HIV-infected women in Italy in 1991-1994 by multiplying the seroprevalence rates, provided by Anonymous Unlinked HIV Serosurveys among Italian Newborns, by the annual number of births, provided by the Italian National Institute of Statistics. The number of HIV-infected children was estimated by applying a simplified back-calculation method to the incident cases of vertically acquired AIDS reported to the AIDS surveillance registry, using seven different estimates of the distribution of the incubation period identified through a literature search. The annual vertical transmission rates were estimated by dividing the estimated number of children with vertically acquired HIV infection by the estimated number of births to an HIV-infected mother. Depending on the chosen distribution of the incubation period, the estimated transmission rate for the four-year period ranges from 0.10 to 0.30. Five of the seven incubation distributions provided a rate falling within the very narrow interval 0.18-0.20. The method provided estimates of vertical transmission rates consistent with those of longitudinal studies performed in European countries. The method presented here could be useful for monitoring the impact of interventions aimed at reducing HIV vertical transmission rate.

Tuberculosis and HIV: a deadly interaction

The spread of the HIV epidemic has been one of the major factors contributing to the worldwide resurgence of the tuberculosis epidemic. It was estimated that in 1997 8% of global tuberculosis cases may be attributed to HIV infection. The highest burden of HIV-associated tuberculosis is concentrated in resource-poor countries. HIV infection increases the individual's susceptibility to tuberculosis by impairing immune response to mycobacterial infection. In addition, HIV-associated tuberculosis is more difficult both to diagnose and to treat. A strong international commitment to the development of innovative strategies of diagnosis, treatment, and the prevention and integration between tuberculosis and HIV prevention programs are urgently needed to face the threat of HIV-associated tuberculosis.

The response of the Italian press to AIDS: a 22-month analysis

This study analyses the way in which the Italian press reported Acquired Immunodeficiency Syndrome (AIDS) over a 22-month period from September 1993 to June 1995, when no national AIDS information campaigns were made in Italy. During this period we collected, read, and categorized every article relating to Human Immunodeficiency Virus (HIV) and AIDS in fourteen newspapers and two news magazines with the highest national circulation. Articles were then assigned to one of six content categories: statistics, basic science, cure and vaccine, education/awareness and prevention issue, government or non-goverment organizations response, and people with AIDS (PWA) personal portrayals. A total of 4,228 articles referring to HIV/AIDS were identified. Analysis of the featured topics reveals several clear differences in the coverage of aspects of AIDS. The major category was represented by government or non-goverment organization response which accounted for 1,341 articles. Overall, this analysis suggests that, even long after the beginning of the epidemic, the press continues to see AIDS as an important issue. However, the articles explaining scientifically the AIDS epidemic were very few. The majority of AIDS-related information was spread in consequence of sensational events. Further analysis of PWA coverage shows that most articles discussed news that could provoke a negative feeling towards HIV-infected patients among the general population.

Sexual behaviour of heterosexual individuals with HIV infection naive for antiretroviral therapy in Italy

BACKGROUND

Specific information about determinants of sexual behaviour of HIV infected heterosexuals, like injecting drug use (IDU), are essential to design interventions aimed at promoting safer sex practices.

METHODS

We analysed data on sexual behaviour collected, between March 1997 and March 1999, through a self administered questionnaire among 1050 IDUs and 642 non-IDU heterosexuals enrolled in a prospective multicentre cohort study on the natural history of HIV infection.

RESULTS

Among non-IDU heterosexuals, more women (48.5%) than men (25.1%) (p<0.001) reported that they were infected by HIV positive regular partners whose HIV status they were not aware of. Among the 1119 heterosexual males, one fifth reported having had more than 25 sexual partners during their lifetime. Condom use in the last sexual intercourse was more common among heterosexual IDUs (64.9%) than among non-IDU heterosexual males (58.3%) (p=0.05). Heterosexual IDU males were more likely (66.7%) than non-IDU heterosexuals (50.6%) to have an HIV negative partner (p<0.001). Of the 573 heterosexual females studied, 10.2% reported having had more than 25 lifetime sex partners. This proportion was higher among heterosexual IDUs (18.8%) than among non-IDU heterosexuals (4.3%) (p<0.001). Nearly 50% of the women in both groups reported having used a condom in the last intercourse. Almost 57% of heterosexual IDUs had a current HIV negative partner, compared with 34.9% non-IDU heterosexuals (p<0.001). In both sexes, the findings from univariate analysis were confirmed by multiple logistic regression analysis.

CONCLUSIONS

This study identified some important differences, in both males and females, in sexual lifestyles according to injecting drug use (for example, in terms of HIV negative partners). This observation indicates the need to tailor HIV prevention messages according to history of injecting drug use.

Changing clinical presentation and survival in HIV-associated tuberculosis after highly active antiretroviral therapy

OBJECTIVE

To assess changes in clinical presentation and outcome of HIV-associated tuberculosis (TB) before and after widespread implementation of highly active antiretroviral therapy (HAART).

METHODS

We reviewed clinical charts of HIV-infected patients with culture-confirmed pulmonary TB in two referral clinical centers in Rome, Italy. The 67 patients diagnosed in 1995 to 1996 were compared with 51 patients diagnosed in 1997 to 1998. To analyze factors associated with survival we used a Cox model including antiretroviral therapy as a time-dependent covariate.

RESULTS

Patients diagnosed in 1997 to 1998 were more likely to have TB as the first AIDS-defining illness (78% versus 58%, p <.05), to have HIV diagnosed <2 months before TB (33% vs. 7%, p <.005) and to have typical chest radiograph pattern (45% vs. 25%, p <.05), and had a higher CD4(+) count (median 105 vs. 43, p <.005). Survival at 1 year was 80% for patients diagnosed in 1997 to 1998 vs. 65% for those diagnosed in 1995 to 1996 (p by log-rank =.02). After adjusting at multivariate analysis, time period of diagnosis was not confirmed as associated with survival (hazard ratio, 1.05; 95% confidence interval, 0.39--2.81). Age, CD4+ cell count <25/mm(3), and AIDS-defining illnesses before TB diagnosis were all associated with an higher risk of death, whereas a decreased risk of death was observed in patients starting a triple combination antiretroviral therapy after TB diagnosis (hazard ratio, 0.14; 95% confidence interval, 0.03--0.57).

CONCLUSIONS

Cases of HIV-associated TB occurring in patients with advanced immunosuppression and presenting with atypical radiologic appearance tend to be relatively less common in the HAART era. HAART is a major factor in prolonging survival in these patients.

Seizure activity produces differential changes in adenosine A1 receptors within rat hippocampus

Specific ligand binding to rat hippocampal adenosine A1 receptor after administration of the convulsant drug 3-mercaptopropionic acid (MP) was studied by means of a quantitative autoradiographic method. 2-Chloro-N6-[cyclopentyl-2,3,4,5-3H adenosine] ([3H]CCPA), a potent and selective A1 receptor ligand, was selected for binding studies. MP administration (150 mg/kg, i.p.), at seizure, caused significant increases in the following CA1 layers: pyramidal (45%), radiatum (18%) and lacunosum molecular (35%); in CA2 area, a significant decrease in stratum oriens (36%) and an increase in stratum radiatum (14%) and lacunosum molecular (33%) layers was observed. In CA3 area a rise in pyramidal (40%) and radiatum layers (26%), as well as in hillus (97%) was found. At postseizure, changes were restricted to CA1, CA2 and CA3 pyramidal layers and to CA1 lacunosum molecular layer, with increases ranging from 22 to 50%. These results show that [3H]CCPA binding is modified diversely in intrahippocampal layers and areas, thus indicating their dissimilar role in seizure activity.