Cristina Mussini

Use in routine clinical practice of two commercial blood tests for diagnosis of infection with Mycobacterium tuberculosis: a prospective study

BACKGROUND Two commercial blood assays for the diagnosis of latent tuberculosis infection--T-SPOT.TB and QuantiFERON-TB Gold--have been separately compared with the tuberculin skin test. Our aim was to compare the efficacy of all three tests in the same population sample. METHODS We did a prospective study in 393 consecutively enrolled patients who were tested simultaneously with T-SPOT.TB and QuantiFERON-TB Gold because of suspected latent or active tuberculosis. 318 patients also had results available for a tuberculin skin test. FINDINGS Overall agreement with the skin test was similar (T-SPOT.TB kappa=0.508, QuantiFERON-TB Gold kappa=0.460), but fewer BCG-vaccinated individuals were identified as positive by the two blood assays than by the tuberculin skin test (p=0.003 for T-SPOT.TB and p<0.0001 for QuantiFERON-TB Gold). Indeterminate results were significantly more frequent with QuantiFERON-TB Gold (11%, 43 of 383) than with T-SPOT.TB (3%, 12 of 383; p<0.0001) and were associated with immunosuppressive treatments for both tests. Age younger than 5 years was significantly associated with indeterminate results with QuantiFERON-TB Gold (p=0.003), but not with T-SPOT.TB. Overall, T-SPOT.TB produced significantly more positive results (38%, n=144, vs 26%, n=100, with QuantiFERON-TB Gold; p<0.0001), and close contacts of patients with active tuberculosis were more likely to be positive with T-SPOT.TB than with QuantiFERON-TB Gold (p=0.0010). INTERPRETATION T-SPOT.TB and QuantiFERON-TB Gold have higher specificity than the tuberculin skin test. Rates of indeterminate and positive results, however, differ between the blood tests, suggesting that they might provide different results in routine clinical practice.

All-cause mortality in treated HIV-infected adults with CD4 ≥500/mm3 compared with the general population: evidence from a large European observational cohort collaboration

BACKGROUND Using data from a large European collaborative study, we aimed to identify the circumstances in which treated HIV-infected individuals will experience similar mortality rates to those of the general population. METHODS Adults were eligible if they initiated combination anti-retroviral treatment (cART) between 1998 and 2008 and had one prior CD4 measurement within 6 months. Standardized mortality ratios (SMRs) and excess mortality rates compared with the general population were estimated using Poisson regression. Periods of follow-up were classified according to the current CD4 count. RESULTS Of the 80 642 individuals, 70% were men, 16% were injecting drug users (IDUs), the median age was 37 years, median CD4 count 225/mm(3) at cART initiation and median follow-up was 3.5 years. The overall mortality rate was 1.2/100 person-years (PY) (men: 1.3, women: 0.9), 4.2 times as high as that in the general population (SMR for men: 3.8, for women: 7.4). Among 35 316 individuals with a CD4 count ≥500/mm(3), the mortality rate was 0.37/100 PY (SMR 1.5); mortality rates were similar to those of the general population in non-IDU men [SMR 0.9, 95% confidence interval (95% CI) 0.7-1.3] and, after 3 years, in women (SMR 1.1, 95% CI 0.7-1.7). Mortality rates in IDUs remained elevated, though a trend to decrease with longer durations with high CD4 count was seen. A prior AIDS diagnosis was associated with higher mortality. CONCLUSIONS Mortality patterns in most non-IDU HIV-infected individuals with high CD4 counts on cART are similar to those in the general population. The persistent role of a prior AIDS diagnosis underlines the importance of early diagnosis of HIV infection.

Changes in the incidence and predictors of human immunodeficiency virus-associated dementia in the era of highly active antiretroviral therapy.

Though effective anti–human immunodeficiency virus (HIV) therapies are now available, they have variable penetration into the brain. We therefore aimed to assess changes over calendar time in the risk for HIV‐associated dementia (HIV‐D), and factors associated with HIV‐D risk.

Performance of tests for latent tuberculosis in different groups of immunocompromised patients.

BACKGROUND Immunocompromised persons infected with Mycobacterium tuberculosis (MTB) have increased risk of tuberculosis (TB) reactivation, but their management is hampered by the occurrence of false-negative results of the tuberculin skin test (TST). The T-cell interferon (IFN)-gamma release blood assays T-SPOT.TB (TS.TB) [Oxford Immunotec; Abingdon, UK] and QuantiFERON-TB Gold In-Tube (QFT-IT) [Cellestis Ltd; Carnegie, VIC, Australia] might improve diagnostic accuracy for latent TB infection (LTBI) in high-risk persons, although their performance in different groups of immunocompromised patients is largely unknown. METHODS AND RESULTS Over a 1-year period, we prospectively enrolled patients in three different immunosuppressed groups, as follows: 120 liver transplantation candidates (LTCs); 116 chronically HIV-infected persons; and 95 patients with hematologic malignancies (HMs). TST, TS.TB, and QFT-IT were simultaneously performed, their results were compared, and intertest agreement was evaluated. Overall, TST provided fewer positive results (10.9%) than TS.TB (18.4%; p < 0.001) and QFT-IT (15.1%; p = 0.033). Significantly fewer HIV-infected individuals had at least one positive test (9.5%) compared with LTCs (35.8%; p < 0.001) and patients with HMs (29.5%; p < 0.001). Diagnostic agreement between tests was moderate (kappa = 0.40 to 0.65) and decreased in the HIV-infected group when the results of the TS.TB were compared with either TST (kappa = 0.16) or QFT-IT (kappa = 0.19). Indeterminate blood test results due to low positive control values were significantly more frequent with QFT-IT (7.2%) than with TS.TB (0.6%; p < 0.001). CONCLUSIONS Blood tests identified significantly more patients as being infected with MTB than TST, although diagnostic agreement varied across groups. Based on these results, we recommend tailoring application of the new blood IFN-gamma assays for LTBI in different high-risk groups and advise caution in their current use in immunosuppressed patients.

Mitochondria alterations and dramatic tendency to undergo apoptosis in peripheral blood lymphocytes during acute HIV syndrome

Objective:To study alterations of mitochondrial membrane potential (Δψ) and the propensity to undergo apoptosis in peripheral blood lymphocytes (PBL) from subjects with acute HIV syndrome; and to evaluate possible modulations of these phenomena by antioxidants that can be used in therapy, such as N-acetyl-cysteine (NAC), nicotinamide (NAM), or L-acetyl-carnitine (LAC). Methods:Mitochondrial function and the tendency of PBL to undergo spontaneous apoptosis were studied on freshly collected PBL from patients with symptomatic, acute HIV-1 primary infection, which were cultured for different durations in the presence or absence of NAC, NAM or LAC. By a cytofluorimetric method allowing analysis of Δψ in intact cells, we studied the function of these organelles under the different conditions. PBL apoptosis was evaluated by the classic cytofluorimetric method of propidium iodide staining, capable of revealing the typical DNA hypodiploid peak. Results:Significant Δψ alterations and tendency to undergo apoptosis were present in PBL from the subjects we studied. Indeed, when cultured even for a few hours in the absence of any stimulus, a consistent number of cells died. However, the presence of even different levels of NAC, NAM or LAC was able to rescue most of them from apoptosis. Both a fall in Δψ and apoptosis were evident in PBL collected in the earliest phases of the syndrome (before seroconversion), and changed significantly after a few days. A significant correlation was found between spontaneous apoptosis and tumour necrosis factor (TNF)-α or p24 plasma levels, as well as between apoptosis and the percentages of circulating CD4+ or CD8+ T cells. Conclusions:PBL from patients with acute HIV syndrome are characterized by both significant mitochondrial alterations and a dramatic tendency to undergo apoptosis. The use of NAC, NAM or LAC seems to rescue cells through a protective effect on mitochondria, a well-known target for the action of TNF-α and for reactive oxygen species, the production of which is strongly induced by this cytokine. Thus, our data could provide the rationale for the use of such agents in addition to antiviral drugs in primary infection.

One-pill once-a-day HAART: a simplification strategy that improves adherence and quality of life of HIV-infected subjects

Objective: The aim of the ADONE (ADherence to ONE pill) study was to verify the effect of a reduced number of pills on adherence and quality of life (QoL) in HIV-infected patients on highly active antiretroviral therapy (HAART). Design: Prospective, multicenter, study. Methods: Patients chronically treated with emtricitabine (FTC) + tenofovir (TDF) + efavirenz (EFV) or lamivudine (3TC) +TDF +EFV and with a HIV-RNA < 50 copies/mL were switched to the single-pill fixed-dose regimen (FDR) of FTC +TDF +EFV. Data were collected with SF-36 using visual analog scales. Results of the final (6 months) primary as-treated analysis are reported. Results: 212 patients (77.4% males) of mean age 45.8 years were enrolled; 202 completed the study. One month post switch to FDR the adherence rate increased significantly to 96.1% from a baseline value of 93.8% (P < 0.01). The increase was steadily maintained throughout the study (96.2% at 6 months). QoL improved over time from 68.8% to 72.7% (P = 0.042) as well, and was significantly associated with the perception of health status, presence of adverse events (AEs) and number of reported AEs (P < 0.0001). QoL significantly influenced adherence (P < 0.0001). During FDR use the mean CD4 count increased from 556 to 605 cells/μL (P < 0.0001). At the end of follow-up 98% of patients maintained HIV-RNA level < 50 copies/mL and 100% <400 copies/mL. Four patients stopped therapy because they were lost to follow-up and 6 because of AEs (insomnia/nervousness 4, allergy 1, difficulties swallowing pills 1). Conclusion: By substituting a one-pill once-a-day HAART, we observed an improvement of both adherence and QoL while maintaining high virologic and immunologic efficacy. HAART simplicity is an added value that favors adherence and may improve long-term success.

The effect of highly active antiretroviral therapy-induced immune reconstitution on development and outcome of progressive multifocal leukoencephalopathy: Study of 43 cases with review of the literature

The authors investigated the effect of highly active antiretroviral therapy (HAART) on the onset and outcome of progressive multifocal leukoencephalopathy (PML) in a group of 43 patients with histological or clinicovirological diagnosis of PML. In eight of these cases (19%), PML symptoms presented 21 to 55 days after the start of HAART, concomitantly with a CD4 cell-count increase and plasma human immunodeficiency virus type 1 (HIV-1) RNA load (VL) decrease. Four of these patients died of PML. Apart from baseline VL, we did not identify any other variable that could distinguish these forms of immune reconstitution PML from those occurring in patients either untreated or failing to respond to therapy. To compare the viroimmunological response to HAART with PML outcome, we evaluated a subgroup of 23 patients untreated at the time of PML onset. No different pattern of response to HAART was observed between patients who died or survived to PML. However, start of HAART was delayed of ≥3 months after onset of PML in half of the latter patients. In conclusion, HAART-associated immune reconstitution seems to play a role on development of a substantial number of PML cases. Although the authors could not demonstrate a directly deleterious effect of HAART on PML progression, prompt initiation of HAART after diagnosis of PML and subsequent successful response were often associated with bad PML outcome.

Prevalence, associated factors, and prognostic determinants of AIDS-related toxoplasmic encephalitis in the era of advanced highly active antiretroviral therapy

BACKGROUND Characteristics, associated factors, and survival probability of toxoplasmic encephalitis (TE) in the era of advanced highly active antiretroviral therapy (HAART) have not been fully clarified. METHODS Data for 205 individuals with acquired immunodeficiency syndrome (AIDS)-related TE were derived from the Italian Registry Investigative NeuroAIDS database, and the cases were studied longitudinally to evaluate prevalence, clinical characteristics, and survival. Moreover, the relationship between the occurrence of TE and exposure to antiretroviral therapy and to TE prophylaxis was evaluated. RESULTS With an overall prevalence of 26%, TE represented the most frequent neurological disorder in the cohort. Female sex, severe immunodeficiency, and absence of primary TE prophylaxis significantly increased the risk of TE, and previous exposure to antiretroviral therapy reduced the probability of disease occurrence. Thirty-six percent of patients who had received antiretroviral therapy developed TE, although in most of these cases, the patient experienced failure of antiretroviral therapy. Of note, 66% of patients who had experienced antiretroviral therapy did not receive prophylaxis for TE at TE diagnosis. The 1-year probability of that infection with human immunodeficiency virus (HIV) would progress or that death would occur after TE was 40% and 23%, respectively. Cognitive symptoms, low CD4(+) cell count, not receiving HAART after TE, and initiating HAART >2 months after TE diagnosis were all significantly associated with an increased probability of progression of HIV infection. Not receiving HAART after diagnosis negatively affected survival. CONCLUSIONS TE remains a highly prevalent disorder of the central nervous system, even in the late HAART era, particularly among severely immunosuppressed patients and in absence of prophylaxis. Considering that persons with TE have a high probability of early death, prophylaxis should be maintained in immunosuppressed patients who experience failure of antiretroviral therapy, and HAART should be initiated as soon as possible after TE diagnosis.

Combination therapy for carbapenem-resistant Gram-negative bacteria

Carbapenem-resistant Gram-negative bacteria (CR-GNB) represent an increasing hazard in healthcare settings. A central question concerning the treatment of invasive infections caused by CR-GNB involves the use of combination therapy. Potential advantages of combination therapy include improved efficacy due to synergy, while the disadvantages include adverse events and increased antibiotic use with a potential drive towards resistance. Several observational studies have examined whether combination therapy offers an advantage over colistin/polymyxin monotherapy. We highlight the inherent limitations of these studies related to their observational design and sample size to show why they do not at present provide an answer to the question of combination versus monotherapy. This distinction is important to guide clinical practice until solid evidence has been obtained and to enable the recruitment of patients into randomized controlled trials. A few randomized controlled trials examining specific combinations have recently been completed or are ongoing. Currently, however, there is no evidence-based support for most combination therapies against CR-GNB, including colistin/carbapenem combination therapy.

Discontinuation of Maintenance Therapy for Cryptococcal Meningitis in Patients with AIDS Treated with Highly Active Antiretroviral Therapy: An International Observational Study

We conducted a retrospective, multicenter study evaluating the safety of discontinuing maintenance therapy for cryptococcal meningitis after immune reconstitution. Inclusion criteria were a previous definitive diagnosis of cryptococcal meningitis, a CD4 cell count of >100 cells/microL while receiving highly active antiretroviral therapy (HAART), and the subsequent discontinuation of maintenance therapy for cryptococcal meningitis. The primary end point was relapse of cryptococcal disease. As of July 2002, 100 patients were enrolled. When maintenance therapy was discontinued, the median CD4 cell count was 259 cells/microL and the median plasma virus load was <2.30 log10 copies/mL, and serum cryptococcal antigen was undetectable in 56 patients. During a median follow-up period of 28.4 months (range, 6.7-64.5; 262 person-years), 4 events were observed (incidence, 1.53 events per 100 person-years; 95% confidence interval, 0.42-3.92). Three of these patients had a CD4 cell count of >100 cells/microL and a positive serum cryptococcal antigen test result during the recurrent episode. In conclusion, discontinuation of maintenance therapy for cryptococcal meningitis is safe if the CD4 cell count increases to >100 cells/microL while receiving HAART. Recurrent cryptococcal infection should be suspected in patients whose serum cryptococcal antigen test results revert back to positive after discontinuation of maintenance therapy.