Tuberculosis Exacerbates HIV-1 Infection through IL-10/STAT3-Dependent Tunneling Nanotube Formation in Macrophages.

The tuberculosis (TB) bacillus, Mycobacterium tuberculosis (Mtb), and HIV-1 act synergistically; however, the mechanisms by which Mtb exacerbates HIV-1 pathogenesis are not well known. Using in vitro and ex vivo cell culture systems, we show that human M(IL-10) anti-inflammatory macrophages, present in TB-associated microenvironment, produce high levels of HIV-1. In vivo, M(IL-10) macrophages are expanded in lungs of co-infected non-human primates, which correlates with disease severity.

Training tuberculosis laboratory workers in LED-fluorescence microscopy: experience learned in Argentina.

Objective: To assess a LED-fluorescence microscopy (LED-FM) capacitation program for the training of laboratory technicians without previous experience in FM.

Methods: We evaluated a teaching program that consists of a three-day course followed by an "in situ" two-month phase in which technicians acquired skills without the help of a FM expert; in order to gain confidence to recognize auramine-stained bacillus, during this phase, technicians examined duplicate slides stained by Ziehl Neelsen (ZN) and FM in a unblinded way. Technicians with acceptable performance, continued with a blinded-training period.

Fluoromycobacteriophages Can Detect Viable and Determine Phenotypic Rifampicin Resistance in 3-5 Days From Sputum Collection.

The World Health Organization (WHO) estimates that 40% of tuberculosis (TB) cases are not diagnosed and treated correctly. Even though there are several diagnostic tests available in the market, rapid, easy, inexpensive detection, and drug susceptibility testing (DST) of is still of critical importance specially in low and middle-income countries with high incidence of the disease. In this work, we have developed a microscopy-based methodology using the reporter mycobacteriophage ϕ for detection of and phenotypic determination of rifampicin resistance within just days from sputum sample collection.

Formation of Foamy Macrophages by Tuberculous Pleural Effusions Is Triggered by the Interleukin-10/Signal Transducer and Activator of Transcription 3 Axis through ACAT Upregulation.

The ability of (Mtb) to persist in its human host relies on numerous immune evasion strategies, such as the deregulation of the lipid metabolism leading to the formation of foamy macrophages (FM). Yet, the specific host factors leading to the foamy phenotype of Mtb-infected macrophages remain unknown. Herein, we aimed to address whether host cytokines contribute to FM formation in the context of Mtb infection.

[Performance of LED fluorescence microscopy for the detection of acid-fast bacilli from respiratory samples in peripheral laboratories in Argentina].

Introduction: Light-emitting diode fluorescence microscopy (LED-FM) has been endorsed by the World Health Organization (WHO) for tuberculosis diagnosis, but its accuracy in HIV-infected patients remains controversial, and only some few studies have explored procedural factors that may affect its performance.

Objective: To evaluate the performance of LED-FM for tuberculosis diagnosis in patients with and without HIV infection using a newer, less expensive LED lamp.

Materials And Methods: We compared the performance of LED-FM and Ziehl-Neelsen (ZN) microscopy on respiratory specimen smears from tuberculosis (TB) suspects and patients on treatment examined by different technicians blinded for HIV-status and for the result of the comparative test.

LED fluorescence microscopy in the diagnosis of tuberculosis: Fading and restaining of smears for external quality assessment.

Blinded rechecking is a method proposed for external quality assurance (EQA) of auramine-stained acid-fast bacilli (AFB) smears using fluorescence microscopy (FM), however, this procedure is not well developed and slides fading over time could compromise its implementation. Since bleaching of fluorescent molecules involves temperature-dependent chemical reactions, it is likely that low temperatures could slow down this process. We stored auramine-stained slides under different environmental conditions, including -20°C, and examined them over time.

First series of patients with XDR and pre-XDR TB treated with regimens that included meropenen-clavulanate in Argentina.

XDR (extensively drug-resistant) and pre-XDR tuberculosis (TB) seriously compromise prognosis and treatment possibilities, and inevitably require the use of group V drugs (World Health Organization). The progress of all patients with XDR and pre-XDR TB seen in a specialized unit during 2012 and 2013 and treated with regimens that included at least 6 months of meropenem-clavulanate (MPC), capreomycin, moxifloxacin, linezolid, clofazimine, high-dose isoniazid, PAS, and bedaquiline in 1 case, were retrospectively analysed. Ten patients were treated, 9 with an extensive pattern of resistance to at least 6 drugs, and 1 because of adverse reactions and drug interactions leading to a similar situation.

Molecular epidemiology of Mycobacterium tuberculosis, Buenos Aires, Argentina.

To analyze the molecular epidemiology of Mycobacterium tuberculosis strains at a hospital in Buenos Aires, Argentina, and mutations related to multidrug-resistant and extensively drug-resistant tuberculosis, we conducted a prospective case-control study. Our findings reinforce the value of incorporating already standardized molecular methods for rapidly detecting resistance.

Human Mycobacterium bovis infection in ten Latin American countries.

The aim of this work was to obtain the best possible estimate of the relevance of bovine tuberculosis (BTB) in humans in Argentina, Brazil, Chile, Colombia, Costa Rica, Dominican Republic, Ecuador, Peru, Uruguay and Venezuela. Sources of information were a questionnaire filled by the participant laboratories, and a search of published literature (1970-2007). Only four of these countries reported bacteriologically confirmed cases of BTB in humans.

Tuberculous meningitis in HIV-infected patients: drug susceptibility and clinical outcome.

The objective of this study was to identify prognostic factors of death in patients with tuberculous meningitis (TM) and show the impact of infection by multidrug-resistant strains on the outcome of this disease. We retrospectively analysed clinical charts of HIV-infected patients with culture-confirmed TM attending our institution during 1996-2004. The following variables were associated with death during hospitalization: neurological signs at admission, a CD4 T-cell count less than 50 cells/microl and infection by multidrug-resistant strains.

[Multidrug-resistant tuberculosis in AIDS patients at the beginning of the millennium].

AIDS-related multidrug-resistant tuberculosis (MDRTB) emerged during the 90s in several countries around the world. In Argentina, the most notorious outbreak was documented in the Hospital Muñiz, which is still undergoing its aftermaths. In order to evaluate the situation in this hospital regarding MDRTB, we analysed clinical, demographic and epidemiological traits of the 53 male MDRTB-aids patients admitted during 2001-2003 at a ward especially dedicated to their isolation.

[Evaluation of the control measures adopted against an epidemic of AIDS-related multidrug-resistant tuberculosis in a Latin-American hospital].

Background: Since 1992 AIDS-related multidrug-resistant tuberculosis (MDRTB) has been detected among patients admitted to the Hospital Muñiz in Buenos Aires (Argentina). The aim of the present study was to evaluate the effectiveness of the control measures adopted against the nosocomial spread of MDRTB/AIDS, which affected 803 patients between 1992 and 2002.

Methods: An action plan was applied that included bacilloscopy screening on admission, isolation rooms for patients with TB/AIDS, an isolation ward for patients with MDRTB/AIDS, a radiometric method for the diagnosis of multidrug-resistance, a reserve supply of second line drugs, and respiratory protection for health care workers.

[Mastitis due to Mycobacterium fortuitum in an HIV negative patient].

A case of a 39 year old HIV negative female patient with a Mycobacterium fortuitum mastitis without previous pathogenic history is reported. She was treated on the bases of drug-susceptibility testing and bibliographic empirical evidence with kanamycin, doxicicline, ciprofloxacin and trimetoprim-sulfametoxazol. A complete remission of her lesions was obtained after 15 months of treatment.

Multidrug-resistant tuberculosis in HIV-negative patients, Buenos Aires, Argentina.

Initial multidrug-resistant (MDR) tuberculosis (TB) in HIV-negative patients treated at a Buenos Aires referral hospital from 1991 to 2000 was examined by using molecular clustering of available isolates. Of 291 HIV-negative MDRTB patients, 79 were initially MDR. We observed an ascending trend of initial MDRTB during this decade (p=0.