Challenges and opportunities to prevent tuberculosis in people living with HIV in low-income countries.

People living with the human immunodeficiency virus (HIV) (PLHIV) are at high risk for tuberculosis (TB), and TB is a major cause of death in PLHIV. Preventing TB in PLHIV is therefore a key priority. Early initiation of antiretroviral therapy (ART) in asymptomatic PLHIV has a potent TB preventive effect, with even more benefits in those with advanced immunodeficiency. Applying the most recent World Health Organization recommendations that all PLHIV initiate ART regardless of clinical stage or CD4 cell count could provide a considerable TB preventive benefit at the population level in high HIV prevalence settings. Preventive therapy can treat tuberculous infection and prevent new infections during the course of treatment. It is now established that isoniazid preventive therapy (IPT) combined with ART among PLHIV significantly reduces the risk of TB and mortality compared with ART alone, and therefore has huge potential benefits for millions of sufferers. However, despite the evidence, this intervention is not implemented in most low-income countries with high burdens of HIV-associated TB. HIV and TB programme commitment, integration of services, appropriate screening procedures for excluding active TB, reliable drug supplies, patient-centred support to ensure adherence and well-organised follow-up and monitoring that includes drug safety are needed for successful implementation of IPT, and these features would also be needed for future shorter preventive regimens. A holistic approach to TB prevention in PLHIV should also include other important preventive measures, such as the detection and treatment of active TB, particularly among contacts of PLHIV, and control measures for tuberculous infection in health facilities, the homes of index patients and congregate settings.

Team approach to manage difficult-to-treat TB cases: Experiences in Europe and beyond.

As recommended by the World Health Organization (WHO), optimal management of MDR-TB cases can be ensured by a multi-speciality consultation body known as 'TB Consilium'. This body usually includes different medical specialities, competences and perspectives (e.g., clinical expertise both for adults and children; surgical, radiological and public health expertise; psychological background and nursing experience, among others), thus lowering the risk of making mistakes - or managing the patients inappropriately, in order to improve their clinical outcomes. At present, several high MDR-TB burden countries in the different WHO regions (and beyond) have introduced TB Consilium-like bodies at the national or subnational level to reach consensus on the best treatment approach for their patients affected by TB. In addition, in countries/settings where a formal system of consultation does not exist, specialized staff from MDR-TB reference centres or international organizations usually spend a considerable amount of their working time responding to phone or e-mail clinical queries on how to manage M/XDR-TB cases. The aim of this manuscript is to describe the different experiences with the TB Consilia both at the international level (European Respiratory Society - ERS/WHO TB Consilium) and in some of the countries where this experience operates successfully in Europe and beyond. The Consilium experiences are described around the following topics: (1) history, aims and focus; (2) management and funding; (3) technical functioning and structure; (4) results achieved. In addition a comparative analysis of the TB Consilia in the different countries has been performed.

Comparison of bacteriological conversion and treatment outcomes among MDR-TB patients with and without diabetes in Mexico: Preliminary data.

Diabetes mellitus (DM) is a well-known risk factor for tuberculosis (TB). However, it is not known to what extent DM affects the outcome in patients with multidrug-resistant (MDR-TB) and extensively drug-resistant TB (XDR-TB) treated with second-line anti-TB drugs. The objective of this study was to compare the microbiological evolution (sputum smear and culture conversion) and final outcomes of MDR/XDR-TB patients with and without DM, managed at the national TB reference centre in Mexico City. RESULTS: Ninety patients were enrolled between 2010 and 2015: 73 with MDR-TB (81.1%), 11 with pre-XDR-TB (e.g. MDR-TB with additional resistance to one injectable drug or a fluoroquinolone, 12.2%) and 6 (6.7%) with XDR-TB. Out of these, 49 (54.4%) had DM and 42 (86%) were undergoing insulin treatment. No statistically significant differences were found in treatment outcomes comparing DM vs. non-DM MDR-TB cases: 18/32 (56.3%) of DM cases and 19/24 (79.2%) non DM patients achieved treatment success (p=0.07). The time to sputum smear and culture conversion was longer (although not statistically) in patients without DM, as follows: the mean (±SD) time to sputum smear conversion was 53.9 (±31.4) days in DM patients and 65.2 (±34.8) days in non-DM ones (p=0.15), while the time to culture conversion was 66.2 (±27.6) days for DM and 81.4 (±37.7) days for non-DM MDR-TB cases (p=0.06). CONCLUSIONS: The study results support the Mexican National TB programme to strengthen its collaboration with the DM programme, as an entry point for TB (and latent TB infection) screening and management.

Update on the diagnosis and treatment of pulmonary tuberculosis.

Tuberculosis (TB) remains the most important human infectious disease. Currently, the TB diagnosis is still based on the clinical presentation, radiographic findings and microbiological results; all of which have sensitivity or specificity issues. For that reason, the immediate future involves rapid molecular microbiological techniques, in particular GeneXpert (which is more sensitive than bacilloscopy and is able to detect rifampicin resistance) and GenoType. The current six-month treatment for TB has remained unchanged for decades. Attempts to shorten this treatment have failed. In recent years, new drugs have been reported that could contribute to TB treatment in the near future, and are already being used in multi-drug-resistance TB.

Comparative efficacy of bronchoalveolar lavage and telescoping plugged catheter in the diagnosis of pneumonia in mechanically ventilated patients.

The relative efficacy of telescoping plugged catheter (TPC) and bronchoalveolar lavage (BAL) in the diagnosis of pneumonia in mechanically ventilated patients has been compared in 45 subjects suspected of having pneumonia because of the presence of clinical and radiographic criteria. Diagnosis of pneumonia was strongly suggested in 25 of the 45 patients, and definitely confirmed in 10 of them. The diagnostic threshold to assess a quantitative bacterial culture as positive was a growth on BAL of > or = 10(5) cfu/ml and on TPC of > or = 10(3) cfu/ml. The BAL specimen cultures established the diagnosis in 19 cases (76 percent). In the remaining six patients, this technique did not permit the assessment of the diagnosis, which was established by other procedures (TPC, blood cultures, clinical outcome, or autopsy). False-positive results were not found. Sensitivity and specificity for BAL cultures were 76 percent and 100 percent, respectively. Telescoping plugged catheter established the presence of pneumonia in 16 patients (64 percent). Combining both techniques, the sensitivity increased up to 88 percent, maintaining specificity of 100 percent. In summary, BAL has a greater sensitivity than TPC in the diagnosis of pneumonias in mechanically ventilated patients. However, they are procedures that can complement each other.

[The usefulness of elastin fibers as a diagnostic marker in ventilator-related pneumonia]. / Utilidad de las fibras de elastina como marcador diagnóstico de la neumonía asociada al ventilador.

The diagnosis of nosocomial pneumonia is especially difficult in intubated patients due to the low specificity of their clinico-radiological signs. The objective of this study was to evaluate the usefulness of basing diagnosis on elastin fibers (EF) in bronchoaspirate (BAS) as an indication of pneumonia in mechanically-ventilated (MV) patients. Forty-seven MV patients suspected of having nosocomial pneumonia were studied prospectively. Fiber bronchoscopy was carried out on all patients and samples were obtained using a protected catheter brush (PCB) and bronchoalveolar lavage (BAL). A purulent sample of BAS was also examined, after addition of 40% KOH, to determine the presence of EF. EF was found in 15 patients, 11 of whom had pneumonia while 3 more had necrotizing pneumonia (sensitivity 52%, specificity 85%). Ten of the 17 microorganisms isolated in the cases of EF positive pneumonia were gram negative, although the germ found most often was S. aureus. There were no differences in the prognosis for pneumonia patients who were EF positive and those who were EF negative. In conclusion, once necrotizing pneumopathology has been ruled out, the presence of EF in BAS may offer reasonable support for firm diagnosis in some MV patients with pneumonia.

[The efficacy of bronchoalveolar lavage in the diagnosis of pulmonary tuberculosis]. / Rentabilidad del lavado broncoalveolar en el diagnóstico de la tuberculosis pulmonar.

In order to analyze the usefulness of bronchoalveolar lavage (BAL) for conventional microbiological diagnosis of tuberculosis (TB) and other mycobacteria, and to assess the need to use it or not as a routine diagnostic technique in these diseases, we studied 30 patients with mycobacteria (26 TB and 4 Mycobacterium avium-intracellulare infections) by bronchoscopy, with BAL and bronchoaspirate (BAS) bacteriological analyses also available. The results were compared with those obtained for sputum taken before and after bronchoscopy when these specimens were available. The overall yield for BAL and BAS cultures was 90%, with BAL (83.3%) specimens being more productive than BAS (73.3%) specimens. Both performed far better than the 53.8% recorded for cultures of pre-bronchoscopy sputum and 60% for post-bronchoscopy sputum. BAL was the only diagnostic specimen from 7 patients, while BAS the only one from 4. Sensitivity was similar for the two mycobacteria studied. The results for direct bacilloscopy, however, at 30% for the two specimens, rose to 36.6% when they were analyzed together with BAS and BAL. We conclude that bronchoscopy should be performed on all patients suspected of mycobacterial infection when sputum bacilloscopy is negative and patients have no expectoration. Performance of BAL should be routine since this simple and usually uncomplicated technique produces the most productive specimens.