C. Y. Chiang

Xpert® MTB/RIF for national tuberculosis programmes in low-income countries: when, where and how?

Xpert ® MTB/RIF offers new and important possibilities for the diagnosis of sputum smear-negative tuberculosis (TB) and/or rifampicin (RMP) resistance, and many are encouraging rapid and widespread implementation. This simple test can be implemented almost everywhere, and it provides results within a few hours. In low-income countries (LICs), however, its cost, environmental limitations (stable and regular electricity, adequate room temperature) and difficulties involved in supply and maintenance are major obstacles. While it may be suitable for major reference hospitals, operational research is needed to evaluate the test and its additional yield above high-quality smear microscopy and clinical algorithms before its use at the peripheral level. In the meantime, direct microscopy should remain the initial diagnostic test for TB suspects. In most LICs, the prevalence of RMP resistance among new TB patients is very low; an Xpert MTB/RIF result indicating RMP resistance will thus always need confirmation by another test. In a population at high risk of RMP resistance (> 15%), however, the positive predictive value for RMP resistance by Xpert MTB/RIF is high, and identification of RMP resistance is an excellent proxy for multidrug-resistant TB (MDR-TB). The assay should be widely used for this purpose if, and only if, excellent MDR-TB management is available, both for ethical reasons and to reduce the risk of extensively drug-resistant TB.

Diabetes is associated with drug-resistant tuberculosis in Eastern Taiwan

We assessed the association between diabetes mellitus and drug-resistant tuberculosis (TB). Among new patients, diabetes was significantly associated with any resistance to isoniazid excluding multidrug-resistant TB (MDR-TB; adjusted OR [aOR] 1.88, 95%CI 1.07-3.31), but not with MDR-TB (aOR 0.95, 95%CI 0.34-2.68). Among previously treated patients, diabetes was also significantly associated with INH resistance (aOR 6.76, 95%CI 1.53-29.98) but not with MDR-TB (aOR 1.52, 95%CI 0.59-3.95). We concluded that diabetes was associated with INH resistance and speculated that the sample size of retreatment cases was insufficient to confirm the association between diabetes and MDR-TB.We assessed the association between diabetes mellitus and drug-resistant tuberculosis (TB). Among new patients, diabetes was significantly associated with any resistance to isoniazid excluding multidrug-resistant TB (MDR-TB; adjusted OR [aOR] 1.88, 95%CI 1.07-3.31), but not with MDR-TB (aOR 0.95, 95%CI 0.34-2.68). Among previously treated patients, diabetes was also significantly associated with INH resistance (aOR 6.76, 95%CI 1.53-29.98) but not with MDR-TB (aOR 1.52, 95%CI 0.59-3.95). We concluded that diabetes was associated with INH resistance and speculated that the sample size of retreatment cases was insufficient to confirm the association between diabetes and MDR-TB.

Gatifloxacin for short, effective treatment of multidrug-resistant tuberculosis.

The 9-month regimen for the treatment of multidrug-resistant tuberculosis (MDR-TB) piloted in Bangladesh and used, with modifications, in Cameroon and Niger, has achieved treatment success in a very large proportion of patients; gatifloxacin (GFX) is likely to have played a critical role in this success. Two months after the publication of a study reporting that GFX and not moxifloxacin (MFX) was associated with dysglycaemia, the manufacturer announced the withdrawal of GFX from the market. The findings of that study may have less significance for the majority of MDR-TB patients living in high-incidence countries who are much younger, have a lower risk of dysglycaemia and suffer from a highly fatal condition. The problem of dysglycaemia is not limited to GFX use and may occur with other fluoroquinolones; furthermore, GFX-associated dysglycemia was manageable among those MDR-TB patients in Bangladesh and Niger in whom it occurred. GFX has now become unavailable in Bangladesh, Cameroon, Niger and other countries piloting the shorter MDR-TB regimens, depriving resource-poor countries of an efficacious, effective and inexpensive drug with a demonstrated good safety profile for the given indication. There is little reason not to make GFX available for MDR-TB treatment as long as the superiority of non-GFX-based MDR-TB regimens is not demonstrated.

Standard case management of asthma in Sudan: a pilot project.

SETTING A pilot project for asthma management in selected hospitals in Khartoum and Gezira States, Sudan. OBJECTIVE To assess standard case management of asthma in 2007-2008. DESIGN Local adaptation of guidelines, followed by situational analysis, pre-intervention study, training and implementation. Treatment outcome was assessed 1 year after patient enrolment. RESULTS Situational analysis revealed that inhaled beclometasone was not available in the public sector. During the project, 2068 patients were enrolled: severity of asthma was intermittent in 185 (9.0%), mild persistent in 231 (11.2%), moderate persistent in 640 (31.0%), severe persistent in 812 (39.3%) and unclassified in 200 (9.7%). Of the 1654 patients with persistent asthma who were treated with inhaled corticosteroids, 1157 (70.0%) had treatment cards available for outcome assessment. Of these, 652 (56.4%) did not attend their annual evaluation, among whom 1 (0.1%) died and 651 (56.3%) were lost to follow-up. Of the 505 patients who attended their annual evaluation, 417 (82.6%) improved, 32 (6.3%) were stable and 56 (11.1%) were worse. The frequency of emergency visits and hospitalisation decreased substantially among those who presented for the 1 year follow-up assessment. CONCLUSION The results of standard case management of asthma were encouraging; however, a high proportion of patients did not return for long-term management.

Management of asthma in resource-limited settings: role of low-cost corticosteroid/β-agonist combination inhaler.

The management of asthma requires medicines that are effective in relaxing airway smooth muscles and in reducing airway inflammation. Rapid-acting β₂ agonist is a bronchodilator that provides quick symptom relief in patients with asthma. However, it does not effectively address the underlying problem of airway inflammation. Excess use of inhaled bronchodilators alone for symptom relief may result in delay in seeking health care, which in turn may result in delayed use of anti-inflammatory agents. Inhaled corticosteroid (ICS) is critical in the treatment of airway inflammation; it reduces the risk of life-threatening asthma attacks and the need for hospitalisation. ICS is underused, however, and a substantial proportion of patients with persistent asthma in resource-limited settings have no access to affordable ICS for long-term treatment. International guidelines recommend the use of rapid-acting β-agonists as needed as rescue treatment when symptoms occur. Studies have shown that the use of both ICS and rapid-acting β-agonist as needed for symptom relief might be a better option. The combination of ICS and rapid-acting bronchodilator in a single inhaler is currently too expensive and is not affordable for the poor. Although ICS and short-acting β₂ agonist (SABA) for rescue treatment can be obtained to a certain extent by using separate ICS and SABA inhalers, the first step is to ensure access to affordable, quality-assured essential asthma medicine in resource-limited settings.

World Spirometry Day: intention to test should be intention to treat.

The increasing frequency of chronic respiratory disease1 is the justification for World Spirometry Day (WSD), a global initiative organised by the Forum of International Respiratory Societies (FIRS). WSD originated from the experience of public spirometry events during Congresses of the European Respiratory Society, where free spirometry was offered to the general public with the aim of raising awareness about lung health and diseases. During the first WSD, on 14 October 2010,2 a total of 102 487 lung function tests were performed: 67% in Europe, 13% in South America, 8% in Australasia, 6% in North America, 5% in Asia, and 0.01% (12 tests) in Africa.3 The second WSD, on 27 June 2012, will be an opportunity to raise awareness about lung health, although its objectives need to be clarified. While spirometry is recommended for the diagnosis of airflow limitation in patients with respiratory symptoms, several professional societies recommend against using it in individuals without respiratory symptoms, as it involves substantial cost and may result in over-diagnosis due to false-positive results, unnecessary disease labelling, and inadequate use of medicine without clear benefit in reducing future risks of exacerbation and lung function decline.4 Further, providing individuals with their spirometry results was not found to independently improve smoking cessation or the likelihood of continued abstinence.4 WSD should therefore aim at raising awareness about lung health, but not at using spirometry screening among asymptomatic individuals. As screening without adequate follow-up care will yield no benefit, intention to test should be intention to treat. The contribution of WSD in improving the management of patients with chronic airflow limitation in resource-limited settings should also be clarified. Unfortunately, quality-assured essential medicine, such as inhaled corticosteroids and bronchodilators, for patients with airflow limitation may not be accessible or affordable in low- and middle-income countries.5 Even simple diagnostic tools such as peak flow meters are usually not available, let alone spirometers, and large numbers of patients in resource-limited settings repeatedly make unplanned health visits due to asthma attacks or exacerbations of chronic obstructive pulmonary disease in the absence of long-term management and care. Intention to treat therefore demands a system-wide approach to address the needs of the vulnerable.

Insights into drug-resistant tuberculosis treatment: results of The Union DR-TB Working Group Survey, 2017

The past 4 years have seen the introduction of new regimens and new drugs to treat multidrug-resistant tuberculosis (MDR-TB). To identify implementation trends over time, the DR-TB Working Group of the International Union Against Tuberculosis and Lung Disease (The Union), in collaboration with RESIST-TB, launched an online survey to Union members around the world. Survey results showed substantial diversity in treatment roll-out: 36% of respondents stated that their country is using the 9-month regimen for MDR-TB treatment; 41% are using bedaquiline and delamanid, but not the 9-month regimen; 28% are using both; and 22% of respondents indicated that their country does not currently offer either of these treatment options. Survey respondents also identified specific challenges to the introduction of shorter MDR-TB regimens and new drugs, including access to rapid diagnosis of fluoroquinolone resistance and case management. The results of this survey are intended to help identify research and implementation gaps while highlighting the importance of global implementation of scalable regimens for the treatment of MDR-TB.