Resistance to first-line antituberculosis drugs in Spain, 2010-2011. RETUBES Study

Evaluation of the Integrated Tuberculosis Research Program Sponsored by the Spanish Society of Pulmonology and Thoracic Surgery: 11 Years on

OBJECTIVE

The objective of the study was to determine the trend of variables related to tuberculosis (TB) from the Integrated Tuberculosis Research Program (PII-TB) registry of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR), and to evaluate the PII-TB according to indicators related to its scientific objectives.

METHOD

Cross-sectional, population-based, multicenter study of new TB cases prospectively registered in the PII-TB between 2006 and 2016. The time trend of quantitative variables was calculated using a lineal regression model, and qualitative variables using the χy test for lineal trend.

RESULTS

A total of 6,892 cases with an annual median of 531 were analyzed. Overall, a significant downward trend was observed in women, immigrants, prisoners, and patients initially treated with 3 drugs. Significant upward trends were observed in patients aged 40-50 and > 50 years, first visit conducted by a specialist, hospitalization, diagnostic delay, disseminated disease and single extrapulmonary location, culture(+), sensitivity testing performed, drug resistance, directly observed treatment, prolonged treatment, and death from another cause. The scientific objectives of the PII-TB that showed a significant upward trend were publications, which reached a maximum of 8 in 2016 with a total impact factor of 49,664, numbers of projects initiated annually, presentations at conferences, and theses.

CONCLUSIONS

PII-TB provides relevant information on TB and its associated factors in Spain. A large team of researchers has been created; some scientific aspects of the registry were positive, while others could have been improved.

Association between tobacco smoking and drug-resistant tuberculosis

Background

Tobacco smoking is a risk factor for tuberculosis but little is known about the relationship between tobacco smoking and drug-resistant tuberculosis (DR-TB). We undertook a systematic review and meta-analysis to quantitatively assess the association between DR-TB and tobacco smoking.

Methods

We searched for relevant studies in the Ovid MEDLINE, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, WANFANG, and WEIPU data-bases from inception to September 1, 2017. Results were expressed as odds ratios (ORs) with accompanying 95% CIs, and subgroup analyses were performed by study design, smoking type, DR-TB type, and multivariate analysis.

Results

Thirty-three studies related to tobacco smoking and DR-TB were included. We found substantial evidence that tobacco smoking is associated with an increased risk of DR-TB (OR 1.57, 95% CI 1.33–1.86). Associations were also found in subgroup analyses: for multidrug-resistant tuberculosis (OR 1.49, 95% CI 1.19–1.86) and for any DR-TB (OR 1.70, 95% CI 1.3–2.23); the pooled OR was 1.45 (95% CI 1.11–1.90) for current smoking, 2.25 (95% CI 1.46–3.47) for past smoking, and 1.56 (95% CI 1.22–1.98) for smoking history; and similar ORs were also observed in study design and multivariate analysis subgroup analysis.

Conclusion

This study demonstrated that tobacco smoking is an independent risk factor for DR-TB.

The changing epidemiology of tuberculosis in a Spanish tertiary hospital (1995-2013)

Important epidemiological changes and improvement of new diagnostic approaches, mainly molecular tools, might have impacted the management and outcome of tuberculosis (TB) in the last years in industrialized countries. In order to describe the epidemiological trends, and changes in clinical, diagnostic, and therapeutic aspects in patients with TB, an observational study was performed in a tertiary hospital in Western Europe (Madrid, Spain).All adult patients (>16 years) with a diagnosis of TB in the period 1995 to 2013 were included in the study.TB was diagnosed in 1284 patients, including 304 (24%) foreign-born and 298 (23.2%) human immunodeficiency virus (HIV)-infected patients. The proportion of foreign-born patients increased significantly, from 7.4% (1995) to 40.3% (2013), P < .001, while the proportion of patients with HIV infection decreased (from 41% to 15%, P < .001). Extrapulmonary locations of TB increased (from 23.9% to 37.1%, P < .001), although the miliary forms were less frequent (from 16% to 5.6%, P < .001). Pulmonary involvement remained constant during the period of study (from 50% to 46%, P = .18). The yield of microbiological diagnostic methods in different clinical specimens has remained very similar. Only molecular techniques have improved the diagnosis in respiratory, urinary, and peritoneal samples. The global cure rate was 64.8% and mortality rate was 9.1% (6.5% directly attributable to TB). Mortality has decreased significantly during the years of study (from 11% to 2%, P < .001).There has been a significant decline in the number of patients with TB. Changes in HIV coinfection and immigration have conditioned other epidemiological and clinical aspects of the disease, including the clinical presentation, treatment response, and mortality. Only the use of molecular tests has provided an improvement in the diagnosis of pulmonary and extrapulmonary TB.

Utility of Phenotypic and Genotypic Testing in the Study of Mycobacterium tuberculosis Resistance to First-Line Anti-Tuberculosis drugs

OBJECTIVE

To determine the utility of molecular techniques in the diagnosis of resistance and the extent of resistance to first-line drugs in our region.

MATERIAL AND METHOD

From 2004 to 2013, 1,889 strains of Mycobacterium tuberculosis complex isolated in Asturias, Spain, were studied using phenotypic (Clinical and Laboratory Standards Institute guidelines) and molecular (INNOLiPA RIF-TB^©; GenotypeMDRplus^©; GenotypeMDRsl^©) sensitivity tests.

RESULTS

1,759 strains (94.52%) were sensitive to all first-line drugs, and 102 strains (5.48%) showed some resistance: 81 strains (4.35%) were resistant to 1 single drug, 14 (0.75%) were polyresistant, and 7 (0.37%) were multiresistant (resistant to rifampicin and isoniazid). In total, 137 resistances were identified: 60 to isoniazid (3.22%), 7 to rifampicin (0.37%), 9 to pyrazinamide (0.48%), 11 to ethambutol (0.59%), and 50 to streptomycin (2.68%). Of the mutations detected, 75.9% (63/83) correlated with resistance, while 24.09% of mutations detected (20/83) were not associated with resistance; 16 of these involved a silent mutation at codon 514 of the rpoB gene. Between 0 and 90% of strains, depending on the drug under consideration, were resistant even when no gene mutations were detected using marketed systems.

CONCLUSIONS

Molecular techniques are very useful, particularly for obtaining rapid results, but these must be confirmed with standard phenotypic sensitivity testing. The rate of resistance in our region is low and multi-drug resistantcases (0.37%) are sporadic.

Factors Associated with Fatality during the Intensive Phase of Anti-Tuberculosis Treatment

OBJECTIVE

To determine the case-fatality rate (CFR) at the end of the intensive phase of tuberculosis (TB) treatment, and factors associated with fatality.

METHODS

TB patients diagnosed between 2006 and 2013 were followed-up during treatment. We computed the CFR at the end of the intensive phase of TB treatment, and the incidence of death per 100 person-days (pd) of follow-up. We performed survival analysis using the Kaplan-Meier method and Cox regression, and calculate hazard ratios (HR) and 95% confidence intervals (CI).

RESULTS

A total of 5,182 patients were included, of whom 180 (3.5%) died; 87 of these deaths (48.3%) occurred during the intensive phase of treatment, with a CFR of 1.7%. The incidence of death was 0.028/100 pd. The following factors were associated with death during the intensive phase: being >50 years (HR = 36.9;CI:4.8-283.4); being retired (HR = 2.4;CI:1.1-5.1); having visited the emergency department (HR = 3.1;CI:1.2-7.7); HIV infection (HR = 3.4;CI:1.6-7.2); initial standard treatment with 3 drugs (HR = 2.0;CI:1.2-3.3) or non-standard treatments (HR = 2.68;CI:1.36-5.25); comprehension difficulties (HR = 2.8;CI:1.3-6.1); and smear-positive sputum (HR = 2.3-CI:1.0-4.8).

CONCLUSION

There is a non-negligible CFR during the intensive phase of TB, whose reduction should be prioritised. The CFR could be a useful indicator for evaluating TB programs.

Tuberculosis Costs in Spain and Related Factors

OBJECTIVE

To analyze the direct and indirect costs of diagnosis and management of tuberculosis (TB) and associated factors.

PATIENTS AND METHODS

Prospective study of patients diagnosed with TB between September 2014 and September 2015. We calculated direct (hospital stays, visits, diagnostic tests, and treatment) and indirect (sick leave and loss of productivity, contact tracing, and rehabilitation) costs. The following cost-related variables were compared: age, gender, country of origin, hospital stays, diagnostic testing, sensitivity testing, treatment, resistance, directed observed therapy (DOT), and days of sick leave. Proportions were compared using the chi-squared test and significant variables were included in a logistic regression analysis to calculate odds ratio (OR) and corresponding 95% confidence intervals.

RESULTS

319 patients were included with a mean age of 56.72±20.79 years. The average cost was €10,262.62±14,961.66, which increased significantly when associated with hospital admission, polymerase chain reaction, sputum smears and cultures, sensitvity testing, chest computed tomography, pleural biopsy, drug treatment longer than nine months, DOT and sick leave. In the multivariate analysis, hospitalization (OR=96.8; CI 29-472), sensitivity testing (OR=4.34; CI 1.71-12.1), chest CT (OR= 2.25; CI 1.08-4.77), DOT (OR=20.76; CI 4.11-148) and sick leave (OR=26,9; CI 8,51-122) showed an independent association with cost.

CONCLUSION

Tuberculosis gives rise to significant health spending. In order to reduce these costs, more control of transmission, and fewer hospital admissions would be required.

[Tuberculosis and immigration]

The incidence of tuberculosis worldwide is declining. However, in Western countries this decline is slower due to the impact of immigration. Tuberculosis in the immigrant population is related to health status in the country of origin and with overcrowding and poverty conditions in the host country. Immigrants with tuberculosis are younger, have a higher prevalence of extrapulmonary forms, greater proportion of drug resistance and higher treatment default rates than those of natives. New molecular techniques not only reduce diagnostic delay time but also allow the rapid identification of resistances and improve knowledge of transmission patterns. It is necessary to implement measures to improve treatment compliance in this population group like facilitating access to health card, the use of fixed-dose combination drugs, the participation of cultural mediators and community health workers and gratuity of drugs.

Spanish Compliance With Guidelines for Prescribing Four Drugs in the Intensive Phase of Standard Tuberculosis Treatment

INTRODUCTION

International and Spanish guidelines recommend a 4-drug regimen in the intensive treatment of tuberculosis (TB). The aim of our study was to determine if these recommendations are followed in Spain, and the factors associated with the use of 3 drugs (standard regimen without ethambutol).

METHODOLOGY

Observational, multicenter, retrospective analysis of data from patients diagnosed with TB in practically all Spanish Autonomous Communities between 2007 and 2102. Factors associated with the use of 3 drugs were analyzed using logistic regression, and odds ratios (OR) and corresponding 95% confidence intervals (CI) were calculated.

RESULTS

A total of 3,189 patients were included, 1,413 (44.3%) of whom received 3 drugs. The percentage of 3-drug users among patients with positive sputum smear was 41.2%; among patients with resistance to at least 1 drug, 36.1%; among HIV-infected patients, 31.4%; and among immigrants, 24.8%. Factors associated with the use of 3 drugs were: female sex (OR=1.18; CI: 1.00-1.39); native Spanish (OR=3.09; CI: 2.58-3.70); retired (OR=1.42; CI: 1.14-1.77); homeless (OR=3.10; CI: 1.52-6.43); living alone (OR=1.62; CI: 1.11-2.36); living in a family (OR=1.97; CI: 1.48-2.65); seen by specialists in the region (OR=1.37; CI: 1.10;1.70); no HIV infection (OR=1.63; CI: 1.09-2.48); and negative sputum smear with positive culture (OR=1.59; CI: 1.25-2.02).

CONCLUSIONS

A large proportion of TB patients receive intensive treatment with 3 drugs. TB treatment recommendations should be followed, both in routine clinical practice and by the National Plan for Prevention and Control of Tuberculosis in Spain.

Anal tuberculosis complicating anti-TNFα therapy

A 42-year-old man receiving anti-tumour necrosis factor α (anti-TNFα) therapy with adalimumab due to psoriatic arthritis presented with a 2-month-old anal ulcer. An apical right lung infiltrate was found in his chest X-ray, although he had no pulmonary symptoms. Two biopsies of the ulcer were taken and reported as granulomatous, necrotising, with chronic inflammation (first), and as hyperplasic epidermis with linfocitary infiltrate and the presence of plenty of plasmatic cells (second). Histochemical techniques, including Ziehl-Neelsen, Grocott and periodic acid-Schiff stains, and PCR for Mycobacterium tuberculosis on both biopsies were negative. Serology for HIV, syphilis and hepatitis were also negative. In the second biopsy culture, moderate colonies of M. tuberculosis finally grew. The patient started a four-drug antituberculosis regimen. Adalimumab was discontinued and etanercept introduced after 2 months of antituberculosis therapy. The patient remained on therapy for 9 months with complete ulcer resolution.