Monitoring the quality of laboratories and the prevalence of resistance to antituberculosis drugs: Italy, 1998-2000

Epidemiology and treatment outcome of MDR and pre-XDR TB in international migrants at two reference centers in the North of Italy: a cross-sectional study coordinated by Stop TB Italia Onlus

OBJECTIVE

We evaluated the epidemiology and treatment outcomes of multi-drug-resistant (MDR) and pre-extensively-resistant (pre-XDR) tuberculosis (TB) in migrants at two TB reference centers in Italy.

STUDY DESIGN

Patient selection criteria for the present study were as follows: age ≥18 years, international migrants (i.e., person who lives in a country other than his/her country of origin), MDR or pre-XDR-TB based on drug-susceptibility test findings, full availability of microbiological, radiological and clinical data. Non-intersecting populations between the two centers were selected. The primary outcome was the proportion of patients with a successful (i.e., cured and treatment completed) treatment outcome.

METHODS

A retrospective cross-sectional study was conducted, from 01/Jan/2000 to 01/Jan/2015, at the Regional TB Reference Centre of Lombardy Region, Villa Marelli Institute/ASST Niguarda Ca' Granda (Milan, Italy) and at the Reference Center for MDR-TB and HIV-TB, Eugenio Morelli Hospital ASST (Sondalo, Italy). All data were made anonymous. Qualitative and quantitative variables were collected in an ad hoc electronic database. The statistical software used for all computations was STATA version 15 (StataCorp, Texas, USA).

RESULTS

Overall, 116 MDR-TB and pre-XDR-TB cases were recorded: 82 (70.7%) MDR-TB and 34 (29.3%) pre-XDR-TB patients, respectively. The majority (53.5%) were from the World Health Organization European Region (excluding EU/EEA) and 75 (64.5%) were male. Median (interquartile range) age was 32 (26-39) years. TB/HIV coinfection was found in 12 (10.3%) patients. Pulmonary TB was diagnosed in 107/116 (92.2%) patients. Resistance to fluoroquinolones and second-line injectables was detected in 22/116 (19.0%) and 12/107 (11.2%) patients, respectively. Overall treatment success was reached in 95/116 (81.9%) cases.

CONCLUSION

Pre-XDR-TB in migrants coming from high-endemic countries represents a matter of concern; therefore, prevention and control activities targeted to high-risk populations are needed to progress toward TB elimination.

Towards tailored regimens in the treatment of drug-resistant tuberculosis: a retrospective study in two Italian reference Centres

Background

The increased incidence of drug-resistant TB is a major challenge for effective TB control. Limited therapeutic options and poor treatment outcomes of DR-TB may increase drug-resistance rates. The objective of the study is to retrospectively compare MDR-TB and pre-XDR-TB treatment regimens and outcomes in two large TB reference centres in Italy from January 2000 to January 2015.

Methods

A retrospective, multicentre study was conducted at the Regional TB Reference Centre Villa Marelli Institute (Milan) and at the Reference Center for MDR-TB and HIV-TB, Eugenio Morelli Hospital (Sondalo). The supra-national Reference Laboratory in Milan performed DST. Inclusion criteria were: age ≥ 18 and culture-confirmed diagnosis of MDR- or pre-XDR TB. Chi-square or Fisher exact test was used to detect differences in the comparison between treatment outcomes, therapeutic regimens, and drug-resistances. Computations were performed with STATA 15.

Results

A total of 134 patients were selected. Median (IQR) age at admission was 33 (26–41) years and 90 patients (67.2%) were male. Pulmonary TB was diagnosed in 124 (92.5%) patients. MDR- and pre-XDR-TB cases were 91 (67.9%) and 43 (32.1%), respectively. The WHO shorter MDR-TB regimen could have been prescribed in 16/84 (19.1%) patients. Treatment success was not statistically different between MDR- and pre-XDR-TB (81.3% VS. 81.4%; P = 0.99). Mortality in MDR-TB and pre-XDR-TB groups was 4.4 and 9.3%, respectively (P = 0.2). Median duration of treatment was 18 months and a total of 110 different regimens were administered. Exposure to linezolid, meropenem, and amikacin was associated with a better outcome in both groups (P = 0.001, P < 0.001, and P = 0.004, respectively).

Conclusions

Tailored treatment regimens based on DST results can achieve successful outcomes in patients with pre-XDR-TB.

Treatment outcomes and relapses of pulmonary tuberculosis in Lazio, Italy, 1999-2001: a six-year follow-up study

OBJECTIVES

The aim of this study was to enhance tuberculosis (TB) treatment outcome monitoring by linking diverse surveillance systems and estimating treatment outcomes including relapse.

METHODS

Tuberculosis treatment was surveyed in the Lazio region (Italy) from 1999 to 2001; a six-year follow-up of notified cases was undertaken to detect relapses. The results were analyzed as a population-based case-control study comparing each unsuccessful outcome and relapse with eligible controls.

RESULTS

Of the 974 patients who entered the survey, 805 (82.6%) had complete treatment evaluations; 398 (49.4%) had a successful outcome, 401 (49.8%) had an unsuccessful outcome, and six developed chronic TB. Death was associated with age >64 years (OR 5.9; 95% CI 3.1-11.2), male gender (OR 2.1; 95% CI 1.0-4.4), and using second-line drugs (OR 2.3; 95% CI 1.0-5.4). Treatment failure was associated with previous treatment (OR 3.0; 95% CI 1.4-6.7) and being male, being foreign born (OR 6.6; 95% CI 2.1-21.2), receiving second-line drugs (OR 7.4; 95% CI 1.8-29.5), and receiving modified therapy (OR 5.1; 95% CI 1.7-14.9). Relapses after successful outcomes were detected in 5.5%, for which the strongest predictor was having extrapulmonary lesions (OR 22.8; 95% CI 1.8-287.3).

CONCLUSIONS

Linking our survey data to other surveillance systems improved the mortality estimates and detected a high rate of relapse. Having received previous treatment and being a foreigner were independent determinants of treatment failure, suggesting that both acquired and primary drug resistance affect TB patients in Lazio.

Use of genotype MTBDR assay for molecular detection of rifampin and isoniazid resistance in Mycobacterium tuberculosis clinical strains isolated in Italy

Mycobacterium tuberculosis is one of the leading causes of death worldwide, and multidrug-resistant tuberculosis (MDR-TB) is associated with a high case fatality rate. Rapid identification of resistant strains is crucial for the early administration of appropriate therapy, for prevention of development of further resistance, and to curtail the spread of MDR strains. The Genotype MTBDR (Hain Lifescience, Nehren, Germany) is a reverse hybridization line probe assay designed for the rapid detection of rpoB and katG gene mutations in clinical isolates. The ability of this technique to correctly identify resistant and MDR-TB strains was tested on 206 isolates from the Italian drug resistance surveillance system. This panel included the majority of MDR strains isolated in Italy in the past 3 years. The results of the test were compared to conventional drug susceptibility test performed on isolated strains and verified by sequencing the regions of interest of the bacterial genome. The rate of concordance between the results of the MTBDR and those obtained with "in vitro" sensitivity was 91.5% (130 of 142) for rifampin and 67.1% (116 of 173) for isoniazid. We also applied this test directly to a panel of 36 clinical specimens collected from patients with active TB. The MTBDR correctly identified the two cases of MDR-TB included in the panel. These results show that the MTBDR test is useful in the detection and management of tuberculosis when MDR disease is suspected.

Long-term moxifloxacin in complicated tuberculosis patients with adverse reactions or resistance to first line drugs

STUDY OBJECTIVES

To test safety and tolerability of long-term moxifloxacin in resistant tuberculosis (TB) patients and patients with intolerance to first line anti-TB drugs.

DESIGN

Clinical evaluation of adverse events (AEs) during prolonged moxifloxacin treatment.

SETTING

TB Unit of the Regional TB Reference Center, Villa Marelli Institute, Niguarda Ca'Granda Hospital, Milan, Italy

PATIENTS AND INTERVENTIONS

Patients treated with moxifloxacin, 400 mg orally once daily for TB in the Villa Marelli Institute from January 2001 to December 2003 were enrolled.

RESULTS

Thirty-eight patients were treated with moxifloxacin at the Villa Marelli Institute in the study period, for multidrug resistant (MDR) TB (14, 36.8%), for intolerance to first line anti-TB drugs (9, 23.7%), for combined resistance and intolerance to first line anti-TB drugs (12, 31.6%), other reasons (3, 7.9%). The mean duration of moxifloxacin treatment was 6.3 +/- 5.2 months. Twelve (31.6%) patients reported at least an AE due to moxifloxacin, mostly gastrointestinal (8, 21.0%), general (5, 13.2%) and central nervous system (3, 7.9%) AEs. In 4 (10.5%) patients the drug was withdrawn for major AEs; no irreversible or fatal events were recorded. Most of the patients (31, 81.6%) reported a treatment success, even if the success rate was lower in MDR TB patients (8/14, 51.7%).

CONCLUSIONS

Despite the fact that a large proportion of patients experienced at least an AE due to moxifloxacin, the drug resulted safe in the long-term administration for complicated TB cases.

Risk factors for multidrug resistant tuberculosis in Europe: a systematic review

BACKGROUND

The resurgence of tuberculosis (TB) in western countries has been attributed to the HIV epidemic, immigration, and drug resistance. Multidrug resistant tuberculosis (MDR-TB) is caused by the transmission of multidrug resistant Mycobacterium tuberculosis strains in new cases, or by the selection of single drug resistant strains induced by previous treatment. The aim of this report is to determine risk factors for MDR-TB in Europe.

METHODS

A systematic review was conducted of published reports of risk factors associated with MDR-TB in Europe. Meta-analysis, meta-regression, and sub-grouping were used to pool risk estimates of MDR-TB and to analyse associations with age, sex, immigrant status, HIV status, occurrence year, study design, and area of Europe.

RESULTS

Twenty nine papers were eligible for the review from 123 identified in the search. The pooled risk of MDR-TB was 10.23 times higher in previously treated than in never treated cases, with wide heterogeneity between studies. Study design and geographical area were associated with MDR-TB risk estimates in previously treated patients; the risk estimates were higher in cohort studies carried out in western Europe (RR 12.63; 95% CI 8.20 to 19.45) than in eastern Europe (RR 8.53; 95% CI 6.57 to 11.06). National estimates were possible for six countries. MDR-TB cases were more likely to be foreign born (odds ratio (OR) 2.46; 95% CI 1.86 to 3.24), younger than 65 years (OR 2.53; 95% CI 1.74 to 4.83), male (OR 1.38; 95% CI 1.16 to 1.65), and HIV positive (OR 3.52; 95% CI 2.48 to 5.01).

CONCLUSIONS

Previous treatment was the strongest determinant of MDR-TB in Europe. Detailed study of the reasons for inadequate treatment could improve control strategies. The risk of MDR-TB in foreign born people needs to be re-evaluated, taking into account any previous treatment.

Mycobacterium lentiflavum infection in immunocompetent patient

Mycobacterium lentiflavum is a recently described nontuberculous mycobacterium that has mainly clinical importance in young children with cervical lymphadenitis and in immunocompromised patients. We describe a case of chronic pulmonary infection in an immunocompetent patient. Our observation confirms clinical, diagnostic, and treatment difficulties in the management of M. lentiflavum infection.