Management of Extensively Drug-Resistant Tuberculosis in Peru: Cure Is Possible

Abstract

Aim To describe the incidence of extensive drug-resistant tuberculosis (XDR-TB) reported in the Peruvian National multidrug-resistant tuberculosis (MDR-TB) registry over a period of more than ten years and present the treatment outcomes for a cohort of these patients. Methods From the Peruvian MDR-TB registry we extracted all entries that were approved for second-line anti-TB treatment between January 1997 and June of 2007 and that had Drug Susceptibility Test (DST) results indicating resistance to both rifampicin and isoniazid (i.e. MDR-TB) in addition to results for at least one fluoroquinolone and one second-line injectable (amikacin, capreomycin and kanamycin). Results Of 1,989 confirmed MDR-TB cases with second-line DSTs, 119(6.0%) XDR-TB cases were detected between January 1997 and June of 2007. Lima and its metropolitan area account for 91% of cases, a distribution statistically similar to that of MDR-TB. A total of 43 XDR-TB cases were included in the cohort analysis, 37 of them received ITR. Of these, 17(46%) were cured, 8(22%) died and 11(30%) either failed or defaulted treatment. Of the 14 XDR-TB patients diagnosed as such before ITR treatment initiation, 10 (71%) were cured and the median conversion time was 2 months. Conclusion In the Peruvian context, with long experience in treating MDR-TB and low HIV burden, although the overall cure rate was poor, a large proportion of XDR-TB patients can be cured if DST to second-line drugs is performed early and treatment is delivered according to the WHO Guidelines.

Risk factors for extensively drug‐resistant tuberculosis: a review

“…XDR‐TB is more expensive and difficult to treat than MDR‐TB, and outcomes much worse with higher rates of treatment failure and death . These patients also presented longer duration until culture conversion, a median of 26 months or, accordingly to other series, a median of 183 days until conversion .…”

“…However, in many studies, no HIV‐positive patients were found . In one study, the population was specifically HIV‐negative .…”

“…XDR‐TB is more expensive and difficult to treat than MDR‐TB, and outcomes much worse with higher rates of treatment failure and death . These patients also presented longer duration until culture conversion, a median of 26 months or, accordingly to other series, a median of 183 days until conversion . Recent data showed that patients with XDR‐TB were 13 times more likely to remain culture‐positive at 6 months of treatment , reflecting the lack of effective drug schemes, and more frequently presenting a fatal outcome, with 23% of a series of patients dying during the first year of treatment .…”

Efflux as a mechanism for drug resistance inMycobacterium tuberculosis: Table 1

“…Patients with MDR-TB are treated following the recommendations of the WHO according to defined parameters (World Health Organization, 2010a). There are no official specific recommendations for the treatment of patients with XDR-TB, although positive experiences have been reported (Bonilla et al, 2008). Patients with XDR-TB have fewer options for treatment and risk higher mortalities, especially in HIV-coinfected persons, as has been reported earlier (Gandhi et al, 2006).…”

The Emergence of Extensively Drug‐Resistant Tuberculosis: A Global Health Crisis Requiring New Interventions: Part I: The Origins and Nature of the Problem

“…Recent reports address the treatment of XDR‐TB in nonoutbreak settings and where HIV infection is not a comorbidity 40–47 . The results are quite variable, no doubt due to the differences in severity of illness, rapidity of diagnosis, access to second‐line drugs, local expertise in TB treatment, adherence to therapy, sample size, issues related to referral bias, and, perhaps most importantly, the extent of drug resistance.…”