Outcomes among tuberculosis patients with isoniazid resistance in Georgia, 2007–2009

Abstract

SUMMARY BACKGROUND The optimal management strategy for patients with isoniazid (INH) monoresistant forms of tuberculosis (TB) has been widely debated. The current daily 9-month regimen of rifampin, pyrazinamide and ethambutol was established based largely on trials in settings with low TB rates and low rates of drug resistance. OBJECTIVE To explore the outcomes of patients with INH-monoresistant TB in the country of Georgia, a setting with both high TB rates and drug-resistant forms of the disease. METHODS Retrospective record review of all patients diagnosed with smear-positive pulmonary TB resistant to either INH or INH+SM (streptomycin) in Georgia between 2007 and 2009. RESULTS Of 8752 patients with pulmonary TB registered in Georgia, 909 were found to have INH or INH+ SM resistance. Treatment outcomes were relatively poor in this group, with only 71% treatment success. Outcomes were significantly worse among patients with older age and a history of previous treatment. CONCLUSIONS INH or INH+SM resistance in pulmonary TB patients in Georgia is common. The low rates of treatment success suggest the need for an improved treatment regimen for patients with resistance to these first-line drugs; this need is particularly pronounced among the subset of patients with a history of previous treatment.

The impact of total antioxidant capacity on pulmonary function in asthma patients

“…Furthermore, the optimal regimen for the treatment of INH-resistant strains has not yet been determined, and the WHOrecommended 9-month RZE regimen was associated with poor outcomes in a recent large retrospective study in Georgia. 20,21 Since 2010, the WHO has recommended using HRE in the continuation phase of treatment among new cases in populations with known or suspected high levels of INH resistance. 22 Nonetheless, it remains unclear if these recommendations would also apply to settings with 10% primary INH resistance.…”

Treatment Outcomes with Fluoroquinolone-Containing Regimens for Isoniazid-Resistant Pulmonary Tuberculosis

“…The critical concentrations for all other drugs were determined as previously described (22,23). Resistance to INH was defined as resistance to INH alone or INH plus streptomycin, without resistance to other first-line anti-TB drugs (11,16).…”

“…Moreover, various individualized treatment regimens are widely used by attending clinicians, without sufficient clinical evidence (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Although the use of four or more effective drugs in the intensive phase and the use of at least three effective drugs during the continuation phase have been associated with fewer unfavorable outcomes (6), the currently recommended treatment regimen for INH-resistant TB usually consists of two or three effective drugs (7)(8)(9).…”

Evaluation of the Abbott RealTi m e MTB and RealTi m e MTB INH/RIF Assays for Direct Detection of Mycobacterium tuberculosis Complex and Resistance Markers in Respiratory and Extrapulmonary Specimens

“…Despite its outstanding design, ease of use, and almost fully automated system, it has two major weaknesses. First, it only detects the genetic markers of RIF resistance and completely ignores INH resistance, which is found in 5% to 15% of RIF-susceptible cases worldwide and has a significant impact on treatment outcome (12,13). Very few commercial assays, such as GenoType MTBDRplus (HAIN Lifescience, Nehren, Germany) or Anyplex plus MTB/NTM/MDR-TB (Seegene, Soul, South Korea), also allow for the detection of resistance markers for INH with sufficient reliability, although only the GenoType assays are widely used in high-prevalence countries (14,15).…”