[Proposal of anti-tuberculosis regimens based on susceptibility to isoniazid and rifampicin].
OBJECTIVE
To elaborate optimal anti-tuberculosis regimens following drug susceptibility testing (DST) to isoniazid (H) and rifampicin (R).


METHODS
12 311 M. tuberculosis strains (National Health Institute of Peru 2007-2009) were classified in four groups according H and R resistance. In each group the sensitivity to ethambutol (E), pirazinamide (Z), streptomycin (S), kanamycin (Km), capreomycin (Cm), ciprofloxacin (Cfx), ethionamide (Eto), cicloserine (Cs) and p-amino salicilic acid (PAS) was determined. Based on resistance profiles, domestic costs, and following WHO guidelines, we elaborated and selected optimal putative regimens for each group. The potential efficacy (PE) variable was defined as the proportion of strains sensitive to at least three or four drugs for each regimen evaluated.


RESULTS
Selected regimes with the lowest cost, and highest PE of containing 3 and 4 effective drugs for TB sensitive to H and R were: HRZ (99,5%) and HREZ (99,1%), respectively; RZECfx (PE=98,9%) and RZECfxKm (PE=97,7%) for TB resistant to H; HZECfx (96,8%) and HZECfxKm (95,4%) for TB resistant to R; and EZCfxKmEtoCs (82.9%) for MDR-TB.


CONCLUSIONS
Based on resistance to H and R it was possible to select anti-tuberculosis regimens with high probability of success. This proposal is a feasible alternative to tackle tuberculosis in Peru where the access to rapid DST to H and R is improving progressively.
Instituto Nacional de Salud, Lima, Perú
Alberto
A
Mendoza-Ticona
David A J
DA
Moore
Valentina
V
Alarcón
Frine
F
Samalvides
Carlos
C
Seas
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000995:Antitubercular Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D002985:Clinical Protocols; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D007538:Isoniazid / Q000494:pharmacology* / Q000627:therapeutic use*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000187:drug effects*; D012293:Rifampin / Q000494:pharmacology* / Q000627:therapeutic use*; D014376:Tuberculosis / Q000188:drug therapy*; D055815:Young Adult
D000995:Antitubercular Agents; D007538:Isoniazid; D012293:Rifampin