INHA and tuberculosis: Following the assumption that high dose isoniazid may be effective in MTB strains with low-level isoniazid resistance due to mutations in the inhA promotor at positions 8, 15 or 16 (Domínguez et al., 2016), WHO guidelines proposed the high-dose isoniazid in the treatment of MDR/XDR-TB patients (World Health Organization, 2016).