Figure 1.

Treatment history of the patient. The patient was initially treated with standard regimen using isoniazid, rifampicin, ethambutol, and pyrazinamide when first diagnosed with MTB infection in February 2012. Pre-treatment strain was collected before the initiation of anti-TB treatment. In early March 2012, the use of isoniazid, rifampicin, and pyrazinamide was halted due to deranged liver function. The regimen was subsequently switched to ethambutol and levofloxacin. Administration of isoniazid, rifampicin was resumed in late March. However, the treatment regimen was changed again in mid-April as the pre-treatment strain was confirmed to be MDR-TB. A combination of ethambutol, levofloxacin, prothionamide, kanamycin, and para-aminosalicylic acid was therefore administered in mid-April. Kanamycin was replaced by cycloserine in late May 2012 as phenotypic drug susceptibility test showed that the pre-treatment strain was resistant to aminoglycosides. The post-treatment strain was subsequently collected in June 2012, which is 4 months after the initiation of anti-TB treatment.