Table 1. Criteria for drug-susceptibility testing referral per Peruvian National Tuberculosis Control Program guidelines*.
| A. Newly diagnosed smear- or culture-positive patients at risk for MDR TB. Persons were eligible for enrollment if they were 1) diagnosed with smear-positive pulmonary TB, 2) had no history of TB, and 3) had >1 of the following risk factors: |
| 1. Household contact of patient with documented MDR TB |
| 2. Household contact of patient in treatment with second-line drugs |
| 3. Household contact of patient who showed failure of TB therapy |
| 4. Household contact of patient who died of TB within the past 2 years |
| 5. HIV-positive by ELISA and Western blot confirmation |
| 6. Diabetes mellitus |
| 7. Health care worker, regardless of health care field, in the past 2 years |
| 8. Student of health sciences in the past 2 years |
| 9. Employee of the penitentiary system |
| 10. Chronic treatment with corticosteroids |
| 11. Other condition of immunosuppression |
| 12. Adverse reaction to TB medications requiring a change in regimen |
| 13. Hospitalization for any indication in the past 2 years lasting >15 days |
| B. Patients in whom first-line or second-line therapy may be failing. Persons were eligible for enrollment if they were 1) currently receiving first-line or second-line treatment, and 2) had a sputum sample collected after >2 months of treatment that was smear positive (i.e., monthly sputum collected between months 2 and 6) |
| C. Patients who had received >1 previous treatment and who did not have documented MDR TB. This included persons who: |
| 1. Abandoned any previous regimen and now presented for retreatment |
| 2. Relapsed after completion of any previous regimen within 6 months |
| 3. Unsuccessful treatment with any previous regimen |
| 4. Received multiple courses of TB treatment |
| 5. Had a history of private or auto-administered treatment |
| D. Newly diagnosed smear-negative patients at risk for smear-negative MDR TB. Persons were eligible for enrollment if they were 1) suspected to have active pulmonary TB, 2) were smear negative, 3) had no history of TB therapy, and 4) had >1 of the following risk factors: |
| 1. Pediatric household contact of patient with documented MDR TB |
| 2. Pediatric household contact of patient who died of tuberculosis within the past 2 years |
| 3. HIV positive by ELISA and Western blot confirmation |
*MDR, multidrug resistant; TB, tuberculosis.