Volume 21, Number 6—June 2015
CME ACTIVITY - Research
Acquired Drug Resistance in Mycobacterium tuberculosis and Poor Outcomes among Patients with Multidrug-Resistant Tuberculosis
, Maia Kipiani, Veriko Mirtskhulava, Nestani Tukvadze, Matthew J. Magee, and Henry M. Blumberg
Table 1
Characteristics of patients with multidrug-resistant tuberculosis stratified by acquired resistance to second-line drugs, Georgia, March 2009–October 2012*
| Characteristic | Overall, n = 141 | Acquired resistance to second-line drugs |
p value† | |
|---|---|---|---|---|
| Yes, n = 19 | No, n = 122 | |||
| Median age, y (IQR) | 34.9 (27–46) | 41.4 (30–53) | 37.3 (27–45) | 0.28 |
| Male sex | 103 (73) | 16 (84) | 87 (71) | 0.24 |
| Married | 73 (52) | 10 (53) | 63 (52) | 0.94 |
| Employed | 19 (14) | 1 (5) | 18 (15) | 0.26 |
| History of imprisonment | 40 (28) | 6 (32) | 34 (28) | 0.74 |
| Diabetes mellitus | 16 (11) | 1 (5) | 15 (12) | 0.37 |
| Hepatitis C | 16 (11) | 3 (16) | 13 (11) | 0.51 |
| HIV positive | 6 (4) | 1 (5) | 5 (4) | 0.82 |
| Median BMI, kg/m2 (IQR) | 20.5 (2.7) | 20.0 (17.5–21.1) | 20.2 (18.9–22.5) | 0.049 |
| BMI ≤18.5 kg/m2 | 35 (25) | 7 (37) | 28 (23) | 0.19 |
| History of TB | 62 (44) | 10 (53) | 52 (43) | 0.41 |
| Prior TB treatment | 0.27 | |||
| None | 79 (56) | 9 (47) | 70 (57) | NA |
| First-line | 52 (37) | 7 (37) | 45 (37) | NA |
| Second-line | 10 (7) | 3 (16) | 7 (6) | NA |
| Baseline cavitary disease | 30 (21) | 11 (58) | 19 (16) | <0.01 |
| Median no. drugs to which baseline isolate was resistant (IQR) | 5 (5–6) | 6 (5–7) | 5 (5–6)] | 0.02 |
| Resistant to ≥6 drugs on baseline DST | 60 (43) | 14 (74) | 46 (38) | <0.01 |
| Baseline drug resistance category | ||||
| MDR only | 85 (60) | 8 (42) | 77 (63) | 0.01 |
| MDR + ofloxacin resistant | 9 (6) | 4 (21) | 5 (4) | NA |
| MDR + capreomycin or kananmycin resistant | 47 (33) | 7 (37) | 40 (33) | NA |
| Initial treatment inpatient | 45 (32) | 9 (47) | 36 (30) | 0.12 |
| Starting SLDs >30 days after TB diagnosis | 66 (47) | 6 (32) | 60 (49) | 0.15 |
| Median known active drugs in initial regimen (IQR)‡ | 3 (2–3) | 2 (1–3) | 3 (2–4) | 0.05 |
| Initial MDR TB treatment | ||||
| Pyrazinamide | 139 (99) | 19 (100) | 120 (98) | 0.57 |
| Prothionamide | 141 (100) | 19 (100) | 122 (100) | 1.00 |
| Capreomycin | 65 (46) | 13 (68) | 52 (43) | 0.04 |
| Kanamycin | 82 (58) | 6 (32) | 76 (62) | 0.01 |
| Levofloxacin | 134 (95) | 18 (94) | 116 (95) | 0.95 |
| Cycloserine | 135 (96) | 19 (100) | 116 (95) | 0.32 |
| p-aminosalicyclic acid | 140 (99) | 19 (100) | 121 (99) | 0.69 |
| Treatment interruption | 57 (40) | 12 (63) | 45 (37) | 0.03 |
| Baseline AFB sputum smear value >3+ | 46 (33) | 12 (63) | 34 (28) | <0.01 |
| Sputum culture positive, mo§ | ||||
| 2 | 121 (86) | 19 (100) | 102 (84) | 0.06 |
| 4 | 80 (57) | 17 (90) | 63 (52) | <0.01 |
| 6 | 48 (34) | 16 (84) | 32 (26) | <0.01 |
| Sputum smear positive, mo§ | ||||
| 2 | 115 (82) | 19 (100) | 96 (79) | 0.03 |
| 4 | 77 (55) | 17 (90) | 60 (49) | <0.01 |
| 6 | 39 (28) | 15 (79) | 24 (20) | <0.01 |
*Values are no. (%) unless otherwise indicated. IQR, interquartile range; BMI, body mass index; TB, tuberculosis; NA, not applicable; DST, drug susceptibility testing; MDR, multidrug resistant; SLDs, second-line drugs; AFB, acid-fast bacilli.
†Comparing persons with and without acquired resistance by using χ2 or Fischer exact tests for categorical variables and Wilcoxon-Mann-Whitney test for continuous variables.
‡DST was performed for streptomycin, isoniazid, rifampin, ethambutol, ofloxacin, ethionamide, kanamycin, capreomycin, and p-aminosalicyclic acid.
§Time from initiation of SLD treatment for MDR TB.