Characterization of clinical isolates of Mycobacterium tuberculosis resistant to drugs and detection of RpoB mutation in multidrug-resistant tuberculosis in the Philippines.

SETTING: Retrospective study of Mycobacterium tuberculosis isolates at the STD/AIDS Cooperative Central Laboratory, Philippines. OBJECTIVE: To describe patterns of M. tuberculosis resistance against first-line anti-tuberculosis drugs, and to analyze the rpoB gene codon mutation of rifampicin (RMP) resistant isolates and correlate genotypic and phenotypic patterns. DESIGN: One hundred and sixty-four M. tuberculosis complex isolates were retrieved for phenotypic analysis; 89 were resistant to any anti-tuberculosis drug and 50 were RMP-resistant, whereas 48 were multidrug-resistant (MDR). Of these 48, only 33 were available for genotypic analysis of the rpoB gene. RESULTS: Most drug-resistant isolates were phenotypically resistant to isoniazid (INH) (93%), and the probability of an RMP-resistant isolate becoming MDR was 96%. In 33 MDR isolates, 13 types of mutations in nine independent codons were identified; the most frequently mutated codons were S531L (61%) and G510H (15%), which were present in 76% (25/33) of the isolates. S531L was noted in 85.7% of the RMP + INH + SM resistant isolates, while only 80% of the isolates with INH + RMP, EMB + SM resistance showed this mutation. CONCLUSION: The high probability of RMP isolates being MDR suggests that genetic analysis of RMP resistance is useful in detecting MDR-TB. Worldwide accumulation of findings on circulating MDR-TB strains provides indispensable information about the re-emergence of TB.     

Isoniazid- and rifampin-resistant tuberculosis in San Diego County, California, United States, 1993-2002.

SETTING: A local tuberculosis (TB) control program. OBJECTIVES: To measure trends in isoniazid (INH) and rifampin (RMP) resistance and identify associated factors. DESIGN: Retrospective review. RESULTS: Of 2883 isolates obtained from TB patients reported between 1993 and 2002, 287 (10%) were resistant to INH, 11 (< 1%) were resistant to RMP, and 40 (1%) were resistant to both (multidrug resistance [MDR]). There were no linear trends over time. Eighty-one per cent of patients with INH resistance and 85% with MDR were born outside the United States. Sixty-three per cent of patients with drug resistance and prior TB treatment were treated outside the US. INH resistance was associated with race/ethnicity and prior treatment, RMP resistance with human immunodeficiency virus (HIV) infection, and MDR with non-US birth and prior treatment. Patients with INH- and RMP-susceptible or INH-resistant TB had higher percentages of treatment completion and sputum culture conversion than patients with RMP-resistant or MDR-TB. CONCLUSIONS: INH and RMP resistance remained stable between 1993 and 2002. Because most patients with drug resistance were infected or initially treated outside the US, future reductions in drug resistance will depend not only on local and national efforts, but also on the success of global interventions.     

The national tuberculosis drug resistance survey in Cambodia, 2000-2001.

SETTING: Cambodia has a high incidence of tuberculosis (TB). Hospital-based DOTS was predominant throughout the country from 1994 to 2002. OBJECTIVES: To determine the prevalence of resistance to four major anti-tuberculosis drugs, isoniazid (INH), rifampicin (RMP), ethambutol (EMB) and streptomycin (SM), among new cases as a baseline before a new National Tuberculosis Programme strategy with decentralised ambulatory DOTS was widely implemented. DESIGN: A cluster sampling of TB diagnostic centres with probability proportional to the number of new cases in a diagnostic centre in 1999 was used. Intake of cases took place from October 2000 to April 2001. RESULTS: From 734 isolates collected, drug susceptibility test results were obtained for 638 new cases. The prevalence of resistance to any of four drugs was 10.1% (95%CI 7.7-13). Resistance to INH was 6.1% (95%CI 4.3-8.4) and resistance to RMP 0.6% (95%CI 0.2-1.6). No multidrug-resistant (MDR) case was found among the new cases (95%CI 0.0-0.6). Three of 96 previously treated cases had MDR (3.1%, 95%CI 1.0-9.0). CONCLUSION: The first survey indicates that the current prevalence of MDR is low. It is necessary to track resistance trends when restructuring a DOTS-based programme.     

Trend of anti-tuberculosis drug resistance in Korea, 1994-2004.

SETTING: The 245 health centres through which the National Tuberculosis Programme (NTP) is implemented in Korea and the TB Laboratory Network of the Korean National Tuberculosis Association. OBJECTIVE: To observe the trend of anti-tuberculosis drug resistance in Korea from 1994 to 2004 and possible related factors. DESIGN: All tuberculosis (TB) patients registered for treatment at the health centres for a given period were assessed. RESULTS: Of 2636 new smear-positive patients from the 2004 survey, 338 cases (12.8%, 95% confidence interval [CI] 11.5-14.1) showed resistance to any of the first-line drugs: 261 with isoniazid (INH) resistance (9.9%, 95%CI 8.8-11.0) and 71 with multidrug resistance (MDR) (2.7%, 95%CI 2.1-3.3). Compared with previous surveys, a statistically significant increase in MDR (P=0.00675), any drug resistance (P=0.03779), any INH resistance (P=0.00313) and any rifampicin resistance (P = 0.00176) has been observed among new cases since 1994. Any resistance to second-line drugs ranged from 0.1% (capreomycin) to 1.1% (para-aminosalicylic acid) among new cases and from 1.1% to 3.6% among retreatment cases. Resistance to kanamycin and ofloxacin was found in 1.4% and 2.6%, respectively, of new and previously treated MDR-TB cases. CONCLUSION: A statistically significant increase in drug resistance was noticed among new cases.     

Anti-tuberculosis drug resistance in patients with HIV and tuberculosis in South India.

SETTING: Tuberculosis Research Centre clinics at Chennai and Madurai, Tamil Nadu, South India. OBJECTIVES: To investigate the prevalence and pattern of drug resistance among patients with HIV and pulmonary tuberculosis (PTB). DESIGN: Prospective cohort study of HIV-positive patients with PTB between January 2001 and May 2003. Sputum mycobacterial culture and drug susceptibility testing were performed. RESULTS: A total of 204 patients with positive sputum cultures for Mycobacterium tuberculosis were included; 167 of them were new cases, and 37 had a history of previous anti-tuberculosis treatment for > 1 month. Among the former, resistance to isoniazid (INH) was observed in 22 (13%) and MDR-TB in 7 (4.2%). Reported resistance rates in this geographic area among new cases ranged from 15% to 28% for INH and 2.8% to 3.4% for MDR (INH + rifampicin [RMP]). In contrast, among HIV-positive patients with a history of previous treatment, resistance was found to INH in 10 (27%) and to RMP in 7 (18.9%), while MDR-TB was seen in 5 (13.5%) patients. CONCLUSION: Among new TB patients, MDR-TB is marginally higher in HIV-positive patients than in the non-HIV-infected population in this region. Standard treatment guidelines should be followed. Higher rates of drug resistance are observed among previously treated patients.     

Adverse drug reactions associated with first-line anti-tuberculosis drug regimens.

BACKGROUND: Standard treatment of active tuberculosis (TB) consists of isoniazid (INH), rifampin (RMP), pyrazinamide (PZA) and ethambutol (EMB). Although this regimen is effective in treating active TB, it is associated with many adverse drug reactions (ADRs) and poses a significant challenge to completion of treatment. OBJECTIVES: To examine the incidence of major ADRs and risk factors associated with first-line anti-tuberculosis medications. METHODS: This study evaluated patients receiving treatment for active TB from a population-based database (2000-2005). The nature of the ADRs, likelihood of association with the study medications and severity were evaluated. RESULTS: A total of 1061 patients received treatment, of whom 318 (30%) had at least one major ADR. The overall incidence of all major ADRs was 7.3 events per 100 person-months (95%CI 7.2-7.5): 23.3 (95%CI 23.0-23.7) when on all four first-line drugs, 13.6 (95%CI 13.3-14.0) when on RMP, INH and PZA, and 2.4 (95%CI 2.3-2.6) when on INH and RMP. Adjusted hazard ratio (HR) revealed that combination regimens containing PZA, females, subjects aged 35-59 and >or=60 years, baseline aspartate aminotransferase >or=80 U/l and drug resistance were associated with any major event. CONCLUSIONS: First-line anti-tuberculosis drugs are associated with significant ADRs. There are several risk factors associated with the development of ADRs, including exposure to regimens containing PZA.     

Pattern of mycobacterial resistance to four anti-tuberculosis drugs in pulmonary tuberculosis patients in the state of Qatar after the implementation of DOTS and a limited expatriate screening programme.

OBJECTIVE: To determine the resistance pattern of Mycobacterium tuberculosis to four anti-tuberculosis drugs in pulmonary tuberculosis patients in the State of Qatar after the implementation of DOTS and an expatriate screening programme on arrival. METHOD: A state-wide, population-based, retrospective analysis of all cases of pulmonary tuberculosis with positive M. tuberculosis culture reported to the Division of Public Health TB Unit from January 1996 to December 1998. M. tuberculosis sensitivity testing was done by the Bactec method for isoniazid (INH), rifampicin (RMP), streptomycin (SM) and ethambutol (EMB). The results were interpreted as a daily change of the growth index of test vials (with drug) compared with controls. RESULTS: There were 406 isolates with positive M. tuberculosis culture. Sixty-one (15%) were resistant to one or more of the four anti-tuberculosis drugs, of which 58 (95%) were from newly diagnosed cases (primary) and three (5%) were from previously treated cases (acquired). Primary resistance was as follows: any resistance 15%, INH 12.4%, RMP 2%, SM 5.2%, EMB 0.8% and multidrug resistance (MDR, resistance to INH and RMP at least) was found in 0.8%. Acquired resistance was as follows: any resistance 15%, INH 15%, RMP 5%, SM 5% and MDR 5%. CONCLUSION: The prevalence of resistance to four anti-tuberculosis drugs is strikingly low due to the limited expatriate screening programme (chest radiography) and implementation of DOTS. The four-drug regimen is recommended for the initial phase of therapy until the results of sensitivity testing are known.     

Surveillance of Mycobacterium tuberculosis drug resistance in Hong Kong, 1986-1999, after the implementation of directly observed treatment.

OBJECTIVE: To study changing trends in TB epidemiology with emphasis on drug resistance rates in various age groups from 1986-1999. DESIGN: Laboratory-based data on drug susceptibility testing against streptomycin (SM), isoniazid (NH), rifampicin (RMP) and ethambutol (EMB) had been collected continuously in a centralised TB laboratory in Hong Kong. Epidemiological parameters such as sex, age and drug resistance rates in new and retreatment cases were measured and analysed for longitudinal trends. RESULTS: Of 48 924 non-duplicate isolates from new TB cases, 7045 (14.4%) were resistant to one or more drugs, 5773 (11.8%) were resistant to SM and/or INH while 881 (1.8%) were multidrug-resistant (MDR-TB). Of 3857 isolates from retreatment patients, 1176 (30.5%) were resistant to one or more drugs, 616 (16.0%) were resistant to SM and/or [NH, and 467 (12.1%) were MDR-TB. For isolates from new cases, significant declines were observed in the resistance rates against any drug, SM alone, INH alone, SM+INH and INH+RMP. For retreatment isolates, significant declines were also observed in resistance to any drug and INH+RMP. In both new and retreatment cases, isolates from patients aged over 65 years showed significantly lower drug resistance (any drug and INH+RMP) compared with other age groups (16-34 years and 35-65 years). CONCLUSION: With successful implementation of DOTS over a 14-year period, laboratory-based surveillance data showed significant declines in drug resistance, including MDR-TB. This has occurred amidst demographic changes associated with a generally ageing population as well as highly mobile sectors that are in constant exchange with highly endemic areas.     

Rifampicin mono-resistant Mycobacterium tuberculosis in Bujumbura, Burundi: results of a drug resistance survey.

SETTING: Bujumbura, Burundi. OBJECTIVES: To determine resistance levels of Mycobacterium tuberculosis (TB) to the main anti-tuberculosis drugs after 11 years of a DOTS programme using a WHO-recommended partially intermittent 6-month rifampicin (RMP) first-line regimen and fixed-dose drug combinations (FDCs). DESIGN: Drug susceptibility testing of systematic samples of M. tuberculosis isolated from newly registered sputum smear-positive cases in the capital during a 15-month period (2002-2003). RESULTS: Of 496 strains from new cases, 16.1% showed resistance to any drug, 6.3% to isoniazid (INH), 2.0% to RMP (1.4% multidrug-resistant TB [MDR-TB]), 13.3% to streptomycin and 1.6% to ethambutol. Among 69 strains from previously treated cases, the prevalence of resistance was 30%, 19%, 15% (12% MDR-TB strains), 25% and 6%, respectively. CONCLUSION: Levels of drug resistance in Bujumbura are higher than average for Africa, despite long-term use of the DOTS strategy with FDCs and a ban on sales of TB drugs. Most worrying is the appearance of MDR-TB and RMP-resistant, INH-susceptible strains in new cases. Although a survey cannot prove that high HIV prevalence, elevated levels of resistance to some other drugs and irregular intake allowed acquisition of drug resistance, the effectiveness and safety of 6-month regimens with (partially) intermittent RMP throughout under such conditions should be investigated.     

Drug resistance among smear-positive tuberculosis patients in Ho Chi Minh City, Vietnam.

OBJECTIVES: To assess the pattern of drug resistance among smear-positive tuberculosis (TB) patients in an inner city area in Vietnam. METHODS: A random sample of patients diagnosed by the national TB programme (NTP) were offered HIV testing and submitted sputum for Mycobacterium tuberculosis drug sensitivity testing. RESULTS: Of 1433 isolates from new patients, 360 (25%) were resistant to isoniazid (INH), 57 (4.0%) to rifampicin (RMP), 421 (29%) to streptomycin (SM) and 28 (2.0%) to ethambutol. Among 401 previously treated patients, this was 218 (54%), 109 (27%), 217 (54%) and 26 (7%), respectively. Multidrug resistance (MDR) was observed in 55 (3.8%) new and 102 (25%) previously treated patients. RMP resistance was strongly associated with resistance to INH (OR 46) and INH plus SM (OR 91, P = 0.004). Prevalence of drug resistance tended to decrease with age. Neither any resistance nor MDR was significantly associated with HIV infection. CONCLUSIONS: In this inner city area, levels of drug resistance, in particular of MDR among previously treated patients, are high. This may be related to the use of NTP regimens in the context of highly prevalent combined SM and INH resistance which may favour acquisition of RMP resistance.     

Population-based surveillance of extensively drug-resistant tuberculosis in Shandong Province, China

To investigate the prevalence of extensively drug-resistant tuberculosis (XDR-TB) in Chinese populations, we analyzed the drug resistance profiles of 1787 Mycobacterium tuberculosis isolates through a population-based surveillance project in Shandong Province, China. We found 330 (18.5%; 95%CI 16.1-20.3) isolates resistant to ≥1 first-line drug and 65 (3.6%; 95%CI 2.9-4.6) multidrug-resistant (MDR) isolates, of which 13 (20.0%; 95%CI 11.9-31.4) were XDR; 47/65 MDR-TB isolates (70.8%; 95%CI 58.2-81.4) were resistant to fluoroquinolones. Our results indicate that inadequate application of second-line anti-tuberculosis drugs has caused increased prevalence of XDR-TB in certain Chinese populations.     

Drug-resistant tuberculosis in Yangon, Myanmar

The extent of drug resistant tuberculosis (TB) in the capital city of Myanmar, Yangon has not yet been reported. This study aimed to determine the proportion and pattern of drug resistance to first-line anti-TB drugs, among Mycobacterium tuberculosis complex isolates from sputum smear positive TB patients who attended National TB Programme Yangon centres in April-August and October-December 2002. Drug susceptibility was determined by the Mycobacteria Growth Indicator Tube manual system (Becton Dickinson, MD, USA). Of the 567 patients, sputum specimens from 447 (79%) had a positive culture. Of these, 357 isolates (80%) had a susceptibility test result. Isolates from 76 of 259 (29.3%) new patients and from 45 of 98 (45.9%) previously treated patients were resistant to at least 1 of the anti-TB drugs. Resistance to isoniazid (INH) (22.0% vs 40.8%: new vs previously treated patients) and to > or =2 drugs (17.8% vs 29.6%: new vs previously treated patients) was common. Multidrug- resistant TB (MDR-TB) among new and previously treated patients was 4.2% and 18.4%, respectively. INH-resistant (adjusted OR: 2.0, 95% CI 1.1-3.6) and MDR-TB (adjusted OR: 3.4, 95% CI 1.4-8.3) cases were more likely to have taken anti-TB drugs > or =1 month previously. Collectively, prevalence of MDR-TB and TB resistance to > or =2 drugs are not rare in Yangon.     

Molecular genetics of drug-resistant Mycobacterium tuberculosis isolates in Finland, 1995-2004

SETTING: Modern molecular methods help us to understand the transmission and epidemiology of Mycobacterium tuberculosis. OBJECTIVE: To analyse the molecular epidemiology of drug-resistant tuberculosis (TB), and to characterise isoniazid (INH) and rifampicin (RMP) resistance conferring mutations in Finland during 1995-2004. DESIGN: A total of 3959 new M. tuberculosis isolates underwent drug susceptibility testing; all phenotypically resistant isolates were genotyped by IS6110 restriction fragment length polymorphism and spoligotyping if necessary. INH- and/or RMP-resistant isolates were sequenced for their resistance associated genes, katG locus 315 and rpoB, respectively. RESULT: Of the 3959 isolates tested (92.4% of culture-positive cases), 183 (4.6%) were resistant to at least one first-line anti-tuberculosis drug; 14 (0.4%) isolates were multidrug-resistant. Thirty-seven (20.4%) resistant isolates belonged to 17 clusters, and the largest cluster included four isolates. The Beijing family genotype accounted for 8.8% (16 isolates) of all drug-resistant isolates. A Ser315Thr mutation in katG was found in 46.7% (56 isolates) of the INH-resistant isolates and rpoB was mutated in 85.7% (18 isolates) of the isolates resistant to RMP. CONCLUSION: Transmission of drug-resistant TB is rare in Finland, especially between indigenous and immigrant populations. Screening of mutations that confer INH and RMP resistance seems to be feasible if risk factors for multidrug resistance exist.     

Prevalence of primary multidrug resistance to anti-tuberculosis drugs in Pakistan.

SETTING: Pakistan ranks sixth in the world in terms of tuberculosis (TB) burden, with a World Health Organization estimated incidence of 181 per 100000, or 286000 new cases annually. Hospital-based data indicate a significant problem of multidrug-resistant TB (MDR-TB) in the country and highlight the need to assess its extent at community level. In this cross-sectional study, sputum samples from 742 untreated newly diagnosed pulmonary TB patients from all over the country were used. OBJECTIVE: To assess the prevalence of primary drug resistance in Pakistan. RESULTS: Of 672 culture-positive patients, 76 (11.3%) showed resistance to one or more drugs. Resistance to streptomycin (10 microg/ml) was found in 36 (5.4%) patients, isoniazid (INH) (1 microg/ml) in 51 (7.6%), rifampicin (RMP) (5 microg/ml) in 15 (2.2%), ethambutol (10 microg/ml) in 12 (1.8%) and pyrazinamide in 22 (3.3%) samples. Forty-six (6.8%) of the isolates tested were resistant to a single drug, 10 (1.5%) to two drugs, 12 (1.8%) to three drugs, and 6 (0.9%) to four drugs, while 2 (0.3%) isolates were resistant to all five first-line agents. Primary MDR-TB was 1.8% (n=12) (INH 1 microg/ml, RMP 5 microg/ml). CONCLUSION: The results of this study show a prevalence of primary MDR-TB in Pakistan of <2%, which needs to be addressed through an effective DOTS strategy.     

Drug-resistant tuberculosis and HIV in Ukraine: a threatening convergence of two epidemics?

OBJECTIVE: To investigate anti-tuberculosis (TB) drug resistance rates in Donetsk Oblast, Ukraine, and to explore the association between the epidemics of human immunodeficiency virus (HIV) and multidrug-resistant TB (MDR-TB). METHODS: All consecutive newly diagnosed and previously treated patients with sputum smear-positive TB presenting to all TB units in Donetsk Oblast over 12 months were invited to take part in the study. A total of 1293 and 203 patients with TB were tested for HIV and MDR-TB in the civilian and penitentiary sectors, respectively. RESULTS: Of those enrolled for the study, 307 were HIV-positive, 379 had MDR-TB, and 97 had MDR-TB and HIV co-infection. MDR-TB rates in the civilian sector were respectively 15.5% (95%CI 13.1-17.8) and 41.5% (95%CI 36.4-46.5) in newly diagnosed and previously treated TB patients. Among prisoners, MDR-TB rates were 21.8% (95%CI 12.4-31.2) in new cases and 52.8% (95%CI 43.9-61.7) in previously treated TB cases. HIV status was significantly associated with MDR-TB (OR 1.7, 95%CI 1.3-2.3). CONCLUSIONS: High MDR-TB rates and a positive association between MDR-TB and HIV epidemics were found in Donetsk Oblast. Urgent measures to improve HIV prevention, control of drug-resistant TB and collaboration between HIV and TB control activities need to be implemented without further delay.     

Surveillance of Mycobacterium tuberculosis drug resistance in France, 1995-1997. AZAY Mycobacteria Study Group.

OBJECTIVE: To measure the rate of primary and secondary drug resistance of Mycobacterium tuberculosis on an ongoing basis. DESIGN: Data on all culture-positive tuberculosis were collected prospectively from 1995 through 1997 from a microbiological laboratory network of 19 university hospitals throughout France, and submitted quarterly to the National Reference Centre for Surveillance of Mycobacterial Diseases. RESULTS: A total of 2998 patients were included in the study. Among the 2333 (78%) previously untreated patients, 8.6% had isolates resistant to any drug, 4.8% to streptomycin (SM) alone, 1.2% to isoniazid (INH) alone, 1.8% to SM + INH, and 0.3% to INH + rifampicin (RMP) or multidrug resistance (MDR). Foreign birth was independently associated with a higher risk of primary resistance to any drug (odds ratio [OR] 1.5). Among the 268 (9%) previously treated patients, 20.9% had isolates resistant to any drug, 6.3% to SM alone, 3.4% to INH alone, 4.1% to SM + INH, and 3.7% to INH + RMP. Foreign birth (OR = 2.3), and human immunodeficiency virus positive status (OR = 4.4) were independently associated with a higher risk of secondary resistance to any drug. CONCLUSION: During the last 30 years there has been no increase in resistance to any drug among previously untreated patients. As expected, secondary resistance was highly associated with foreign birth. MDR-TB remains a rare event in France.     

Nationwide study of drug resistance among acid-fast bacilli positive pulmonary tuberculosis cases in Lebanon.

OBJECTIVE: To assess the prevalence of drug resistance among smear-positive sputum specimens from pulmonary tuberculosis (TB) cases in Lebanon. DESIGN: Between July 2002 and April 2004, 224 newly diagnosed TB cases and 21 previously treated TB cases were collected nationwide. Mycobacterium tuberculosis isolates were tested against isoniazid (INH), rifampicin (RMP), streptomycin (SM) and ethambutol (EMB) using the BACTEC-TB system. RESULTS: M. tuberculosis and non-tuberculous mycobacteria (NTM) isolates were recovered from 190 and 15 new cases, respectively, and from 16 and 1 previously treated cases, respectively. Overall drug resistance among new TB vs. previously treated TB cases was 19.5% and 75%, and for single drugs it was INH (12% vs. 63%), RMP (3% vs. 56%), SM (12% vs. 44%) and EMB (3% vs. 44%). The overall rate of multidrug resistance (MDR) was 5.8% (1% vs. 62.5%). The male:female ratio was 1.3:1; most were young adults. CONCLUSION: Relatively moderate single drug resistance and very low MDR rates were found among new TB cases, while among previously treated TB cases very high resistance and MDR resistance rates were detected. Such findings underline the need for ongoing stringent control measures to curb the spread of M. tuberculosis and its deleterious effects.     

Primary and acquired drug resistance in Polish tuberculosis patients: results of a study of the national drug resistance surveillance programme.

OBJECTIVE: To determine the prevalence and patterns of primary and acquired drug resistance among Mycobacterium tuberculosis isolates recovered from tuberculosis patients in Poland. DESIGN: In a prospective survey, M. tuberculosis strains were collected from 3970 tuberculosis patients (2976 newly diagnosed cases and 994 previously treated patients) bacteriologically confirmed by culture between November 1996 and October 1997. METHODS: Drug susceptibility testing to isoniazid (INH), streptomycin, ethambutol and rifampicin (RMP) was performed on L?wenstein-Jensen medium according to the proportion method and/or using the radiometric Bactec 460 TB system. RESULTS AND CONCLUSION: The male to female ratio was 2.61:1. The patients were aged between 6 and 82 years, with 86% of males and 77% of females aged over 35 years. Primary resistance to any drug was found in 3.6% of new patients; any INH resistance was 2.6%, any RMP resistance was 0.7%, and multidrug resistance (to INH and RMP [MDR]) was 0.6%. In previously treated cases, resistance to any drug was 17.0%, any INH resistance 14.1%, any RMP resistance 7.8%, and MDR 7.0%. Drug-resistant tuberculosis does not present a big problem in Poland; primary drug resistance has been monitored since 1960 with decreasing frequency, and rates remain at the same level as 20 years ago. Studies such as this should be conducted regularly to monitor drug resistance in Poland in order to effectively manage national tuberculosis control efforts.     

第四次全国结核病流行病学抽样调查--结核分支杆菌耐药性分析与评价

目的：分析我国结核分支杆菌耐药现状，为评价和指导国家结核病控制规划（NTP）提供基本数据，方法：对第四次全面流调的分离菌株进行6种抗结核药物（INH，SM，RFP，EMB，PAS－Na和TB1）的耐药性测定，结果：392株结核分支杆菌的总耐药率为27．8％，初始耐药率和获得性耐药率分别为18．6％和46．5％，耐多药率为10．7％，其中初始和获得性耐多药率分别为7．6％和17．1％；6种抗结核药物的耐药率由高到低分别为INH（17．6％），SM（17．3％），RFP（16．6％），PAS－Na(2.8%)，EMB（1．5％），和TB1（1．3％），耐1种，2种，3种和4种以上药物的初始耐药率和获得性耐药率分别为7．6％，4．6％，1．9％和14．7％，19．4％，10．1％和2．3％，不同性别，年龄组初始耐药差异无显著性。结论：本次流调的总耐药率，初始耐药率与第二次和第三次流调资料比较有显著性降低（P＜0．01），但仍处于较高水平，且耐药性的发生更趋向于这主要一线药物耐药和对多种药物耐药，尤其是MDR－TB发生率高，应引起重视。