Determinants of drug-resistant tuberculosis: analysis of 11 countries.

SETTING: Eleven countries/territories. OBJECTIVES: Global information on the determinants of drug-resistant tuberculosis (TB) based on representative data is not available. We therefore studied the relationship between demographic characteristics, prior TB treatment, and human immunodeficiency virus (HIV) infection with anti-tuberculosis drug resistance. METHODS: Population-based representative data on new and previously treated patients with TB collected within an international drug resistance surveillance network. RESULTS: Of 9,615 patients, 8,222 (85.5%) were new cases of TB and 1,393 (14.5%) were previously treated cases. Compared with new cases, previously treated cases were significantly more likely to have resistance to one (OR = 2.5,95% CI 2.1-3.0; P < 0.001), two (OR = 4.6, 95%CI 3.7-5.6; P < 0.001), three (OR = 11.5, 95%CI 8.6-15.3; P < 0.001), and four (OR = 18.5, 95% CI 12.0-28.5; P < 0.001) drugs. An approximately linear increase in the likelihood of having multidrug-resistant tuberculosis (MDR-TB) was observed as the total time (measured in months) of prior anti-tuberculosis treatment increased (P < 0.001, chi2 for trend). In multivariate analysis, prior TB treatment for 6-11 months (OR = 7.6, 95% CI 2.6, 22.4; P < 0.001) and > or = 12 months (OR 13.7, 95% CI 4.5-41.6; P < 0.001), but not HIV positivity, was associated with MDR-TB. CONCLUSION: This study shows that prior but ineffective treatment is a strong predictor of drug resistance, and that HIV is not an independent risk factor for MDR-TB. The association between length of treatment and drug resistance may reflect longer treatment as a result of treatment failure in patients with drug resistance; it may also reflect irregular prior treatment for TB, leading to drug resistance.     

Tolerability of anti-tuberculosis treatment and HIV serostatus.

SETTING: Tuberculosis (TB) is frequent in human immunodeficiency virus (HIV) infected patients, but its treatment is hampered by adverse events and paradoxical reactions. OBJECTIVE: To examine the impact of HIV infection and other factors on the risk and spectrum of adverse events related to anti-tuberculosis treatment in a prospective cohort study conducted between January 2003 and August 2004. RESULTS: Of 105 patients treated for TB, 30 were HIV-infected. The overall incidence of adverse events was 122.5 +/- 18.5 per 100 patient-years (py) and the incidence of severe adverse events was 45.2 +/- 11.3/100 py. Age >50 years (OR 2.2, 95%CI 1.01-4.8, P = 0.046) and HIV infection (OR 3.9, 95%CI 2.1-7.5, P < 0.001) were independently associated with a higher risk of adverse events. Hepatitis (30.5/100 py) and neuropathy (28.6/100 py) were the most frequent adverse events. Hepatitis C virus infection was associated with hepatitis (OR 4.2, 95%CI 1.2-15.0, P = 0.028) and neuropathy with HIV infection (OR 3.8, 95%CI 1.1-13.7, P = 0.040). CONCLUSION: Adverse reactions to anti-tuberculosis drugs are frequent. HIV infection and age >50 years are factors associated with such reactions, while hepatitis C virus infection is a risk factor for hepatitis.     

Risk factors for defaulting from tuberculosis treatment: a prospective cohort study of 301 cases in the Gambia.

SETTING: An urban tuberculosis (TB) clinic, The Gambia. OBJECTIVE: To identify patient characteristics associated with increased rates of defaulting from treatment, specifically knowledge and cost factors amenable to intervention. DESIGN: Prospective cohort study of TB cases at least 15 years of age commencing treatment, interviewed by semi-structured questionnaire and followed for attendance at thrice-weekly directly observed treatment (DOT). RESULTS: Of 301 patients, 76 (25.2%) defaulted from treatment and 25 did not return for treatment. The defaulting rate was higher among those who said they were uncertain that their treatment would work (HR 3.64; 95%CI 1.42-9.31, P = 0.007) and among those who incurred significant time or money costs travelling to receive treatment (HR 2.67; 95%CI 1.05-6.81; P = 0.04). These factors had differing effects with respect to time: uncertainty over treatment success was important in the first 90 days of treatment, while increased cost of travelling to the clinic was important after 90 days. CONCLUSION: In The Gambia, risk groups for defaulting can be recognised at the start of treatment and are at highest risk at different times. Home-based self-administration of medications after 3 months of DOT should be considered as confidence in treatment success rises, and the costs of travelling to receive treatment start to take their toll.     

Hepatotoxicity of tuberculosis chemotherapy under general programme conditions in Singapore.

SETTING: The Singapore Tuberculosis (TB) Control Unit, a high volume national referral centre. OBJECTIVES: To determine the incidence, clinical course and outcome of TB drug-induced hepatitis (DH) and the risk factors associated with DH under general programme conditions. DESIGN: A retrospective review of adult patients started on TB treatment in 1998. RESULTS: There were 55 cases of DH in the cohort of 1036 patients treated in 1998. The median time to diagnosis of DH was 38 days. Factors significantly associated with DH were abnormal baseline transaminases/ bilirubin (OR 2.1, 95%CI 1.1-4.3, P = 0.02), age >60 years (OR 1.97, 95%CI 1.14-3.34, P = 0.01) and female sex (OR 1.9, 95%CI 1.07-3.4, P = 0.02). Ethnicity, self-reported alcohol consumption and body weight were not associated with development of DH. All three patients with fatal DH had received pyrazinamide-containing regimens. Treatment was re-introduced in 48 patients and successfully completed in 45 patients. The median time to reinstitution of TB treatment was 23 days. CONCLUSION: The incidence of TB drug-induced hepatitis was 5.3%. Age >60 years, abnormal baseline transaminase/bilirubin levels and female sex were risk factors associated with the development of TB drug-induced hepatitis.     

HIV testing among tuberculosis patients in the era of antiretroviral therapy: a population-based study in Brazil.

SETTING: Rio de Janeiro, Brazil, a city with 29862 cases of tuberculosis (TB) reported between January 1995 and June 1998. OBJECTIVES: To evaluate the counseling and testing practices for human immunodeficiency virus (HIV) infection among TB patients, and to identify the patient characteristics associated with HIV screening as antiretroviral therapy was introduced. DESIGN: Cross-sectional study of patients with TB who were reported to the health department and who initiated anti-TB treatment. The main outcome measure was screened versus not screened for HIV. RESULTS: The proportion of TB patients who received HIV screening increased from January 1995 through June 1998 (P < 0.001). Among young adults aged 20-49 years with TB, the independent predictors of HIV screening were a diagnosis of both pulmonary and extrapulmonary TB (odds ratio [OR] = 2.4, 95% confidence interval [CI] 2.1-2.8); TB meningitis (OR = 13.5, 95%CI 6.5-31.5); disseminated TB (OR = 8.2, 95%CI 5.3-12.9); lymphatic TB (OR = 5.6, 95%CI 4.7-6.6); and male sex (OR = 1.4, 95%CI 1.3-1.6). Patients with newly diagnosed TB who were women, lived in a low income neighborhood (OR = 0.7, 95%CI, 0.6-0.7), and sought TB treatment in their own residential neighborhood (OR = 0.3, 95%CI 0.3-0.4) were less likely to receive HIV counseling and testing. CONCLUSION: Health care providers in Rio de Janeiro selectively offered HIV counseling and testing to persons they perceived to be at risk for HIV and those with advanced stages of TB. HIV counseling and testing should be expanded and offered to all TB patients.     

A population-based study of risk factors for drug-resistant TB in British Columbia.

SETTING: Provincial tuberculosis (TB) services, British Columbia, Canada. OBJECTIVE: To investigate risk factors associated with resistance to anti-tuberculosis drugs in British Columbia and to determine if there are differences in risk factor characteristics among different resistance categories. DESIGN: Using population-based data from provincial TB services, all patients with positive culture for Mycobacterium tuberculosis from 1990 to 2001 were identified and included in the study. Logistic regression analyses were performed to assess risk factors for drug resistance. RESULTS: Among 3041 eligible TB cases, 295 (10%) were found to be drug-resistant. Significant risk factors for resistance were younger age, foreign birth, ethnicity, reactivated TB and place of initial diagnosis. Foreign-born subjects (OR 3.18, 95%CI 2.26-4.49) were three times more likely to present with resistance than Canadian-born subjects. Among ethnic groups, Chinese (OR 2.32, 95%CI 1.51-3.57), South-East Asian (OR 2.92, 95%CI 1.88-4.52) and Other Asian subjects (OR 4.40, 95%CI 2.77-7.01) were 2-4 times more likely to present with resistance than Caucasians. Reactivated cases (OR 2.69, 95%CI 1.91-3.77) were three times as likely to have resistance as new cases. CONCLUSION: These results document and quantify the risk of drug-resistant disease in a large population-based cohort, and highlight patient groups who should be identified as at risk for drug-resistant disease in the industrialised world.     

Meta-analysis on the association of TIRAP S180L variant and tuberculosis susceptibility

The missense variant S180L in TIRAP (Toll-interleukin-1 receptor domain-containing adaptor protein) gene is implicated in attenuating TLRs signal transaction and may affect individual response to Mycobacterium tuberculosis infection. Several studies investigated the association between TIRAP S180L and risk of tuberculosis (TB), but the results were controversial. In this study, we quantitatively synthesized nine studies relevant to the association between TIRAP S180L polymorphism and TB risk with total 6584 TB cases and 7294 controls using meta-analysis. We found that the variant allele Leu180 and heterozygous genotype Ser/Leu were not significantly associated with risk of TB (allelic OR = 0.99, 95%CI: 0.88-1.11; Ser/Leu vs Ser/Ser: OR = 0.99, 95%CI: 0.87-1.13) with heterogeneity P values > 0.05. In subgroup analysis, none of the significant associations were observed for S180L and TB risk in Africans (allelic OR = 0.58, 95%CI: 0.29-1.61; heterozygous OR = 0.65, 95%CI: 0.32-1.32) or Asians (allelic OR = 1.30, 95%CI: 0.97-1.74; heterozygous OR = 1.17, 95%CI: 0.84-1.65) or risk of pulmonary tuberculosis (PTB) (allelic OR = 0.92, 95%CI: 0.69-1.22; heterozygous OR = 0.98, 95%CI: 0.86-1.12). This meta-analysis indicates that TIRAP S180L polymorphism is unlikely to substantially contribute to TB susceptibility.     

An epidemiological evaluation of risk factors for tuberculosis in South India: a matched case control study.

SETTING: There are limited data on risk factors associated with tuberculosis (TB) in India. OBJECTIVES: To evaluate potential socio-demographic risk factors for TB. DESIGN: Matched case-control. Cases were all new diagnoses of pulmonary TB attending as out-patients at St John's Medical College Hospital, Bangalore, India, from October 2001 to October 2003. Age- and sex-matched controls, one for each case (n = 189), were recruited among relatives accompanying non-TB in-patients in the hospital. RESULTS: Significant risk factors were low education level (OR 0.30; 95%CI 0.11-0.82), not having a separate kitchen (OR 3.26; 95%CI 1.25-8.46) and chronic disease, mainly diabetes (OR 2.44; 95%CI 1.17-5.09). High income, cooking with biomass fuels, history of smoking and alcohol consumption were not significant on multivariate analysis. Patients were respectively 11 and seven times more likely to have a BMI <18.5 (95%CI 5.62-21.98) and mid-arm circumference <24 cm (95%CI 3.87-11.89). CONCLUSIONS: In our study, TB was associated with low education level, kitchen type and diabetes, reflecting the complex interaction between non-communicable disease, urbanisation and a changing economic climate in Bangalore. The relationship between TB, the use of biomass cooking fuels and gender differentials related to fuel exposure merit further exploration. The study underscores the poor nutritional status of patients.     

Does antiretroviral treatment reduce case fatality among HIV-positive patients with tuberculosis in Malawi?

SETTING: Thyolo district, Malawi. OBJECTIVES: To report on 1) case fatality among human immunodeficiency virus (HIV) positive tuberculosis (TB) patients while on anti-tuberculosis treatment and 2) whether antiretroviral treatment (ART) initiated during the continuation phase of TB treatment reduces case fatality. DESIGN: Retrospective cohort analysis. METHODS: Comparative analysis of treatment outcomes for TB patients registered between January and December 2004. RESULTS: Of 983 newly registered TB patients receiving diagnostic HIV testing, 658 (67%) were HIV-positive. A total of 132 (20%) patients died during the 8-month course of anti-tuberculosis treatment, of whom 82 (62%) died within the first 2 months of treatment when ART was not provided (cumulative incidence 3.0, 95%CI 2.5-3.6 per 100 person-years). A total of 576 TB patients started the continuation phase of anti-tuberculosis treatment, 180 (31%) of whom were started on ART. The case-fatality rate per 100 person-years was not significantly different for patients on ART (1.0, 95%CI 0.6-1.7) and those without ART (1.2, 95%CI 0.9-1.7, adjusted hazard ratio 0.86, 95%CI 0.4-1.6, P = 0.6) CONCLUSIONS: ART provided in the continuation phase of TB treatment does not have a significant impact on reducing case fatality. Reasons for this and possible measures to reduce high case fatality in the initial phase of TB treatment are discussed.     

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.     

Defaulting from DOTS and its determinants in three districts of Arsi Zone in Ethiopia.

SETTING: Three districts of Oromia Region in Arzi Zone, Ethiopia. OBJECTIVES: To determine the rate of defaulting from directly observed treatment, short course (DOTS) for tuberculosis and identify associated factors. DESIGN: A case control study. Records of 1367 new tuberculosis patients put on DOTS during a period of 30 months (1 July 1997-31 December 1999) were reviewed to determine the defaulting rate. Cases were defaulters and controls were selected by paired matching of sex and age using the lottery method. All study subjects were actively traced and interviewed by trained interviewers using a pre-tested structured questionnaire. RESULTS: The overall rate of defaulting from DOTS was calculated to be 11.3%, while the rate in sputum smear-positive cases was 11.6%. Defaulting was highest (81%) during the continuation phase of treatment. Medication side effects were significantly associated with defaulting (OR = 4.20, 95% CI 1.51-11.66), while adequate knowledge and family support were found to be possible protective factors (OR = 0.04, 95% CI 0.02-0.1 and OR = 0.19, 95% CI 0.08-0.46, respectively). CONCLUSIONS: Major factors contributing to high rates of defaulting were found to be lack of family support, inadequate knowledge about treatment duration and medication side effects. Control programmes that take these factors into consideration should be successful in reducing defaulting.     

Adherence to anti-tuberculosis chemoprophylaxis and treatment in children.

SETTING: Limited data exist on adherence to anti-tuberculosis treatment and chemoprophylaxis in children in high-burden settings. OBJECTIVE: To determine the adherence to anti-tuberculosis chemoprophylaxis and treatment in children evaluated as household contacts of adult pulmonary tuberculosis (PTB) cases. METHODS: A retrospective study, conducted from January 1996 to September 2003, in suburban Cape Town, South Africa, with a high TB incidence. A folder search was done on all children <5 years of age identified as household contacts of adult PTB cases between 1996 and 2003. Data on screening for TB and adherence to prescribed therapy in child contacts were analysed. RESULTS: Three hundred and sixty-one contact episodes with 243 adult PTB cases were identified in 335 children. The median age was 25 months. Adherence to anti-tuberculosis treatment was significantly better than adherence to chemoprophylaxis (82.6% vs. 44.2%; OR 6.83; 95%CI 3.6-12.96). Adherence to a 3-month chemoprophylaxis regimen of isoniazid and rifampicin (3HR) was significantly better than adherence to a 6-month chemoprophylaxis regimen of isoniazid only (69.6% vs. 27.6%; OR 4.97; 95%CI 2.40-10.36). CONCLUSIONS: Although adherence to treatment was good, adherence to unsupervised chemoprophylaxis was poor. We recommend that shorter chemoprophylaxis regimens such as 3HR should be considered to improve adherence, but further studies are required.     

The risk of MDR-TB and polyresistant tuberculosis among the civilian population of Tomsk city, Siberia, 1999.

SETTING: Tomsk, Siberia, Russian Federation. OBJECTIVE: To evaluate the relationship between TB susceptibility patterns and risk factors among a civilian cohort of new cases in Tomsk city in 1999. DESIGN: Population-based study. The association between MDR-TB or PROMDR-TB, defined as resistance to isoniazid and rifampicin (MDR) or to isoniazid, ethambutol, and streptomycin (rifampicin mono-sensitive), and hypothesized risk factors was determined. Univariable analysis with and without stratification for history of incarceration and stepwise logistic regression modeling were used. RESULTS: Overall, 49.6% of participants were infected with a Mycobacterium tuberculosis strain resistant to at least one prescribed anti-tuberculosis medication. PROMDR-TB and MDR-TB were prevalent in 17.2% and 13.1% of participants, respectively. Logistic regression modeling indicated that good residence (OR 3.1, 95%CI 1.4-6.9), treatment default (OR 4.4, 95%CI 2.1-9.3) and psychological disorder (OR 3.3, 95%CI 1.0-10.9) were associated with PROMDR-TB. Both good residence (OR 2.6, 95%CI 1.1-6.0) and treatment default (OR 5.3, 95%CI 2.4-11.6) were associated with MDR-TB. History of incarceration was not found to be significant. CONCLUSION: Our findings support the hypothesis that drug-resistant disease among the Tomsk city population is not directly linked to history of incarceration, nor is it an extension of drug resistance in prisons. Rather, drug resistance in the civil sector reflects problems specific to the sector itself.     

Predictors of development and outcome in patients with acute respiratory distress syndrome due to tuberculosis.

OBJECTIVE: To study the predictors of development and determinants of outcome in patients with acute respiratory distress syndrome (ARDS) due to tuberculosis (TB). METHODS: Retrospective case-control study of demographic, clinical and laboratory data of hospitalised adult patients with active TB. RESULTS: Of 2733 TB patients treated during 1980-2003, 29 (1.06%; 1.21 patients/year; mean age 31.6 +/- 10.9 years; 16 males) developed ARDS (cases). Seven had pulmonary TB and 22 had miliary TB (MTB); 298 (mean age 32.0 +/- 14.2 years; 110 males) who did not develop ARDS constituted controls. Presence of MTB (OR 4.6, 95%CI 1.2-17.8; P = 0.02), duration of illness beyond 30 days at presentation (OR 177.9, 95%CI 39-811.7; P < 0.001), absolute lymphocyte count < 1625/ mm3 (OR 4.5, 95%CI 1.1-19.3; P = 0.04) and serum ALT > 100 IU (OR 15.7, 95%CI 3.0-81.1, P < 0.001) were independent predictors of ARDS development. Twelve cases died (41.4%). Patients with APACHE II score >18; those with APACHE II score <18 in the presence of hyponatraemia and PaO2/FIO2 ratio <108.5 were likely to die. CONCLUSIONS: In patients with TB, prolonged illness, MTB, absolute lymphocytopaenia and elevated ALT are independently associated with ARDS development. APACHE II score, serum sodium and PaO2/FIO2 ratio are determinants of outcome.     

Risk factors for multidrug-resistant tuberculosis in Hong Kong

SETTING: Previous anti-tuberculosis treatment is a widely reported risk factor for multidrug-resistant tuberculosis (MDR-TB), whereas other risk factors are less well described. In Hong Kong, the clinical characteristics of MDR-TB have not been systematically evaluated. OBJECTIVE: To explore the risk factors for MDR-TB in Hong Kong. DESIGN: MDR-TB patients treated between 1999 and 2003 were compared with non-MDR-TB patients by stratification of previous anti-tuberculosis treatment. RESULTS: One hundred and fifty-six MDR-TB patients, including 93 with and 63 without a previous history of anti-tuberculosis treatment, were identified. Among the 322 non-MDR-TB controls, respectively 192 and 130 patients did and did not have a previous history of anti-tuberculosis treatment. Using logistic regression analysis, non-permanent residents (OR 6.85, 95%CI 1.38-34.09), frequent travel (OR 2.48, 95%CI 1.07-5.74) and younger age were found to be independent predictors of MDR-TB in previously treated patients, whereas living on financial assistance just failed to reach statistical significance (OR 2.75, 95%CI 0.98-7.68, P=0.05). In the treatment-na?ve group, despite significant differences in baseline characteristics among MDR-TB and non-MDR-TB patients, no independent predictor variables could be identified. CONCLUSION: In Hong Kong, non-permanent residents, frequent travel and young age were independent predictors of MDR-TB among previously treated patients.     

Risk factors associated with default among new pulmonary TB patients and social support in six Russian regions.

SETTING: Tuberculosis (TB) services in six Russian regions in which social support programmes for TB patients were implemented. OBJECTIVE: To identify risk factors for default and to evaluate possible impact of social support. METHODS: Retrospective study of new pulmonary smear-positive and smear-negative TB patients registered during the second and third quarters of the 2003. Data were analysed in a case-control study including default patients as cases and successfully treated patients as controls, using multivariate logistic regression modelling. RESULTS: A total of 1805 cases of pulmonary TB were enrolled. Default rates in the regions were 2.3-6.3%. On multivariate analysis, risk factors independently associated with default outcome included: unemployment (OR 4.44; 95%CI 2.23-8.86), alcohol abuse (OR 1.99; 95%CI 1.04-3.81), and homelessness (OR 3.49; 95%CI 1.25-9.77). Social support reduced the default outcome (OR 0.13; 95%CI 0.06-0.28), controlling for age, sex, region, residence and acid-fast bacilli (AFB) smear of sputum. CONCLUSION: Unemployment, alcohol abuse and homelessness were associated with increased default outcome among new TB patients, while social support for TB patients reduced default. Further prospective randomised studies are necessary to evaluate the impact and to determine the most cost-effective social support for improving treatment outcomes of TB in patients in Russia, especially among populations at risk of default.     

Impact of country of origin on drug-resistant tuberculosis among foreign-born persons in British Columbia.

SETTING: Provincial tuberculosis (TB) services, British Columbia, Canada. OBJECTIVES: To estimate the risk of drug resistance among foreign-born TB patients and to identify risk factors associated with drug resistance. DESIGN: Using the provincial TB database, we examined all culture-positive foreign-born TB patients for the years 1990-2001. The risk of having a drug-resistant isolate was estimated according to country and region of origin. RESULTS: Of 1940 foreign-born patients identified, 247 (12.7%, 95%CI 11.3-14.3) cases had isolates resistant to at least one of the first-line drugs, with 160 (8.3%) isolates showing monoresistance, 24 (1.2%) multidrug resistance (resistance to at least isoniazid and rifampin) and 63 (3.3%) polyresistance (resistance to two or more drugs, excluding MDR). Country-specific analysis showed that immigrants from Vietnam (adjusted OR 2.12, 95%CI 1.37-3.27) and the Philippines (adjusted OR 1.71, 95%CI 1.10-2.66) had a significantly higher risk of resistance than other immigrants. In addition, the risk was the highest for younger TB patients and patients with reactivated disease (adjusted OR 2.12, 95%CI 1.09-4.09). CONCLUSION: The risk of drug resistance was the highest among foreign-born patients from Vietnam and the Philippines. These findings should assist clinicians in prescribing and tailoring anti-tuberculosis regimens for immigrants more appropriately.     

Factors contributing to treatment success among tuberculosis patients: a prospective cohort study in Bangkok

SETTING: Chest Clinic, Ministry of Public Health and health care centres, Bangkok Metropolitan Administration. OBJECTIVE: To determine patient factors predicting successful tuberculosis (TB) treatment. DESIGN: A prospective cohort was conducted during May 2004 to November 2005. Newly diagnosed TB patients aged > or = 15 years were recruited after giving informed consent. Three sets of questionnaires were used to collect data from the patients three times. Data were also gathered from treatment cards. RESULTS: Of 1241 patients, 81.1% were successfully treated. Bivariate analysis indicated that patients' sex, education, occupation, level of knowledge about TB and adverse effects were associated with treatment success. Unconditional logistic regression analysis showed that females had a higher success rate than males (OR = 1.9, 95%CI 1.2-2.9). Patients with regular incomes had twice the likelihood of success of the unemployed (OR = 2.0, 95%CI 1.1-3.5). Patients with high knowledge levels were more likely to complete treatment (OR = 2.0, 95%CI 1.2-3.4), while those with adverse effects were less likely to adhere (OR = 0.6, 95%CI 0.4-0.9). CONCLUSION: The current low treatment success rate may be partly due to inadequate knowledge about TB among patients. Improvements in health education and early detection and management of adverse effects should be prioritised by the National Tuberculosis Programme.     

Tuberculosis risk among staff of a large public hospital in Kenya

SETTING: In sub-Saharan Africa, high rates of tuberculosis (TB) and human immunodeficiency virus (HIV) infection pose a serious threat for occupationally acquired TB among health care workers. OBJECTIVE: To identify factors associated with TB disease among staff of an 1800-bed hospital in Kenya. DESIGN: We calculated TB incidence among staff and conducted a case-control study where cases (n = 65) were staff diagnosed with TB and controls (n = 316) were randomly selected staff without recent TB. RESULTS: The annual incidence of TB from 2001 to 2005 ranged from 645 to 1115 per 100000 population. Factors associated with TB disease were additional daily hours spent in rooms with patients (adjusted odds ratio [aOR] 1.3, 95%CI 1.2-1.5), working in areas where TB patients received care (aOR 2.1, 95%CI 1.1-4.2), HIV infection (aOR 29.1, 95%CI 5.1-167) and living in a slum (aOR 4.7, 95%CI 1.8-12.5) or hospital-provided low-income housing (aOR 2.6, 95%CI 1.2-5.6). CONCLUSION: Hospital exposures were associated with TB disease among staff at this hospital regardless of their job designation, even after controlling for living conditions, suggesting transmission from patients. Health care facilities should improve infection control practices, provide quality occupational health services and encourage staff testing for HIV infection to address the TB burden in hospital staff.