High early death rate in tuberculosis patients in Malawi.

SETTING: Thirty-eight district and mission hospitals in Malawi. OBJECTIVES: In patients registered with all types of tuberculosis (TB) in 1997 to determine 1) treatment outcomes, and 2) when in the course of anti-tuberculosis treatment TB deaths occurred. DESIGN: A retrospective study using information from TB registers, health centre registers, TB treatment cards and TB ward admission books. RESULTS: A total of 16,004 patients were registered with all types of TB, 6471 with smear-positive pulmonary tuberculosis (PTB), 5305 with smear-negative PTB and 4228 with extra-pulmonary tuberculosis (EPTB). Of patients with all types of TB, 3720 (23%) died: death rates were 22% in smear-positive PTB, 26% in smear-negative PTB and 22% in EPTB. Month of death was known in 3371 patients (91% of those who died) and day of death in 3326 patients (89% of those who died). In patients who died, 19% of deaths occurred by day 7 and 41% by the end of the first month of treatment. A higher proportion of early deaths occurred in patients with smear-negative PTB and EPTB and in relation to increasing age. CONCLUSIONS: There was a high overall death rate in TB patients registered in 1997, with 40% of deaths occurring in the first month of treatment. Strategies to combat this problem are needed.     

Risk factors for delay in the diagnosis and treatment of tuberculosis at a referral hospital in Rwanda.

SETTING: Kigali University Hospital, the main referral centre for TB in Rwanda. OBJECTIVE: To evaluate delays in the diagnosis and treatment of tuberculosis (TB) and associated risk factors. DESIGN: Prospective data collection of patients treated for pulmonary TB (PTB) or extra-pulmonary TB (EPTB) between June and September 2006. RESULTS: Of 104 patients with a mean age of 35 years (range 17-84) recruited into the study, 62% were HIV-positive. EPTB was diagnosed in 60 cases. The median total, health care and patient delays were respectively 57, 28 and 25 days. The health system delay before referral was significantly longer than the delay at our institution (18 vs. 6 days, P<0.0001). Risk factors for a longer health system delay at our institution were smear-negative PTB or EPTB (OR 5.12) and a trial of antibiotics (OR 2.96). The latter was also found to significantly prolong total delay (OR 2.85), as did rural residence (OR 4.86). No significant association was found between patient delay and age, sex, profession or health insurance status. CONCLUSION: Smear-negative PTB and EPTB were associated with longer health system delays. A trial of antibiotics significantly increased the health system delay. Its use, recommended by the World Health Organization in case of smear-negative TB and EPTB in developing countries, needs validation at the tertiary health care level.     

What causes smear-negative pulmonary tuberculosis in Malawi, an area of high HIV seroprevalence?

SETTING: The Central Hospital and the District Tuberculosis (TB) Registry in Lilongwe, the capital of Malawi. In this setting smear-negative pulmonary tuberculosis (PTB) is diagnosed using clinical and radiographic criteria for TB, and mycobacterial cultures are not routinely available. OBJECTIVE: To determine the proportion of patients being registered for smear-negative PTB treatment in Lilongwe who have TB that can be confirmed microbiologically. DESIGN: Prospective cohort study of patients about to start treatment under operational conditions for smear-negative PTB in Lilongwe between October 1997 and June 1998. Patients referred to the study team underwent a detailed clinical re-assessment, testing for human immunodeficiency virus (HIV), repeat sputum smear microscopy for acid-fast bacilli and mycobacterial cultures of sputum and blood. Bronchoscopy and bronchoalveolar lavage (BAL) were performed and BAL fluid was examined for TB, Pneumocystis carinii and other fungi. RESULTS: Of 352 smear-negative PTB suspects assessed, the diagnosis of TB was confirmed in 137 (39%) cases. Eighty-nine per cent of patients assessed were HIV-positive, of whom 81% met the expanded case definition for the acquired immune-deficiency syndrome (AIDS). CONCLUSION: TB was the most commonly confirmed diagnosis amongst patients about to start treatment for smear-negative PTB in an area of high background HIV seroprevalence.     

Diagnosing smear-negative tuberculosis using case definitions and treatment response in HIV-infected adults.

OBJECTIVE: To assess the diagnostic utility of expanded case definitions for HIV-associated smear-negative pulmonary tuberculosis (PTB) and extra-pulmonary TB (EPTB), and to derive objective criteria for response to anti-tuberculosis treatment. DESIGN: A prospective cohort study of HIV-infected adults who met expanded clinical case definitions for smear-negative PTB and EPTB. METHODS: All participants were started on rifampicin-based anti-tuberculosis treatment after mycobacterial cultures from multiple sites. At weeks 2, 4 and 8, response to treatment (RTT) was assessed by measuring changes in weight, haemoglobin, C-reactive protein, Karnofsky performance score and symptom count ratio. RESULTS: Of 147 participants enrolled, 105 (71%) were diagnosed with definite (culture-positive) or probable (histological features) TB and 25 (17%) with possible TB (treatment response). The positive predictive value for the most common case definitions ranged from 89% to 96%. Significant improvements in all the RTT parameters occurred in the subjects with confirmed TB (P < 0.001). Clinically relevant RTT criteria were derived, two or more of which were met at week 8 in 97.5% of subjects with confirmed TB, 91.3% of subjects with possible TB and none of the subjects without TB. CONCLUSION: Expanded case definitions could enhance the diagnosis of PTB and EPTB in HIV-infected adults in resource-limited settings. Using objective criteria, RTT can be assessed within 8 weeks of initiating anti-tuberculosis treatment.     

Extra-pulmonary manifestations in a large metropolitan area with a low incidence of tuberculosis.

BACKGROUND: The increases in extra-pulmonary tuberculosis (EPTB) have been largely due to human immunodeficiency virus co-infection. The rates of EPTB have remained constant despite the decline in pulmonary tuberculosis (PTB) cases. OBJECTIVE: To evaluate covariates associated with EPTB. METHODS: A 4-year cohort of EPTB patients was compared with PTB cases. Enrollees were assessed for TB risk, medical records were reviewed, and Mycobacterium tuberculosis isolates were fingerprinted. RESULTS: We identified 538 EPTB cases (28.6%) in a total of 1878 enrollees. The most common sites of infection were lymph nodes (43%) and pleura (23%). EPTB cases included 320 (59%) males, 382 (71%) patients were culture-positive, and 332 (86.9%) patient isolates were fingerprinted. Fewer EPTB than PTB patients belonged to clustered M. tuberculosis strains (58% vs. 65%; P = 0.02). A multivariate model identified an increased risk for EPTB among African Americans (OR = 1.9, P = 0.01), HIV-seropositive (OR = 3.1, P < 0.01), liver cirrhosis (OR = 2.3, P = 0.02), and age <18 years (OR = 2.0, P = 0.04). Patients with concomitant pulmonary and extra-pulmonary infections were more likely to die within 6 months of TB diagnosis (OR = 2.3, P < 0.01). CONCLUSIONS: African American ethnicity is an independent risk factor for EPTB. Mortality at 6 months is partly due to the dissemination of M. tuberculosis and the severity of the underlying co-morbidity.     

Evaluation of a unified treatment regimen for all new cases of tuberculosis using guardian-based supervision.

SETTING: Ntcheu District, Malawi, using an oral antituberculosis treatment regimen. OBJECTIVE: To determine whether directly observed treatment (DOT) during the initial phase of treatment supervised either in hospital, at health centres or by guardians in the community, was associated with 1) satisfactory 2-month and 8-month treatment outcomes, and 2) with a reduction of in-patient hospital-bed days. DESIGN: Prospective data collection of all tuberculosis (TB) patients registered between 1 April 1996 and 30 June 1997, with 2-month and 8-month treatment outcomes, sputum smear conversion in smear-positive pulmonary TB patients (PTB) and in-patient hospital-bed days. RESULTS: Among the 600 new patients, 302 had smear-positive PTB, 150 smear-negative PTB and 148 extrapulmonary TB (EPTB). Eight-month treatment completion was 65% for smear-positive PTB patients, which was significantly higher than in patients with smear-negative PTB (45%) and EPTB (54%), due mainly to high 8-month mortality rates. The site of the intensive phase was determined in 596 patients: 178 (30%) received DOT from guardians, 115 (19%) from a health centre and 303 (51%) in hospital. At 2 months, mortality rates were significantly higher in hospitalised patients. Two-month treatment outcomes (including sputum smear conversion rates in smear-positive PTB patients) were similar between patients receiving DOT at health centres or from guardians. Decentralised DOT resulted in a 25% reduction in hospital-bed days in patients alive at 2 months compared with that predicted using the old regimens. CONCLUSION: Decentralising DOT to health centres and to guardians during the intensive phase is associated with satisfactory treatment outcomes.     

The first-three year report of the Tuberculosis Control Project, Lumbini, Rupandehi

The Tuberculosis Control Project, Lumbini, Rupandehi (TCPLR) is a bilateral cooperative venture between two NGO's, the Nepal Anti-Tuberculosis Association (NATA) and the Japan Anti-Tuberculosis Association (JATA), which consists of planning and implementing pilot tuberculosis control activities in Lumbini, Rupandehi district in Nepal, aiming at achieving high cure rate of newly detected smear-positive pulmonary tuberculosis patients before introducing DOTS strategies. Between December 1993 and July 1996, 349 tuberculosis (TB) cases were enrolled in the TCPLR. The categories of cases were as follows: 138 cases (40%) of new smear-positive pulmonary TB [new Sm(+) PTB], and 54 cases (15%) of smear positive pulmonary TB other than new Sm(+) PTB [other Sm(+) PTB] including such cases as continued treatment and relapse, 106 cases (30%) of new smear-negative TB [new Sm(-) TB], and 51 cases (15%) of other smear-negative TB other than New Sm(-) PTB [other Sm(-) TB]. The number and proportion of new Sm(+) PTB cases enrolled in the project have been increasing [6 cases (23%) for the first year, 102 cases (54%) for the third year] although the proportion is still low (40% overall). The regimens of chemotherapy in the initial intensive and the continuation phases of treatment according to the categories of TB were as follows: New Sm(+) PTB; 2HRZE(S)/6HE, other Sm(+) PTB; 2HRZES/1HRZE/5HRE, and Sm(-) TB; 2HRZ/6HE. The proportion of cases treated by the appropriate regimen of chemotherapy has increased. The cohort analysis of the treatment outcome of the cases enrolled in the project showed the following. The proportion of cured cases plus smear-unconfirmed cases completing treatment among new Sm(+) PTB was 74% overall, however, the proportion of defaulters increased in the third year. The proportion of cured cases plus smear-unconfirmed cases completing treatment among other Sm(+) PTB cases was 66% overall, which is slightly lower than that of new Sm(+) PTB cases, however, the difference was not so marked. The proportion of treatment completed cases among smear-negative pulmonary TB cases was 77% overall, however, proportion of defaulters increased in the third year. The treatment outcome in this report was obtained before the adoption of DOTS strategies: However, it showed that cure and treatment completion rates were comparable to those obtained in the SEARO countries which adopt DOTS strategies. The treatment outcome could be improved after the introduction of DOTS strategies in 1997.     

Mortality rates and recurrent rates of tuberculosis in patients with smear-negative pulmonary tuberculosis and tuberculous pleural effusion who have completed treatment.

SETTING: Queen Elizabeth Central Hospital, Blantyre, and Zomba Central Hospital, Zomba, Malawi. OBJECTIVE: To follow-up human immunodeficiency virus (HIV) seropositive and HIV-seronegative patients with smear-negative pulmonary tuberculosis (PTB) and pleural TB who had completed treatment with two different regimens in Blantyre and Zomba, and to assess rates of mortality and recurrent TB. DESIGN: Patients with smear-negative and pleural TB who had completed 8 months ambulatory treatment in Blantyre or 12 months standard treatment in Zomba and who were smear and culture negative for acid-fast bacilli at the completion of treatment were actively followed every 4 months for a total of 20 months. RESULTS: Of 248 patients, 150 with smear-negative PTB and 98 with pleural TB, who completed treatment and were enrolled, 205 (83%) were HIV-positive. At 20 months, 145 (58%) patients were alive, 85 (34%) had died and 18 (7%) had transferred out of the district. The mortality rate was 25.7 per 100 person-years, with increased rates strongly associated with HIV infection and age >45 years. Forty-nine patients developed recurrent TB. The recurrence rate of TB was 16.1 per 100 person-years, with increased rates strongly associated with HIV infection, having smear-negative PTB and having received 'standard treatment'. CONCLUSION: High rates of mortality and recurrent TB were found in patients with smear-negative PTB and pleural effusion during 20 months of follow-up. TB programmes in sub-Saharan Africa must consider appropriate interventions, such as co-trimoxazole and secondary isoniazid prophylaxis, to reduce these adverse outcomes.     

Prospective study of SEVA TB peroxidase assay for cocktail antigen and antibody in the diagnosis of Tuberculosis in suspected patients attending a tertiary care hospital located in rural area

ObjectiveTo evaluate inhouse developed SEVA TB peroxidase enzyme immunoassay using cocktail of mycobacterial excretory-secretory antigens (ES-31, ES-43 & EST-6) for antibody detection and their affinity purified antibodies for antigen detection in tuberculosis suspected patients.MethodsInhouse developed SEVA TB peroxidase enzyme immunoassay was evaluated prospectively in 73 suspected pulmonary and 46 extra-pulmonary tuberculosis patients during November 2008～March 2009 in a tertiary hospital located in rural area.ResultsAssay on prospective analysis showed 100% correlation of pulmonary tuberculosis (PTB) and extra-pulmonary tuberculosis (EPTB) acid fast bacilli positivity and antitubercular treatment in 11 cases. Thirty nine PTB and 12 EPTB cases showed negative for ELISA test and were also not given antitubercular therapy. However 30 PTB and 27 EPTB cases showing ELISA positivity were neither acid fast bacilli positive nor antitubercular therapy treated. These cases may possibly have dormant infection and need further diagnosis. In EPTB cases ELISA was observed to be more useful than AFB smear test.ConclusionsThis inhouse developed user-friendly peroxidase ELISA can be used as an adjunct test of smear microscopy or culture techniques for routine screening of patients suspected of PTB or EPTB.     

Childhood tuberculosis in Malawi: nationwide case-finding and treatment outcomes.

SETTING: All 43 non-private hospitals (three central, 22 [corrected] district and 18 [corrected] mission) in Malawi that register and treat adult and paediatric TB cases. OBJECTIVE: To assess the rate, pattern and treatment outcome of childhood TB case notifications in Malawi in 1998. DESIGN: Retrospective data collection using TB registers, treatment cards and information from health centre registers. Information was collected on number of cases, types of TB and treatment outcomes using standardised definitions. RESULTS: There were 22,982 cases of TB registered in Malawi in 1998, of whom 2,739 (11.9%) were children. Children accounted for 1.3% of all case notifications with smear-positive pulmonary TB (PTB), 21.3% with smear-negative PTB and 15.9% with extra-pulmonary TB (EPTB). Estimated rates of TB in children were 78/ 100,000 in those aged less than one year, 83/100,000 in those aged 1-4 years and 33/100,000 in those aged 5-14 years. A significantly higher proportion of TB cases was diagnosed in central hospitals. Only 45% of children completed treatment. There were high rates of death (17%), default (13%) and unknown treatment outcomes (21%). Treatment outcomes were worse in younger children and in children with smear-negative PTB. Treatment completion was best (76%) and death rates lowest (11%) for the 127 children with smear-positive PTB. CONCLUSION: Childhood TB is common in Malawi and treatment outcomes are poor. Research should be directed towards improved diagnosis and follow-up of children with TB, and the National TB Programme should support appropriate management of childhood contacts of smear positive PTB cases.     

全国初治涂阴肺结核病例登记现状分析

目的分析全国各省初治涂阴肺结核病例登记现状,为评价初治涂阴肺结核病例诊断质量提供依据。方法根据2004—2005年全国结核病防治规划报表中初治涂阴和初治涂阳肺结核病例登记资料,分析各省2年初治涂阴肺结核病例登记率变化和增长幅度;统计各省及不同地区初治涂阴与初治涂阳肺结核病例登记率;对各省初治涂阴与初治涂阳肺结核病例登记率进行直线回归分析。结果2005年全国登记初治涂阴肺结核病例316 405例,登记率为24.27/10万,各省登记率在6.01/10万72.17/10万;2005年登记初治涂阴病例数比2004年增加了19.9%,其中2个省登记数呈负增长,其余各省登记数增长了0.5%62.3%;2005年全国初治涂阳病例登记率是涂阴病例登记率的1.5倍,其中23个省初治涂阳病例登记率高于涂阴病例登记率,8个省相反;初治涂阴病例占初治涂阳病人登记率的比例,京津沪地区为149.28%,非项目地区为83.6%,项目地区为50.3%;对涂阳和涂阴病例登记率进行直线回归分析,回归方程y=22.342+0.563 6x。结论对初治涂阴肺结核患者实行免费政策后,全国涂阴肺结核病例登记率提高。但各省初治涂阴病例登记率和增长幅度以及涂阴病例登记率与涂阳病例登记率的比例悬殊。由于涂阴病例诊断困难,对于涂阴病例登记率高或增长幅度大的地区,特别在DOTS执行时间短和人力资源有限的地区,应对涂阴病例诊断质量予以进一步检查和评价。     

Comparison of extra-pulmonary and pulmonary tuberculosis cases: factors influencing the site of reactivation.

SETTING: Mycobacterium tuberculosis bacilli spread by the hematogenous route during primary infection and reactivate later. OBJECTIVE: To compare factors influencing the reactivation site. DESIGN: A total of 236 pulmonary tuberculosis (PTB) and 139 extra-pulmonary TB (EPTB) cases were compared in terms of age, co-morbid disease, immunosuppressive drug use, history of contact with a PTB case in a close relative, history of tuberculosis, smoking habit and alcohol intake. RESULTS: The sex ratio of EPTB and PTB cases was significantly different (P < 0.001): respectively 74% of EPTB cases and 34% of PTB cases were females; 53.3% of PTB cases and 23% of EPTB cases were smokers (P < 0.001); and the disease appeared within the first 5 years after contact in 23.7% of EPTB cases compared to 72.6% in PTB cases (P < 0.001). In logistic regression analysis, gender (OR = 3.69), smoking habit (OR = 0.54) and interval between contact and disease (OR = 1.07) were found to influence the reactivation site. CONCLUSION: The probability of PTB development was higher in males, in smokers and within the first 5 years of contact. In contrast, the probability of EPTB development was higher in females and after 5 years of contact.     

The role of induced sputum in the diagnosis of pulmonary tuberculosis

OBJECTIVES: To determine the sensitivity of referral guidelines for induced sputum in pulmonary tuberculosis (PTB) case detection and determine the diagnostic yield of the test. METHODS: A retrospective analysis of case notes of adult patients referred for induced sputum was carried out at the North Trent Regional Department of Infection and Tropical Medicine, the Royal Hallamshire Hospital, Sheffield, UK. Clinical characteristics were noted on patients referred during a 12-month period in 2001-2002, and of all patients with positive induced sputum results from April 1998 to March 2002. RESULTS: Over a 12-month period 114 patients were referred in our unit for induced sputum sampling. Twelve of the 114 patients had positive sputum cultures giving a positive yield for the test of 10.5%. With strict adherence to our referral guidelines, 10 of the 12 positive cases (83.3%) would have been detected. With modification to the referral guidelines, all 12 microbiologically positive cases would have been detected making the guidelines 100% sensitive in detecting microbiologically positive cases among patients referred with a clinical suspicion of PTB who are unable to self-expectorate. The positive yield for the test would have been increased to 13.2%. In the past 4 years 29 patients had positive induced sputum results. Of these, 11 patients (37.9%) had concurrent microbiological proven extra-pulmonary TB (EPTB) and 10 (34.5%) had past histories of TB infection. Seven patients had chest X-rays reported as normal. CONCLUSIONS: Induced sputum offers a relatively non-invasive investigation for patients with suspected PTB who are unable to bring up sputum. Induced sputum also offers a means of establishing a microbiological diagnosis in some cases of EPTB. An investigative algorithm is suggested.Summary. In an era of increasing drug resistant disease, establishing a microbiological diagnosis of TB is paramount. Sputum induction can be used as an alternative investigation to bronchoscopy in suspected PTB patients who are able to self-expectorate. Induced sputum is a sensitive investigation for suspected PTB patients but with a low diagnostic yield. Referral guidelines are suggested.     

Clinical diagnosis of smear-negative pulmonary tuberculosis: an audit of diagnostic practice in hospitals in Malawi.

SETTING: Thirty-seven hospitals in Malawi. OBJECTIVE: To audit the hospital practice of clinically diagnosing adults with smear-negative pulmonary tuberculosis (PTB). DESIGN: A cross-sectional survey of adults aged 15 years or above who were registered and receiving inpatient treatment for smear-negative PTB. An assessment of each patient was carried out to determine 1) the number of recommended diagnostic guidelines (cough >3 weeks, no response to antibiotics, negative sputum smears and a chest radiograph compatible with PTB) used by hospital staff in making the diagnosis of PTB, and 2) whether the clinical diagnosis of smear-negative PTB was correct according to criteria set by the study. RESULTS: There were 259 patients, 127 men and 132 women, with a mean age of 37 years; 93% had a cough >3 weeks, 95% had received one or more courses of antibiotics, 92% had submitted sputum samples for smear examination and 97% had chest radiographs performed. In 148 (57%) patients, all four diagnostic guidelines were used, and in 238 (92%) patients three or more were used. The diagnosis of smear-negative PTB was considered correct by study criteria in 203 (78%) patients. In the remainder, 22 (8%) were considered to have extrapulmonary TB and 34 (14%) another diagnosis. CONCLUSION: Hospital practices in the diagnosis of smear-negative PTB are reasonable, although there is room for improvement with in-service training and regular audits of practice.     

Clinical and epidemiological evaluation of tuberculosis in Serbia, 1990-2004.

SETTING: Republic of Serbia, excluding Kosovo. OBJECTIVE: To estimate the clinical and epidemiological pattern of tuberculosis (TB) in Serbia during the period 1990-2004. DESIGN: A retrospective analysis of clinical and epidemiological data on TB patients registered in annual TB reports. RESULTS: During the 15-year period, TB incidence levelled off in Serbia. The slightly decreasing trend occurred in both total pulmonary TB (PTB) and laboratory confirmed PTB (PTB+) incidence (P > 0.05), while the trend of extra-pulmonary TB (EPTB) incidence increased slightly (P > 0.05). During the same period, TB mortality showed a significantly decreasing trend (P < 0.05). The mean annual proportion of PTB+ cases among newly reported PTB cases was 62.7%. The mean proportion of EPTB cases among total TB cases was 6.1%. The mean percentage of cases with resistance to at least one anti-tuberculosis drug was 4.8%. CONCLUSION: Thanks to the good organisation and efficient work of anti-tuberculosis dispensaries in Serbia, as well as to the low incidence of AIDS and low frequency of Mycobacterium tuberculosis resistant strains, TB incidence did not increase during the period observed and TB mortality significantly decreased, despite markedly deteriorated socio-economic conditions during the 1990s.     

Extra-pulmonary tuberculosis at a regional hospital in Thailand

The purpose of this study was to analyze the cases of extra-pulmonary tuberculosis (EPTB) at Maharat Nakhon Ratchasima Hospital, a tertiary care regional hospital in Northeast Thailand. There were 398 cases of EPTB (46.9%) and 450 cases of pulmonary tuberculosis (PTB) (53.1%). The mean age of EPTB patients (47.58 years) was lower than that of PTB patients (51.6 years) (p < 0.01). Human Immunodeficiency Virus (HIV) seropositivity was found in 50 cases of EPTB (12.6%) and 55 cases of PTB (12.2%) which was not significantly different. The common sites of extra-pulmonary involvement were the lymph nodes (29.7%), followed by the pleura (27.4%), the bones and spine (25.1%), the meninges and brain (4.5%), the pericardium (3.5%) and the gastrointestinal tract (3.0%). Disseminated TB occurred in only 8 cases (2.0%). HIV seropositivity rates were more common in disseminated TB (OR 41.51, 95% CI 4.98-34.5), TB of the meninges and brain (OR 4.47, 95% CI 1.57-12.6) and TB of the lymph nodes (OR 3.49, 95% CI 1.86-6.54) and were less common in TB of the bones and spine (OR 0.05, 95% CI 0.01-0.37) and TB of the pleura (OR 0.24, 95%CI 0.09-0.63).     

Accuracy of an interferon-gamma release assay to detect active pulmonary and extra-pulmonary tuberculosis.

OBJECTIVE: To examine the performance of an interferon-gamma (IFN-gamma) release assay (QuantiFERON-TB 2G assay [QFT-G]) to detect Mycobacterium tuberculosis infection in a Japanese general hospital, for the diagnosis of active pulmonary tuberculosis (PTB) and extra-pulmonary tuberculosis (EPTB). DESIGN: We prospectively examined the performance of QFT-G in 194 patients suspected of active TB. Diagnosis was confirmed by 1) positive M. tuberculosis cultures, or 2) clinical manifestations or laboratory or pathological findings consistent with active TB and response to specific therapy. RESULTS: Three patients with indeterminate QFT-G results were excluded. Among the remaining 191 patients, 77 had active TB. When the cut-off concentration of IFN-gamma was set at 0.35 IU/ml, as recommended by the manufacturer, the assay was positive in 69 patients and negative in 122. The sensitivity of the assay was 76.6% in all patients, 74.5% in the 47 patients with PTB and 80.0% in the 30 patients with EPTB. The overall specificity of the assay was 91.2%. CONCLUSION: Although the specificity of the QFT-G to detect active TB was high and its sensitivity low, it was as accurate for the detection of active EPTB as for PTB when the 0.35 IU/ml INF-gamma cut-off concentration was used.     

How can detection of infectious tuberculosis be improved? Experience in the Somali region of Ethiopia.

In early 1999, 48% of pulmonary tuberculosis (PTB) cases detected in the Somali region of Ethiopia were smear-positive. Actions at the laboratory level and peer-review of smear-negative PTB diagnoses were proposed. Clinicians knew, but did not adhere to, the algorithm recommended by the National Tuberculosis Programme for these diagnoses, partly due to the costs involved to patients. Challenging clinicians, in a non-threatening way, to become more clinically rigorous proved successful, and the proportion of smear-positive PTB increased to 65%. Operational research is needed to assess the feasibility of these widely-recommended smear-negative PTB diagnosis guidelines.     

A unified treatment regimen for new cases of tuberculosis in resource-poor countries: a study in a rural district in Malawi.

An oral ambulatory unified treatment regimen was introduced in Ntcheu District, Malawi, between April 1996 and June 1997 for all new patients (600) with tuberculosis (TB). There was no change in the case finding pattern compared with the previous 5 years; 65% of new smear-positive pulmonary tuberculosis (PTB) patients completed treatment, not significantly different compared with the previous 3 years. Treatment completion was significantly lower in patients with smear-negative PTB and extra-pulmonary tuberculosis, due mainly to high mortality rates (40% and 41% respectively). In a rural district with high human immunodeficiency virus sero-prevalence rates in TB patients, case finding and end of treatment outcome of the oral unified regimen were comparable to those of previous regimens.