Health-seeking behaviour among adults with prolonged cough in Vietnam

Objective To assess health‐seeking behaviour among adults with prolonged cough in a population‐based, nationally representative sample in Vietnam. Methods Cross‐sectional survey conducted from September 2006 to July 2007. All inhabitants aged ≥15 years were invited for screening for cough, history of tuberculosis (TB) treatment and chest X‐ray (CXR) examination. TB suspects, defined as any survey participant with CXR abnormalities consistent with TB, or productive cough for more than 2 weeks or TB treatment either currently or in the preceding 2 years submitted sputum specimens for smear examination and culture and provided information on health‐seeking behaviour in an in‐depth interview. Results Of 94 179 persons participating in the survey, 4.6% had prolonged productive cough. Forty‐four percentage of those had sought health care and reported pharmacies (35%), commune health posts (29%), public hospitals (24%) and private physicians (10%) as first point of contact. Only 7% had undergone sputum smear examination. Of TB suspects with prolonged productive cough, 2.9% were diagnosed with TB; 10.2% of these reported smear and 21.9% reported X‐ray examination when visiting a health care facility. The average patient delay was 4.1 weeks (95% CI: 3.9–4.4) among cough suspects and 4.0 weeks (95% CI: 3.1–4.9) among TB cases. Conclusions In this Vietnamese survey, nearly half of persons with cough for more than 2 weeks had visited a health care provider. The commonest first health facility contacted was the pharmacy. Sputum smears were rarely examined, except in the provincial TB hospital. Our findings highlight the need to improve diagnostic practices by retraining health staff on the performance of sputum examination for TB suspects.     

Health care seeking among individuals with cough and tuberculosis: a population-based study from rural India.

SETTING: Ujjain district, Madhya Pradesh, India. OBJECTIVE: To describe and compare health care seeking among men and women with cough of >3 weeks, with special focus on the utilisation of private and public health care. DESIGN: A population-based cross-sectional survey including 45 719 individuals aged > or = 15 years. RESULTS: The prevalence of cough was respectively 2.8% and 1.2% among men and women. The majority of men and women reported seeking health care for their symptoms (69% vs. 71%), but only 23% visited a public provider at some point during their illness. A similar health care seeking pattern was found for patients diagnosed with tuberculosis (TB) in our survey. No significant differences in health care seeking were found between men and women. Only 13% of those seeking care reported having had a sputum smear examination since the onset of cough. Factors associated with sputum examination were history of TB, haemoptysis and visiting a public provider. CONCLUSION: The low utilisation of public health care services and the few sputum examinations reported in this rural Indian setting illustrate the need for improved diagnostic practices as well as involvement of private providers in TB control activities.     

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.     

Prevalence of pulmonary tuberculosis among respiratory symptomatic subjects in an out-patient primary health unit.

SETTING: Out-patient primary health unit (OPHU) in Rio de Janeiro City, Brazil. OBJECTIVE: To evaluate the impact on the detection of tuberculosis (TB) cases of reducing the time of respiratory symptoms from 'cough > or = 3 weeks' to 'cough > or = 1 week' as a criteria for TB case finding among individuals visiting an OPHU for any other reason. DESIGN: Cross-sectional study. RESULTS: During the period of the study, 10.7% (765/ 7174) of subjects reported cough > or = 1 week. Among 542 subjects enrolled in the study with cough > or = 1 week, 15 (2.7%) cases were diagnosed with pulmonary tuberculosis (PTB, 2767/100000). The probability of detecting TB in the OPHU setting among subjects seeking care for respiratory symptoms was significantly higher than among those presenting to the OPHU for other reasons (OR 31.5, 95% CI 4.1-241.9; P < 0.0001). The probability of identifying TB among patients seeking care due to respiratory symptoms was not influenced by the duration of cough (P = 0.7). CONCLUSION: These findings suggest that the screening criteria for TB case finding of cough for less than the usual 3 weeks among patients who attend a health facility due to respiratory symptoms in settings with a high prevalence of TB may significantly improve the proportion of TB cases diagnosed.     

Patient and health system delays in the diagnosis and treatment of tuberculosis in Southern Taiwan.

SETTING: Tainan city, Tainan county and 13 townships of Kaohsiung county, Southern Taiwan. OBJECTIVE: To measure delays in the diagnosis and treatment of sputum-positive tuberculosis (TB) and to determine factors associated with delays in seeking health care (patient delay) and in starting anti-tuberculosis treatment (health system delay). DESIGN: A population-based patient interview study. RESULTS: Median patient delay was 7 days (range 0-730). Median health system delay was 23 days (range 0-489), 13 for smear-positive patients and 37 for smear-negative patients (P < 0.005). Median total delay was 44 days (range 0-730). Age <65 years was associated with longer patient delay. Negative smear, absence of haemoptysis, not having a chest radiograph at the first medical consultation and visiting clinics for first consultation were associated with a longer health system delay. Age <65 years, negative smear and cough as the only presenting symptom were associated with longer total delay. CONCLUSION: Patient delay was substantially shorter than health system delay. To reduce health system delay, clinics need to be involved and the referral mechanism must be strengthened. Physicians should maintain high alert for TB and perform prompt sputum smear examinations.     

Duration of cough, TB suspects' characteristics and service factors determine the yield of smear microscopy

Objective To determine the efficiency of routine tuberculosis (TB) case detection by examining sputum smear positivity for acid‐fast bacilli in relation to duration of cough, characteristics of TB suspects examined and health service factors. Method We combined patient interviews with routine data from laboratory registers in 6 health care facilities in San Juan de Lurigancho district, Lima, Peru. A TB case was defined as a TB suspect with at least one positive sputum smear. We calculated adjusted odds ratios with 95% confidence intervals for the association between smear positivity and health service and patient’s characteristics. Results Smear positivity was 7.3% (321/4376). Of the 4376 adults submitting sputa, 55.3% (2418) reported cough for <14 days. In this group, smear microscopy yielded 3.2% (78/2418) positive results vs. 12.4% (243/1958) in patients coughing for 14 or more days. Having cough for >2 weeks, being referred by health care staff, attending a secondary‐level health care facility, male sex and age between 15 and 44 years were independent determinants of smear positivity. Conclusions Routine case detection yields a low proportion of smear‐positive cases because of the inclusion of a high proportion of patients without cough or coughing for <2 weeks. Adherence to the national TB control programme guidelines on the selection of TB suspects would have a positive impact on the smear positivity rate, reduce laboratory costs and workload and possibly improve the reading quality of smear microscopy.     

四川省成都市入户调查集中推荐可疑症状者检查发现肺结核患者分析

目的 探讨入户调查、集中推荐发现病人方式对提高肺结核病人发现的作用。 方法 采取政府组织、部门参与、开展健康教育,发动群众自报互报;镇村干部配合、乡村医生入户调查、登记常住人口,以当面询问与观察的方式发现线索患者,并集中推荐到指定医院初筛,疑似患者由结防机构定诊。 结果 成都市于2009年先后在9个区县入户登记应调查人数3 910 504人,实际调查3 817 928人,调查率97.6%,新发现活动性肺结核411例,其中新发涂阳172例,占41.8%;新发现活动性病例数与涂阳新病例数分别占同期CDC登记总病例数的23.8%和21.9%。 结论 适时开展入户调查集中推荐可疑者就诊是提高病人发现率的有效方法 。通过入户调查、集中推荐工作的实施,有利于现代结核病控制策略落实到基层;有利于提高群众推荐可疑者、可疑者主动就诊的积极性,提高肺结核患者的发现。     

Prevalence of tuberculosis suspects and their healthcare-seeking behavior in urban and rural Jordan

To determine the prevalence and healthcare-seeking behavior of tuberculosis (TB) suspects in Middle and South Jordan. A community-based survey was carried out between June-September 2005, whereby 61,730 adult household members were inquired about the presence of persistent cough for more than three weeks to identify TB suspects. These adults were then interviewed and referred to the nearest health center for clinical and sputum smear examination. Of the 61,730 surveyed household members, 1,544 (2.51%) were identified as TB suspects, of these two were sputum smear positive pulmonary TB. The first action with the onset of symptoms was to visit the health centers. Reasons for timely seeking care were accessibility of the facilities and confidence in obtaining a cure, and obstacles were belief that symptoms would resolve and economic constraints in rural residents. Females, rural residents, expatriates, and using private means of transportation were predictors of delay in seeking care for more than three weeks. This study has set the baseline information about the prevalence of TB suspects in Jordan and their healthcare-seeking behavior that shows community preference to seek care at health centers. These should be upgraded and the health workers trained on suspect management to enhance the TB elimination efforts.     

Factors related to health system delays in the diagnosis of pulmonary tuberculosis in Estonia.

OBJECTIVE: To estimate health system delays (HSD) in the diagnosis of pulmonary tuberculosis (PTB) and its risk factors after major social changes in Estonia, and to assess the ability of a completely reformed health care system to diagnose patients with PTB. METHODS: All newly detected symptomatic culture-positive patients with PTB aged > or = 16 years from Southern Estonia during 2002-2003 (n = 185) were interviewed. HSD was defined as the interval from a patient's first contact with a medical provider to the date of TB diagnosis. RESULTS: The factors significantly associated with HSD greater than the median (19 days) and the 75th percentile (40 days) were smear negativity, absence of cough among symptoms, absence of chest X-ray during the first visit and age > 60 years. A significantly shorter HSD was determined in non-Estonians and unemployed patients. HSD was not associated with the specialty of the doctor first contacted by the patient. CONCLUSION: This study in Southern Estonia shows that the health care system is still managing the diagnosis of PTB without significant delays, even after substantial modifications in the health care system resulting from social reform in a post-socialist country, and that family physicians can manage PTB patients successfully.     

Predictors of delayed sputum smear conversion among pulmonary tuberculosis patients in Kota Kinabalu,Malaysia: A retrospective cohort study

Smear-positive pulmonary tuberculosis (SPPTB) is the major contributor to the spread of tuberculosis (TB) infection, and it creates high morbidity and mortality worldwide. The objective of this study was to determine the predictors of delayed sputum smear conversion at the end of the intensive phase of TB treatment in Kota Kinabalu, Malaysia.This retrospective study was conducted utilising data of SPPTB patients treated in 5 TB treatment centres located in Kota Kinabalu, Malaysia from 2013 to 2018. Pulmonary TB (PTB) patients included in the study were those who had at least completed the intensive phase of anti-TB treatment with sputum smear results at the end of the 2nd month of treatment. The factors associated with delayed sputum smear conversion were analyzed using multiple logistic regression analysis. Predictors of sputum smear conversion at the end of intensive phase were evaluated.A total of 2641 patients from the 2013 to 2018 periods were included in this study. One hundred eighty nine (7.2%) patients were identified as having delayed sputum smear conversion at the end of the intensive phase treatment. Factors of moderate (advanced odd ratio [aOR]: 1.7) and advanced (aOR: 2.7) chest X-ray findings at diagnosis, age range of >60 (aOR: 2.1), year of enrolment 2016 (aOR: 2.8), 2017 (aOR: 3.9), and 2018 (aOR: 2.8), smokers (aOR: 1.5), no directly observed treatment short-course (DOTS) supervisor (aOR: 6.9), non-Malaysian citizens (aOR: 1.5), and suburban home locations (aOR: 1.6) were associated with delayed sputum smear conversion at the end of the intensive phase of the treatment.To improve sputum smear conversion success rate, the early detection of PTB cases has to be fine-tuned so as to reduce late or severe case presentation during diagnosis. Efforts must also be in place to encourage PTB patients to quit smoking. The percentage of patients assigned with DOTS supervisors should be increased while at the same time ensuring that vulnerable groups such as those residing in suburban localities, the elderly and migrant TB patients are provided with proper follow-up treatment and management.     

Microbiological validation of smear microscopy after sputum digestion with bleach; a step closer to a one-stop diagnosis of pulmonary tuberculosis

BACKGROUND: Smear microscopy is relatively insensitive for the diagnosis of TB. The digestion of sputum with household bleach prior to smear preparation has been reported to improve its sensitivity. This method has not been validated. METHODS: Seven hundred and fifty six patients with symptoms suggestive of pulmonary TB (PTB) were asked to submit 3 sputum specimens for direct microscopy. One specimen was selected at random for culture and another specimen was digested to prepare a further smear. The WHO case definition (>or=2 positive smears or one positive smear and positive culture) was used to compare the sensitivity and specificity of the smears. FINDINGS: Four hundred and fifty five (60%) patients were culture-positive. Of these, 235 (31%) had "definite" PTB and 223 (29%) "very likely" PTB (smear-negative, culture-positive). The WHO case definition identified 51% (235/458) of the patients with "definite" or "very likely" PTB. One digested smear detected 219 (93%) of the 235 patients with "definite" PTB and 10 patients with "very likely" PTB (sensitivity (95%CI) 50% (45-55%); specificity 99% (97-100%)). The positive and negative predictive values for one digested smear were 98% (95-99%) and 56% (52-60%) respectively, which were not different (p>0.5) to the WHO case definition (100% and 57%, respectively). INTERPRETATION: One bleach-digested smear is as sensitive and specific as the WHO case definition for the diagnosis of PTB.     

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.     

A study of patient's and doctor's delay in patients with pulmonary tuberculosis discovered by visiting doctors with symptoms in particular on doctor's delay

Epidemiological trend of tuberculosis in Japan has reversed recently. The incidence of pulmonary tuberculosis (PTB) patients has increased again in Japan, and many outbreaks of PTB including nosocomial outbreaks in health-care facilities have been reported. The purpose of this study is to investigate patient's delay (interval between onset of the disease and first visit to a doctor) and doctor's delay (interval between first visit to a doctor and diagnosis as TB) in patients with PTB discovered by visiting doctors with symptoms, and especially, to investigate causes of doctor's delay in details. Of 236 PTB patients who were admitted to our hospital for treatment in 1997, 118 patients (85 males, 33 females) who were detected by their symptomatic visits were enrolled in to this study. 97 were initial treatment cases and the others were re-treatment cases. Among 34 initial treatment cases who were first seen at a general hospital and diagnosed as PTB by a close medical checkup after admission to our hospital, the 50 percentile of patient's delay was 17.0 days, and the 80 percentile was 36.4 days. The 50 percentile doctor's delay was 19.6 days, and the 80 percentile was 64.2 days. The average hospital stay was 16.2 days, the 50 percentile hospital stay was 7.8 days, and 80 percentile hospital stay was 23.5 days. On the sputum test for acid fast bacilli (AFB) performed on admission to our hospital, 26(76%) out of 34 cases were positive for tubercle bacilli, with 18 cases were positive for smear and 8 cases positive for culture. Therefore, risk of nosocomial infection was suspected. Doctor's delay had been attributed mainly to insufficient medical checkup. Among 25 initial treatment cases in whom doctor's delay as more than 4 weeks, 11 cases (44%) showed delay in chest X-ray examination and 8 cases (32%) ordered no sputum examination in spite of recognition of abnormal shadows on chest X-ray. On the sputum test for AFB on admission to our hospital, 22 (88%) out of 25 cases were positive for tubercle bacilli. Therefore, it is assumed that the delay in the adequate medical checkup was accountable for the doctor's delay. Shortening of the doctor's delay could be possible if hospitals perform the sputum examination for AFB and chest X-ray examinations properly for patients with respiratory symptoms.     

Validation of the surveillance system for tuberculosis in Botswana.

SETTING: Gaborone and Francistown, Botswana, where surveillance data in the 1997 Electronic Tuberculosis (TB) Register suggest that 39% of pulmonary TB patients did not have pre-treatment sputum smear microscopy performed. OBJECTIVE: To determine the proportion of patients with reportedly missing pre-treatment sputum smear results in 1997 who had smears examined, and to identify stages in the system where results were lost. METHODS: Patients with pulmonary TB in 1997 who were missing pre-treatment sputum smear results in the Electronic TB Register were cross-matched with laboratory records; medical records were reviewed. RESULTS: Of 374 patients with pre-treatment sputum smear results missing, 224 (60%) actually had had a sputum smear examined in the laboratory. The proportion of pulmonary TB patients in Gaborone and Francistown who did not have sputum examined was therefore 16% instead of 39%. Most missing results (69%) had not been transcribed from the laboratory results onto the TB Treatment Card. Patients who had a negative smear result or who sought care at a clinic that was different from where their diagnostic evaluation had been initiated were more likely to have missing results. CONCLUSIONS: The actual performance of the Botswana National TB Programme with respect to sputum microscopy examination is much better than surveillance indicators suggest. In addition to sputum collection, proper recording of results needs reinforcement among health care workers to improve routine performance indicators.     

结核抗体IgG检测辅助诊断结核病的应用价值

目的 探讨结核抗体IgG检测(简称“IgG检测”)辅助诊断结核病的应用价值。方法 收集黑龙江省传染病防治院2015年7月至2016年5月期间,具有IgG检测、抗酸杆菌涂片(简称“涂片”)镜检、结核分枝杆菌液体培养(简称“液体培养”)、CT扫描及临床诊断等资料的住院及门诊患者,共计1494例,其中继发性肺结核1020例(肺结核组)、肺外结核54例(肺外结核组)和排除结核病的其他肺部疾病420例(其他肺病组),对比分析不同患者的临床资料。结果 1020例肺结核患者和54例肺外结核患者的IgG检测阳性率分别为73.33%(748/1020)、62.96%(34/54),高于涂片镜检[分别为43.24%(441/1020)、20.37%(11/54)]和液体培养[分别为61.37%(626/1020)、29.63%(16/54)](χ ²=190.02,P<0.001;χ ²=20.15, P<0.001; χ ²=33.18,P<0.001; χ ²=12.07,P=0.001);IgG检测肺结核与其他肺病患者的阳性率(6.90%,29/420)差异有统计学意义(χ ²=553.47,P<0.001)。IgG检测1440例肺部疾病患者的敏感度、特异度、总符合率分别为73.33%(748/1020)、93.10%(391/420)、79.10%(1139/1440)。1020例肺结核患者中,涂片镜检阳性者的IgG检测阳性率(86.85%,383/441)与涂片镜检阴性者的IgG检测阳性率(63.04%,365/579),以及液体培养阳性者的IgG检测阳性率(80.51%,504/626)与液体培养阴性者的IgG检测阳性率(61.93%,244/394)的差异均有统计学意义(χ ²值分别为72.56、42.70,P值均<0.001)。分别以涂片镜检和液体培养为标准,IgG检测1020例肺结核组患者的敏感度、特异度、总符合率分别为86.85%(383/441)和80.51%(504/626) 、36.96%(214/579)和38.07%(150/394)、58.53%(597/1020)和64.12%(654/1020)。1020例肺结核组患者中涂阴培阴(菌阴)肺结核患者为372例(36.47%),其IgG检测阳性率为61.29%(228/372),阳性患者的CT扫描表现以斑片、条索状阴影(83.77%,191/228)多见。420例其他肺病患者IgG检测假阳性率为6.90%(29/420),与肺部感染(62.07%,18/29)和肿瘤(13.79%,4/29)患者有少量交叉反应。 结论 结核抗体IgG检测具有较高的敏感度和特异度,对结核病,尤其是对菌阴肺结核和肺外结核检出具有较高的辅助诊断价值。     

Factors associated with a clinician's decision to stop anti-tuberculosis treatment before completion.

OBJECTIVES: To investigate the diagnosis of pulmonary tuberculosis (PTB) and factors associated with a clinician's decision to stop anti-tuberculosis treatment before completion. DESIGN: The medical charts of all citizens of Taipei City, Taiwan, reported to have received treatment for PTB in 2003 were investigated. RESULTS: Of 1126 PTB patients, 512 (45.5%) started treatment immediately based solely on chest X-ray (CXR) findings; treatment for 214 (19.0%) was based on a positive sputum smear for acid-fast bacilli, for 261 (23.2%) it was based on other findings and for 139 (12.3%) it was based on a positive mycobacterial culture. Of the 1126 PTB patients, 156 (13.9%) had their diagnosis of TB changed by a clinician. Multivariate analysis shows that patients whose diagnosis was based on CXR or other findings, female patients, patients who interrupted treatment for 2 months, patients who continued care at other health facilities (transfer) and patients with lung cancer were significantly more likely to have their diagnosis changed than other groups. CONCLUSION: A substantial proportion of patients were prescribed anti-tuberculosis treatment based on CXR findings alone, and a considerable proportion were advised to stop treatment before completing a full course, findings that require the immediate attention of Taiwan's National Tuberculosis Programme.     

交叉引物恒温扩增检测技术在疑似肺结核患者临床诊断中的价值

目的 评估交叉引物恒温扩增(cross priming amplification, CPA)检测技术在肺结核早期临床诊断中的应用价值。 方法 以2016年1—10月广东省佛山市和江门市及所辖7个县(区)级结核病防治机构(简称“结防机构”)就诊的初诊疑似肺结核患者为研究对象,共纳入患者6507例;所有患者均进行了胸部影像学检查并送检痰标本进行涂片镜检、固体培养和CPA检测,培养阳性菌株进行菌种鉴定,项目点临床医生结合实验室和临床检查结果对纳入患者进行初诊诊断,国家级临床专家对初诊临床诊断结果进行现场复核。分析项目地区确诊活动性肺结核患者中病原学阳性患者所占比例,并与专家复核后的临床诊断结果进行比较,分析涂片镜检、固体培养和CPA诊断肺结核的敏感度及特异度。 结果 6507例疑似肺结核患者中,涂片镜检、固体培养和CPA检测阳性率分别为18.2%(1187/6507)、25.0%(1629/6507)和23.9%(1555/6507)。3199例临床确诊为活动性肺结核患者中,涂片联合培养阳性检出率为48.5%(1550/3199),涂片联合CPA阳性检出率为47.9%(1531/3199),涂片、培养和CPA三种方法联合检测阳性率为54.4%(1740/3199)。以临床诊断结果为标准,涂片镜检、固体培养和CPA检测诊断活动性肺结核的敏感度分别为35.0%(1120/3199)、46.4%(1485/3199)和44.6%(1428/3199),特异度分别为98.0%(3241/3308)、95.7%(3164/3308)和96.2%(3181/3308)。 结论 县(区)级结防机构可应用CPA检测技术用于疑似肺结核患者的快速诊断,多种诊断技术联合应用可显著提高活动性肺结核患者的病原学诊断阳性率。     

Induced sputum improves the diagnosis of pulmonary tuberculosis in hospitalized patients in Gaborone, Botswana

SETTING: Low sensitivity of acid-fast bacilli (AFB) sputum smears and absence of productive cough are obstacles to the diagnosis of pulmonary tuberculosis (PTB) in hospitals that lack access to bronchoscopy. OBJECTIVES: To evaluate induced sputum, gastric content, blood and urine specimens to improve PTB diagnosis in patients not diagnosed by expectorated sputum AFB smears. DESIGN: Patients admitted to the medical wards of a large public hospital in Gaborone, Botswana, were prospectively enrolled if they had symptoms consistent with PTB, an abnormal chest radiograph, were treated empirically with anti-tuberculosis chemotherapy or had no improvement on antibiotics, and had a non-productive cough or AFB smear-negative sputum. Induced sputum was stained for AFB and Mycobacterium tuberculosis cultures were performed on induced sputum, gastric contents, urine and blood. RESULTS: Of 140 patients meeting the enrollment criteria, 113 (81%) were human immunodeficiency virus (HIV) positive. Fifty-seven (41%) had PTB based on positive cultures from one or more sites, including 48 (84%) from induced sputum, 17 (30%) urine, 13 (23%) gastric contents and 7 (12%) blood. AFB smears were positive in only 18 (32%) culture-proven PTB cases. CONCLUSION: Induced sputum cultures greatly enhanced M. tuberculosis detection in patients with a high prevalence of HIV/AIDS in a hospital without access to bronchoscopy.     

Detection of pulmonary tuberculosis in patients with a normal chest radiograph

OBJECTIVES: To describe the early symptoms of pulmonary tuberculosis (TB) when the chest radiograph (CXR) is normal. SETTING: Centralized, provincial TB control program. SUBJECTS: Twenty-five patients with culture-positive pulmonary TB and a normal CXR were identified from a review of 518 consecutive patients with culture-positive pulmonary TB in the province of Saskatchewan from January 1, 1988 to March 31, 1997. Patients with abnormal CXRs at the time of diagnosis were excluded from the analysis. RESULTS: Twenty-three of the 25 patients (92%) were symptomatic at the time of diagnosis, with cough/sputum (76%) being reported most commonly. Eleven patients were identified because of contact tracing from cases of infectious pulmonary TB, while the other 14 patients were identified because of an investigation of symptoms. Twenty-four patients (96%) exhibited one or more symptoms of cough for > 1 month, fever for > 1 week, or skin-test conversion after contact with infectious TB. The sputum smear of only one patient was positive. Two patients were pregnant at the time of diagnosis, one patient was HIV-positive, and one patient demonstrated isoniazid-resistant organisms on sensitivity testing. Five patients were diagnosed as having primary TB associated with Mantoux skin-test conversion. The incidence of culture-positive pulmonary TB with a normal chest radiograph was < 1% in the period from 1988 to 1989 and steadily increased to 10% in the period from 1996 to 1997. CONCLUSIONS: Culture-positive pulmonary TB with a normal CXR is not uncommon, and the incidence of this presentation is increasing. Patients with this presentation of TB are typically symptomatic and/or are detected by contact tracing to infectious cases of pulmonary TB. The results suggest that patients presenting with a cough for > 1 month, with a fever for > 1 week, or with documented skin-test conversion < 2 years after known exposure to infectious TB should have sputum submitted for a Mycobacterium tuberculosis smear and culture despite a normal CXR.     

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.