Diagnosing HIV-associated tuberculosis: reducing costs and diagnostic delay.

SETTING: University-affiliated hospital in South Africa. OBJECTIVE: To assess the time to diagnosis and the yield and laboratory cost of diagnostic procedures in human immunodeficiency virus (HIV) associated tuberculosis. DESIGN: Cohort study. PATIENTS: Adult HIV-infected patients with newly-diagnosed tuberculosis admitted over a 2-year period. RESULTS: A total of 141 admissions fulfilled the case definition. Sputum smear yield (43% overall) correlated strongly with chest radiograph appearance but not with CD4+ lymphocyte count. Sputum smear yield was approximately 40% per sample sent, resulting in a high cumulative yield when > or = three samples were sent. Smear of sputum or wide needle lymph node aspirates were the most cost-effective diagnostic methods. Significant diagnostic delay occurred in sputum smear-negative patients. Most patients with sputum smear-negative tuberculosis had either pleural effusions or lymphadenopathy. Lymph node biopsy had a high diagnostic yield even in patients with symmetrical nodes, but was under-utilised in this group. There was unnecessary expenditure on cultures, with many patients having several positive cultures. CONCLUSION: Repeated sputum smear examination produces a high cumulative yield in HIV-associated tuberculosis. Considerable savings in laboratory utilisation and bed occupancy would have been made if a streamlined diagnostic approach with greater use of lymph node aspirate and early pleural or lymph node biopsy had been followed.     

Value of smear and PCR in bronchoalveolar lavage fluid in culture positive pulmonary tuberculosis.

At present, further investigations are needed in patients with suspected pulmonary tuberculosis (TB) and either negative sputum smear or without sputum. The aim of the present study was to analyse the yield of bronchoalveolar lavage fluid (BALF) smear and PCR in patients with confirmed pulmonary TB. Patients with a positive culture for Mycobacterium tuberculosis complex in sputum or BALF were analysed over 5 yrs. In total, 90 out of 230 (39%) patients with culture-positive pulmonary TB had a positive sputum smear, and 120 patients underwent bronchoscopy. BALF smear was positive in 56 (47%), BALF PCR in 93 (78%) patients, and BALF smear and/or PCR was positive in 83%. In total, 71 patients who underwent bronchoscopy and had complete clinical records were further analysed. BALF (smear or Mycobacterium tuberculosis complex-PCR) allowed a rapid diagnosis in 10 (59%) out of 17 patients who had a negative sputum smear, and 49 (91%) out of 54 patients without sputum production. Of these 71 patients, 12 (17%) were only culture positive. Rapid diagnosis of pulmonary TB by smear and/or PCR was made in 190 out of 210 patients (90%) in sputum or BALF. In conclusion, combined use of bronchoalveolar lavage fluid smear and Mycobacterium tuberculosis complex-PCR has a good diagnostic yield in patients with sputum smear-negative tuberculosis or without sputum production.     

Comparison of sputum induction with fiberoptic bronchoscopy in the diagnosis of tuberculosis: experience at an acquired immune deficiency syndrome reference center in Rio de Janeiro, Brazil

Many patients with suspected pulmonary tuberculosis (PTB) do not produce sputum spontaneously or are smear-negative for acid-fast bacilli (AFB). We prospectively compared the yield of sputum induction (SI) and fiberoptic bronchoscopy with bronchoalveolar lavage (BAL) for the diagnosis of PTB in a region with a high prevalence of tuberculosis and human immunodeficiency virus (HIV) infection. Fifty seven percent (143 of 251) of patients had diagnoses of PTB, of whom 17% (25 of 143) were HIV seropositive. There were no significant differences in the yields of AFB smears or cultures whether obtained via SI or BAL. Among 207 HIV-seronegative patients, the AFB smear and mycobacterial culture results from specimens obtained by SI and BAL were in agreement in 97% (202 of 207) (kappa test = 0.92) and 90% (186 of 207) (kappa test = 0.78), respectively. Among HIV-seropositive patients the agreements between AFB smear and culture results for SI and BAL specimens were 98% (43 of 44) (kappa test = 0.93) and 86% (38 of 44) (kappa test = 0.69), respectively. We conclude that SI is a safe procedure with a high diagnostic yield and high agreement with the results of fiberoptic bronchoscopy for the diagnosis of PTB in both HIV-seronegative and HIV-seropositive patients.     

Thoracoscopic pleural biopsy improves yield of Xpert MTB/RIF for diagnosis of pleural tuberculosis

Background and objective

Extrapulmonary tuberculosis (EPTB) accounts for ~15% of all TB patients, and TB pleural effusion is the second most common site of EPTB. The diagnosis of pleural TB is challenging due to the pauci‐bacillary nature of the disease. Histopathology of thoracoscopically obtained pleural biopsy provides the highest diagnostic yield. The Xpert MTB/RIF assay (Xpert) is a PCR test that can identify both Mycobacterium tuberculosis (MTB) and rifampicin resistance. Currently, there is a lack of clarity regarding the value of Xpert on pleural tissue. We report our experience of using Xpert on thoracoscopic pleural biopsy samples.

Methods

We retrospectively reviewed the records of patients who underwent thoracoscopy in our institution over a 1‐year period. Relevant clinical details; indications; and results of tests on pleural tissue and fluid, including histopathology, mycobacterial cultures and Xpert, were extracted.

Results

Of the 156 patients who underwent thoracoscopy, 73 (47%) had TB, 66 (42%) malignancy and 17 (11%) other conditions. Histopathology was diagnostic in all the 73 TB patients (100%). The yields of the microbiological tests against histopathology on thoracoscopic biopsy sample and pleural fluid were: pleural tissue Xpert 45%, pleural tissue culture 39%, pleural fluid culture 17% and pleural fluid Xpert 14%. Pleural tissue provided higher yields than fluid in both Xpert and culture (P < 0.05). Pleural tissue Xpert provided a higher yield than culture and substantially improved yield compared with closed pleural biopsy as we previously reported.

Conclusion

Thoracoscopic pleural biopsy results in increased sensitivity on Xpert testing.

     

ADA1/ADAp ratio in pleural tuberculosis: an excellent diagnostic parameter in pleural fluid

We analysed the efficacy of pleural adenosine deaminase (ADAp) and the ADA1/ADAp ratio in the diagnosis of pleural tuberculosis in 103 pleural effusions, 27 of which were tuberculosis (TB) and 76 other diagnoses (non-TB). Smears, cultures and pleural biopsies were carried out in all cases, and were used for final diagnosis. The diagnostic yield of the parameters under study were as follows: smears/cultures of mycobacteria in fluid 11.1%/33.3%; biopsy 33.3%/51.8% and tuberculosis granulomas 85.1%. The levels of ADAp and ADA1/ADAp ratio in TB and non-TB groups showed very significant differences (P < 0.00001); in the TB group: ADAp 54.7 +/- 23.5 IU and ADA1/ADAp 0.27 +/- 0.08; in the non-TB group: ADAp 18.3 +/- 43.2 IU and ADA1/ADAp 0.64 +/- 0.14. The assay established ADA levels in pleural fluid > or = 40 IU and an ADA1/ADAp ratio < or = 0.42 as cut-off levels to identify individuals in the TB group, with a sensitivity of 88.8%/100%, a specificity of 92%/98.6%, a positive predictive value (PPV) of 80%/96.4%, a negative predictive value (NPV) of 95.8%/100% and an accuracy of 91.2%/99.02%. The ADAp levels in 27 patients with TB, showed close correlation with the number of monocyte macrophages (P = 0.001), but not with the number of lymphocytes (P = n.s.). The ADA1/ADAp ratio overcomes the limitations of ADAp (false positives and negatives), and is the most useful parameter for diagnosis on account of a high diagnostic yield, low cost and speed of the assay for identifying a pleural tuberculosis diagnosis, when compared with traditional methods.     

2018—2020年深圳市龙华区某综合医院呼吸科加强住院患者结核病病原学检查的效果分析

目的: 分析2018—2020年深圳市龙华区某综合医院呼吸科住院的非已知肺结核及疑似肺结核患者中病原学阳性肺结核患者发现的情况,探索在呼吸科住院患者中进行肺结核早期发现的模式。 方法: 2018年1月至2020年12月,龙华区某综合医院设置留痰室,并配备专职留痰宣教人员,对呼吸科住院的非已知肺结核及疑似肺结核患者中有肺结核可疑症状或临床不能排除肺结核的住院患者(342例)采集痰液(或由医务人员采集支气管肺泡灌洗液或胸腔积液),同时进行涂片、培养、GeneXpert MTB/RIF(简称“GeneXpert”)检测,以发现其中病原学阳性的肺结核患者,分析不同检验策略在病原学阳性患者发现中的价值。 结果: 342例患者中,病原学阳性73例,病原学阳性率为21.3%。单一检测方法中,涂片法检出阳性患者24例(32.9%,24/73),培养法检出阳性患者52例(71.2%,52/73),GeneXpert法检出阳性患者54例(74.0%,54/73);检测方法组合中,涂片+培养检查发现阳性患者53例(72.6%,53/73),涂片+GeneXpert检查发现阳性患者58例(79.5%,58/73),培养+GeneXpert检查发现阳性患者73例(100.0%,73/73)。2020年纳入患者的病原学阳性率最高(27.7%,38/137),其次为2018年(20.6%,20/97),2019年最低(13.9%,15/108),差异有统计学意义(χ²=6.941,P=0.031)。结论: 综合医院呼吸科住院患者中,除已知肺结核及胸部影像学检查提示肺结核患者外,仍存在病原学阳性肺结核患者。建议综合医院与当地有检测能力的机构合作,在肺结核诊断性治疗前留痰送检,以实现病原学阳性肺结核患者发现关口的前移。     

Tuberculous pleural effusion. Twenty-year experience

We reviewed the records of 1,738 cases of tuberculosis seen during the period from 1968 to 1988 in Mobile, Alabama. Seventy cases of tuberculous pleural effusion were identified and constituted 4.9 percent of all disease due to Mycobacterium tuberculosis during this period. Tuberculous pleural effusion was diagnosed if the patient had M tuberculosis cultured from sputum, pleura, or pleural fluid and had a roentgenographic pleural effusion without an alternative explanation for the presence of the effusion. The diagnosis of tuberculous pleural effusion was made in the absence of a positive culture if the patient had an undiagnosed lymphocytic exudative pleural effusion and all clinical and roentgenographic abnormalities resolved on antimycobacterial chemotherapy. The mean age of all patients was 47 +/- 18.4 years. The 70 cases were evenly divided between 35 that were accompanied by roentgenographic pulmonary parenchymal infiltrates and 35 that occurred in the absence of parenchymal infiltrates. We conclude that cultures of all potentially diagnostic specimens (sputum, pleural fluid, and pleura) and an intermediate-strength skin test, are sensitive tests for the diagnosis of tuberculous pleural effusion. In addition, the age of patients with tuberculous pleural effusion appears to be increasing.     

Evaluation of clinical parameters to predict Mycobacterium tuberculosis in inpatients

BACKGROUND: Respiratory isolation has been recommended for all patients with suspected tuberculosis (TB) to avoid transmission to other patients and health care personnel. In implementing these guidelines, patients with and without TB are frequently isolated, significantly increasing hospital costs. The objective of this study was to derive a clinical rule to predict the need for respiratory isolation of patients with suspected TB. METHODS: To identify potential predictors of the need for isolation, 56 inpatients with sputum cultures positive for TB were retrospectively compared with 56 controls who were isolated on admission to the hospital based on clinically suspected TB but whose sputum cultures tested negative for TB. Variables analyzed included TB risk factors, clinical symptoms, and findings from physical examination and chest radiography. RESULTS: Multivariate analysis revealed that the following factors were significantly associated with a culture positive for TB: presence of TB risk factors or symptoms (odds ratio [OR], 7.9 [95% confidence interval (CI), 4.4-24.2]), a positive purified protein derivative tuberculin test result (OR, 13.2 [95% CI, 4.4-40.7]), high temperature (OR, 2.8 [95% CI, 1.1-8.3]), and upper-lobe disease on chest radiograph (OR, 14.6 [95% CI, 3.7-57.5]). Shortness of breath (OR, 0.2 [95% CI, 0.12-0.53]) and crackles noted during the physical examination (OR, 0.29 [95% CI, 0.15-0.57]) were negative predictors of TB. A scoring system was developed using these variables. A patient's total score of 1 or higher indicated the need for respiratory isolation, accurately predicting a culture positive for TB (98% sensitivity [95% CI, 95%-100%]; 46% specificity [95% CI, 33%-59%]). CONCLUSION: Among inpatients with suspected active pulmonary TB, a prediction rule based on clinical and chest radiographic findings accurately identified patients requiring respiratory isolation.     

Utility of blood cultures and incidence of mycobacteremia in patients with suspected tuberculosis in a South African infectious disease referral hospital.

SETTING: A 500-bed government referral institution for patients with tuberculosis and other infectious diseases in Gauteng, South Africa. OBJECTIVES: To assess the usefulness of BACTEC blood cultures over and above that of other microbiological methods for the diagnosis of tuberculosis in patients who are suspected of suffering from tuberculosis. DESIGN: Mycobacterial blood cultures were obtained from patients presenting with symptoms suspicious of tuberculosis and where there was no clinical evidence of other infectious etiologies, and from patients who had failed tuberculosis treatment. RESULTS: Sixteen (22%) of 71 patients included in the study were positive for Mycobacterium tuberculosis on blood culture, while seven (10%) were positive for M. avium complex (MAC). Twelve (75%) of the patients with tuberculosis and positive blood cultures were however also positive for acid-fast bacilli on sputum smears and eight (50%) were initially diagnosed clinically and radiographically as localized pulmonary tuberculosis. Blood cultures positive for mycobacteria were only found among patients with human immunodeficiency virus infection (HIV). CONCLUSIONS: Bacteremia with M. tuberculosis complex was detected in HIV-infected patients with suspected tuberculosis, even in patients presenting with localized pulmonary infection on initial clinical assessment. Among patients with suspected tuberculosis, blood cultures were useful in diagnosing unsuspected MAC disease, but did not add to the diagnostic yield of conventional tests for tuberculosis used routinely, namely sputum microscopy and culture, or occasional biopsy specimens.     

免疫学检测联合痰涂片和痰培养检测在活动性肺结核临床诊断中的价值

目的 分析结核感染T细胞斑点试验(T-SPOT.TB)、结核抗体、痰涂片与痰培养联合检测在活动性肺结核诊断中的临床意义。方法 收集2014年1月至2019年12月北京结核病控制研究所门诊收治的疑似活动性肺结核患者715例,最终诊断为活动性肺结核患者412例(肺结核组),非结核病患者303例(非结核组)。715例患者均行T-SPOT.TB检测、结核抗体检测及痰涂片、痰培养检查;以临床诊断结果为标准,分析4种方法单独及联合检测的临床意义。结果 肺结核组患者中,T-SPOT.TB阳性检出率为83.7%(345/412);非结核组患者中,T-SPOT.TB阳性检出率为20.8%(63/303);两组阳性检出率差异有统计学意义(χ²=2.823,P=0.000)。T-SPOT.TB对活动性肺结核检测的敏感度、特异度、阳性预测值、阴性预测值和准确度分别为83.7%(345/412)、79.2%(240/303)、84.6%(345/408)、78.2%(240/307)、81.8%[(345+240)/715];4种方法联合诊断的敏感度、特异度、阳性预测值、阴性预测值和准确度分别为93.7%(386/412)、50.8%(154/303)、72.1%(386/535)、85.6%(154/180)、75.5%[(386+154)/715]。T-SPOT.TB检测、结核抗体检测及痰涂片、痰培养检查的ROC曲线下面积(AUC)分别为0.815、0.575、0.593、0.715,四项联合检测的AUC为0.894。结论 T-SPOT.TB检测的敏感度、阴性预测值较好,T-SPOT.TB检测联合结核抗体、痰涂片和痰培养检测的敏感度、AUC较高,联合检测可提高对肺结核的诊断效能。     

Diagnostic value of repeated sputum examinations in pulmonary tuberculosis: how many sputum specimens are adequate?

The aim of this study was to assess the value of examining multiple sputum specimens in the diagnosis of pulmonary tuberculosis (PTB). We analyzed sputum smear and culture results of patients diagnosed with culture-proven PTB during 2002. In 1027 patients, the diagnosis was established by detection of Mycobacterium tuberculosis bacilli in sputum samples. The number of sputum specimens submitted to laboratory was one in 634 cases, two in 167 cases, three in 186 cases and more than three in 48 cases. 760 (74%) cases had positive smear examination result. The first sputum smear examination was positive in 82.3% of smear positive cases. Either the first or the second sputum was diagnostic in 94.9% of these cases. Smear examination of third sputum revealed 4.2% additional diagnostic yield. In 863 (84%) cases, culture examination of the first sputum was positive. The second and the third sputum culture examinations revealed additional diagnostic yield of 11% and 4.5%, respectively. Percent 95 of culture-proven cases were diagnosed with the first two sputum cultures. In conclusion the majority of PTB cases can be diagnosed with the examination of two sputum specimens. Three or more sputum specimens submitted obtain a small additional diagnostic yield.     

Comparison of chest computed tomography features between pulmonary tuberculosis patients with culture-positive and culture-negative sputum for non-mycobacteria: A retrospective observational study

Although complication with non-mycobacterial pneumonia among patients with pulmonary tuberculosis (TB) may lead to poor prognosis, discrimination between TB complicated with and without non-mycobacterial pneumonia using radiological imaging has not been fully elucidated. We aimed to clarify the differences in chest computed tomography (CT) features between pulmonary TB patients with culture-positive and culture-negative sputum for non-mycobacteria.We retrospectively included consecutive patients admitted to our hospital from January 2013 to December 2015 for bacteriologically-confirmed pulmonary TB, who were tested by sputum culture for non-mycobacteria, and who underwent chest CT within 2 weeks before or after admission. Chest CT features were compared between pulmonary TB patients who had positive non-mycobacterial cultures and in those who had not.Of 202 patients with pulmonary TB, 186 (92%) were tested by sputum culture for non-mycobacteria and underwent chest CT. Among these, non-mycobacteria were isolated in 118 patients (63%), while 68 patients (37%) had negative cultures. Patients with a positive culture for non-mycobacteria were significantly older and had lower levels of physical activity and albumin, higher levels of C-reactive protein, and a greater number of respiratory failures. By CT, emphysematous lesions, ground-glass opacities, airspace consolidation, air-bronchogram, interlobular septal thickening, bronchiectasis, pleural effusion, pleural thickening, and lymph node enlargement were more frequently in patients with a positive culture for non-mycobacteria. These chest CT features could be helpful for detecting complication with non-mycobacterial pneumonia in patients with pulmonary TB.     

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.     

Impact of sputum gross appearance and volume on smear positivity of pulmonary tuberculosis: a prospective cohort study

ABSTRACT: BACKGROUND: Although checking specimen quality upon sputum collection for acid-fast smear of suspected tuberculosis (TB) cases is recommended, this procedure is based on expert opinion. The purpose of this study was to elucidate the impact of sputum gross appearance and volume on smear positivity among patients with suspected pulmonary TB, according to sex. METHODS: From November 2010 through June 2011, we enrolled consecutive patients suspected to have active pulmonary TB. The association of sputum gross appearance and volume with smear positivity, along with other variables possibly affecting smear positivity such as symptoms, disease extent, and cavity on chest radiograph, were investigated. RESULTS: Among 2,439 patients undergoing TB examination, 170 (113 men, 57 women) with active pulmonary TB were enrolled in the final analysis. They submitted 492 sputa. There were 73 smear-positive patients (42.9%) and 164 smear-positive sputa (33.3%). While gross appearance was associated with smear positivity in both sexes (purulent or blood-tinged sputum (rather than mucoid sputum or saliva); odds ratio (OR), 2.05, 95% confidence interval (CI), 1.21-3.47 in men; OR, 2.78, 95% CI, 1.23-6.26 in women), the amount of sputum specimens was associated with smear positivity in only female patients (4 ml or more versus less than 4 ml; OR, 4.96, 95% CI, 1.98-12.37). CONCLUSIONS: Sputum gross appearance and volume were associated with smear positivity. A volume of 4 ml seems to be the the minimum sputum volume acceptable for smear microscopy in females suspected of TB. Those suspected of TB should be encouraged to expectorate grossly qualified sputum specimens.     

Extrapulmonary tuberculosis in patients with human immunodeficiency virus infection

The annual number of cases of culture-proven extrapulmonary tuberculosis (TB) at our hospital increased from 47 cases in 1983 to 113 cases in 1988. At least 43% (199) of 464 consecutive patients with extrapulmonary TB during this 6-year period were infected with the human immunodeficiency virus (HIV); since HIV serologic testing was not performed routinely the true HIV prevalence is likely to be higher. Of the HIV-infected patients, 59% were intravenous drug users, 31% were Haitian, 3% were homosexual males, 1% were perinatally-infected infants, and 6% did not have a known risk factor for HIV infection. Ninety-eight percent of the HIV-infected patients were black (84%) or hispanic (14%). The HIV-infected patients were more likely than the control patients to have either disseminated, genitourinary, intra-abdominal, mediastinal, or concurrent pulmonary TB. Fever was nearly universal among the HIV-infected patients, but was absent in about one-third of the control patients. Among untreated HIV-infected patients, disease progression was rapid and nearly always fatal. Among HIV-infected patients who received treatment, the response to therapy, as judged by hospital survival and time to defervescence, was similar to that of the control patients. Despite the extensive tuberculous dissemination among the HIV-infected patients, the diagnosis of TB was difficult and often delayed. In addition to the decrease in tuberculin reactivity and the atypical chest radiograph patterns, there was a need to consider other HIV-related infections in the differential diagnosis. Although sputum specimens grew M. tuberculosis in greater than 90% of the HIV-infected patients in whom they were obtained, sputum AFB stains were positive in less than 50%. Blood and urine specimen cultures were positive in 56% and 77% of the HIV-infected patients in whom these specimens were obtained, but did not provide a means of early diagnosis. Cerebrospinal fluid and pleural fluid were abnormal in nearly all patients with involvement of these sites but were rarely AFB-positive and were, therefore, only suggestive of TB. Procedures such as biopsies and aspirates of peripheral lymph nodes, visceral lymph nodes, liver, and bone marrow provided the highest immediate diagnostic yields with rates between 50% and 90%. These procedures must be considered early in the course of illness in HIV-infected patients with suspected extrapulmonary TB due to the rapidly progressive nature of this often fatal but usually treatable infection.     

Number of sputum cultures by MGIT system needed to diagnose pulmonary tuberculosis

PURPOSE: To study the number of sputum cultures by MGIT system (Becton-Dickinson) needed to diagnose pulmonary tuberculosis. OBJECT AND METHOD: Prospective study of all patients who visited our hospital, and were strongly suspected of pulmonary tuberculosis during the period from Jan. 2002 to Sept. 2003. In these patients, 3 consecutive sputum cultures were done by both MGIT-system and egg-based Ogawa medium (1 slant). RESULTS: Altogether 290 cases of sputum-culture positive pulmonary tuberculosis were available for analysis. In 210 first-sputum-smear positive cases, incremental yield of 3rd sputum culture in 3 consecutive MGIT cultures was equal to or less than 1.0% and 98.1% of culture positive cases were detected by 2 consecutive MGIT cultures. In 80 first-sputum-smear negative cases, incremental yield of 3rd sputum culture in 3 consecutive MGIT cultures was equal to or more than 5.0%, and 90.0% of culture positive cases were detected by 2 consecutive MGIT cultures. This detection rate was almost the same as the calculated detection rate (91.4%) by 3 consecutive Ogawa (2 slant) cultures (previous standard method). CONCLUSION: It was suggested that 2 consecutive sputum cultures by MGIT were sufficient to detect M. tuberculosis in first-sputum-smear positive cases, but 3 consecutive sputum cultures by MGIT were relatively useful in first-sputum-smear negative cases.     

Evaluation of suspected tuberculous pleurisy: clinical and diagnostic findings in HIV-1-positive and HIV-negative adults in Uganda.

SETTING: National Tuberculosis Treatment Centre, Mulago Hospital, Kampala, Uganda. OBJECTIVES: To compare clinical and radiographic presentation, and diagnostic methods, in adults with tuberculous pleurisy who are negative and positive for the human immunodeficiency virus (HIV). DESIGN: Adults with suspected pleural tuberculosis were screened by clinical examination, thoracocentesis and closed pleural biopsy. Biopsy material was cultured on Middlebrook 7H-10 solid medium and in BACTEC 12B radiometric vials. Pleural fluid was cultured using L?wenstein-Jensen slants, BACTEC and Kirchner liquid medium. RESULTS: Of 156 individuals enrolled, 142 had tuberculosis, of whom 80% were HIV-positive. Among those with tuberculosis, HIV-positive patients bad a more severe and longer illness. The size of effusions was similar in HIV-positive and HIV-negative patients. A higher proportion of HIV-positive patients had parenchymal infiltrates but this difference was not statistically significant. Pleural fluid lymphocytosis was present in all HIV-negative and 97% of the HIV-positive patients. HIV-positive patients had lower pleural fluid lymphocyte counts. Pleural fluid cultures were more often positive in HIV-positive patients. BACTEC and Kirchner liquid media gave higher yields than solid media. CONCLUSION: HIV-positive patients with tuberculous pleurisy had a more severe illness than HIV-negative patients. Mycobacterial cultures from HIV-positive patients were more often positive, suggesting more mycobacterial extension from the lungs into the pleural space. Liquid culture media were superior to solid media with regard to diagnostic yield and time until diagnosis.     

结核分枝杆菌/利福平耐药实时荧光定量核酸扩增检测技术诊断艾滋病患者肺结核的临床应用评价

目的:探讨结核分枝杆菌(Mycobacterium tuberculosis,MTB)/利福平耐药实时荧光定量核酸扩增检测(Xpert MTB/RIF)技术诊断艾滋病患者肺结核的应用价值。方法:回顾性分析2017年7月至2019年11月上海市(复旦大学附属)公共卫生临床中心收治的226例疑似肺结核的艾滋病患者的临床资料。分别进行痰涂片荧光染色显微镜下检查、BACTEC MGIT 960液体培养(或罗氏固体培养)和Xpert MTB/RIF检测,并分析在艾滋病患者中Xpert MTB/RIF技术诊断MTB感染和利福平耐药的灵敏度和特异度。结果:226例疑似肺结核患者中,痰培养阳性94例(41.6%),其中MTB阳性51例(54.3%),非结核分枝杆菌(nontuberculosis mycobacteria,NTM)阳性43例(45.7%)。以痰分枝杆菌培养阳性且结核分枝杆菌分泌蛋白64抗原阳性为金标准,Xpert MTB/RIF技术诊断MTB的灵敏度为72.6%[95%可信区间(confidence interval,CI)66.7%~78.4%],特异度为97.1%(95%CI 95.0%~99.3%)。Xpert MTB/RIF技术诊断痰涂片阳性患者MTB的灵敏度为76.7%(95%CI 67.7%~85.8%),特异度为90.0%(95%CI 83.6%~96.5%)。Xpert MTB/RIF技术诊断痰涂片阴性患者MTB的灵敏度为50.0%(95%CI 41.8%~58.2%),特异度为99.3%(95%CI 97.9%~100.0%)。18例患者同时检测利福平表型和基因型耐药,以表型耐药为金标准,Xpert MTB/RIF技术检测利福平基因型耐药的灵敏度为75.0%,特异度为100.0%。结论:艾滋病患者中Xpert MTB/RIF技术诊断肺结核的灵敏度和特异度均较高,且能快速区分MTB和NTM,具有较好的应用价值。     

HIV infection in patients with tuberculosis in Kinshasa, Zaire

To better define the interrelationship of infection with human immunodeficiency virus (HIV) and tuberculosis (TB), we conducted three HIV serosurveys of inpatients and outpatients with confirmed or suspected TB in Kinshasa, Zaire. HIV seroprevalence in hospitalized sanatorium patients did not change significantly in serosurveys conducted in 1985 and 1987 (92/231 [40%] versus 85/234 [36%]). These proportions were significantly higher than the 17% HIV seroprevalence observed in a 1987 serosurvey of 509 consecutive patients with an initial diagnosis of pulmonary TB seen at an outpatient TB diagnostic center in Kinshasa (p less than 0.001). HIV seroprevalence was higher in sanatorium patients with extrapulmonary TB (22/46 [48%]) and suspected pulmonary TB (60/132 [45%]) than in patients with bacteriologically confirmed pulmonary TB (94/287 [33%]) (p less than 0.02). Mycobacterium sputum isolation rates were similar in HIV-seropositive (28/34 [82%]) and HIV-seronegative patients (135/159 [85%]). All isolates were Mycobacterium tuberculosis. Eighteen (21%) of 84 HIV-seropositive sanatorium patients in 1987, who were followed for two months after admission, had died, compared with 11 (9%) of 128 HIV-seronegative patients (p less than 0.01). However, clearance rates of acid-fast bacilli from sputum after standard therapy were equally good in HIV-seropositive and HIV-seronegative survivors. With the growing AIDS problem, the serious TB burden in sub-Saharan Africa may become even more onerous and may critically overload the stressed African health care systems.     

Bronchoscopy and transbronchial biopsy in evaluation of patients with suspected active tuberculosis

To assess the value of fiberoptic bronchoscopy and transbronchial biopsy for evaluating patients suspected of having tuberculosis, we reviewed the records of 56 patients (1974–1980). All patients (1) were clinically suspected of having active tuberculosis; (2) had an abnormality on chest roentgenogram consistent with tuberculosis; (3) had an absence of acid-fast bacilli on three sputum smears or an inability to produce sputum; (4) had undergone fiberoptic bronchoscopy and transbronchial biopsy. The evaluations included fiberoptic bronchoscopy with collection of bronchial washings and brushings, and transbronchial biopsy and postbronchoscopy sputum specimens. Thirteen patients subsequently underwent percutaneous needle aspiration and one underwent thoracotomy.

Evaluations were diagnostic in 29 of the 56 patients (52 percent). Diagnoses were mycobacterial infection in 22 (39 percent) and other disease processes in seven (13 percent). Fiberoptic bronchoscopy and transbronchial biopsy provided a diagnosis when sputum cultures obtained before bronchoscopy were negative for Mycobacteria in 11 (20 percent) patients. Immediate diagnoses were made from microscopic specimens obtained from 11 of 23 (48 percent) fiberoptic bronchoscopy and transbronchial biopsy procedures on patients with previously undiagnosed mycobacterial infection. Transbronchial biopsy had the best yield for a microscopic diagnosis. On culture, bronchoscopy specimens had a lower yield (10 of 23 or 44 percent) than sputum specimens obtained before bronchoscopy (14 of 21 or 67 percent) probably due to the inhibition of mycobacterial growth by tetracaine. Of the patients in whom evaluation proved nondiagnostic, 17 of 27 were lost to follow-up; therefore, a definitive statement regarding the number of false negative evaluations is not possible.

Fiberoptic bronchoscopy and transbronchial biopsy (FFB/TBB) is a useful procedure in evaluating patients with negative smears who are clinically suspected of having tuberculosis. It can improve the ability to document active tuberculosis, provide a sensitive means of making an immediate diagnosis, and uncover other disease processes presenting like tuberculosis.