Bronchoscopic aspiration and bronchoalveolar lavage in the diagnosis of sputum smear-negative pulmonary tuberculosis

The ability to make a definitive diagnosis in sputum smear-negative pulmonary tuberculosis by bronchoscopic aspiration, bronchoalveolar lavage (BAL), and examination of postbronchoscopy sputum were compared. Thirty-four patients with lesions on chest x-rays suspected of being pulmonary tuberculosis were entered into the study. The diagnosis of pulmonary tuberculosis was subsequently confirmed in 28 patients and the method of arriving at the final diagnosis was analyzed. A positive acid-fast bacilli (AFB) smear result was obtained in 4/28 (14%) of cases by a combination of bronchoscopic techniques and postbronchoscopy sputum examination. Prebronchoscopy sputum culture was positive in 12/28 (43%). Combined with bronchoscopy specimens, a positive AFB culture result was obtained in 26/28 (93%). Sputum examination, bronchoscopic aspiration, and BAL are complementary techniques and together they give a high yield of definitive diagnosis of pulmonary tuberculosis.     

Bronchoscopic aspiration and bronchoalveolar lavage in the diagnosis of sputum smear-negative pulmonary tuberculosis

The ability to make a definitive diagnosis in sputum smear-negative pulmonary tuberculosis by bronchoscopic aspiration, bronchoalveolar lavage (BAL), and examination of postbronchoscopy sputum were compared. Thirty-four patients with lesions on chest x-rays suspected of being pulmonary tuberculosis were entered into the study. The diagnosis of pulmonary tuberculosis was subsequently confirmed in 28 patients and the method of arriving at the final diagnosis was analyzed. A positive acid-fast bacilli (AFB) smear result was obtained in 4/28 (14%) of cases by a combination of bronchoscopic techniques and postbronchoscopy sputum examination. Prebronchoscopy sputum culture was positive in 12/28 (43%). Combined with bronchoscopy specimens, a positive AFB culture result was obtained in 26/28 (93%). Sputum examination, bronchoscopic aspiration, and BAL are complementary techniques and together they give a high yield of definitive diagnosis of pulmonary tuberculosis.     

Detection of Mycobacterium tuberculosis in bronchoalveolar lavage from patients with sputum smear-negative pulmonary tuberculosis using a polymerase chain reaction assay

Abstract The objective of this study was to evaluate the utility of a polymerase chain reaction (PCR) assay in detecting Mycobacterium tuberculosis in bronchoalveolar lavage (BAL) specimens of patients suspected of having active pulmonary tuberculosis (TB) but who were sputum smear-negative. Patients undergoing investigation for suspected pulmonary TB at the University Hospital, Kuala Lumpur, and who were sputum smear-negative underwent fibreoptic bronchoscopy and BAL. One portion of each lavage specimen was submitted for smear examination for acid-fast bacilli and mycobacterial culture and the other portion assayed by PCR for the presence of a 562-base pair DNA segment belonging to the insertion sequence IS986, unique to the M. tuberculosis complex. As controls, lavage specimens from patients with other lung lesions were also similarly tested. The PCR assay gave a positivity rate of 80.9% (55 of 68) compared with 8.8% of smear examination and 7.4% of culture for detecting M. tuberculosis in BAL specimens. The assay was positive in two of 45 BAL specimens from 35 control subjects. The PCR assay was more sensitive than smear and culture in detecting M. tuberculosis in BAL specimens of patients with sputum smear-negative pulmonary TB.     

Fibreoptic bronchoscopy in the diagnosis of sputum smear-negative pulmonary tuberculosis: current status

Sputum smear-negative pulmonary tuberculosis (SSN-PTB) is a common problem faced by clinicians. Performing fibreoptic bronchoscopy (FOB), and subjecting the bronchoscopic secretions/transbronchial lung biopsy (TBLB) material to conventional diagnostic methods of smear, mycobacterial culture and histopathology appears to be helpful in the diagnosis of SSN-PTB. Application of polymerase chain reaction (PCR) may be helpful as an adjunctive method in the appropriate clinical setting. The FOB facilitates rapid diagnosis and offers the additional advantage of the diagnosis of several conditions that may mimic PTB. However, FOB is an invasive procedure, and is associated with the risk of transmission of tuberculosis (TB) and other infections. It is costly, and is not widely available in the developing countries. In developed countries with no limitations on resources, early FOB seems to be the best course of action in a patient with suspected SSN-PTB. In resource-poor settings, where transmission of TB is high, sputum induction with hypertonic saline can be useful in adding to the diagnostic yield. If the TB suspect still remains induced sputum smear-negative, and if the pre-test probability of the patient having PTB is high, starting antituberculosis treatment (ATT) and closely monitoring the patient and reserving FOB to those patients who do not seem to improve/deteriorate or those who have a negative spontaneously expectorated/induced sputum culture (if performed and available) seems to be a practically useful approach. Proper precautions must be followed to disinfect the bronchoscope in between use so as to minimise the risk of nosocomial transmission of infection.     

The diagnosis of smear-negative pulmonary tuberculosis: the practice of sputum smear examination in Malawi.

SETTING: Forty hospitals in Malawi (3 central, 22 district and 15 mission) performing smear microscopy and registering tuberculosis patients. OBJECTIVE: To determine, in patients aged 15 years or above, 1) the proportion with smear-negative pulmonary tuberculosis (PTB) who had sputum smears examined, 2) the number of sputum smears examined per patient, and 3) the proportion of patients registered with smear-positive and smear-negative PTB. DESIGN: Data collection during three 6-month periods, from January 1997 to June 1998, using tuberculosis registers, laboratory sputum registers and quarterly reports. RESULTS: Of 6301 smear-negative PTB patients, 84% had sputum smears examined, the rate increasing from 76% in January-June 1997, to 85% in July-December 1997, to 89% in January-June 1998. Of patients who submitted sputum (where the number of smears was recorded), 99% had two or more smears examined and 93% had three smears examined. In district and mission hospitals performance improved over time, while in central hospitals results were more variable. During the same 18-month period 21 422 patients aged 15 years or more were registered with PTB: 59% with smear-positive PTB and 41% with smear-negative PTB; this pattern was similar in each 6-month period. CONCLUSION: The study suggests that it is reasonable to aim for a target of 90% or more of smear-negative PTB patients having sputum smears examined.     

Combined bronchoalveolar lavage and polymerase chain reaction in the diagnosis of pulmonary tuberculosis in smear-negative patients.

SETTING: The polymerase chain reaction (PCR) may be sensitive and specific for the diagnosis of tuberculosis, but most reports are of studies conducted in well-controlled laboratories. A study to evaluate the clinical value of bronchoalveolar lavage (BAL) combined with PCR was necessary. OBJECTIVE: One hundred and thirty one patients were recruited into the study from March 1994 to February 1997. DESIGN: Patients with a positive acid-fast stain on sputum smear were recruited into group A as positive controls, patients with lung cancer and a negative acid-fast stain on sputum smear were put into group B as negative controls, and patients who had clinical symptoms of pulmonary TB without sputum or with negative smear results were the investigating group. PCR was performed on the sputum samples from group A and B patients and on the BAL fluid from those in group C. RESULTS: The sensitivity of PCR was 96% in group A, and the specificity was 100% in group B. The sensitivity of PCR in the BAL fluid from the group C patients was 36% and the specificity was 96%; the positive predictive value was 94% and the negative predictive value was 45%. CONCLUSION: BAL plus PCR is useful in the rapid diagnosis of pulmonary TB in non-productive or smear-negative patients.     

两种试验对菌阴肺结核诊断价值的比较

目的比较酶联免疫斑点试验(T-SPOT.TB)与结核菌素试验(PPD)在菌阴结核诊断中的诊断效果和价值。方法我院收治的菌阴肺结核患者60例为菌阴肺结核组,同期收治经相关检查及治疗后排除结核感染的肺炎患者52例为肺炎组,两组患者年龄、性别构成等一般资料无显著性差异。分别采用T-SPOT.TB试验与PPD试验检测比较诊断效果。结果 60例菌阴肺结核患者采用T-SPOT.TB检测,阳性56例,敏感性为93.33%(56/60),与采用PPD检测(敏感性为71.67%,43/60)比较,P0.01。52例肺炎患者TSPOT.TB检测4例阳性,特异性为92.31%(48/52),与PPD检测(特异性67.31%,35/52)比较,P0.01。结论 T-SPOT.TB检测在菌阴肺结核临床辅助诊断中具有较高的灵敏度及阴性预测值,其应用价值显著高于结核菌素试验检测。     

实时多聚酶链反应检测支气管分泌物在涂阴结核病快速诊断中的应用

背景:实时定量PCR技术在微生物包括分枝杆菌检测领域应用越来越广泛。目的:评价在痰标本涂片抗酸染色无法获得诊断信息时(如没有痰或痰涂片阴性),RT-PCR在结核病诊断中的作用。设计:我们分析了从2006年1月至2008年4月之间连续纳入的为诊断结核病而进行的支气管分泌物RT-PCR检测的病人。所有病人均接收了计算机断层扫描(CT)、支气管镜和组织活检确诊结核病,对收集的支气管分泌物进行了微生物学和RT-PCR检测。最终的确诊基于微生物学或临床病理学的标准。结果:有136例患者最终得到了诊断结果,其中77例(包括65例培养阳性病例)诊断为结核。RT-PCR在确诊病人中的阳性率是51.9%(40/77)。与支气管分泌物抗酸染色相比,更多的病人(20.8%)通过RT-PCR被检测出来(40比20,P<0.001)。结合支气管分泌物抗酸染色和RT-PCR,77例结核确诊病例中的44例(57.1%)在几天之内被确诊。结论:支气管分泌物的RT-PCR检测在涂阴或无痰结核病人的快速诊断中是一种有用的方法。     

酶联免疫斑点试验在菌阴肺结核诊断中的价值

目的探讨酶联免疫斑点检测技术(enzyme-linked immunospot assay,ELISPOT)(T-SPOT.TB)在菌阴肺结核诊断中的应用价值。方法应用T-SPOT.TB试剂盒对55例菌阴肺结核(A组)和36例其他肺部疾病(B组)患者的外周血中Mtb特异性T淋巴细胞进行检测,同时对两组患者进行PPD试验、血清结核抗体(Mtb-AB)检测。结果A组T-SPOT.TB的阳性率为89.1%(49/55),要明显高于B组的19.4%(7/36)(χ2=44.59,P<0.001)。在A组,T-SPOT.TB的阳性率要明显高于PPD试验[36.4%(20/55)]、Mtb-AB[52.7%(29/55)]及PPD试验+Mtb-AB的阳性率[23.6%(13/55)],(χ2=12.13,χ2=7.08,χ2=21.54,P值均<0.01)。T-SPOT.TB在B组中的阴性率为80.6%(29/36),较PPD试验[86.1%(31/36)]及Mtb-AB阴性(63.9%,23/36)和PPD+Mtb-AB检测方法的阴性率[88.9%(32/36)]经检验,差异无统计学意义(χ2=0.39,χ2=2.69,χ2=0.41,P值均>0.05)。结论T-SPOT.TB检测特异度和敏感度要优于PPD试验及Mtb-AB的检测,可用于菌阴肺结核的辅助诊断,具有一定的临床推广使用的价值。     

Role of bronchoalveolar lavage fluid and serum interleukin-27 in the diagnosis of smear-negative pulmonary tuberculosis

Background:To evaluate the value of interleukin (IL)-27 measured in serum and bronchoalveolar lavage fluid (BALF) for the diagnosis of smear-negative pulmonary tuberculosis (TB).Methods:This was a prospective study of patients planned to undergo bronchoscopy at Wuxi No.5 People''s Hospital between January 2017 and September 2018. The patients were grouped as the TB and control groups. BALF and serum IL-27 were measured by ELISA. Receiver operating characteristic (ROC) curves were used to assess the diagnostic value and calculate the optimal cutoff values.Results:There were 40 patients in the control group and 87 in the TB group. In the TB group, 20 had positive sputum smear results and 67 were negative. The area under the ROC curve (AUC) of BALF IL-27 for pulmonary TB was 0.897 (95% CI: 0.830–0.944) (P < .001). The AUC of serum IL-27 for pulmonary TB was 0.703 (95% CI: 0.616–0.781) (P < .001). In patients with negative sputum smear results, the AUCs of BALF IL-27 and serum IL-27 for pulmonary TB was 0.882 (95% confidence interval [CI]: 0.805–0.936) (P < .001) and 0.679 (95% CI: 0.601–0.782) (P < .001), respectively.Conclusions:BALF IL-27 can be used for the diagnosis of pulmonary TB, particularly in those with a negative sputum smear result. Serum IL-27 could be an auxiliary method for TB screening.     

Time between sputum examination and treatment in patients with smear-negative pulmonary tuberculosis.

The time between sputum examination and commencement of treatment in patients registered with smear-negative pulmonary tuberculosis (PTB) in four hospitals in Malawi was investigated. Information was obtained in 701 of 887 patients who were registered over a 12-month period between 1997 and 1998: 86% were started on treatment within 3 weeks of sputum examination, 14% were started after a 3-week interval and 6% after a 6-week interval. Such delays are unacceptable, for a number of reasons. Recommendations will go to programme staff to repeat sputum examination in PTB suspects with an abnormal chest radiograph whose negative sputum smears were examined more than 3 weeks previously.     

Diagnosis of sputum smear-negative forms of pulmonary tuberculosis by transthoracic fine-needle aspiration.

We reviewed 25 patients submitted to transthoracic fine-needle aspiration (TFNA) who had a final diagnosis of pulmonary tuberculosis. In all cases, bacteriological stains and cultures of sputum and bronchial washing had been performed before admission and were negative. According to the material obtained from the procedure, the aspirates were divided in three groups: diagnostic (Ziehl-Neelsen and/or culture positive, n = 8, 32%), suggestive (granulomatous inflammatory changes, n = 10, 40%) and inconclusive (nonspecific inflammatory changes, isolated giant cells and/or blood, n = 7, 28%). On chest X-ray, 12 patients had opacities with the greatest diameter not exceeding 4 cm. All aspirates in the diagnostic group were from patients with this type of lesion, while all the inconclusive aspirates belonged to patients with larger lesions. As complications, 1 patient needed thoracic drainage for pneumothorax and 3 patients had haemoptyses. Thus TFNA has a place in the diagnosis of suspected pulmonary tuberculosis when more simple methods have failed, and its effectiveness seems to be increased when the lesions do not exceed 4 cm in diameter.     

支气管肺泡灌洗液RNA恒温扩增检测涂阴肺结核的诊断价值

目的评价支气管肺泡灌洗液结核分枝杆菌RNA恒温扩增检测(simultaneous amplification and testing for Mycobacterium tuberculosis,SAT-TB)对涂阴肺结核的诊断价值。方法选取涂阴肺结核组(观察组)95例和非结核病组(对照组)67例共计162例,两组患者均行纤维支气管镜检查,留取支气管肺泡灌洗液行荧光定量PCR(FQ-PCR),RNA恒温扩增检测(SAT-TB),结核菌快速培养,计算BALF的SAT-TB对涂阴肺结核诊断的敏感度,特异度,阳性预测值,阴性预测值。结果 SAT-TB检测BALF对诊断涂阴肺结核的敏感度为53.7%,特异度为98.5%,阳性预测值为98.1%,阴性预测值为60.0%,BALF的SAT-TB检测在敏感度,特异度,阳性预测值,阴性预测值与FQ-PCR法相比较均无显著性差异(χ~2值分别为3.572,0.341,0.679,1.603,P值均0.05)。结论 BALF中SAT-TB检测在涂阴肺结核中的敏感度,特异度均较高,且检测快速,对涂阴肺结核的快速诊断具有较大的应用价值。     

Diagnostic value of gastric aspirate smear and polymerase chain reaction in smear-negative pulmonary tuberculosis

OBJECTIVE: The aim of this study was to determine the validity of acid-fast bacilli (AFB) smear and polymerase chain reaction (PCR) from gastric aspirates for the diagnosis of smear-negative pulmonary tuberculosis. METHODOLOGY: A cross-sectional study was conducted in a university hospital. One hundred and nine patients with suspected pulmonary tuberculosis in whom either sputum smears were negative or who were not producing sputum were recruited to the study. All patients underwent gastric aspiration after an overnight fast followed by standard fibreoptic bronchoscopy. Specimens were subjected to AFB smear, culture, and pathological examination. PCR was performed on culture filtrate after 1 week of incubation. RESULTS: Eight patients did not complete the follow-up schedule. Of the 101 patients with final outcomes, a diagnosis of pulmonary tuberculosis from microbiological evidence was established in 54 patients. The gastric aspirate smear, PCR, or either one of them was positive in 34, 30, and 39 tuberculosis patients, respectively. There were 13 false positive smears from 47 non-tuberculosis patients, with five resulting from non-tuberculous mycobacteria (NTM). The PCR was falsely positive in eight patients, five of whom had previous histories of tuberculosis. The overall sensitivity, specificity, positive predictive value, and negative predictive value of gastric aspirate examination by combined smear and PCR were 72, 58, 66, and 64%, respectively. CONCLUSIONS: Gastric aspiration is a useful tool for the diagnosis of smear-negative pulmonary tuberculosis warranting institution of antituberculosis treatment. Interpretation of the results should be cautious in those who have had tuberculosis in the past or who have been at risk for acquisition of NTM.     

Fiberoptic bronchoscopy for the rapid diagnosis of smear-negative pulmonary tuberculosis

ABSTRACT: BACKGROUND: This study was aimed to investigate the diagnostic value of fiberoptic bronchoscopy (FOB) with chest high-resolution computed tomography (HRCT) for the rapid diagnosis of active pulmonary tuberculosis (PTB) in patients suspected of PTB but found to have a negative sputum acid-fast bacilli (AFB) smear. METHODS: We evaluated the diagnostic accuracy of results from FOB and HRCT in 126 patients at Gangnam Severance Hospital (Seoul, Korea) who were suspected of having PTB. RESULTS: Of 126 patients who had negative sputum AFB smears but were suspected of having PTB, 54 patients were confirmed as having active PTB. Hemoptysis was negatively correlated with active PTB. Tree-in-bud appearance on HRCT was significantly associated with active PTB. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FOB alone was 75.9%, 97.2%, 95.3%, and 84.3%, respectively, for the rapid diagnosis of active PTB. The combination of FOB and HRCT improved the sensitivity to 96.3% and the NPV to 96.2%. CONCLUSIONS: FOB is a useful tool in the rapid diagnosis of active PTB with a high sensitivity, specificity, PPV and NPV in sputum smear-negative PTB-suspected patients. HRCT improves the sensitivity of FOB when used in combination with FOB in sputum smear-negative patients suspected of having PTB.     

肺泡灌洗液结核杆菌RNA和DNA检测在痰菌阴性肺结核诊断中的临床应用

目的观察肺泡灌洗液结核杆菌RNA和DNA检测在痰菌阴性肺结核患者中的阳性检出情况。方法选取2017年3月—2019年3月在我院接受检查和治疗且最终确诊为痰菌阴性肺结核的患者为研究对象,所有患者均接受肺泡灌洗液结核杆菌RNA和DNA检测。分析2种检测方法阳性检出率的差异。结果结核杆菌RNA阳性检出率为63.33%,DNA阳性检出率为33.33%,前者高于后者。结论结核杆菌RNA检测对痰菌阴性肺结核具较高灵敏度,优于DNA检测。     

Diagnosis of pulmonary tuberculosis by detection of tuberculostearic acid in sputum by using gas chromatography-mass spectrometry with selected ion monitoring

Tuberculostearic acid [(R)-10-methyloctadecanoic acid (TBSA)] is a structural component of mycobacteria, and its detection in appropriate clinical specimens has potential application as a rapid screening method for the presence of Mycobacterium tuberculosis and other mycobacteria. We used the highly sensitive technique of gas chromatography-mass spectrometry (GC-MS) combined with selected ion monitoring (SIM) of m/e 312 and m/e 167 for detecting TBSA in 405 clinical sputum specimens collected in Hong Kong, where tuberculosis is still common. TBSA was detected in 39 M. tuberculosis smear-positive, culture-positive specimens; 63 of 66 smear-negative, culture-positive specimens; and 1 of 300 smear-negative, culture-negative specimens. Thus, for screening of sputa from individuals with suspected pulmonary tuberculosis, the detection of TBSA by GC-MS/SIM is highly specific and more sensitive than conventional microscopy and more rapid but slightly less sensitive than conventional culture methods.     

Evaluation of the FASTPlaqueTB assay for direct detection of Mycobacterium tuberculosis in sputum specimens.

SETTING: Sputum samples were collected from suspected tuberculosis patients attending out-patient clinics at the Ojha Institute of Chest Diseases, Karachi, Pakistan. OBJECTIVE: To evaluate the performance of the FASTPlaqueTB assay for rapid diagnosis of pulmonary tuberculosis. DESIGN: A comparative study of 584 sputum samples using acid-fast smear microscopy, Lowenstein-Jensen culture and FASTPlaqueTB. RESULTS: A total of 514 samples yielded complete results. Seventy specimens were lost to analysis due to the overgrowth of contaminants. The addition of antimicrobials inhibited growth of gram-positive contaminants, and reduced the overall contamination rate from 18.2% to 7.2%. Mycobacterium tuberculosis was isolated from 175 smear-positive and 70 smear-negative specimens. FASTPlaqueTB detected M. tuberculosis in 81.6% of specimens, with a specificity of 97.7%. The sensitivity and specificity of the assay for smear-positive specimens were respectively 87.4% and 88.2%. For smear-negative specimens, the sensitivity of the assay was 67.1% and the specificity was 98.4%. The combined sensitivity of smear and FASTPlaqueTB for M. tuberculosis was 90%. Test results were available in 48 hours. CONCLUSION: FASTPlaqueTB is a sensitive and specific test for rapid diagnosis of pulmonary tuberculosis in high prevalence areas. The test is sensitive enough to confirm a large number of clinically suspected smear-negative cases and improve case finding.