The role of routine culture for tuberculosis during bronchoscopy examination of lung masses

BACKGROUND: Many centers routinely culture bronchoscopy samples for mycobacteria even when tuberculosis (TB) is not strongly suspected. The value of this practice has hardly been investigated. OBJECTIVE: The aim of this retrospective study was to assess the utility of routine culture of bronchoscopy samples of lung masses for mycobacteria in a region where TB is not endemic. PATIENTS AND METHODS: The study group consisted of 168 patients who underwent bronchoscopy for investigation of lung masses in a major tertiary-care, university-affiliated facility in central Israel. The findings on acid-fast bacillus staining and culture were reviewed, and data on demographic characteristics were collected from the files. RESULTS: There were 97 men (58%) and 71 women with a mean age of 62 +/- 25 years. One culture (0.6%) grew Mycobacterium tuberculosis. There were no cases of positive acid-fast bacillus smear or positive nontuberculous mycobacteria culture. Sixty USD (5.45%) would be saved per patient without clinical suspicion of TB. CONCLUSIONS: These findings highlight the need to formulate new guidelines for the performance of mycobacterial cultures of bronchoscopy specimens in areas with a low prevalence of TB.     

The value of fiberoptic bronchoscopy in diagnosis of smear negative pulmonary tuberculosis

Although mycobacterial culture positivity is the gold standard for the diagnosis, the initial approach to the diagnosis of pulmonary tuberculosis (PTbc) is the detection of acid-fast bacilli (AFB) in respiratory specimens as recommended by the World Health Organization. But the physicians have to make a decision for the patients whose sputum smears are negative or who can not produce sputum. Waiting for culture results with radiological follow up or empirical antituberculous therapy are the standard options. In our study we aimed to assess the diagnostic yield of fiberoptic bronchoscopy in patients, suspected to have tuberculosis, whose sputum smears were negative or who could not produce sputum. Fifty six patients who suspected to have PTbc with sputum smear negative were enrolled in the study (fiberoptic bronchoscopy and selective bronchial washings were done to all patients. Bronchial washings were obtained from the affected parts). Mucosal biopsies were done in patients in where endobronchial abnormalities were noted. Transbronchial biopsies were done in selected patients from the radiological localizations. Ziehl-Nielsen staining and culture in L?wenstein-Jensen medium were the microbiological studies. Typical granulomas were expected to detect on histopathologic examination. Bronchoscopic lavage smears were positive for Mycobacterium tuberculosis in 13 (23%) patients. Twenty eight (50%) patients had positive culture. Histopathological results confirmed tuberculosis in eight of 20 patients who had undergone mucosal biopsies, four of seven of transbronchial biopsies, two of three of needle aspiration biopsies. By bronchoscopic procedures early diagnosis was performed in 27 (48.21%) patients. We concluded that fiberoptic bronchoscopy has an important role in the diagnosis of patients suspected to have tuberculosis, whose sputum smears were negative or who could not produce sputum. It is useful and necessary in selected cases.     

Yield of bronchoscopy for the diagnosis of tuberculosis in patients with human immunodeficiency virus infection.

The efficacy of bronchoscopy for the diagnosis of tuberculosis in patients infected with human immunodeficiency virus (HIV) has not been systematically evaluated. We therefore compared the diagnostic yield of bronchoscopy in 67 HIV-infected and 45 non-HIV-infected patients with culture-proven pulmonary tuberculosis. In all cases, acid-fast smears of sputum were negative or not obtained prior to bronchoscopy. Prebronchoscopic sputum culture yielded Mycobacterium tuberculosis in 34 (89 percent) of 38 HIV-infected patients and 26 (93 percent) of 28 non-HIV-infected patients from whom specimens were obtained. Bronchoscopy provided an early diagnosis of tuberculosis (positive acid-fast smear or granulomata on biopsy) in 23 (34 percent) of the HIV-infected patients and 20 (44 percent) of the patients without HIV infection. The sensitivities of the acid-fast smear and of mycobacterial culture of bronchoscopic specimens and postbronchoscopic sputum were similar in patients with or without HIV infection. In HIV-infected patients, granulomatous inflammation was noted on transbronchial biopsy in 11 (19 percent) of 59 patients with HIV infection, compared to 16 (43 percent) of 37 patients without HIV infection (p = 0.01). Nevertheless, transbronchial biopsy provided the exclusive means for an early diagnosis of tuberculosis in six (10 percent) of 59 HIV-infected patients. We conclude that the yield of bronchoscopy for the diagnosis of pulmonary tuberculosis in HIV-infected patients is similar to that in patients without HIV infection, and that transbronchial biopsy provides incremental diagnostic information not available from evaluation of sputum or bronchoalveolar lavage fluid.     

抗酸染色对肺结核的诊断价值

目的 了解结核分枝杆菌抗酸染色对肺结核的诊断价值。方法对98例确诊为继发型肺结核和血行播散型肺结核患者,统计分析痰液及纤支镜刷检液涂片抗酸染色情况。结果98例中抗酸染色阳性38例,阴性60例。10例经纤支镜刷检液涂片抗酸染色中,阳性6例。结论抗酸染色是诊断肺结核的常规方法,纤支镜刷检液涂片明显高于痰涂片法。     

Diagnosis of tuberculosis: routine cultures of bronchial washings are not indicated.

During a five-year period, cultures of bronchial washings for Mycobacterium tuberculosis were obtained almost routinely (859 of 1,012 bronchoscopic examinations.). This practice proved costly, and the diagnostic yield was extremely low. Only three cases were diagnosed solely by this method (0.35 percent). Five other cases were false-positive. Additionally, 39 patients with known active pulmonary tuberculosis had false-negative cultures of bronchial washings; 13 of these 39 patients were receiving antituberculosis drugs at the time of their bronchoscopic examinations. The inhibitory effect of local anesthetics upon the growth of M tuberculosis is the possible cause for the remaining 26 false-negative cultures. We conclude that bronchoscopic examination and culture of bronchial washings are not the best sources for diagnosis of pulmonary tuberculosis and that cultures of sputum and/or gastric washings are usually sufficient. The practice of obtaining routine cultures of bronchial washings in known pulmonary tuberculosis is of questionable value, when nearly two-thirds may be false-negative.     

纤维支气管镜诊断支气管结核98例分析

目的　探索支气管结核的确诊手段及临床特征。方法　分析 98例支气管结核患者的临床表现及纤支镜结果。结果　主要症状包括咳嗽 72例 (73% ) ,咳痰、咯血、气喘、胸痛、发热等。纤支镜示 :支气管刷检结核菌阳性率 85 .71% ,组织活检阳性率 6 9.2 3% ,其中 4 1.84 %以炎性浸润改变为主 ,2 2 .4 5 %以溃疡型改变为主 ,11.2 3%以增殖改变为主 ,2 4 .4 9%以瘢痕狭窄改变为主。结论　当有支气管结核临床表现及 X线表现特异性不强时 ,进行纤支镜检查。当病理、细菌学均不能明确诊断 ,可进行试验性抗结核治疗 ,追踪观察以确诊     

纤支镜在菌阴肺结核中的应用评估

目的 观察纤支镜在菌阴肺结核诊断中的价值.方法 分析190例入院时痰涂片和PCR分析均为阴性疑诊为肺结核患者的病例资料,从经纤支镜抗酸杆菌涂片的阳性率、PCR检测结核分枝杆菌阳性率、上皮性肉芽肿支气管活检、结核分枝杆菌的培养阳性率等四个方面进行分析.结果 190例病例中,经纤支镜取样的阳性率:42.6％(痰涂片),63.6％(PCR分析),31.2％(肉芽肿支气管活检),54.2％(痰培养),将各种检查手段联合起来,诊断率可以达到85.2％.结论 经纤支镜取样有较高阳性率,可以提供快速明确的结核诊断.     

A ten-year experience with fiberoptic bronchoscopy for mycobacterial isolation. Impact of the Bactec system

From January 1974 to December 1983, positive mycobacterial isolates from all sources were reviewed to determine the impact of fiberoptic bronchoscopy (FB) on retrieval and identification of these organisms. There were 112 patients with positive cultures obtained during FB, 25 with Mycobacterium tuberculosis and 87 with mycobacteria other than tuberculosis (MOTT). We reviewed the results of prebronchoscopy and postbronchoscopy sputum specimens, bronchial washings, brushings, and transbronchial biopsy to determine the yield from each specimen in patients with M. tuberculosis. The bronchial washings provided positive cultures in 24 of 25 and were exclusively positive in 10 of 25 (40%). We also reviewed the clinical presentation, chest roentgenogram, bronchoscopy findings, and culture data for the 87 patients with MOTT isolated. The isolation of MOTT from bronchoscopy specimens increased throughout the study, most notably with the introduction of a rapid radiometric method (the Bactec system) for the recovery of mycobacteria to our laboratory in June 1983. Active disease could be established in only 13 of 87 cases (15%). Our findings confirm the sensitivity of Bactec in the isolation of MOTT from bronchoscopic specimens. The Bactec system, on the other hand, does not differentiate saprophytic colonization from clinical disease. To avoid expensive, time-consuming biochemical identification necessary to evaluate these MOTT isolates, careful selection of patients prior to obtaining mycobacterial cultures during FB is a critical factor.     

Bronchoscopy with bronchoalveolar lavage in tuberculosis and fungal infections

STUDY OBJECTIVE: To determine the utility of bronchoscopy with bronchoalveolar lavage for diagnosing M tuberculosis and fungal infections. DESIGN: Retrospective review of patients over a six-year period. SETTING: In- and outpatients of one University hospital and affiliated Veterans Administration Medical Center. PATIENTS: Those who were subsequently found to have either M tuberculosis or fungal infections. INTERVENTIONS: Bronchoscopy with bronchoalveolar lavage specimens were compared to prebronchoscopy sputum, when available. Specimens were sent for smear and culture for both acid-fast bacilli and fungi. In the case of lavage, an aliquot also was studied for cellular differential. MEASUREMENTS AND RESULTS: For TB, sputum was smear-positive in 6/47 (34 percent) and culture positive in 24/47 (51 percent), while bronchoscopy was smear positive in 34/50 (68 percent) and culture positive in 46/50 (92 percent). For fungal infections, no sputum was smear-positive and only 1/22 (5 percent) was sputum culture-positive, while bronchoscopy was smear-positive in 14/41 (34 percent) and culture positive in 35/41 (85 percent). Bronchoscopy washings and BAL provided complementary specimens. Eighty-three patients had adequate lavages and the cellularity was significantly different from controls (lymphocytes: TB 18 +/- 11.2 percent [mean +/- SD]; fungal: 13 +/- 11.1 percent; controls 6 +/- 3.1 percent; p less than 0.001; neutrophils: TB 9 +/- 11.5 percent; fungal: 6 +/- 9.1 percent controls: 2 +/- 1.5 percent, p less than 0.01); however, there was overlap and no pattern was characteristic for TB or fungal infections. CONCLUSION: Bronchoscopy with BAL is useful in diagnosing tuberculosis and fungal infections.     

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.     

Diagnostic role of fiberoptic bronchoscopy for mycobacterial diseases]

From 1981 to 1991, 5,572 patients underwent bronchoscopic examination, in this series 3,754 patient's samples were sent for determination of mycobacterial isolation. In the 506 samples, mycobacterial bacilli were detected with smear or culture. In the low tuberculous incidence area like northern part of America, many reporters supported the opinion that routine bronchial aspirate detection for tuberculosis was not cost-effective. Inversely, in the high tuberculous incidence area like Hong Kong, M. lp et al. claimed the usefulness of routine bronchial aspirate examination for mycobacterial bacilli. Japan was regarded as moderate tuberculous incidence area. We review a ten-year experience with fiberoptic bronchoscopy for mycobacterial isolation. Our results suggest that in an area with a moderate prevalence of tuberculosis, bronchoscopic examination for mycobacterial disease is useful in the selected hospitals for the selected cases. In Japan, the smear positive prevalence has been on the increase from 1982. We estimate that the Japanese popularization of fiberoptic bronchoscopy may influence a part of the Japanese epidemic statistical analysis of mycobacteriosis.     

69例支气管结核临床分析

目的　探索支气管结核早期确诊手段及临床特征。方法 分析69例经纤维支气管镜 (纤支镜 )确诊的支气管结核患者临床表现、胸部X线、CT及纤支镜结果。结果 69例主要症状包括:咳嗽68例,咳痰44例,午后低热50例,盗汗49例,乏力48例,喘息18例,痰中带血13例。胸片及CT示:气管开口凹凸不平、不规则狭窄42例,有阻塞性肺炎26例,肺不张25例,肺内空洞14例,肺门淋巴结肿大11例。痰涂片结核菌阳性率为43.5%,痰结核菌培养阳性率36.2%。纤支镜示:刷检结核菌阳性率为55.1%,组织活检中56.7%证实为结核,其中40.6%为炎症浸润型,13.0%为增殖型,29.0%为溃疡型,26.1%为狭窄闭塞型。上述四种类型发现结核菌的阳性率分别为71.4%,77.8%,100%和55.6%。结论 当有支气管结核临床表现时,应行胸部X线、CT检查,对可疑病人作纤支镜。当病理、细菌学均不能明确诊断,应重复活检、刷检和试验性抗结核治疗,追踪观察以确诊。     

胸片正常的支气管内膜结核15例临床分析

目的 探索胸片正常的支气管内膜结核的临床特征及早期确诊手段。方法 分析15例经纤维支气管镜(纤支镜)确诊的支气管内膜结核患者的临床表现、胸部X线(平片)及CT片、纤支镜检查结果。结果 15例中主要症状包括：咳嗽15例，气促5例，胸痛4例，发热3例，咯血2例，消瘦2例。15例的X线胸片正常。纤支镜检查示46．7％的病例有炎性浸润型病变，33．3％有增殖型病变，13．3％有溃疡型病变，6．7％有狭窄闭塞型病变。15例痰涂片行抗酸染色者中3例阳性，痰培养阳性1例；纤支镜刷片检查8例阳性，活组织检查7例证实为结核。结论 支气管内膜结核无特异性临床表现及胸部X线表现正常不能排除支气管内膜结核，确诊主要依靠纤支镜检查。对不明原因发热和呼吸道症状经积极治疗无效者，应怀疑支气管内膜结核而及时行纤支镜检查。通过镜下常规刷检找抗酸杆菌配合组织活检确诊率高。     

Unexpected pulmonary involvement in extrapulmonary tuberculosis patients

BACKGROUND: This study aimed to assess the utility of sputum examinations and chest radiographs (CXRs) in patients with extrapulmonary tuberculosis (XPTB) to detect pulmonary involvement of tuberculosis (TB). METHODS: We studied 72 XPTB patients who were managed through the TB Program, King County, WA, from January 2003 through November 2004. RESULTS: The two most common sites of XPTB were the lymph nodes (36 [50%]) and pleura (12 [17%]). Thirty-five of 72 XPTB patients (49%) had abnormal CXR findings. Sputum was not obtained from 15 patients despite sputum induction. Of the 57 patients from whom sputum was collected, 30 (53%) had abnormal CXR findings, 5 (9%) had sputum smears that were positive for acid-fast bacilli, and 12 (21%) had sputum cultures that were positive for Mycobacterium tuberculosis. Weight loss was significantly associated with positive sputum culture findings in a multivariate analysis (odds ratio, 4.3; 95% confidence interval, 1.01 to 18.72; p = 0.049). There was no significant difference in the occurrence of positive sputum culture results between patients with abnormal CXR findings and those with normal CXR findings (7 of 30 patients [23%] vs 5 of 27 patients [19%], respectively; p = 0.656). Of 24 HIV-negative XPTB patients with normal CXR findings, 2 patients (8%) had positive sputum culture findings. CONCLUSIONS: CXR results did not reliably differentiate XPTB patients with and without positive sputum culture findings. Some XPTB patients had positive sputum culture results despite normal CXR findings and negative HIV status. Weight loss in XPTB patients was associated with positive sputum culture results. Sputum examinations in XPTB patients, regardless of the CXR results, may identify potentially infectious cases of TB.     

The role of routine culture for tuberculosis during bronchoscopy in a nonendemic area: analysis of 300 cases and review of the literature

BACKGROUND: Many centers routinely culture bronchoscopy samples for mycobacteria, even when tuberculosis (TB) is not strongly suspected. The value of this practice is poorly defined in areas with a low prevalence of TB. METHODS: A retrospective observational study was conducted in tertiary care, university-affiliated medical center and included 300 consecutive patients who underwent a bronchoscopy examination. The findings for acid-fast bacillus (AFB) staining and culture were reviewed, and data on demographic characteristics, presenting symptoms, old TB, autoimmune status, and chest x-ray results were collected from the files. RESULTS: The study included 175 men (58%) and 125 women, with a mean age of 62 +/- 25 years. Eight cultures (2.67%) grew mycobacteria: 4 (1.33%) Mycobacterium tuberculosis and 4 (1.33%) nontuberculous mycobacteria (NTM). Thus, the incidence of TB was 4 of 300 (1.33%) patients. There were no cases of positive AFB smear or culture in patients with atelectasis, pulmonary mass, or hemoptysis with normal chest x-ray. One of the 22 patients (5%) with diffuse pulmonary nodules had active TB as did 3 of the 134 patients (2.24%) with pulmonary infiltrates. All 4 patients with NTM had pulmonary infiltrates. The use of a cost-effective diagnostic strategy in our series, wherein testing would have been ruled out for patients without a clinical suspicion of TB and radiologic findings of a pulmonary mass (n = 107, 35.6%), would have saved the system US $5350. CONCLUSION: The findings highlight the importance of an effective strategy for routine TB cultures during bronchoscopy in patients from nonendemic areas in whom TB is not suspected, especially those with pulmonary mass.     

支气管结核86例临床分析

目的探讨支气管结核(EBTB)的临床特征。方法分析经纤维支气管镜(纤支镜)确诊的86例EBTB患者的临床表现、胸部X线、纤支镜检查结果等。结果纤支镜检查示大致正常仅占9%,37%有炎症浸润型病变,16%有增殖型病变,26%有狭窄闭塞型病变,12%有溃疡型病变。78例痰涂片行抗酸染色中10例阳性,86例行纤支镜刷片检查69例阳性,62例行活组织检查者中24例证实为结核。结论EBTB缺乏特异性临床表现,确诊主要依靠纤支镜检查。     

肺结核合并支气管结核97例临床分析

目的探讨肺结核合并支气管结核的临床特点。方法回顾性分析97例肺结核合并支气管结核临床资料。结果临床以咳嗽(82.5%)、咳痰(80.4%)、发热(45.4%)、不同程度咯血或血丝痰(23.7%)等为主要症状,胸部CT以肺不张或膨胀不全(44.2%)及浸润增殖性病灶(37.9%)为主要表现,并可见支气管狭窄阻塞、支气管扩张、支气管播散、支气管充气征、纵隔淋巴结增大、纵隔淋巴结钙化等表现,痰涂片或培养检查抗酸杆菌阳性率较高(63.9%),尤其在多叶段浸润增殖病灶患者中其阳性率高达83.3%。纤支镜检查以主支气管及叶支气管开口受累显著(64.8%),多气管支气管受累患者达81.4%,且多种支气管镜下表现类型并存,纤支镜刷检抗酸杆菌、组织活检阳性率分别为55.9%、69.4%。接受纤支镜介入治疗的患者仅有18例,其中6例支气管狭窄闭塞并肺不张患者行气管镜下支气管球囊扩张术治疗,5例支气管狭窄好转。结论肺结核合并支气管结核患者临床表现无特异性。胸部CT对观察支气管损伤及淋巴结病变能提供较大帮助。气管镜检查仍为其重要诊断手段,镜下可见多气管支气管受累,且镜下表现类型相互重叠。球囊扩张术可有效改善支气管狭窄。     

The validity of acid-fast smears of gastric aspirates as an indicator of pulmonary tuberculosis.

SETTING: A tuberculosis referral hospital in Canada. OBJECTIVE: To determine the validity of acid-fast (AFB) smears of gastric aspirates (GA) in the diagnosis of pulmonary tuberculosis, and to assess the prevalence of nontuberculous mycobacteria (NTM) in GA isolates from such patients. DESIGN: A retrospective case review of our experience with AFB smears (Kinyoun) and cultures of GA and sputum over a 3-year period. RESULTS: From 1994 to 1996 inclusive, 1155 GA were performed in 889 patients. Mycobacteria were cultured from 109 (9%) GA. Thirteen of these were positive on smear (sensitivity 19%). All GA that were positive on smear were culture positive for Mycobacterium tuberculosis. There were no false positive smears (specificity 100%). The sensitivity and specificity of the sputum smear were 45% and 99%, respectively. Of the 96 culture positive, smear negative GA, 54 grew M. tuberculosis and 42 grew an NTM. Of 13 patients who had sputum and GA studied coincidentally, and in whom the sputum was both smear and culture positive, the GA culture was positive in 13 and the smear was positive in eight (66%). CONCLUSION: AFB smear of GA is a relatively insensitive but highly specific indicator of pulmonary tuberculosis warranting institution of antituberculosis treatment. Gastric AFB smear positivity appears to reflect a high bacillary burden within the respiratory tract.     

The role of bronchoscopy in the diagnosis of pulmonary tuberculosis in patients at risk for HIV infection.

The present study was undertaken to clarify the role of bronchoalveolar lavage (BAL) and transbronchial biopsy (TBB) in the diagnosis of pulmonary tuberculosis in patients at risk for human immunodeficiency virus (HIV) infection. We retrospectively identified 31 patients at risk for HIV who proved to have Mycobacterium tuberculosis on culture of at least one pulmonary specimen. All had pulmonary symptoms but initial sputum smears negative for acid-fast bacilli (AFB). All underwent fiberoptic bronchoscopy (FOB), including BAL and TBB; postbronchoscopy sputum was also collected in 19 patients. A specimen was considered to yield an immediate diagnosis when positive for AFB either on smear or histologic study; granulomas alone were considered positive when no other causes were identified. Overall, an immediate diagnosis was made by bronchoscopic specimens in 15 (48 percent) of 31 cases. TBB was the sole positive specimen in seven patients (23 percent). For comparison, similar specimens from 40 patients in whom M avium complex (MAC) grew on culture were also evaluated. An immediate identification of AFB was made in only four patients (10 percent). We conclude that the finding of AFB on staining of any pulmonary specimen is highly suggestive of tuberculosis, rather than MAC, and warrants institution of antituberculosis therapy. Of all bronchoscopic specimens, TBB provides the highest yield for an immediate diagnosis of tuberculosis.