Bronchoalveolar lavage (BAL) studies are useful

to assess the lower respiratory tract inflammation and to

study the pathogenesis of various lung diseases (1). Even

though potent chemotherapeutic regimens are available

currently to treat patients with pulmonary tuberculosis,

radiographic and pulmonary function abnormalities persist

in a proportion of tuberculosis patients despite treatment

(2). Evaluation of lung immune process in pulmonary

tuberculosis using BAL may aid in understanding

the mechanism of lung injury and fibrosis which, in turn,

may help to formulate modalities of treatment that prevent

fibrosis. In addition, since BAL samples the epithelial

lining fluid of the alveoli, it is possible that it may aid

in early diagnosis of sputum smear negative pulmonary

tuberculosis

Vijayan, V K

NIRT Institutional Repository

EDITORIALBRONCHOALVEOLAR LAVAGE STUDIES INPULMONARY TUBERCULOSISVK VIJAYANCardio-Pulmonary Medicine,TRC, ICMR, Chennai 600 031Bronchoalveolar lavage (BAL) studies are usefulto assess the lower respiratory tract inflammation and tostudy the pathogenesis of various lung diseases (1). Eventhough potent chemotherapeutic regimens are availablecurrently to treat patients with pulmonary tuberculosis,radiographic and pulmonary function abnormalities per-sist in a proportion of tuberculosis patients despite treat-ment (2). Evaluation of lung immune process in pulmo-nary tuberculosis using BAL may aid in understandingthe mechanism of lung injury and fibrosis which, in turn,may help to formulate modalities of treatment that pre-vent fibrosis. In addition, since BAL samples the epithe-lial lining fluid of the alveoli, it is possible that it may aidin early diagnosis of sputum smear negative pulmonarytuberculosis.Studies on pathogenesisBAL studies in 27 sputum smear negative but ra-diographic probable pulmonary tuberculosis patients,confirmed as active pulmonary tuberculosis by isolationof Mycobacterium tuberculosis in culture from sputum and/or lavage specimens, had shown that two distinctcell profiles could be identified in smear negative pulmo-nary tuberculosis patients (3). One group (macrophagepredominant) had significantly elevated total cells andalveolar macrophages in both radiologically normal andabnormal lobes. The other group (lymphocyte predomi-nant) had expanded numbers of total cells, lymphocytesand granulocytes in radiologically abnormal lobe only.Sputum smear positive pulmonary tuberculosis patientshad been shown to have lymphocytosis in BAL fluid (4-7). In addition, eosinophilic pneumonia was also demon-strated in three bacteriologically confirmed pulmonary tu-berculosis (8). In two patients, pulmonary eosinophiliawas present only at the site of lesion and the third hadeosinophilia in both peripheral blood and lung. There wascomplete elimination of eosinophilic inflammatory processin two patients who had successfully completed antitu-berculosis treatment (8). BAL studies in miliary tubercu-losis show lymphocytic alveolitis (9,10). Elevated levelsof immunoglobulins (IgG, IgA, IgM) and fibronectin weredemonstrated in BAL fluid from patients with miliary tu-berculosis (10). Lymphocytic alveolitis (9,10,) and raisedimmunoglobulins (IgG and IgA) persisted in BAL fluid de-spite treatment (10).Alveolar macrophages from patients with activepulmonary tuberculosis produced significantly higher hy-drogen peroxide (11). Alveolar macrophages that wereresistant to OK la (anti-DR monoclonal antibody andcomplement treated) in fact produced increased levelsof hydrogen peroxide (12). Alveolar lining material of pa-tients with active pulmonary tuberculosis has less bac-tericidal activity against bacterial infections such asStaphyococcus aureus (13). It had also been demonstratedthat there was increased production of procoagulant ac-tivity by alveolar macrophages, in collaboration with lym-phocytes and other cells at the site of tuberculosis le-sions and this may lead to fibrin formation (14). It hadbeen reported that a decreased CD4/CD8 ratio with anincrease in CD8 cells in the alveolar space was associ-ated with slow disease regression in patients with activepulmonary tuberculosis suggesting that the balance of Tlymphocyte subsets may play a central role in the modu-lation of host defence against mycobacterial infection (15).Further studies utilizing BAL in patients with pulmonarytuberculosis with or without HIV infection are required tounderstand the local immune mechanisms which mayaid in formulating treatment modalities especially for pre-vention of lung fibrosis.Studies on diagnostic utilityPatients with positive tuberculin skin tests andabnormal chest radiographs compatible with tuberculo-sis pose diagnostic problems and therapeutic dilemma(to treat or not to treat for tuberculosis) to chest Physi-cians. Fibreoptic bronchoscopic studies provide varioustypes of specimens (aspirates, brushes, lavage fluidsand biopsies) for early diagnosis of sputum smear nega-tive pulmonary tuberculosis (16-22).In a retrospective review of patients over a six-year period, Baughman et al (23) observed thatbronchoscopy with BAL was useful in the diagnosis ofpulmonary tuberculosis. In their study there were 30 pa-tients whose pre-bronchoscopy expectorated sputumsmaples were negative for acid fast bacilli (AFB). Of these630, bronchoscopy specimens were smear positive in 26(87%). Only nine (30%) had sputum culture positivity. Inanother study (24), out of a total of 71 suspected patients,sputum culture was positive in 33 (46.5%) while BAL cul-ture was positive only in 24 (34%) patients and in whomsputum cultures were also positive. In none of the pa-tients, tuberculosis was diagnosed by BAL culture alone,despite BAL specimens were cultured in several differ-ent media. Lavage smear positivity enabling a rapid di-agnosis was possible in three (9%) of 33 patients provedto be tuberculosis by culture examination (24). Thus, asingle bronchoscopic procedure such as BAL fluid ob-tained by instillation of normal saline and cultured forM. tuberculosis is not, therefore, superior to sputum cul-ture examination for the diagnosis of sputum smear nega-tive, X-ray positive pulmonary tuberculosis. Kennedy etal had reported in a retrospective analysis of 112 pa-tients that 91% of prebronchoscopy sputum samples (allsmear negative) had positive culture results, but only 63%of BAL specimens were positive for M. tuberculosis (25).Sputum smear negative pulmonary tuberculosis is apaucibacillary condition and the dilution of epithelial lin-ing fluid by the instilled saline might be responsible forthe low yield from BAL specimens. In addition, the localanesthetic used for bronchoscopy might have also sup-pressed the growth of M. tuberculosis (26). In childhoodpulmonary tuberculosis, Somu et al found that gastriclavage was superior to BAL fluid for isolation ofM. tuberculosis in culture (27).Kennedy et al (25) had further observed that earlydiagnosis of sputum smear negative pulmonary tubercu-losis was possible in 38% of patients if differentbronchoscopic procedures such as transbronchial biopsy(TBB) and post-bronchoscopy sputum in addition to BALwere studied. Panda et al reported that immediate diag-nosis was possible in 35% of patients using TBB andbronchoscopy lavage (28). Chasroenratankul et al alsofound that the diagnostic yield of overall bronchoscopicprocedures (BAL smear and culture and TBB) was 32.5%in patients with suspected smear negative pulmonarytuberculosis (29). Thus an early diagnosis of tuberculo-sis is possible if different bronchoscopic procedures areemployed instead of a single procedure alone duringbronchoscopy. In a decision analysis model to assessthe overall utility of BAL in clinically suspected sputumsmear negative pulmonary tuberculosis, it has been sug-gested, in a region of high tuberculosis prevalence, em-pirical treatment is the best course of action. BAL in suchcircumstance can be reserved for further investigation ofPatients not responding to empirical antituberculosis treat-ments (30).2.3.4.5.6.7.8.9.10.11.12.13.14.Lung India (1997), XV, No.1 (P. 5-7)REFERENCESCrystal RG, Bitterman PB, Rennard SI, Hance AJ and KeoghBA. Interstitial lung diseases of unknown cause. Disorderscharacterized by chronic inflammation of the lower respira-tory tract. N Engl J Med 1984; 310: 154-65, 235-44.Wilcox PA and Ferguson AD. Chronic obstructive airwaysdisease following treated pulmonary tuberculosis. Respira-tory Med 1989; 83: 195-8.Vijayan VK, Sankaran K, Venkatesan P and Prabhakar R. Char-acterization of lower respiratory tract inflammation in patientswith smear negative pulmonary tuberculosis. Lung India 1994;12: 63-68.Dhand R, De A, Ganguly NK, Gupta N, Jaiswal S, Malik SKand Kohli KK. Factors influencing the cellular response inbronchoalveolar lavage and peripheral blood of patients withpulmonary tuberculosis. Tubercle 1988; 69: 161-73.Baughman RP, Dohn MN, London RG and Trame PT.Bronchoscopy with bronchoalveolar lavage in tuberculosisand fungal infections. Chest 1991; 99: 92-7.Ozaki T, Nakahira S, Tani K, Ogushi F, Yasuoka S and OguraT. Differential cell analysis in broncho-alveolar lavage fluidfrom pulmonary lesions of patients with tuberculosis. Chest1992; 102: 54-9.Ainslie GM, Soloman JA and Bateman. Lymphocyte and lym-phocyte subset numbers in blood and in bronchoalveolarlavage and pleural fluid in various forms of human pulmonarytuberculosis at presentation and during recovery. Thorax 1992;47: 513-8.Vijayan VK, Reetha AM, Jawahar MS, Sankaran K andPrabhakar R. Pulmonary eosinophilia in pulmonary tuberculo-sis. Chest 1992; 10: 1708-9.Vijayan VK, Jawahar MS, Reetha AM and PrabhakarR. Persisting alveolitis in miliary tuberculosis despite treatmentwith short-course chemotherapy. Indian J Chest Dis All Sci1990; 32: 49-53.Sharma SK, Pande JN, Singh YN, Verma K, Kathait SS, KhareSD and Malaviya AN. Pulmonary function and immunologicabnormalities in miliary tuberculosis. Am Rev Respir Dis 1992;145: 1167-1171.Selvaraj P, Rajiswamy, Vijayan VK, Prabhakar R and NarayananPR. Hydrogen peroxide producing potential of alveolar mac-rophages and blood monocytes in pulmonary tuberculosis.Indian J Med Res 1988; 88: 124-129.Selvaraj R, Rajiswamy, Vijayan VK, Prabhakar R and NarayananPR. Hydrogen peroxide release by OKlal (anti DR-mono-clonal antibody) resistant alveolar macrophages in tuberculo-sis. Indian J Chest Dis & All Sci 1989; 31: 141-149.Selvaraj R, Venkataprasad N, Vijayan VK, Narayanan PR. Al-tered bactericidal activity against Staphylococcus aureus intuberculous bronchoalveolar lavage fluids. Eur Respir J 1994;7: 121-126.Selvaraj P, Venkataprasad N, Vijayan VK, Prabhakar,Narayanan PR. Procoagulant activity of bronchoalveorlavage fluids taken from the site of tuberculous lesions. ERespir J 1994; 7: 1227-1232.Vijayan VK: BAL in Pulmonary TB15.16.17.18.19.20.21.22.23.Yu C-T, Wang C-H, Huang T-J, Lin H-C and Kuo H-P Relationof bronchoalveolar lavage T lymphocyte subpopulations torate of regression of active pulmonary tuberculosis. Thorax1995, 50: 869-874.Dener SJ and Bower VS: Diagnosis of pulmonary tuberculosisby flexible fibreoptic bronchoscopy. Am Rev Respir Dis. 1979;119: 677-79.Kvale PA, Johnson MC and Wroblewski DA: Diagnosis oftuberculosis Routine cultures of bronchial washings are notindicated. Chest 1979; 76: 140-42.Jett JR, Cortese DA and Dines DE. The value of bronchoscopyin the diagnosis of mycobacterial disease: A five-year experi-ence. Chest 1981; 80: 575-78.Willcox PA, Benatar SR and Potgieter PD. Use of flexiblefibreoptic bronchoscope in diagnosis of sputum-negative pul-monary tuberculosis. Thorax 1982; 37: 598-600.Chawia R, Pant K, Jaggi OP, Chandrasekhar S and ThukralSS. Fibreoptic bronchoscopy in smear-negative pulmonarytuberculosis. Eur Resp J 1988; 1: 804-06.lshihara HF, Fukaura A, Kashima N, Tazawa H, Nakajima H,Ide H and Takahashi. Early diagonsis of tuberculosis byfibreoptic bronchoscopy. Tubercle and Lung Disease 1992;73: 167-69.Wallace JM, Dentsch AL, Harrell JH and Moses KM.Bronchoscopy and transbronchial biopsy in evaluation of pa-tients with suspected active tuberculosis. Am J Med 1981; 70:1189-94.Baughman RP, Dohn MN, Loudon RB and Frame PT.Bronchosocpy with bronchoalveolar lavage in tuberculosisand fungal infections. Chest 1991; 99: 92-97.24.25.26.27.28.29.30.7Vijayan VK, Paramasivan CN and Sankaran K. Comparison ofbronchoalveolar lavage fluid and sputum culture in the diagno-sis of sputum smear negative pulmonary tuberculosis. Ind JTub 1996; 43: 179-182.Kennedy DJ, Lewis, WP, Barnes PJ. Yield of bronchoscopyfor the diagnosis of tuberculosis in patients with humanimmunodeficiency virus infection. Chest 1992; 102: 1040-44.Conte BA, Lafert EG. The role of the topical anaesthetic agentin modifying bacteriologic data obtained by bronchoscopy.New Eng J Med 1962; 267: 957-60.Somu N, Swaminathan S, Paramasivan CN, Vijayasekaran D,Chandrabhooshanam A, Vijayan VK and Prabhakar R. Valueof bronchoalveolar lavage and gastric lavage in the diagnosisof pulmonary tuberculosis in children. Tubercle and Lung Dis1995; 76: 295-299.Panda BN, Rajan KE, Jena J, Nema SK, Murali M and PatelAP. Diagnostic yield from flexible fibreoptic bronchoscopy insputum negative pulmonary tuberculosis cases. Ind J Tub1995; 42: 207-209.Chasroenratankul S, Dejsomritrutat W and Chaipraser A. Di-agnostic role of fibreoptic bronchoscopy in suspected smearnegative pulmonary tuberculosis. Respir Med 1995; 89: 621-23.Mohan A, Pande JN, Sharma SK, Rattan A, Guleria R andKhilnani GC. Bronchoalveolar lavage in pulmonary tuberculo-sis. A decision analysis approach. Quart J Med 1995; 88:269-276.

Bronchoalveolar lavage studies in pulmonary tuberculosis (editorial)

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Bronchoalveolar lavage studies in pulmonary tuberculosis (editorial)

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