Fluorescent microscopy and Ziehl–Neelsen staining of bronchoalveolar lavage, bronchial washings, bronchoscopic brushing and post bronchoscopic sputum along with cytological examination in cases of suspected tuberculosis.

Objectives: Ever since the discovery of Mycobacterium tuberculosis in 1882, many diagnostic methods have been developed. However “The gold standard” for the diagnosis of tuberculosis (TB) is still the demonstration of acid fast Bacilli (AFB) by microscopic examination of smear or bacteriological confirmation by culture method. Materials and Methods: In suspected 75 patients with active pulmonary TB, the materials obtained bronchoscopically, were bronchoalveolar lavage (BAL), bronchial brushings, bronchial washings and post bronchoscopic sputum. Four smears were made from each of the specimen. Fluorescent Staining, Ziehl–Neelsen (ZN), Pap and May Grunwald‑Giemsa (MGG) stains were carried out for cytological examination. Results: Fluorescent stain yielded maximum AFB positivity in all the methods, that is 36 (48%) in post fibre‑optic bronchoscopy (FOB) sputum and 19 (25.33%) by fluorescence microscopy in both bronchial brushings and bronchial washings. Maximum yield of AFB with ZN staining 12 (16%) was equal to the post FOB sputum and bronchial brushings samples. It was followed by 6 cases (8%) in BAL and 4 (5.3%) in bronchial washings. The cytological examination was suggestive of TB in only 8 (10.66%) cases in bronchial washings and 6 (8%) cases in post FOB collection. It was equal in BAL and Bronchial brushings each that is 5 (6.67%). Conclusion: Bronchoscopy is a useful diagnostic tool and fluorescent microscopy is more sensitive than ZN and cytology. On X‑ray examination, other diseases like malignancy or fungus can also mimick TB. So apart from ZN staining or fluorescence microscopy, Pap and MGG stain will be worthwhile to identify other microorganisms.

Role of fiberoptic bronchoscopy and utility of bronchial washings and brushings in the diagnosis of lung diseases.

Transbronchial lung biopsy via fiberoptic bronchoscope is an extremely useful technique by which bronchial as well as lung biopsies along with brushings and washings can be easily and safely taken.1 Fiberoptic bronchoscopy (FOB) was performed and biopsies were done in 250 patients. In addition, bronchial brushings and washings were also taken in 140 and 115 cases, respectively. Adequate material was obtained in 242 cases. The cases were broadly classified into neoplastic and nonneoplastic categories. Malignancies and specific granulomatous diseases, tuberculosis and sarcoidosis were the main diseases diagnosed. Brushings showed a sensitivity of 88.2% and a specificity of 98.9% for the diagnosis of neoplasms. On the other hand, washings had only a 34.9% sensitivity and a 98.6% specificity in diagnosing neoplastic disorders. We concluded that FOB is a safe and effective tool in the diagnostic work-up of suspected malignancies and neoplastic lung diseases.