Role of bronchoalveolar lavage in diagnosing pulmonary infections and malignancies: Experience from a tertiary care center.

Abstract

Bronchoalveolar lavage (BAL), is a safe, minimally invasive procedure to sample the terminal airways and the lung parenchyma. Although frequently used, there is lack of contemporary literature regarding the diagnostic utility of BAL for various pulmonary diseases. This study was conducted to evaluate the utility of BAL in diagnosis of various pulmonary pathologies, both infectious and neoplastic. This was a retrospective study performed over a period of 2 years. All the BAL samples reported on cytology were studied, their clinical details were retrieved, and the corresponding smears were reviewed. Cyto-histopathologic correlation was done, wherever possible. There were a total of 1835 cases (1153 men, 682 women; age, 8 months to 78 years). Of these, 19 (1%) cases were assessed as inadequate for opinion. In 348 (19%) cases, specific infective cause could be identified on BAL cytology alone. Tuberculosis and fungal infections could be diagnosed in 165 (9%) and 178 (9.7%) cases respectively. There were 46 (2.5%) neoplasms, including adenocarcinoma (n = 20), squamous cell carcinoma (n = 5), small cell carcinoma (n = 2), Langerhans cell histiocytosis (n = 1), suspicious for malignancy (n = 15) and metastatic carcinoma (n = 3). Some rare diagnoses were also reported on BAL cytology, including sarcoidosis, actinomycosis, leishmaniasis, pulmonary alveolar proteinosis and metastatic papillary carcinoma of the thyroid. BAL is a safe and useful procedure for primary diagnosis of infections such as tuberculosis and fungal infections, which has special significance in developing nations where prevalence of such infections is high. In addition, BAL has the potential to diagnose both primary as well as secondary malignant lung lesions.