METHODS: Ninety three patients with lower respiratory tract infections (LRTI) enrolled in the study and assigned into 3 groups; 66 patients in group 1, 13 in group 2, and 14 in group 3. Patients in group 1 were subjected to BAL with 50 ml saline, followed by the same volume of SB from the same lobe. In group 2, BAL was done with 10 ml of saline followed by 50 ml SB followed by 50 ml saline. In group 3, BAL was done with 50 ml saline then the retrieved sample was divided into two equal volumes; one diluted with equal volume of saline and the other diluted with equal volume of SB. All samples were subjected to pH measurement, Gram staining, aerobic bacterial culture, Ziehl-Neelsen (ZN) staining, TB culture, fungal wet mount stain and fungal culture.