ABSTRACT
Our study was designed to test the hypothesis that an early morning sputum may be sufficient for calculation of early bactericidal activity (EBA). Patients underwent sputum collection randomly (spot, 5â¯h and 12â¯h) in consecutive days. The median CFU count in the spot samples group was 5.67 log10 CFU/mL compared to 6.17 log10 CFU/mL in 5â¯h and 6.23 log10 CFU/mL in 12â¯h samples. Inter-patient comparison showed low coefficient of variation for both 12â¯h (11%) and 5â¯h samples (10%). Intrapatient samples analysis demonstrated that the median bacillary load variation (0.037 log10 CFU/mL and 0.022 log10 CFU/mL for 5 and 12â¯h samples respectively) was comparable to the other EBA studies and did not vary significantly from one day of collection to another. We concluded that 5â¯h pooled sputum when collected appropriately in the morning can be sufficient for calculation of EBA.