Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Molecular bacterial load assay (MBLA) rapidly quantifies viable Mycobacterium tuberculosis (Mtb) and may be useful for monitoring treatment response and treatment efficacy. We conducted a prospective study in 56 adults with pulmonary tuberculosis from whom 244 sputum samples were collected before and during the first month of treatment. We evaluated MBLA for early monitoring of bacterial burden and investigated bactericidal activities of first-line therapy in patients infected with drug susceptible and resistant isolates. Mtb loads measured by MBLA and culture were correlated after one-week (r = 0.56) and one-month (r = 0.73) of treatment. Correlations between culture and GeneXpert or microscopy were weaker during treatment. Mtb load by MBLA declined more rapidly than GeneXpert after one-week (2.73 Ct, P < 0.001; 0.95 Ct, P = 0.297, respectively) and one-month (8.94 Ct, P < 0.001; 6.78 Ct, P < 0.001). Mtb loads in multidrug resistant (MDR) infections were significantly greater than in both sensitive and poly/mono-resistance after one-week (P < 0.02) and one-month treatment (P = 0.001). MBLA performed better than GeneXpert and microscopy in comparison to culture for quantifying viable Mtb during treatment. It can be used for monitoring bacterial load during TB treatment, facilitating early detection of treatment failure thus improving outcomes.

Original publication





Tuberculosis (Edinburgh, Scotland)

Publication Date





Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam.