Tuberculosis is a bacterial infection causing 1.1 million deaths annually worldwide.
Diagnosis of the disease is often time consuming or challenging. Many cases of tuberculosis
require advanced and expensive diagnostic methods that restrict their availability in
resource limited countries where the burden of tuberculosis is highest. The development of
rapid point of care diagnostics is required.
Lipoarabinomannan (LAM) is part of the bacterial cell wall in M. tuberculosis. It is released
when bacteria are multiplying or dying. LAM can be detected in the urine since it is filtered
from the blood in the kidneys. The detection of LAM in the urine by conventional enzyme
linked immuno-sorbent assay (ELISA) techniques was hampered in the past by a low sensitivity
and multiple processing steps. Recently, fluorescence linked immuno-sorbent assay (FLISA) has
been shown to detect LAM in concentrations that are several magnitudes lower that with ELISA
based methods. Furthermore the procedure requires less separate steps for processing the
This study aims to validate the new diagnostic test by comparing patients with (a) confirmed
tuberculosis (n=25), (b) infection with non-tuberculous mycobacteria (n=25), (c) bronchial
carcinoma (n=25), (d) suspected tuberculosis but confirmed alternative diagnosis (estimated
n=20). Single blood and urine samples of these groups will be used to evaluate the
sensitivity and specificity of the test.
In patients with confirmed tuberculosis the LAM FLISA will also be assessed as a biomarker
for the monitoring of tuberculosis treatment success. Initially, 2-5 samples blood and urine
are required during the first week, followed by twice weekly and weekly sampling intervals
over a period of 12 weeks maximum. The study participation ends when the patient is
discharged from hospital.
As a substudy, the blood samples will be used to evaluate an enzyme linked immuno-sorbent
assay (ELISA) for the detection of lipid antigens that are specific for Mycobacterium