Gene Expression Profiles in Spinal Tuberculosis.

Tuberculosis (TB) is one of the top ten causes of death worldwide with approximately 10 million cases globally and 1.2 million deaths. Sub-Saharan Africa carries the highest burden of TB. South Africa has one of the highest HIV and TB rates worldwide with an HIV prevalence rate in adults of 19% and a TB case notification rate of 615/100,000 in 2019. Over many years, focus has been paid to pulmonary TB and extrapulmonary TB (EPTB) has received only little attention even though it accounts for almost a quatre of all TB cases. The diagnosis of EPTB remains challenging simply because sample collection requires invasive procedures in the absence of a blood-based diagnostic test. Spinal TB (spondylitis or spondylodiscitis caused by Mycobacterium tuberculosis) - often known as Pott's disease - accounts for up to 10% of EPTB and affects young children, people with HIV-coinfection and elderly, and often leads to lifelong debilitating disease due to devastating deformation of the spine and compression of neural structures. Little is known with regards to the extent of disease and isolated TB spine as well as a disseminated form of TB spine have been described. The latter presents with a spinal manifestation plus disseminations to other organs such as the lungs, pleura, lymph nodes, the GIT or urinary tract or even the brain. In the Spinal TB X cohort, the investigators aim to describe the clinical phenotype of spinal TB using whole body PET/CT and identify a specific gene expression profile for the different stages of dissemination and compare findings to previously described signatures for latent and active pulmonary TB. A blood-based test for spinal TB would lead to earlier diagnosis and treatment in all settings globally and improve treatment outcome of this devastating disease.