Alfred Ankrah: Positron emission tomography in infections associated with immune dysfunction
This thesis explores the role of Positron Emission Tomography (PET) in infections associated with immune dysfunction. PET is a medical imaging technique that images biological processes in the body. Whole body PET provides 3-dimensional images which allows it to display infections from various regions and deep within the body cavity.
The thesis examined three infections: Human immunodeficiency virus (HIV), tuberculosis (TB) and invasive fungal infections (IFIs). All three infections require treatment over long periods of time and usually require monitoring of the efficacy of the treatment or the side effects of some drugs.
In HIV, PET can evaluate and follow-up infections and malignancies associated with HIV. The metabolic uptake in the lymph nodes reflects viral replication and allows staging of HIV.
In TB and IFIs, PET provides detection of early sites of infection and all sites of disease in the body in a single examination, and allows monitoring of treatment of these infections. Monitoring of infections is useful in complex IFIs and TB, where traditional methods of monitoring are often suboptimal.
PET was found to have a predictive value in both TB and IFIs, which can help clinicians consider different treatment options early in the course of infection.
PET imaging is done with different tracers which allow evaluation of different biochemical processes in the body. In the thesis, the advantages of imaging TB with different tracers and the potential role of imaging hypoxia in TB were explored.