DiscussionToxoplasmosis in the immunocompromised host can have serious consequences and, if not recognised, a fatal outcome. The number of patients undergoing haemopoietic stem cell transplant has increased dramatically in the last few years in the UK. This procedure greatly suppresses the patient's immune system making them vulnerable to infections, such as toxoplasmosis. This talk presents the clinical presentations, predisposing risks and diagnosis of this disease in these patients. Prophylaxis and treatment are also discussed.