Neutrophil defects and deficiencies

Neutrophilic granulocytes (neutrophils) are major players in the innate immune system, especially in the defense against bacteria and fungi. Neutrophils are the most abundant white blood cell (leukocyte) in the circulation and are typically the first leukocyte to be recruited to the site of infection or inflammation. In this thesis we have investigated both inborn and acquired neutrophil defects, which still cause considerable morbidity and mortality despite advances in medical care. We have tried to gain more insight in characteristics of one specific inborn neutrophil functional disorder, named p40phox deficient chronic granulomatous disease (CGD), as well as in the pathophysiology of the autoreactivity observed frequently in CGD. We have also investigated the functionality of and indications for granulocyte transfusions (GTX), used as a last resort treatment in patients with refractory infections and neutropenia or neutrophil dysfunction. Finally, we have conducted a clinical study in patients with severe neutropenia as a result of chemotherapy. We assessed the value of different laboratory biomarkers for early identification of patients with febrile neutropenia and a high risk for infection-related IC admission and death