Renal perfusion and neutrophil-mediated inflammation will be assessed in the kidney in sepsis patients with acute kidney injury using positron emission tomography. For marked water will be used for renal perfusion and a newly developed PET tracer molecule (11C-GW457427) with specific binding to neutrophil elastase which provides a measure of the amount of infiltrating neutrophils in the renal parenchyma for inflammation. The study is performed in a PET-CT camera where anatomical imaging takes place at the same time as the PET examinations.

To study renal perfusion and neutrophil-mediated inflammation 10 critically ill patients with sepsis and acute kidney injury (AKI) and 5 healthy volunteers as controls will be recruited and examined at one time with marked water followed by neutrophil elastase tracer. At the same time, a CT scan is performed for anatomy. Plasma levels of inflammatory mediators will be measured. Clinical data will be collected. The endpoints are changes in renal perfusion and increased presence of neutrophil elastase in the renal parenchyma.

Inclusion Criteria:

Patients with sepsis and AKI

• > 30 years
• At least AKI stage 1 according to KDIGO where the last plasma creatinine is measured within 24 hours of the examination

Healthy volunteers

• > 30 years
• No previously known kidney disease
• Normal plasma creatinine value

Exclusion Criteria:

• Chronic renal failure (CKD stage >3a) or dialysis
• Instability in vital functions that makes PET-CT examination unsuitable
• Claustrophobia or other reasons that make the patient unable to lie still during the examination.
• Pregnancy and breastfeeding

Critically ill patients with sepsis and AKI and healthy volunteers

The underlying data for this study will not be made publicly available. However, the data may be acquired from the authors upon reasonable request after permission from the Swedish ethical review authority and under the limitations of the general data protection act of the European Union.