Proenkephalin A and Kidney Replacement Therapy

Study Overview
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Brief Summary
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Acute kidney injury (AKI) is a common problem encountered in the intensive care unit (ICU), estimated to occur in up to 60% of all critically ill patients, depending on the definition. Recent large randomized clinical trials in critical care nephrology have focused on the optimal timing of initiation of acute kidney replacement therapy (KRT). However, less is known about the ideal circumstances in which KRT may be successfully discontinued. The novel serum-biomarker proenkephalin A 119-159 (penkid) has been found to be strongly negatively correlated with measured GFR. Whether penkid may have a role in initiation and discontinuation of KRT remains unknown.

Detailed Description
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Acute kidney injury (AKI) is a common problem encountered in the intensive care unit (ICU), estimated to occur in up to 60% of all critically ill patients, depending on the definition. Recent large randomized clinical trials in critical care nephrology have focused on the optimal timing of initiation of acute kidney replacement therapy (KRT). However, less is known about the ideal circumstances in which KRT may be successfully discontinued. KRT is a complex and expensive therapy, with complications including catheter-associated infections, hemorrhage, hemodynamic instability, and potential delayed renal recovery. The novel serum-biomarker proenkephalin A 119-159 (penkid) is a stable fragment derived from the precursor enkephalins, which are known as small endogenous opioid peptides and are produced throughout the human body, including the kidneys. Plasma concentrations of penkid have been found to be strongly negatively correlated with measured glomerular filtration rate. Whether penkid may have a role in initiation and discontinuation of KRT remains unknown.

Official Title
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Proenkephalin A at Initiation and Discontinuation of Kidney Replacement Therapy

Conditions
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Acute Kidney Injury

Intervention / Treatment
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* Other: None planned


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients ≥18 years of age with AKI requiring KRT Exclusion Criteria: Chronic kidney disease with estimated glomerular filtration rate <30 mL/min/1.73 m2 Non-end stage renal disease with extracorporeal ultrafiltration due to diuretic- resistant fluid overload Decision to limit therapeutic interventions History of solid-organ transplants Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| AKI necessitating KRT<br>Patients with AKI necessitating KRT | Other: None planned<br>* No intervention planned<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Penkid levels at KRT initiation | Serial assessment of penkid in patients undergoing KRT | Up to 2 weeks | 
| Penkid levels at discontinuation of KRT | Serial assessment of penkid in patients undergoing KRT | Up to 2 weeks |