Acute Kidney Injury Masked by Malnutrition: A Case Report and the Problem of Protein

Abstract

Acute kidney injury (AKI) is common among critically ill patients. There are a number of nutrition considerations in the management of AKI, including fluid balance, electrolyte and acid‐base disturbances, protein provision, and management of comorbid conditions. The optimal amount of protein provision for patients with AKI who are not on renal replacement therapy (RRT) has been a topic of debate for years. Excessive protein provision may contribute to azotemia in these patients, but inadequate protein intake may harm nutrition status and result in poorer clinical outcomes. This review discusses a patient case of AKI masked by malnutrition and muscle loss and reviews the current literature on optimal protein intake in AKI (not on RRT). Based on a structured search strategy, 4 articles were reviewed. We conclude that the available evidence suggests that significant restrictions in protein intake are not necessary for those critically ill patients with AKI. However, the studies reviewed here showed significant heterogeneity in protein dose and delivery, estimation of protein needs, patient population, and definition of AKI, and thus further research is needed to systematically determine the optimal dose of protein for critically ill adults with AKI.

The Effects of Malnutrition on Inpatient Outcomes in Patients With Gastroparesis: A Nationwide Analysis

“…While previous studies have shown that malnutrition is associated with an increased risk of developing AKI, the analysis of this population did not reveal an associated increased risk of AKI [40]. This could be due to the under-recognition of AKI in malnourished patients [41]. Serum creatinine is reflective of somatic protein stores, and these levels may be decreased in patients with malnourishment due to decreased muscle mass.…”

Protein delivery in intermittent and continuous enteral nutrition with a protein-rich formula in critically ill patients—a protocol for the prospective randomized controlled proof-of-concept Protein Bolus Nutrition (Pro BoNo) study

“…Clinically significant acute or chronic kidney failure with GFR < 20 ml/min. Schwartz et al [ 34 ] concluded that although significant restrictions in protein intake may not be necessary for critically ill patients with acute kidney injury, excessive protein provision in these patients could have a negative effect on renal function and lead to azotaemia. For safety reasons, the GFR value is intentionally set low to exclude patients with severely restricted kidney function.…”

Protein delivery in intermittent and continuous enteral nutrition with a protein-rich formula in critically ill patients - A protocol for the prospective randomised controlled proof-of-concept Protein Bolus Nutrition (Pro BoNo) study

“…Schwartz et al (32) concluded that although significant restrictions in protein intake may not be necessary for critically ill patients with acute kidney injury, excessive protein provision in these patients could have a negative effect on renal function and lead to azotaemia. For safety reasons, the GFR value is intentionally set low to exclude patients with severely restricted kidney function.…”