Sepsis is a life-threatening condition associated with high morbidity and mortality. The breakdown of proteins mainly from skeletal muscles leads to the release of free amino acids (FAAs). The serum FAA pool has been repeatedly assessed and found to be significantly altered in patients with sepsis/septic shock. Sepsis is well known to be the most common factor contributing to the development of acute kidney injury in critically ill patients.

The investigators want to establish the baseline profile of FAAs and their derivatives in patients with sepsis/septic shock undergoing continuous renal replacement therapy due to sepsis-associated acute kidney injury. Secondly, the investigators want to compare the FAA profiles of the survivors and nonsurvivors.

Inclusion Criteria:

• over 18 years of age
• present AKI
• requiring renal replacement therapy
• hospitalized at the ICU.

Exclusion Criteria:

• acute kidney disease requiring renal replacement therapy prior to admission to the ICU
• chronic kidney disease requiring renal replacement therapy prior to admission to the ICU
• history of past CRRT.

All patients hospitalized in ICU who met inclusion criteria.