Here, we measured presepsins (PSPs) in four patients with acute kidney injury (AKI) or chronic kidney disease (CKD) and discuss the relationship between PSP and kidney dysfunction. Case 1: an 83-year-old man was admitted to the ICU to manage postoperative respiratory failure with AKI. He had undergone resection for rectal cancer and ileal conduit replacement. On day 1 in the ICU, Escherichia coli (E. coli) was isolated by urine culture. PSP level (pg/ml) on day 2 was 2,745 without elevation of other conventional biomarkers. On day 6, the patient was diagnosed with severe sepsis, and E. coli was isolated by blood culture. By then, PSP had risen to 3,977, along with elevation of other conventional biomarkers. His kidney function recovered gradually after continuous administration of hemodiafiltration; however, PSP continued to rise up to 6,051, along with high systemic inflammatory response syndrome (SIRS) and Acute Physiology and Chronic Health Evaluation (APACHE) II values. The patient expired on day 13 due to multiple organ failure. Case 2: a 78-year-old woman with CKD on hemodialysis (HD) was admitted to the ICU after cardiovascular surgery. Continuous HD was administered postoperatively, and PSP ranged from 1,473-1,870 without signs of sepsis. Temporary elevation of other conventional biomarkers was observed postoperatively. Case 3: a 74-year-old woman with CKD on HD was admitted to the ICU after neurosurgery. She underwent intermittent HD postoperatively, and PSP ranged from 1,240-1,935 without sepsis symptoms. Temporary elevation of other conventional biomarkers was observed postoperatively. Case 4: a 62-year-old man with CKD was admitted to the ICU to control gastrointestinal bleeding. PSP was 606 without signs of infection or elevation of other conventional biomarkers. In cases 2, 3, and 4, bacteria were not isolated in blood cultures. Patients' clinical prognoses were good, with low or moderate SIRS and APACHE II scores. PSP in kidney dysfunction patients will be high despite non-infectious conditions. Therefore, evaluation of PSP in kidney dysfunction patients will be difficult. Further investigation is needed to clarify the relationship between PSP and kidney dysfunction.
Keywords: Acute kidney injury; Chronic kidney disease; Presepsin; Sepsis.