title: Critically ill patients requiring acute renal replacement therapy are at an increased risk of long-term renal dysfunction, but rarely receive specialist nephrology follow-up.
abstract: BACKGROUND
  Episodes of acute kidney injury (AKI) have been associated with the development of chronic kidney disease (CKD). However, follow-up pathways for patients who have survived AKI complicating critical illness are not well established. We hypothesised that patients who had AKI requiring renal replacement therapy (RRT) in intensive care are at risk of CKD, but are rarely referred for nephrology follow-up at hospital discharge.
  
  
  METHODS
  We performed a retrospective analysis of all patients who survived AKI requiring renal replacement therapy in intensive care units (ICUs) in the East London region, examining renal function at baseline, hospital discharge and 3-6 months follow-up. We excluded patients who were known to renal services prior to index admission.
  
  
  RESULTS
  From 5,544 critical care admissions, we identified 219 patients who survived to be discharged, having undergone RRT for AKI, that were not previously known to renal services. Of these, 124 (57%) had creatinine measured within 3-6 months after discharge, 104 having a pre-morbid baseline for comparison. Only 26 patients (12%) received specialist nephrology follow-up. At 3-6 months follow-up, the estimated glomerular filtration rate was significantly lower than baseline (48 vs. 60 ml/min/1.73 m(2); p < 0.001), with the prevalence of CKD stage III-V rising from 49 to 70% (p < 0.001).
  
  
  CONCLUSIONS
  Follow-up of patients who required RRT for AKI in ICU is inconsistent despite evidence of a significant increase in the prevalence of CKD. There is strong justification for the development of robust pathways to identify survivors of AKI in order to detect and manage CKD and its complications.
authors.affiliation: Adult Critical Care Unit, The Royal London Hospital, Barts Health NHS Trust, London, UK.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Kirwan
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Blunden
authors.forename: Hamish
authors.initials: H
authors.lastname: Dobbie
authors.forename: Ajith
authors.initials: A
authors.lastname: James
authors.forename: Ambika
authors.initials: A
authors.lastname: Nedungadi
authors.forename: John R
authors.initials: JR
authors.lastname: Prowle
mesh_terms: D058186:Acute Kidney Injury / Q000150:complications* / Q000401:mortality / Q000628:therapy*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003266:Continuity of Patient Care; D003404:Creatinine / Q000097:blood; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D009398:Nephrology; D010820:Physicians; D051436:Renal Insufficiency, Chronic / Q000209:etiology* / Q000401:mortality / Q000517:prevention & control; D017582:Renal Replacement Therapy / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D003404:Creatinine