O4
ACUTE KIDNEY INJURY IN UROLOGY PATIENTS: INCIDENCE, CAUSES AND
OUTCOMES
Caddeo G1, Williams S1, McIntyre C2, Selby N2
1
Department of Urology, Royal Derby Hospital, Derby, 2Department of Renal Medicine,
Royal Derby Hospital, Derby
INTRODUCTION:
Acute kidney injury (AKI) is common in hospitalised patients and is associated with high mortality
rates. However, the epidemiology of AKI in urology patients may differ due to a higher proportion
of post-renal causes and surgical procedures that result in the intentional removal of renal
parenchyma. We performed a study to examine the incidence, aetiology and outcomes of AKI in a
urological population.
METHODS:
Patients who sustain AKI at our centre are identified by a hospital-wide, electronic AKI reporting
system, based on the Acute Kidney Injury Network (AKIN) criteria. This system populates a
prospective database, from which all patients who sustained AKI and had urology as their primary
speciality were retrieved for a 17 month period. Additional data on aetiology of AKI and surgical
procedures performed were obtained retrospectively by manual searching of paper and electronic
medical records.
RESULTS:
Between October 2010 and February 2012 there were 587 episodes of AKI in 410 urology patients
(6.7% of all hospitalised urology patients within the same time period). 273 patients (66.6%) were
non-elective admissions, whilst 137 cases (33.4%) sustained AKI during the course of an elective
admission. In the elective group, 58 patients (42.3%) underwent nephrectomy (radical and partial)
or nephroureterectomy; other procedures that were complicated by AKI included
TURBT/cystodiathermy of bladder tumour (21 patients, 15.3%) and radical cystectomy (10
patients, 5.8%). For emergency admissions, obstructive causes and urinary sepsis accounted for the
majority of cases.
Overall 30-day mortality was lower than reports in other patient groups at 7.8% (32 pts). The
severity of AKI retained an association with mortality (4.8% in stage 1, 9.1% in stage 2 and 14.9%
in stage 3, chi square for trend p<0.05). Of those that did not survive, 22 (68.7%) were associated
with urological malignancy.
At the time of discharge, only 237 (57.7%) patients had achieved complete recovery of renal
function.
CONCLUSION:
AKI is common in urology patients but is associated with a lower mortality than other patient
populations. This likely reflects the underlying aetiologies of AKI in this group, although it is
important to note that the severity of AKI retains an association with mortality. However, the low
rate of renal recovery suggests that urology patients who sustain AKI are exposed to a significant
risk of chronic kidney disease and its attendant consequences for long term health.