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Nephrotoxin Microinjection in Zebrafish to Model Acute Kidney Injury
Published on: July 17, 2016
Adverse outcomes associated with both diagnosed and undiagnosed acute kidney injury
Zena Barakat1, Timothy J Pianta2,3
1Department of Medicine, Northern Health, Epping, Victoria, Australia.
Insights
Acute kidney injury (AKI) is frequently under-diagnosed and under-coded in hospitals. Improved diagnosis and follow-up are crucial, as adverse outcomes occur whether AKI is documented or not.
Area of Science:
- Nephrology
- Hospital Medicine
- Health Informatics
Background:
- Acute kidney injury (AKI) is a common complication in hospitalized patients.
- Diagnosis and documentation of AKI are inconsistent, leading to under-recognition.
- Administrative coding underestimates AKI prevalence compared to biochemical markers.
Purpose of the Study:
- Identify factors influencing AKI diagnosis, documentation, and coding.
- Examine outcomes for AKI survivors, including those with undiagnosed AKI.
Main Methods:
- Retrospective cohort study of inpatients (July 2016).
- AKI diagnosis and staging based on KDIGO 2012 criteria.
- Outcomes (readmission, mortality) assessed up to 12 months post-discharge.
Main Results:
- 22% of patients had AKI; only 29% had it noted in discharge summaries.
- Accurate AKI documentation correlated with CKD and severe AKI stages.
- AKI patients had higher readmission and mortality rates, irrespective of documentation status.
Conclusions:
- Significant under-recognition and under-coding of AKI in hospitals.
- Adverse outcomes persist regardless of AKI documentation, emphasizing need for better care.
- Limited nephrologist involvement and follow-up for AKI patients.
Background:
Acute kidney injury (AKI) is common among hospitalised patients, yet its diagnosis and documentation are inconsistent. Administrative codes show limited sensitivity for diagnosing AKI compared to biochemical criteria. Thus, AKI is often missed or poorly communicated, and the impact of under-recognised AKI is inadequately understood.
Aims:
This study aimed to identify factors influencing the diagnosis, documentation and coding of AKI and examine outcomes among survivors, including those with undiagnosed AKI.
Methods:
This was a single-centre retrospective cohort study, reviewing medical records and funding codes for inpatients admitted between 1 July and 28 July 2016. AKI diagnosis and staging were determined using the KDIGO 2012 criteria. Outcomes, including readmissions and mortality rates, were examined up to 12 months after admission.
Results:
Of the 1194 patients who participated, 263 (22.0%) experienced AKI. Among those with AKI, 50.6% had documentation, 39.9% had coding for administrative funding and only 29.0% had the diagnosis noted in the discharge summary. Accurate documentation of AKI was associated with pre-existing chronic kidney disease (odds ratio (OR): 15.8, 95% CI: 6.0-41.9, P < 0.001) and Stage 2 (OR 3.0, 95% CI: 1.2-7.3, P = 0.017) or Stage 3 AKI (OR 22.9, 95% CI: 2.9-181, P = 0.03). Readmission or death after discharge was higher in patients with AKI than in those without (hazard ratio (HR): 2.2, P < 0.001 and HR: 4.7, P < 0.001 respectively). However, risks were similar in those with documented versus undocumented AKI (HR: 1.2, P = 0.20 and HR: 1.2, P = 0.58 respectively). Only 9.1% (95% CI: 5.9%-13%) of inpatients with AKI received nephrologist care, and 5.3% were referred for outpatient nephrology follow-up.
Conclusions:
This study highlights the under-recognition and under-coding of AKI. Importantly, adverse outcomes were observed regardless of whether AKI was documented, underscoring the need for improved diagnosis, communication and follow-up.
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