Hospital-Acquired Acute Kidney Injury in Non-Critical Medical Patients in a Developing Country Tertiary Hospital: Incidence and Predictors

Background

Acute kidney injury (AKI) is a frequent complication in critical patients, leading to a worse prognosis. Although its consequences are worse among critical patients, AKI is also associated with less favorable outcomes in non-critical patients. Therefore, understanding the magnitude of the problem in these patients is crucial, yet there is a scarcity of evidence in non-critical settings, especially in resource limited countries. Hence, the study aimed at determining the incidence and predictors of hospital acquired acute kidney injury (HAAKI) in non-critical medical patients who were admitted at a large tertiary hospital in Ethiopia.

Methods

A retrospective chart review study was conducted from September 25, 2022 to January 20, 2023 among 232 hospitalized non-critical medical patients admitted to St. Paul's Hospital Millennium Medical College between January 2020 and January 2022. The incidence of HAAKI was estimated using incidence density per total person day (PD) observation of the study participants. To identify predictors of HAAKI, a log binomial regression model was fitted at a p value of ≤0.05. The magnitude of association was measured using adjusted relative risk (ARR) with its 95% CI.

Results

During the median follow-up duration of 11 days (IQR, 6-19 days), the incidence of HAAKI was estimated to be 6.0 per 100 PD (95% CI = 5.5 to 7.2). Significant predictors of HAAKI were found to be having type 2 diabetes mellitus (ARR = 2.36, 95% CI = 1.03, 5.39, p-value=0.042), and taking vancomycin (ARR = 3.04, 95% CI = 1.38, 6.72, p-value=0.006) and proton pump inhibitors (ARR = 3.80, 95% CI = 1.34,10.82, p-value=0.012).

Conclusion

HAAKI is a common complication in hospitalized non-critical medical patients, and is associated with a common medical condition and commonly prescribed medications. Therefore, it is important to remain vigilant in the prevention and timely identification of these cases and to establish a system of rational prescribing habits.

Community-acquired versus hospital-acquired acute kidney injury at a large Australian metropolitan quaternary referral centre: incidence, associations and outcomes

BACKGROUND

There is increasing global incidence of acute kidney injury (AKI) and significant short- and long-term impacts on patients.

AIMS

To determine incidence and outcomes of community-acquired AKI (CA-AKI) and hospital-acquired AKI (HA-AKI) among inpatients in the Australian healthcare setting using modern health information systems.

METHODS

A retrospective cohort study of adult patients admitted to a quaternary hospital in Melbourne, Australia, between 1 January 2018 and 31 December 2019 utilising an electronic data warehouse. Participants included adult patients admitted for >24 h who had more than one serum creatinine level recorded during admission. Kidney transplant and maintenance dialysis patients were excluded. Main outcomes measured included AKI, as classified by the Kidney Disease Improving Global Outcomes (KDIGO) criteria, hospital length of stay and 30-day mortality.

RESULTS

A total of 6477 AKI episodes was identified across 43 791 admissions. Of all AKI episodes, 77% (n = 5011), 15% (n = 947) and 8% (n = 519) were KDIGO stage 1, 2 and 3 respectively. HA-AKI accounted for 55.9% episodes. Patients required intensive care unit admission in 22.7% (n = 1100) of CA-AKI and 19.3% (n = 935) of HA-AKI, compared with 7.5% (n = 2815) of patients with no AKI (P = 0.001). Patients with AKI were older with more co-morbidities, particularly chronic kidney disease (CKD). Length of stay was longer in CA-AKI (8.8 days) and HA-AKI (11.8 days) compared with admissions without AKI (4.9 days; P < 0.001). Thirty-day mortality was increased with CA-AKI (10.2%) and HA-AKI (12.8%) compared with no AKI (3.7%; P < 0.001).

CONCLUSION

The incidence of AKI detected by the electronic data warehouse was higher than previously reported. Patients who experienced AKI had greater morbidity and mortality. CKD was an important risk factor for AKI in hospitalised patients.

Subphenotypes of acute kidney injury in children

PURPOSE OF REVIEW

The purpose of this review is to describe acute kidney injury (AKI) phenotypes in children.

RECENT FINDINGS

AKI is a heterogenous disease that imposes significant morbidity and mortality on critically ill and noncritically ill patients across the age spectrum. As our understanding of AKI and its association with outcomes has improved, it is becoming increasingly apparent that there are distinct AKI subphenotypes that vary by cause or associated conditions. We have also learned that severity, duration, and repeated episodes of AKI impact outcomes, and that integration of novel urinary biomarkers of tubular injury can also reveal unique subphenotypes of AKI that may not be otherwise readily apparent.

SUMMARY

Studies that further delineate these unique AKI subphenotypes are needed to better understand the impact of AKI in children. Further delineation of these phenotypes has both prognostic and therapeutic implications.

Higher ambient nitrogen dioxide is associated with an elevated risk of hospital-acquired acute kidney injury

BACKGROUND

Previous studies have suggested that long-term exposure to air pollution increases the risk of chronic kidney disease and its progression. However, the effect of air pollution on the risk of acute kidney injury (AKI) has not been studied. We aim to evaluate the transient effect of air pollution on the risk of hospital-acquired AKI (HA-AKI).

METHODS

We selected from the Epidemiology of AKI in Chinese Hospitalized patients cohort AKI cases in which the onset date could be unambiguously determined. We obtained city-specific daily averages of the ambient level of particulate matter (2.5 μm and 10 μm), carbon monoxide, nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and ozone (O₃) from the Ministry of Environmental Protection of China. We used the time-stratified case-crossover approach to examine the association between the ambient level of air pollutants and the risk of HA-AKI in the selected cases.

RESULTS

A total of 11 293 AKI cases that met the inclusion and exclusion criteria were selected. In univariable analysis, the ambient levels of NO₂ and SO₂ were significantly associated with the risk of HA-AKI. In the multivariable analysis that incorporated all six pollutants in the same model, NO₂ was the sole pollutant whose level remained associated with the risk of AKI (P < 0.001). The relationship between the level of NO₂ and the risk of HA-AKI appeared to be linear, with an estimated odds ratio of 1.063 (95% confidence interval 1.026-1.101) for each increment of 1 median absolute deviation in the exposure. The association was consistent across the subgroups stratified by age, gender, baseline estimated glomerular filtration rate, AKI severity, need for intensive care and season.

CONCLUSIONS

Higher ambient levels of NO₂ are associated with an increased risk of HA-AKI in hospitalized adults in China.

Serum cystatin C: A potential predictor for hospital-acquired acute kidney injury in patients with acute exacerbation of COPD

Hospital-acquired acute kidney injury (HA-AKI) is associated with poor prognosis. In this study, we evaluated whether serum cystatin C on admission could predict AKI in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). The retrospective study was conducted using data on adult inpatients with AECOPD from January 2014 to January 2017. A total of 1035 patients were included, among which 79 (7.6%) with HA-AKI were identified. Univariate and multivariate logistic regression analyses were used to investigate predictors of HA-AKI in patients with AECOPD. HA-AKI was associated with poor prognosis, and patients with HA-AKI had higher inpatient mortality (34.2% vs. 2.6%, p < 0.001). Furthermore, after adjusting for confounders, HA-AKI was an independent risk factor for inpatient mortality for patients with AECOPD (odds ratio (OR) 11.02; 95% confidence interval (CI) 4.77–25.45; p < 0.001). Four independent risk factors for HA-AKI (age, levels of urea and cystatin C, and platelet count on admission) were identified in patients with AECOPD. Cystatin C (OR 5.22; 95% CI 2.49–10.95; p < 0.001) was a significant independent predictor of AKI in patients with AECOPD. HA-AKI in patients with AECOPD could be identified with a sensitivity of 73.5% and a specificity of 75.9% (area under the curve (AUC) = 0.803, 95% CI 0.747–0.859) by cystatin C level (cutoff value = 1.3 mg/L) and with a sensitivity of 75.9% and a specificity of 82.0% (AUC = 0.853, 95% CI 0.810–0.896) using a model comprising all significant predictors. Serum cystatin C has the potential for use to predict the risk of HA-AKI in patients with AECOPD.

Community-acquired versus hospital-acquired acute kidney injury in patients with acute exacerbation of COPD requiring hospitalization in China

Purpose

Previous studies have described the incidence, risk factors, and outcomes for patients with acute exacerbations of COPD (AECOPD) developing acute kidney injury (AKI). However, little is known about the differences between community-acquired AKI (CA-AKI) and hospital-acquired AKI (HA-AKI) in patients with AECOPD. Thus, in this study, we compared prevalence, risk factors, and outcomes for these patients with CA-AKI and HA-AKI.

Patients and methods

This study was conducted from January 2014 to January 2017, and data from adult inpatients with AECOPD were analyzed retrospectively. A total of 1,768 patients were included, 280 patients were identified with CA-AKI and 97 patients were with HA-AKI.

Results

Prevalence of CA-AKI was 15.8% and that of HA-AKI was 5.5%, giving an overall AKI prevalence of 21.3%. Patients with CA-AKI had a higher prevalence of chronic kidney disease (CKD) and lower prevalence of chronic cor pulmonale than patients with HA-AKI. Risk factors for developing HA-AKI and CA-AKI were similar, such as being elderly, requirement for mechanical ventilation, and a history of coronary artery disease and CKD. Patients with HA-AKI were more likely to have stage 3 AKI and worse short-term outcomes. In comparison with patients with CA-AKI, those with HA-AKI were more likely to require non-invasive mechanical ventilation (31.3% versus 16.8%; P = 0.003) and had a longer duration of mechanical ventilation (11 days versus 8 days; P = 0.020), longer hospitalization (14 days versus 12 days; P = 0.038), and higher inpatient mortality (32.0% versus 13.2%; P < 0.001). Patients with HA-AKI had worse (multivariate-adjusted) inpatient survival than those with CA-AKI (hazard ratio, 1.7 [95% confidence interval, 1.03-2.81; P = 0.038] for the HA-AKI group).

Conclusion

AKI was common in patients with AECOPD requiring hospitalization. CA-AKI was more common than HA-AKI but otherwise demonstrated similar demographics and risk factors. Nevertheless, patients with HA-AKI had worse short-term outcomes.

Epidemiology and Outcomes of Acute Kidney Injury in Critically Ill: Experience from a Tertiary Care Center

There is only limited information on the epidemiology and outcomes of acute kidney injury (AKI) in critically ill patients from low- and middle-income countries. This study aims to identify the etiology, short-term outcomes, and determinants of mortality in patients with AKI admitted to multiple medical and surgical Intensive Care Units (ICU's) in a tertiary care center. The study also aims to compare the clinical characteristics and outcomes of community-acquired AKI (CAAKI) and hospital-acquired AKI (HAAKI). A prospective, observational study was done from June 2013 to October 2015. All patients over 18 years with AKI admitted in various medical and surgical ICU's seeking nephrology referral were included. AKI was defined according to KDIGO criteria. The follow-up period was 30 days. A total of 236 patients were recruited from five medical and nine surgical ICU's. Majority (73.3%) were males. About 53.38% patients had CAAKI, whereas 46.61% had HAAKI. The predominant etiologies for AKI were sepsis (22.4%), trauma due to road traffic accidents (21.18%), acute abdomen (perforation, acute pancreatitis, bowel gangrene, intestinal obstruction and cholangitis) (18.64%), and cardiac diseases (10.59%). Sepsis and acute abdomen were the most common causes of CAAKI, whereas trauma and cardiac causes were the predominant causes of HAAKI (P < 0.05). Patients with HAAKI were younger, admitted in surgical units, had lower SOFA scores, lower serum creatinine, lesser need for dialysis, longer hospital stay, and earlier stages of AKI compared to patients with CAAKI (P < 0.05). The 30-day mortality was 52.54%. The mortality was not different between CAAKI and HAAKI (56.3% vs. 48.18%; relative risk = 0.86: 95% confidence interval 0.67–1.1). The mortality was similar across different stages of AKI.

Spectrum of acute kidney injury in the Himalayan region

Acute kidney injury (AKI) is common in hospitalized patients and is an important cause of mortality. This is a descriptive study of AKI in patients from Himachal Pradesh, India, located in Western Himalayan region. Over a period of 1 year, 102 patients with clinical and laboratory evidence of azotemia were included. Out of 102 patients, 84.3% had community acquired AKI and 15.7% had hospital acquired AKI. Medical causes were leading contributors (85.3%), with septicemia being the main factor (33.3%). Multiorgan failure was present in 59.8% patients. The overall mortality was 29.2%, and community acquired AKI was associated with higher mortality as compared to hospital-acquired AKI (22.5% vs 6.7%). AKI is still common in community and associated with high mortality. Septicemia, volume depletion and nephrotoxins were the leading cause of AKI in our study. Our study highlights the presence of hypotension, multiorgan failure and oliguria with mortality. Community-acquired AKI had higher mortality than hospital-acquired AKI.