Renal replacement therapy in critically ill patients with acute kidney injury: 2020 nephrologist's perspective

Association between ACE (rs4343 and rs1799752), AGTR1 (rs5186), and PAI-1 (rs2227631) polymorphisms in the host and the severity of Covid-19 infection

OBJECTIVE

It is necessary to identify appropriate clinical, biochemical, epidemiological and genetic biomarkers to elucidate the underlying mechanisms of the coronavirus disease-2019 (COVID-19) disease. The study focused on not only the link between disease severity (non-intense unit care (non-ICU) versus intensive unit care (ICU) and genetic susceptibility in COVID-19 patients but also the connection between comorbidity and genetic susceptibility affecting the severity of COVID-19.

SUBJECT AND METHODS

One hundred and sixty-two COVID-19 patients treated in the non-ICU and ICU in Kayseri City Hospital were included. All volunteers underwent a physical examination and biochemical evaluation. Angiotensin-converting enzyme (ACE p.T776T G > A(rs4343) and g.16471_16472delinsALU (also referred to as I/D polymorphism; rs1799752), angiotensin II receptor type-1 (AGTR1) c.*86A > C (also referred to as A1166C; rs5186), and plasminogen activator inhibitor-1 (PAI-1-844 G > A (rs2227631) polymorphisms were analysed as well.

RESULTS

To have ACE "ID" genotype did not change the severity of the disease (OR: 0.92, 95% CI: 0.41-2.1, p = 0.84), but decreased the mortality risk 2.9-fold (OR: 2.9, 95% CI: 1.1-7.0, p = 0.03). In PAI-1-844 G > A, having the "AA" genotype in the "A" recessive model increased the risk of the diabetes mellitus (DM) 2.3-fold (OR: 2.3 95%, CI: 1.16-4.66, p = 0.018). In the "G" recessive model, to have the GG genotype increased the risk of chronic kidney disease (CKD) 4.8-fold (OR:4.8, 95% CI: 1.5-15.5, p = 0.008). "GG" genotype in the DM group had a higher fibrinogen level compared to those with the "AG" genotype (AG:4847.2 mg/L (1704.3) versus GG:6444.67 mg/L (1861.62) p = 0.019) and "AA" genotype in the CKD group had lower platelet levels and those with "GG" had higher platelet levels (AA:149 µL (18-159) versus GG: 228 µL (146-357) p = 0.022).

CONCLUSION

This study was shown that genetic predispositions that causes comorbidities were also likely to affect the prognosis of COVID-19.

Efficacy of Continuous Renal Replacement Therapy and Intermittent Hemodialysis in Patients with Renal Failure in Intensive Care Unit: A Systemic Review and Meta-analysis

Objective

This study aimed to compare the clinical efficacy of continuous renal replacement therapy (CRRT) and intermittent hemodialysis (IHD) in patients with renal failure in intensive care unit (ICU).

Methods

Relevant studies were searched in the databases including EMBASE, Cochrane Library, and MEDLINE (PubMed) from inception to January 04, 2021. The inclusion of available studies and the collection of data were independently conducted by two authors after reviewing the full text. Pooled analyses of relative risk (RR) and weighted mean difference (WMD) were performed to compare the outcomes of renal recovery, short-term mortality, length of ICU stays, and length of in-hospital stays between the two different treatment groups. Publication bias was assessed by the funnel plot.

Results

A total of 11 RCT studies including 1740 patients with renal failure were eligible for final analysis. Among them, 894 patients (51.4%) underwent CRRT and 846 patients (48.6%) received IHD. Pooled analysis did not find significant differences in renal recovery and short-term mortality between the two groups. Interestingly, patients underwent CRRT showed significantly shorter length of ICU stay and in-hospital stay than those who underwent IHD (ICU stay: RR: -0.61, 95%CI: -1.10--0.11, P < 0.05; I² = 93.6%; in-hospital stay: RR: -0.56, 95%CI: -1.41-0.28, P < 0.05; I² = 97.7%). No significant publication biases were observed on the funnel plots.

Conclusion

Compared with IHD, CRRT had similar effects on renal recovery and short-term mortality in patients with renal failure in ICU. As a promising technique in clinical practice, CRRT could significantly reduce the length of ICU stay and in-hospital stay of patients, which was of great significance for the reduction of medical costs and the long-term benefits of patients, thereby reducing the burden on society and individuals.

Clec7a expression in inflammatory macrophages orchestrates progression of acute kidney injury

Acute kidney injury (AKI) is associated with high risk of mortality, post-disease renal fibrosis, kidney dysfunction and renal failure. Renal macrophages play a key role in the pathogenesis (M1 subpopulation), healing and remodeling (M2 subpopulation) in AKI and, thus, have been a promising target for clinical treatment of AKI. Here, in a mouse renal ischemia/reperfusion injury (IRI) model for AKI, we showed that renal macrophages could be further classified into Clec7a+ M1 macrophages, Clec7a- M1 macrophages, Clec7a+ M2 macrophages and Clec7a- M2 macrophages, representing distinct macrophage populations with different functionality. Interestingly, Clec7a+ M1 macrophages exhibited potent pro-inflammatory and phagocytic effects compared to Clec7a- M1 macrophages, while Clec7a- M2 macrophages exhibited better proliferating and migrating potential, which is critical for their role in tissue repairing after injury. These data from mice were further strengthened by bioinformatics analyses using published database. In vivo, combined expression of Clec7a in M1 macrophages and depletion of Clec7a in M2 macrophages significantly improved the renal function after IRI-AKI. Together, our data suggest that Clec7a is crucial for the fine regulation of macrophage phenotype during AKI and could be a novel target for boosting clinical therapy.