Temporal Relationship and Clinical Outcomes of Acute Kidney Injury Following Acute Respiratory Distress Syndrome: A Systematic Review and Meta-Analysis

OBJECTIVES

Conduct a systematic review and meta-analysis to assess prevalence and timing of acute kidney injury (AKI) development after acute respiratory distress syndrome (ARDS) and its association with mortality.

DATA SOURCES

Ovid MEDLINE(R), Ovid Embase, Ovid Cochrane Central Register of Controlled Trials, Ovid Cochrane Database of Systematic Reviews, Ovid PsycINFO database, Scopus, and Web of Science thought April 2023.

STUDY SELECTION

Titles and abstracts were screened independently and in duplicate to identify eligible studies. Randomized controlled trials and prospective or retrospective cohort studies reporting the development of AKI following ARDS were included.

DATA EXTRACTION

Two reviewers independently extracted data using a pre piloted abstraction form. We used Review Manager 5.4 software (Cochrane Library, Oxford, United Kingdom) and Open Meta software (Brown University, Providence, RI) for statistical analyses.

DATA SYNTHESIS

Among the 3646 studies identified and screened, 17 studies comprising 9359 ARDS patients met the eligibility criteria and were included in the meta-analysis. AKI developed in 3287 patients (40%) after the diagnosis of ARDS. The incidence of AKI at least 48 hours after ARDS diagnosis was 20% (95% CI, 0.18-0.21%). The pooled risk ratio (RR) for the hospital (or 30-d) mortality among ARDS patients who developed AKI was 1.93 (95% CI, 1.71-2.18). AKI development after ARDS was identified as an independent risk factor for mortality in ARDS patients, with a pooled odds ratio from multivariable analysis of 3.69 (95% CI, 2.24-6.09). Furthermore, two studies comparing mortality between patients with late vs. early AKI initiation after ARDS revealed higher mortality in late AKI patients with RR of 1.46 (95% CI, 1.19-1.8). However, the certainty of evidence for most outcomes was low to very low.

CONCLUSIONS

While our findings highlight a significant association between ARDS and subsequent development of AKI, the low to very low certainty of evidence underscores the need for cautious interpretation. This systematic review identified a significant knowledge gap, necessitating further research to establish a more definitive understanding of this relationship and its clinical implications.

Acetazolamide for acute kidney injury in patients undergoing high dose methotrexate therapy: a systematic review and meta-analysis

BACKGROUND

Urine alkalization is one of the standard treatments to prevent acute kidney injury in patients receiving high-dose methotrexate. Carbonic anhydrase inhibitors are promising adjuvants/substitutes with advantages such as faster urine alkalization time and prevention of fluid overload. However, there is limited and contradictory evidence on its efficacy and safety. We aimed to compare the efficacy and safety of carbonic anhydrase inhibitors to standard treatments in adult patients receiving high-dose methotrexate.

METHODS

The protocol was registered at PROSPERO (CRD42022352802) in August 2021. We evaluated the use of carbonic anhydrase inhibitors in combination with standard treatment compared to standard treatment alone. We excluded articles irrelevant to the efficacy and safety of acetazolamide in patients receiving high dose methotrexate and/or did not provide sufficient data regarding doses, recruitment criteria, and follow-up period. Two authors performed the data extraction independently.

RESULTS

Among 198 articles retrieved, six observational studies met all eligibility criteria. Four studies with five datasets (totaling 558 patients/cycles) had enough data to be included in the meta-analysis. We independently report the results from the two remaining studies. The results did not show a significant difference between acetazolamide versus standard treatment in acute kidney injury (AKI) rate (OR = 0.79, 95% CI 0.48-1.29, P = 0.34, I2 = 0%). Regarding the time to urine pH goal, there was no significant time difference between the two groups (Mean Difference = 0.07, 95% CI - 1.9 to 2.04, P = 0.95, I2 = 25%). Furthermore, our meta-analysis showed that acetazolamide did not reduce length of stay (Mean Difference = 0.75, 95% CI - 0.8 to 2.31, P = 0.34, I2 = 0%). In one study, the only reported side effect of acetazolamide was hypokalemia (nearly 50% in the acetazolamide group).

CONCLUSIONS

This systematic review showed no significant difference between acetazolamide and standard care treatment regarding urine alkalinization time and AKI rate in adult patients receiving high dose methotrexate. We suggest performing a large blinded, randomized, controlled trial to evaluate the potential benefits of this low-cost medication.

Systematic Review of Cardiovascular Benefits and Safety of Sacubitril-Valsartan in End-Stage Kidney Disease

Introduction

Patients with end-stage kidney disease (ESKD) frequently develop heart failure, contributing to high mortality. Limited data exist on cardiovascular benefits and safety of sacubitril-valsartan in this population. Our systematic review aims to evaluate the efficacy and safety of sacubitril-valsartan versus standard care in patients with ESKD who are on dialysis.

Methods

We conducted a search in Embase, MEDLINE, and Cochrane databases to identify relevant studies and assessed outcomes using random-effect model and generic inverse variance approach.

Results

Analysis of 12 studies involving 799 eligible patients with ESKD revealed improvement in left ventricular ejection fraction (LVEF) with sacubitril-valsartan compared to a control group with pooled mean difference (MD) 6.58% (95% confidence interval [CI]: 1.86, 11.29). LVEF significantly improved in patients with LVEF <50% (heart failure with reduced ejection fraction [HFrEF] and heart failure with moderately reduced ejection fraction [HFmrEF]) with MD 12.42% (95% CI: 9.39, 15.45). However, patients with LVEF >50% (heart failure with preserved ejection fraction [HFpEF]) did not exhibit statistically significant effect, MD 2.6% (95% CI: 1.15, 6.35). Sacubitril-valsartan significantly enhanced LVEF in patients with HFrEF, with MD 13.8% (95% CI: 12.04, 15.82). Safety analysis indicated no differences in incidence of hyperkalemia (pooled odds ratio [OR] 0.72; 95% CI: 0.38, 1.36) or hypotension (pooled risk ratio [RR] 1.03; 95% CI: 0.36, 2.98). No cases of angioedema were reported. However, safety analysis relies on evidence of limited robustness due to the observational nature of the studies.

Conclusion

Our systematic review suggests that sacubitril-valsartan benefits patients with ESKD with HFrEF and HFmrEF by improving LVEF without increasing the risk of hyperkalemia, hypotension, or angioedema compared to standard care. However, safety analysis based on observational studies inherently has limitations for establishing causal relationships.

Development and Implementation of an Acute Kidney Injury Remote Patient Monitoring Program: Research Letter

Acute kidney injury (AKI) survivors have a dynamic posthospital course which warrants close monitoring. Remote patient monitoring (RPM) could be used to improve quality and efficiency of AKI survivor care.

Objective

The objective of this report was to describe the development and preliminary feasibility of an AKI RPM program launched in October 2021.

Setting

Academic medical center.

Patients

Patients enrolled in the AKI RPM program were those who experienced AKI during a hospitalization and underwent nephrology consultation.

Measurements/Methods

At enrollment, patients were provided with home monitoring technology and underwent weekly laboratory assessments. Nurses evaluated the data daily and adhered to prespecified protocols for management and escalation of care if needed.

Results

Twenty patients were enrolled in AKI RPM in the first 5 months. Median duration of program participation was 36 (31, 40) days. Eight patients (40%) experienced an unplanned readmission, or an emergency department visit, half (N = 4) of which were attributed to AKI and related circumstances. Of the 9 postgraduation survey respondents, all were satisfied with the RPM program and 89% would recommend RPM to other patients with similar health conditions.

Limitations

Acute kidney injury RPM was made possible by the existing infrastructure in our integrated health system and the robust resources available in the Mayo Clinic Center for Digital Health. Such infrastructure may not be universally available which could limit scale and generalizability of such a program.

Conclusions

Remote patient monitoring can offer a unique opportunity to bridge the care transition from hospital to home and increase access to quality care for the AKI survivors.

Effects of Mediterranean Diet, DASH Diet, and Plant-Based Diet on Outcomes among End Stage Kidney Disease Patients: A Systematic Review and Meta-Analysis

BACKGROUND

The Mediterranean, Dietary Approach to Stop Hypertension (DASH), and plant-based diets may provide cardiovascular benefit to the general population. However, data on their effect on end stage kidney disease (ESKD) patients are limited. This systematic review aims to assess the impact of Mediterranean, DASH, and plant-based diets on outcomes among ESKD patients.

METHODS

A literature review was conducted in EMBASE, MEDLINE, and Cochrane databases from inception through September 2022 to identify studies that assess the clinical outcomes of Mediterranean, DASH, or plant-based diets on ESKD patients on hemodialysis (HD) or peritoneal dialysis (PD). Effect estimates from the individual studies were derived utilizing the random-effect, generic inverse variance approach of DerSimonian and Laird.

RESULTS

Seven studies with 9400 ESKD patients (8395 HD and 1005 PD) met the eligibility criteria and were included in the data analysis. Pooled odds ratios (ORs) of mortality for ESKD patients who adhered to the Mediterranean versus plant-based diet were 0.49 (95% CI: 0.07-3.54; two studies, I² = 67%) and 0.87 (95% CI: 0.75-1.01; two studies, I² = 0%), respectively. Data on mortality for ESKD patients on a DASH diet were limited to one study with an OR of 1.00 (95% CI: 0.89-1.12). The pooled OR of cardiovascular mortality among ESKD patients who adhered to a plant-based diet was 0.86 (95% CI: 0.68-1.08; two studies, I² = 0%), compared to those who did not. Data on cardiovascular mortality among those with Mediterranean and DASH diet were limited to one study with ORs of 1.14 (95% CI: 0.90-1.43) and 1.19 (95% CI: 0.99-1.43), respectively. Mediterranean diet adherence was found to be associated with reduced risk of left ventricular hypertrophy (LVH) with an OR of 0.82 (95% CI: 0.68-0.99) in a study including 127 ESKD patients. The risk of hyperkalemia was not significant among those with a plant-based diet with an OR of 1.00 (95% CI: 0.94-1.07) in a study including 150 ESKD patients.

CONCLUSIONS

While our systematic review demonstrated no significant associations of Mediterranean, DASH, and plant-based diets with reduced all-cause mortality or cardiovascular mortality, there was also no evidence that suggested harmful effects of these diets to ESKD patients.

A Case of Adrenal Insufficiency Diagnosed Using Optimal Dosing of Cosyntropin During Stimulation Testing

Patient: Female, 45-year-old

Final Diagnosis: Asthma

Symptoms: Chills • diaphoresis • emesis • nausea • shortness of breath

Medication: —

Clinical Procedure: —

Specialty: Endocrinology and Metabolic

Type 2 diabetes is associated with increased risk of critical respiratory illness in patients COVID-19 in a community hospital

Background

Type 2 diabetes (T2D) is the leading non-communicable disease worldwide and is associated with several microvascular and macrovascular complications. Individuals with T2D are more prone to acquiring selected types of infections and are more susceptible to complications due to these infections. This study aimed to evaluate the relationship between T2D and COVID-19 in the community setting.

Methods

This was a single-center retrospective analysis that included 147 adult patients with laboratory-confirmed COVID-19 admitted to a community hospital. Demographics, medical history, symptoms and signs, laboratory findings, complications during the hospital course, and treatments were collected and analyzed. The Kaplan-Meier method was used to describe the probability of intubation in patients with T2D as compared with patients without T2D. The hazard ratio for intubation in the survival analysis was estimated using a bivariable Cox proportional-hazards model.

Results

Of 147 patients, 73 (49.7%) had a history of T2D. Patients with T2D had higher requirement of ICU admission (31.5% vs 12.2%; p = .004), higher incidence of ARDS (35.6% vs 16.2%, p = .007), higher rates of intubation (32.9% vs 12.2%, p = .003), and higher use neuromuscular blocking agents (23.3% vs 9.5%, p = .02). In the survival analysis at 28 days of follow-up, patients with T2D showed an increased hazard for intubation (HR 3.00; 95% CI, 1.39 to 6.46).

Conclusion

In our patient population, patients with COVID-19 and T2D showed significantly higher ARDS incidence and intubation rates. The survival analysis also showed that after 28 days of follow-up, patients with T2D presented an increased risk for shorter time to intubation.

Effects of fibrinogen synthesis inhibition on vascular cognitive impairment during traumatic brain injury in mice

Traumatic brain injury (TBI) is associated with increased blood content of fibrinogen (Fg), called hyperfibrinogenemia (HFg), which results in enhanced cerebrovascular permeability and leads to short-term memory (STM) reduction. Previously, we showed that extravasated Fg was deposited in the vasculo-astrocyte interface and was co-localized with cellular prion protein (PrP^C) during mild-to-moderate TBI in mice. These effects were accompanied by neurodegeneration and STM reduction. However, there was no evidence presented that the described effects were the direct result of the HFg during TBI. We now present data indicating that inhibition of Fg synthesis can ameliorate TBI-induced cerebrovascular permeability and STM reduction. Cortical contusion injury (CCI) was induced in C57BL/6J mice. Then mice were treated with either Fg antisense oligonucleotide (Fg-ASO) or with control-ASO for two weeks. Cerebrovascular permeability to fluorescently labeled bovine serum albumin was assessed in cortical venules following evaluation of STM with memory assessement tests. Separately, brain samples were collected in order to define the expression of PrP^C via Western blotting while deposition and co-localization of Fg and PrP^C, as well as gene expression of inflammatory marker activating transcription factor 3 (ATF3), were characterized with real-time PCR. Results showed that inhibition of Fg synthesis with Fg-ASO reduced overexpression of AFT3, ameliorated enhanced cerebrovascular permeability, decreased expression of PrP^C and Fg deposition, decreased formation of Fg-PrP^C complexes in brain, and improved STM. These data provide direct evidence that a CCI-induced inflammation-mediated HFg could be a triggering mechanism involved in vascular cognitive impairment seen previously in our studies during mild-to-moderate TBI.

Fibrinogen-cellular prion protein complex formation on astrocytes

Traumatic brain injury (TBI) is one of the most common neurological disorders causing memory reduction, particularly short-term memory (STM). We showed that, during TBI-induced inflammation, increased blood content of fibrinogen (Fg) enhanced vascular protein transcytosis and deposition of extravasated Fg in vasculo-astrocyte interfaces. In addition, we found that deposition of cellular prion protein (PrP^C) was also increased in the vasculo-astrocyte endfeet interface. However, association of Fg and PrP^C was not confirmed. Presently, we aimed to define whether Fg can associate with PrP^C on astrocytes and cause their activation. Cultured mouse brain astrocytes were treated with medium alone (control), Fg (2 mg/mL or 4 mg/mL), 4 mg/mL of Fg in the presence of a function-blocking anti-PrP^C peptide or anti-mouse IgG, function-blocking anti-PrP^C peptide, or anti-mouse IgG alone. After treatment, either cell lysates were collected and analyzed via Western blot or coimmunoprecipitation was performed, or astrocytes were fixed and their activation was assessed with immunohistochemistry. Results showed that Fg dose-dependently activated astrocytes, increased expressions of PrP^C and tyrosine (tropomyosin) receptor kinase B (TrkB), and PrP gene. Blocking the function of PrP^C reduced these effects. Coimmunoprecipitation demonstrated Fg and PrP^C association. Since it is known that prion protein has a greater effect on memory reduction than amyloid beta, and that activation of TrkB is involved in neurodegeneration, our findings confirming the possible formation of Fg-PrP^C and Fg-induced overexpression of TrkB on astrocytes suggest a possible triggering mechanism for STM reduction that was seen previously during mild-to-moderate TBI.NEW & NOTEWORTHY For the first time we showed that fibrinogen (Fg) can associate with cellular prion protein (PrP^C) on the surface of cultured mouse brain astrocytes. At high levels, Fg causes upregulation of astrocyte PrP^C and astrocyte activation accompanied with overexpression of tyrosine receptor kinase B (TrkB), which results in nitric oxide (NO) production and generation of reactive oxygen species (ROS). Fg/PrP^C interaction can be a triggering mechanism for TrkB-NO-ROS axis activation and the resultant astrocyte-mediated neurodegeneration.

SUN-LB8 Cross Sex Hormone Therapy and Breast Cancer in Transgender Male to Female

Case Presentation: We are presenting a 53-year-old Male to Female transgender patient who has been receiving estradiol valerate injections every 14 days for 13 years and had no gender surgical reassignment procedures or breast implants. Her past medical history was significant for HIV on Highly Active Anti-retroviral therapy (HAART). No family history of breast cancer. She presented with severe bilateral left elbow, lower back and bilateral chest pain for 3 days. Chest CT done to exclude pulmonary embolism showed an incidental 4 cm right breast mass. Enlarged lymph nodes in the right axilla, scattered lytic lesions in the axial skeleton and the left humeral head were also noted. Breast exam was not performed until the significant findings were seen in CT chest and it showed a palpable hard-circumscribed subareolar right breast mass without skin changes. Ultrasound guided biopsy of the breast mass confirmed invasive ductal carcinoma of the breast. The patient had no previous mammogram testing. Oncology work-up was positive for estrogen and progesterone receptors but negative for human epidermal growth factor-2 receptor. The patient opted to return home in another state to seek treatment and further oncological workup but subsequently lost follow up. Discussion: Male to female breast cancer was first recognized in 1968. However, risk factors for this condition remain unclear. In our patient, long-term use of Cross-sex Hormone Therapy (CHT) represented a major risk factor for breast cancer. In a Dutch study, the risk of breast cancer increased during a relatively short duration of CHT and the cancer characteristics reassembled female pattern. As theoretically implicated, increased estrogen exposure in males may have a role in the proliferation of neoplastic breast epithelium. There are growing evidence to support increasing rates of breast cancer in HIV-positive population, making it a potential risk factor as well. Loss of CXCR-4 protective effect promoted by HIV virus may explain the increase in the breast cancer incidence after the introduction of HAART. In general, routine screening for breast cancer in MTF transgender population remains controversial. The Endocrine Society Clinical Practice guidelines suggest that MTF transsexual individuals who have no known increased risk of breast cancer should follow screening guidelines for biological women. While the Canadian Cancer Society recommends screening mammography every two years for MTF individuals taking CHT for more than 5 years and those between the ages of 50 and 69 years.

Conclusion:Breast cancer in MTF transgender patients is associated with receiving CHT and represents diagnostic and treatment challenge. More research is need to comment on routine breast cancer screening in this population. However, physicians should remember performing a regular breast exam in MTF individuals looking for a possible mass.

Vascular and non-vascular contributors to memory reduction during traumatic brain injury

Traumatic brain injury (TBI) is an increasing health problem. It is a complex, progressive disease that consists of many factors affecting memory. Studies have shown that increased blood-brain barrier (BBB) permeability initiates pathological changes in neuro-vascular network but the role of cerebrovascular dysfunction and its mediated mechanisms associated with memory reduction during TBI are still not well understood. Changes in BBB, inflammation, extravasation of blood plasma components, activation of neuroglia lead to neurodegeneration. Extravasated proteins such as amyloid-beta, fibrinogen, and cellular prion protein may form degradation resistant complexes that can lead to neuronal dysfunction and degeneration. They also have the ability to activate astrocytes, and thus, can be involved in memory impairment. Understanding the triggering mechanisms and the places they originate in vasculature or in extravascular tissue may help to identify potential therapeutic targets to ameliorate memory reduction during TBI. The goal of this review is to discuss conceptual mechanisms that lead to short-term memory reduction during non-severe TBI considering distinction between vascular and non-vascular effects on neurons. Some aspects of these mechanisms need to be confirmed further. Therefore, we hope that the discussion presented bellow may lead to experiments that may clarify the triggering mechanisms of memory reduction after head trauma.

Hyperfibrinogenemia-mediated astrocyte activation

Fibrinogen (Fg)-containing plaques are associated with memory loss during various inflammatory neurodegenerative diseases such as Alzheimer's disease, multiple sclerosis, stroke, and traumatic brain injury. However, mechanisms of its action in neurovascular unit are not clear. As Fg is a high molecular weight blood protein and cannot translocate far from the vessel after extravasation, we hypothesized that it may interact with astrocytes first causing their activation. Cultured mouse cortical astrocytes were treated with Fg in the presence or absence of function-blocking anti-mouse intercellular adhesion molecule 1 (ICAM-1) antibody, or with medium alone (control). Expressions of ICAM-1 and tyrosine receptor kinase B (TrkB) as markers of astrocyte activation, and phosphorylation of TrkB (pTrkB) were assessed. Fg dose-dependently increased activation of astrocytes defined by their shape change, retraction of processes, and enhanced expressions of ICAM-1 and TrkB, and increased pTrkB. Blocking of ICAM-1 function ameliorated these Fg effects. Data suggest that Fg interacts with astrocytes causing overexpression of ICAM-1 and TrkB, and TrkB phosphorylation, and thus, astrocyte activation. Since TrkB is known to be involved in neurodegeneration, interaction of Fg with astrocytes and the resultant activation of TrkB can be a possible mechanism involved in memory reduction, which were observed in previous studies and were associated with formation of complexes of Fg deposited in extravascular space with proteins such as Amyloid beta or prion, the proteins involved in development of dementia.