Low-Flow Acute Kidney Injury: The Pathophysiology of Prerenal Azotemia, Abdominal Compartment Syndrome, and Obstructive Uropathy

The STING antagonist SN-011 ameliorates cisplatin induced acute kidney injury via suppression of STING/NF-κB-mediated inflammation

Acute kidney injury (AKI) is a critical clinical syndrome associated with both innate and adaptive immune responses and thus increases mortality. Nevertheless, specific therapeutics for AKI are scarce so far. Recent studies have revealed that knockout of STING alleviate AKI, suggesting that STING could be an attractive target for AKI therapy. SN-011, a promising STING inhibitor, has not been reported in studies of its anti-AKI activity. In this study, we sought to examine the effects of SN-011 on AKI and explore its underlying mechanism. Our findings indicate that SN-011 could modulate the NF-κB and MAPK pathways, suppress the expression of inflammatory factors, and decrease ROS release in the cisplatin-induced cell model. In addition, SN-011 blocked the nuclear translocation of NF-κB p65, further mitigating the inflammatory response. In vivo, SN-011 enhanced survival rates and alleviated renal dysfunction. According to gene set enrichment analysis of sequencing data from mouse kidneys, we further confirm that SN-011 modulates the NF-κB and MAPK pathways. Our study suggests that SN-011 could be an attractive anti-inflammatory agent for further anti-AKI research.

The Metabolism of Creatinine and Its Usefulness to Evaluate Kidney Function and Body Composition in Clinical Practice

Serum creatinine levels are the most used clinical marker to estimate renal function as the glomerular function rate because it is simple, fast, and inexpensive. However, creatinine has limitations, as its levels can be influenced by factors such as advanced age, physical activity, protein-rich diets, male gender, medications, and ethnicity. Serum cystatin C and its combination with serum creatinine may serve as an alternative since these factors do not affect it. Most creatinine synthesis occurs in the muscles, making it a valuable marker for assessing lean body mass within body composition. This measurement is crucial for evaluating and monitoring nutritional status in patients with chronic kidney disease. This review aimed to discuss the literature on creatinine metabolism, its advantages and disadvantages in assessing renal function, and its utility in measuring lean body mass. The variability in the creatinine generation rate among individuals should be considered when assessing the glomerular function rate.

Copper Intoxication in South American Camelids-Review of the Literature and First Report of a Case in a Vicuña (Vicugna vicugna)

Copper (Cu), an essential trace element in the metabolism of mammals, plays a central role in various metabolic processes. However, overdosing can lead to severe symptoms and even fatalities. Chronic Cu intoxication continues to be a problem in grazing and domestic animals, with sheep being particularly sensitive. There are few comparative studies on its impact on South American camelids (SACs). Therefore, this work presents the results of literature research combined with a case report on a 3-year-old female vicuña (Vicugna vicugna) presented to the clinic from a zoological garden in northern Germany. The animal showed reduced food intake, recumbency, bruxism, icteric mucous membranes and sclera. Auscultation revealed atony of the third compartment and the digestive tract. Similar to cases described in the literature, the animal showed rapid deterioration of its condition with unspecific symptoms of liver failure and rapid death. However, in contrast to descriptions in sheep, clinical icterus has not been previously reported in cases of other SACs. Laboratory findings from EDTA and serum samples revealed neutrophilia with a left shift, hypoproteinaemia, lymphopaenia, azotaemia, elevated levels of creatine kinase (CK), aspartate aminotransferase (AST) and glutamate dehydrogenase (GLDH) in the serum. Hyperbilirubinaemia and significantly elevated serum and liver Cu levels were observed. Subsequent blood samples from the remaining vicuñas and alpacas in the same enclosure showed no remarkable abnormalities. To the best of the authors' knowledge, this case report represents the first documented case of Cu intoxication specifically in vicuñas.

A case of frequent of prerenal acute kidney injury attacks: importance of recognizing systemic capillary leak syndrome: a case report

Systemic capillary leak syndrome (SCLS) is a rare and life-threatening disorder. A man in his 60s presented for emergency care because of fatigue, decreased urine output and difficulty in moving his body. On admission, he was conscious, afebrile and had relative hypotension. Blood tests and urinary analysis revealed the following: white blood cell count, 19 500/μl; haematocrit, 64.5%; creatinine, 2.16 mg/dl; albumin, 3.3 g/dl; and 0.2% for fractional excretion of sodium. The patient was diagnosed with prerenal acute kidney injury (AKI) and was treated with intravenous fluid administration of more than 2 l/day. His kidney function gradually recovered after 4 days and creatinine decreased (1.15 mg/dl). However, he developed two more attacks of prerenal AKI during hospitalization, one of which needed intensive care unit management. Specific findings of hypotension, haemoconcentration, and hypoalbuminaemia were observed during all AKI attacks. Finally, he was diagnosed as idiopathic SCLS and was treated with intravenous immunoglobulin. SCLS might remain undiagnosed because of its rarity, but it can rapidly progress and lead to severe complications in absence of treatment. Clinicians need to consider this disease as a differential diagnosis when encountering patients who present with frequent prerenal AKI attacks accompanied by hypotension, haemoconcentration and hypoalbuminaemia.

Intestinal Ligation Mimicking Ureteral Ligation After Ovariohysterectomy in an 11-Month-Old Chihuahua

Intestinal ligation during ovariohysterectomy has not been previously reported in dogs. Risk factors for this complication appear to be the same as those for ureteral injury, namely decreased surgical visualization due to small patient size and small incision size. This case report describes how the presentation of intestinal ligation in a 2-kg, 11-month-old chihuahua can mimic that of iatrogenic ureteral injury with vomiting, anorexia, and severe azotemia. Ultrasound served as a key diagnostic to visualize intestinal mechanical obstruction, an encircling ligature around a segment of jejunum with no blood flow on Doppler interrogation, and normal appearance and blood flow of the ureters and kidneys. The treatment consisted of aggressive fluid therapy, circulatory support, and emergent resection and anastomosis of the necrotic portion of the intestines. Within 48 h, the dog's azotemia was resolved, and it was reported to be doing well at 1-month follow-up.

Clinical Utility of LC-MS/MS for Blood Myo-Inositol in Patients with Acute Kidney Injury and Chronic Kidney Disease

BACKGROUND

Diagnosing acute kidney injury (AKI) and chronic kidney disease (CKD) relies on creatinine, which lacks optimal diagnostic sensitivity. The kidney-specific proximal tubular enzyme myo-inositol oxygenase (MIOX) catalyzes the conversion of myo-inositol (MI) to D-glucuronic acid. We hypothesized that proximal tubular damage, which occurs in AKI and CKD, will decrease MIOX activity, causing MI accumulation. To explore this, we developed an LC-MS/MS assay to quantify plasma MI and assessed its potential in identifying AKI and CKD patients.

METHODS

MI was quantified in plasma from 3 patient cohorts [normal kidney function (n = 105), CKD (n = 94), and AKI (n = 54)]. The correlations between MI and creatinine were determined using Deming regression and Pearson correlation and the impact of age, sex, and ethnicity on MI concentrations was assessed. Receiver operating characteristic curve analysis was employed to evaluate MI diagnostic performance.

RESULTS

In volunteers with normal kidney function, the central 95th percentile range of plasma MI concentrations was 16.6 to 44.2 µM. Age, ethnicity, and sex showed minimal influence on MI. Patients with AKI and CKD exhibited higher median MI concentrations [71.1 (25th percentile: 38.2, 75th percentile: 115.4) and 102.4 (77, 139.5) µM], respectively. MI exhibited excellent sensitivity (98.9%) and specificity (100%) for diagnosing CKD. In patients with AKI, MI increased 32.9 (SD 16.8) h before creatinine.

CONCLUSIONS

This study unveils MI as a potential renal biomarker, notably elevated in plasma during AKI and CKD. Plasma MI rises 33 h prior to serum creatinine, enabling early AKI detection. Further validation and exploration of MI quantitation in kidney disease diagnosis is warranted.

Utility of fractional excretion of urea in acute kidney injury with comparison to fractional excretion of sodium: A systematic review and meta-analysis

BACKGROUND

Differentiating between intrinsic and prerenal acute kidney injury (AKI) presents a challenge. Here, we assessed the performance of the fractional excretion of urea (FEUrea) and compared it to the fractional excretion of sodium (FENa) in distinguishing intrinsic from prerenal AKI.

METHODS

A thorough search was conducted in several databases until January 16, 2024. We included studies evaluating FEUrea, with or without FENa, for differentiating AKI etiologies in adults. We assessed the methodological quality using the QUADAS-2 and QUADAS-C tools. We performed a meta-analysis using the bivariate random effects model, with subgroup analyses to explore the impact of diuretic therapy on FEUrea, and direct statistical comparisons between FEUrea and FENa involving the subgroups with and without diuretics.

RESULTS

We included 11 studies with 1108 hospitalized patients. Among eight studies (915 patients) evaluating FEUrea >35% for distinguishing intrinsic from prerenal AKI, the pooled sensitivity and specificity were 66% (95% CI, 49%-79%) and 75% (95% CI, 60%-85%), respectively. In a subset of six studies (302 patients) comparing FEUrea at 35% to FENa at 1% in patients not receiving diuretics, there were no significant differences in sensitivity (77% versus 89%, P = 0.410) or specificity (80% versus 79%, P = 0.956). In four studies, 244 patients on diuretics, FEUrea demonstrated lower sensitivity (52% versus 92%, P < 0.001) but higher specificity (82% versus 44%, P < 0.001) compared to FENa for the diagnosis of intrinsic AKI.

CONCLUSIONS

FEUrea has limited utility in differentiating intrinsic from prerenal AKI. FEUrea does not provide a superior alternative to FENa, even in patients receiving diuretics.

Understanding fluid dynamics and renal perfusion in acute kidney injury management

Acute kidney injury (AKI) is associated with an increased risk of morbidity, mortality, and healthcare expenditure, posing a major challenge in clinical practice, and affecting about 50% of patients in the intensive care unit (ICU), particularly the elderly and those with pre-existing chronic comorbidities. In health, intra-renal blood flow is maintained and auto-regulated within a wide range of renal perfusion pressures (60-100 mmHg), mediated predominantly through changes in pre-glomerular vascular tone of the afferent arteriole in response to changes of the intratubular NaCl concentration, i.e. tubuloglomerular feedback. Several neurohormonal processes contribute to regulation of the renal microcirculation, including the sympathetic nervous system, vasodilators such as nitric oxide and prostaglandin E2, and vasoconstrictors such as endothelin, angiotensin II and adenosine. The most common risk factors for AKI include volume depletion, haemodynamic instability, inflammation, nephrotoxic exposure and mitochondrial dysfunction. Fluid management is an essential component of AKI prevention and management. While traditional approaches emphasize fluid resuscitation to ensure renal perfusion, recent evidence urges caution against excessive fluid administration, given AKI patients' susceptibility to volume overload. This review examines the main characteristics of AKI in ICU patients and provides guidance on fluid management, use of biomarkers, and pharmacological strategies.

Blood transfusion reactions and risk of acute kidney injury and major adverse kidney events

BACKGROUND

Blood transfusion reactions may have a negative impact on organ function. It is unknown whether this association holds true for acute kidney injury (AKI). Therefore, we conducted a cohort study to assess the association between transfusion reactions and the incidence of AKI and major adverse kidney events.

METHODS

In this retrospective cohort study, we included patients who received transfusion of blood products during hospitalization at the Hospital Civil of Guadalajara. We analyzed them according to the development of transfusion reactions, and the aim was to assess the association between transfusion reactions and AKI during long-term follow-up.

RESULTS

From 2017 to 2021, 81,635 patients received a blood product transfusion, and 516 were included in our study. The most common transfusion was red blood cell packaging (50.4%), fresh frozen plasma (28.7%) and platelets (20.9%); of the 516 patients, 129 (25%) had transfusion reactions. Patients who had transfusion reactions were older and had more comorbidities. The most common type of transfusion reaction was allergic reaction (70.5%), followed by febrile nonhemolytic reaction (11.6%) and anaphylactoid reaction (8.5%). Most cases were considered mild. Acute kidney injury was more prevalent among those who had transfusion reactions (14.7%) than among those who did not (7.8%), p =  < 0.01; those with AKI had a higher frequency of diabetes, vasopressors, and insulin use. Transfusion reactions were independently associated with the development of AKI (RR 2.1, p =  < 0.02). Major adverse kidney events were more common in those with transfusion reactions. The mortality rate was similar between subgroups.

CONCLUSION

In our retrospective cohort of patients who received blood product transfusions, 25% experienced transfusion reactions, and this event was associated with a twofold increase in the probability of developing AKI and some of the major adverse kidney events during long follow-up.

Pre-existing chronic kidney disease, aetiology of acute kidney injury and infection do not affect renal outcome and mortality

BACKGROUND

We aimed to study the role of aetiology, pre-existing chronic kidney disease (CKD) and infections in acute kidney injury (AKI) on renal outcome and mortality.

METHODS

This retrospective study analysed patients with AKI admitted to a university nephrology department from January 1st, 2020 through December 31st, 2020. Aetiology of AKI, underlying renal disease in case of pre-existing CKD and presence of infections were assessed. Development of renal function and risk of death were studied with follow-up until January 31st, 2023.

RESULTS

Of 1402 patients screened, 432 patients (30.8%, 67.9 ± 15.4 years) fulfilled the inclusion criteria, half of the population presented with advanced CKD. Even though CKD patients were more often in need of chronic dialysis at time of discharge (6.9% vs 4.5%, p < .001), duration of hospital stay was shorter and in-hospital mortality tended to be lower when compared to AKI without prior renal disease. Neither aetiology of AKI nor pre-existing CKD had an impact on the combined endpoint of end-stage kidney disease and mortality (log rank 0.433 and 0.909). Overall, septic patients showed the highest in-hospital mortality (23.5%) and longest hospital stay (30.0 ± 22.8 days, p < .001), while patients with urosepsis had the shortest hospitalisation time (9.7 days) with lowest risk for dialysis (4.4%). Of note, outcome did not differ in patients with AKI when considering the infectious status.

CONCLUSIONS

Overall renal outcome and mortality in AKI patients were not affected by the cause of AKI, pre-existent CKD or infectious status. Only severity of AKI had a negative impact on outcome.

Point-of-Care Ultrasound for the Diagnosis of Congestive Kidney Due to Severe Acidemia: A Case Report

A 51-year-old woman with mitochondrial myopathy and congestive heart failure with reduced left ventricular ejection fraction was admitted due to loss of appetite and progressive frailty. She presented with acute kidney injury (AKI) and severe acidemia. Given her medical history and physical examination (jugular vein distention was not obvious), prerenal causes (hypovolemia/hypotension) of AKI were considered most likely. However, with a significantly elevated N-terminal pro-b-type natriuretic peptide level of 14,700 pg/mL, a congestive kidney was also considered. Bedside echocardiography showed no evidence of low output syndrome, whereas venous excess ultrasound (VExUS) score was assessed as Grade 2 (moderate congestion). In addition to administering fluids for the suspected prerenal causes (hypovolemia/hypotension), sodium bicarbonate was administered suspecting a negative impact of severe acidemia on cardiac function. With the improvement of acidemia and only a small volume of fluid therapy, there was a rapid improvement in AKI with the normalization of the VExUS score. This suggested that the main cause of AKI was congestive kidney. In this case, VExUS helped us make a correct diagnosis of acidemia-induced congestive kidney rather than hypovolemia as a cause of AKI, leading to the appropriate treatment.

Rac1 promotes kidney collecting duct repair by mechanically coupling cell morphology to mitotic entry

Prolonged obstruction of the ureter, which leads to injury of the kidney collecting ducts, results in permanent structural damage, while early reversal allows for repair. Cell structure is defined by the actin cytoskeleton, which is dynamically organized by small Rho guanosine triphosphatases (GTPases). In this study, we identified the Rho GTPase, Rac1, as a driver of postobstructive kidney collecting duct repair. After the relief of ureteric obstruction, Rac1 promoted actin cytoskeletal reconstitution, which was required to maintain normal mitotic morphology allowing for successful cell division. Mechanistically, Rac1 restricted excessive actomyosin activity that stabilized the negative mitotic entry kinase Wee1. This mechanism ensured mechanical G2-M checkpoint stability and prevented premature mitotic entry. The repair defects following injury could be rescued by direct myosin inhibition. Thus, Rac1-dependent control of the actin cytoskeleton integrates with the cell cycle to mediate kidney tubular repair by preventing dysmorphic cells from entering cell division.

Meta-analysis of perioperative outcomes and safety of percutaneous nephrostomy versus retrograde ureteral stenting in the treatment of acute obstructive upper urinary tract infection

Background

The debate regarding the optimal drainage method for acute obstructive upper urinary tract infection persists, focusing on the choice between percutaneous nephrostomy (PCN) and retrograde ureteral stenting (RUS).

Aims

This study aims to systematically examine the perioperative outcomes and safety associated with PCN and RUS in treating acute obstructive upper urinary tract infections.

Methods

A comprehensive investigation was conducted using the Medline, Embase, Web of Science, and Cochrane databases up to December 2022, following the guidelines of the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. The utilized keywords included 'PCN', 'RUS', 'acute upper obstructive uropathy', and 'RCT'. Inclusion criteria encompassed studies providing accurate and analyzable data, which incorporated the total subject count, perioperative outcomes, and complication rates. The assessed perioperative outcomes included fluoroscopy time, normalization of temperature, normalization of serum creatinine, normalization of white blood cell (WBC) count, and operative time. Safety outcomes encompassed failure rate, intraoperative and postoperative hematuria, postoperative fever, postoperative pain, and postoperative nephrostomy tube or stent slippage rate. The study protocol was prospectively registered at PROSPERO (CRD42022352474).

Results

The meta-analysis encompassed 7 trials involving 727 patients, with 412 assigned to the PCN group and 315 to the RUS group. The outcome of the meta-analysis unveiled a reduced occurrence of postoperative hematuria in the PCN group [odds ratio (OR) = 0.54, 95% confidence interval (CI) 0.30-0.99, p = 0.04], along with a decreased frequency of insertion failure (OR = 0.42, 95% CI 0.21-0.81, p = 0.01). In addition, the RUS group exhibited a shorter fluoroscopy time than the PCN group (mean difference = 0.31, 95% CI 0.14-0.48, p = 0.0004).

Conclusion

Given the significant impact of hematuria and catheterization failure on postoperative quality of life, the preference for PCN appears more advantageous than RUS.

Acute Kidney Injury: Definition, Management, and Promising Therapeutic Target

Acute kidney injury (AKI) is caused by a sudden loss of renal function, resulting in the build-up of waste products and a significant increase in mortality and morbidity. It is commonly diagnosed in critically ill patients, with its occurrence estimated at up to 50% in patients hospitalized in the intensive critical unit. Despite ongoing efforts, the death rate associated with AKI has remained high over the past half-century. Thus, it is critical to investigate novel therapy options for preventing the epidemic. Many studies have found that inflammation and Toll-like receptor-4 (TLR-4) activation have a significant role in the pathogenesis of AKI. Noteworthy, challenges in the search for efficient pharmacological therapy for AKI have arisen due to the multifaceted origin and complexity of the clinical history of people with the disease. This article focuses on kidney injury's epidemiology, risk factors, and pathophysiological processes. Specifically, it focuses on the role of TLRs especially type 4 in disease development.

Severe Acute Pancreatitis Treated with Negative Pressure Wound Therapy System: Influence of Laboratory Markers

(1) Background: An open abdomen is a serious medical condition that requires prompt and effective treatment to prevent complications and improve patient outcomes. Negative pressure therapy (NPT) has emerged as a viable therapeutic option for temporary closure of the abdomen, offering several benefits over traditional methods. (2) Methods: We included 15 patients with pancreatitis who were hospitalized in the I-II Surgery Clinic of the Emergency County Hospital "St. Spiridon" from Iasi, Romania, between 2011-2018 and received NPT. (3) Results: Preoperatively, the mean IAP level was 28.62 mmHg, decreasing significantly postoperatively to 21.31 mmHg. The mean level of the highest IAP value recorded in pancreatitis patients treated with VAC did not differ significantly by lethality (30.31 vs. 28.50; p = 0.810). In vacuum-treated pancreatitis patients with a IAP level > 12, the probability of survival dropped below 50% during the first 7 days of stay in the ICU, so that after 20 days the probability of survival was approximately 20%. IAP enters the determinism of surgery with a sensitivity of 92.3% and a specificity of 99%, the cut-off value of IAP being 15 mmHg. (4) Conclusions: The timing of surgical decompression in abdominal compartment syndrome is very important. Consequently, it is vital to identify a parameter, easy to measure, within the reach of any clinician, so that the indication for surgical intervention can be made judiciously and without delay.

Rapidly Blocking the Calcium Overload/ROS Production Feedback Loop to Alleviate Acute Kidney Injury via Microenvironment-Responsive BAPTA-AM/BAC Co-Delivery Nanosystem

Calcium overload and ROS overproduction, two major triggers of acute kidney injury (AKI), are self-amplifying and mutually reinforcing, forming a complicated cascading feedback loop that induces kidney cell "suicide" and ultimately renal failure. There are currently no clinically effective drugs for the treatment of AKI, excluding adjuvant therapy. In this study, a porous silicon-based nanocarrier rich in disulfide bond skeleton (<50 nm) is developed that enables efficient co-loading of the hydrophilic drug borane amino complex and the hydrophobic drug BAPTA-AM, with its outer layer sealed by the renal tubule-targeting peptide PEG-LTH. Once targeted to the kidney injured site, the nanocarrier structure collapses in the high glutathione environment of the early stage of AKI, releasing the drugs. Under the action of the slightly acidic inflammatory environment and intracellular esterase, the released drugs produce hydrogen and BAPTA, which can rapidly eliminate the excess ROS and overloaded Ca²⁺ , blocking endoplasmic reticulum/mitochondrial apoptosis pathway (ATF4-CHOP-Bax axis, Casp-12-Casp-3 axis, Cyt-C-Casp-3 axis) and inflammatory pathway (TNF-α-NF-κB axis) from the source, thus rescuing the renal cells in the "critical survival" state and further restoring the kidney function. Overall, this nanoparticle shows substantial clinical promise as a potential therapeutic strategy for I/R injury-related diseases.

Elevated soluble urokinase plasminogen activator receptor is associated with renal dysfunction in a Chlorocebus atheiops COVID-19 model

Increases of soluble urokinase plasminogen activator receptor (suPAR) were measured in both urine and plasma of a Chlorocebus aethiops (African green monkey; AGM) mucosal infected with SARS-CoV-2. The data indicate that elevated suPAR may be associated with renal dysfunction and pathology in the context of COVID-19.

Ogilvie Syndrome and Acute Kidney Injury: A Rare Complication of Cesarean Section and Preeclampsia

Ogilvie syndrome, or acute colonic pseudo-obstruction (ACPS) is a rare occurrence, usually following surgery. It consists of a massive dilatation of the cecum, whose diameter becomes greater than 10 cm; its severity is variable, but, if not promptly recognized, it may be life-threatening. Acute kidney injury (AKI) is reported in this context due to both septic complications and to effective hypovolemia. ACPS most commonly affects males and individuals older than 60. In women, the median age at diagnosis is lower due to a strong association with Caesarean sections. The differential diagnosis after delivery may be challenging, due to a potential overlap of symptoms with preeclampsia or hemolysis low platelet elevated liver enzymes (HELLP) syndrome, both associated with AKI. The case herein discussed, regarding a 35-year-old woman, who developed AKI and Ogilvie syndrome after a Caesarean section for preeclampsia, may exemplify these diagnostic and therapeutic challenges, and is intended to raise awareness on this unusual complication of Caesarean delivery.

Pathophysiology-Based Management of Acute Heart Failure

Even though acute heart failure (AHF) is one of the most common admission diagnoses globally, its pathogenesis is poorly understood, and there are few effective treatments available. Despite an heterogenous onset, congestion is the leading contributor to hospitalization, making it a crucial therapeutic target. Complete decongestion, nevertheless, may be hard to achieve, especially in patients with reduced end organ perfusion. In order to promote a personalised pathophysiological-based therapy for patients with AHF, we will address in this review the pathophysiological principles that underlie the clinical symptoms of AHF as well as examine how to assess them in clinical practice, suggesting that gaining a deeper understanding of pathophysiology might result in significant improvements in HF therapy.

1,2-Bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic Acid Acetoxymethyl Ester Loaded Reactive Oxygen Species Responsive Hyaluronic Acid-Bilirubin Nanoparticles for Acute Kidney Injury Therapy via Alleviating Calcium Overload Mediated Endoplasmic Reticulum Stress

Calcium overload is one of the early determinants of the core cellular events that contribute to the pathogenesis of acute kidney injury (AKI), which include oxidative stress, ATP depletion, calcium overload, and inflammatory response with self-amplifying and interactive feedback loops that ultimately lead to cellular injury and renal failure. Excluding adjuvant therapy, there are currently no approved pharmacotherapies for the treatment of AKI. Using an adipic dihydride linker, we modified the hyaluronic acid polymer chain with a potent antioxidant, bilirubin, to produce an amphiphilic conjugate. Subsequently, we developed a kidney-targeted and reactive oxygen species (ROS)-responsive drug delivery system based on the flash nanocomplexation method to deliver a well-known intracellular calcium chelator, 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM, BA), with the goal of rescuing renal cell damage via rapidly scavenging of intracellularly overloaded Ca²⁺. In the ischemia-reperfusion (I/R) induced AKI rat model, a single dose of as-prepared formulation (BA 100 μg·kg^-1) 6 h post-reperfusion significantly reduced renal function indicators by more than 60% within 12 h, significantly alleviated tissular pathological changes, ameliorated tissular oxidative damage, significantly inhibited apoptosis of renal tubular cells and the expression of renal tubular marker kidney injury molecule 1, etc., thus greatly reducing the risk of kidney failure. Mechanistically, the treatment with BA-loaded NPs significantly inhibited the activation of the ER stress cascade response (IRE1-TRAF2-JNK, ATF4-CHOP, and ATF6 axis) and regulated the downstream apoptosis-related pathway while also reducing the inflammatory response. The BA-loaded NPs hold great promise as a potential therapy for I/R injury-related diseases.

Abdominal Compartment Syndrome in Acute Pancreatitis: A Narrative Review

Abdominal compartment syndrome (ACS) represents a severe complication of acute pancreatitis (AP), resulting from an acute and sustained increase in abdominal pressure >20 mmHg, in association with new organ dysfunction. The harmful effect of high intra-abdominal pressure on regional and global perfusion results in significant multiple organ failure and is associated with increased morbidity and mortality. There are several deleterious consequences of elevated intra-abdominal pressure on end-organ function, including respiratory, cardiovascular, gastrointestinal, neurologic, and renal effects. It is estimated that about 15% of patients with severe AP develop intra-abdominal hypertension or ACS, with a mortality rate around 50%. The treatment of abdominal compartment syndrome in acute pancreatitis begins with medical intervention and percutaneous drainage, where possible. Abdominal compartment syndrome unresponsive to conservatory treatment requires immediate surgical decompression, along with vacuum-assisted closure therapy techniques, followed by early abdominal fascia closure.

β-lactam precision dosing in critically ill children: Current state and knowledge gaps

There has been emerging interest in implementing therapeutic drug monitoring and model-informed precision dosing of β-lactam antibiotics in critically ill patients, including children. Despite a position paper endorsed by multiple international societies that support these efforts in critically ill adults, implementation of β-lactam precision dosing has not been widely adopted. In this review, we highlight what is known about β-lactam antibiotic pharmacokinetics and pharmacodynamics in critically ill children. We also define the knowledge gaps that present barriers to acceptance and implementation of precision dosing of β-lactam antibiotics in critically ill children: a lack of consensus on which subpopulations would benefit most from precision dosing and the uncertainty of how precision dosing changes outcomes. We conclude with opportunities for further research to close these knowledge gaps.

Fluid management in acute kidney injury: from evaluating fluid responsiveness towards assessment of fluid tolerance

Despite the widespread use of intravenous fluids in acute kidney injury (AKI), solid evidence is lacking. Intravenous fluids mainly improve AKI due to true hypovolaemia, which is difficult to discern at the bedside unless it is very pronounced. Empiric fluid resuscitation triggered only by elevated serum creatinine levels or oliguria is frequently misguided, especially in the presence of fluid intolerance syndromes such as increased extravascular lung water, capillary leak, intra-abdominal hypertension, and systemic venous congestion. While fluid responsiveness tests clearly identify patients who will not benefit from fluid administration (i.e. those without an increase in cardiac output), the presence of fluid responsiveness does not guarantee that fluid therapy is indicated or even safe. This review calls for more attention to the concept of fluid tolerance, incorporating it into a practical algorithm with systematic venous Doppler ultrasonography assessment to use at the bedside, thereby lowering the risk of detrimental kidney congestion in AKI.