Point-of-care urine albumin:creatinine ratio is associated with outcome in emergency department patients with sepsis: a pilot study

Association between proteinuria trajectories and outcomes in critically ill patients with sepsis or shock

Background

Proteinuria results from kidney damage and can be a predictor of illness severity and mortality in the intensive care unit (ICU). However, the optimal timing of proteinuria measurements and the reference values remain undetermined. Our objective was to identify the patterns of proteinuria change associated with mortality in ICU patients with sepsis or shock.

Methods

This monocentric retrospective cohort study performed from April 2010 to April 2018 involved all ICU patients with sepsis or shock and at least two measurements of proteinuria from a 24h-urine collection during the first 10 days of ICU stay, the first of which was made within 48h after ICU admission. We identified proteinuria trajectories by a semi-parametric mixture model and analysed the association between the trajectories and the mortality at day 28 by Cox proportional-hazards model.

Results

A total of 3,344 measurements of proteinuria from 659 patients were analysed. Four proteinuria trajectories were identified. Trajectories 1, 2, 3 and 4 comprised 127, 421, 60 and 51 patients, and were characterized by a first proteinuria of 1.14 [0.66–1.55], 0.52 [0.26–0.91], 2.92 [2.38–3.84] and 2.58 [1.75–3.32] g/24h (p<0.001) and a mortality of 24.4%, 38%, 20% and 43% (p = 0.002), respectively. Trajectories 3 and 4 had a high first proteinuria (>2g/24h). Only, the proteinuria of trajectory 4 increased within 3 days following the first measurement and was associated with increased mortality at day 28 (hazard ratio: 2.36 95%CI [1.07–5.19], p = 0.03), regardless of acute renal failure. The factors associated with trajectory 4 were cancer (relative risk: 8.91 95%CI [2.09–38.02], p = 0.003) and use of inotropic drugs (relative risk: 0.17 95%CI [0.04–0.69], p = 0.01).

Conclusion

This exploratory study of ICU patients with sepsis or shock identified four proteinuria trajectories with distinct patterns of proteinuria change over time and mortality rates. These results provide novel insights into renal pathophysiology and may be helpful to investigate subphenotypes of kidney injury among ICU patients in future studies.

Role of Microalbuminuria and Hypoalbuminemia as Outcome Predictors in Critically Ill Patients

Background

Assessment of microalbuminuria and hypoalbuminemia can be used as a good tool for the prediction of the ICU outcome in critically ill patients.

Purpose

To evaluate and compare the prognostic significance of microalbuminuria (albumin creatinine ratio (ACR)) and serum albumin level done on admission and after twenty-four hours for the critically ill patients. Methodology. Sixty ICU patients were involved in a prospective cohort study (mean age was 44.4 ± 16.7 years, and 78.3% were males). Patients were divided into 2 groups according to mortality (survivors and nonsurvivors) and were subjected to laboratory measurement of the mentioned biomarkers on admission and after twenty-four hours.

Results

There were 34 patients (56.67%) in group A (survivors) and 26 patients (43.33%) in group B (nonsurvivors). Albumin creatinine ratio on admission (ACR1) and albumin creatinine ratio after 24 hours (ACR2) were significantly lower in survivors than nonsurvivors (P values were <0.001 for both). Serum albumin level after 24 hours of admission was significantly higher in survivors than nonsurvivors (P value 0.02) while admission serum albumin was not significantly different between both groups (P value was 0.1). There was a positive correlation between ACR2 and ICU stay and mechanical ventilatory support with a strong positive correlation with the use of vasopressor therapy (r: 0.35, 0.58, and 0.73, respectively). P values were 0.005, <0.0001, and <0.0001, respectively. There was a positive correlation between ACR2 with APACHE II and SOFA scores (r: 0.46 and 0.43, respectively); P values were 0.001 and <0.0001, respectively. There was a moderate negative correlation between serum albumin on admission and after 24 hours and the duration of mechanical ventilation (r: −0.4 and −0.39, respectively) (P values were 0.001 and 0.002, respectively). By Cox regression analysis, two parameters were found to be an independent predictor of mortality in ICU patients which were age and using vasopressor treatment (P values = 0.01 and <0.001), while the other parameters were not independent predictors of mortality (P values were more than 0.05).

Conclusions

Microalbuminuria on admission and after 24 hours of ICU admission could be a good predictor of mortality in critically ill patients. The serum albumin level after 24 hours of admission can predict poor outcomes in critically ill patients.

Association of Urinary Albumin:Creatinine Ratio with Outcome of Children with Sepsis

Objective

The aim of the study was to investigate the association of urinary albumin:creatinine ratio (ACR) with regard to the outcome of sepsis patients and to study the trends of ACR with severity of disease, organ dysfunction, microcirculation status, the use of inotrope, and mechanical ventilation use, and length of pediatric intensive care unit (PICU) stay.

Materials and methods

In the prospective observational study, the patients with varying categories of sepsis admitted in the PICU with stay >24 hours were enrolled consecutively. Urine samples were collected at the time of admission (ACR1), 12 hours (ACR2), and 24 hours (ACR3).

Results

One hundred and thirty-eight patients including 56 cases of sepsis, 31 of severe sepsis, 22 of septic shock, and 29 of multiorgan dysfunction syndrome (MODS) cases were analyzed. There were 29 (21%) deaths. ACR (median, IQR) was significantly higher in nonsurvivors [ACR1 198.9 (111.2–329.4) vs 124.5 (59.37–294.5), p 0.03], [ACR2 213.8 (112.5–350) vs 117.8 (62.6–211.9) p 0.008], [ACR3 231.8 (99.9–441.2 vs 114.4 (44.1–240.3), p 0.005]. The ACR is increased progressively with the increasing severity of sepsis (p < 0.001). The performance of ACR operative characteristics was compared with that of PRISM and PELOD scores. In deceased, ACR was significantly correlated with blood pH, lactate, and base deficit. A cutoff value of ACR 102.7 mg/g had sensitivity 86.2%, specificity 40.4%, positive predictive value 27.8%, and negative predictive value 91.7%. The use of inotropes, mechanical ventilation (>48 hours), and mortality was significantly higher in patients with ACR >102 mg/g. The probability of death varied from 17.6 to 19% in the first 24 hours of admission. ACR was significantly cheaper as compared to PRISM score and PELOD score estimations.

Conclusion

Urinary ACR, a cost-effective tool, correlates with the severity of sepsis and associated morbidity and mortality in children.

How to cite this article

Sachdev A, Raheja K, Gupta N, Chugh P. Association of Urinary Albumin:Creatinine Ratio with Outcome of Children with Sepsis. Indian J Crit Care Med 2020;24(6):465–472.

TLR-mediated albuminuria needs TNFα-mediated cooperativity between TLRs present in hematopoietic tissues and CD80 present on non-hematopoietic tissues in mice

Transient albuminuria induced by pathogen-associated molecular patterns (PAMPs) in mice through engagement of Toll-like receptors (TLRs) is widely studied as a partial model for some forms of human nephrotic syndrome (NS). In addition to TLRs, CD80 has been shown to be essential for PAMP-mediated albuminuria. However, the mechanistic relationships between TLRs, CD80 and albuminuria remain unclear. Here, we show that albuminuria and CD80-uria induced in mice by many TLR ligands are dependent on the expression of TLRs and their downstream signalling intermediate MyD88 exclusively in hematopoietic cells and, conversely, on CD80 expression exclusively in non-hematopoietic cells. TNFα is crucial for TLR-mediated albuminuria and CD80-uria, and induces CD80 expression in cultured renal podocytes. IL-10 from hematopoietic cells ameliorates TNFα production, albuminuria and CD80-uria but does not prevent TNFα-mediated induction of podocyte CD80 expression. Chitohexaose, a small molecule originally of parasite origin, mediates TLR4-dependent anti-inflammatory responses, and blocks TLR-mediated albuminuria and CD80-uria through IL-10. Thus, TNFα is a prominent mediator of renal CD80 induction and resultant albuminuria in this model, and small molecules modulating TLR-mediated inflammatory activation might have contributory or adjunct therapeutic potential in some contexts of NS development.

Summary: Systemic TNFα mediates myeloid cell and podocyte cross-talk to cause LPS-induced mouse microalbuminuria, a partial model of human nephrotic syndrome, pointing to potential adjunct therapeutic approaches.

The importance of microalbuminuria in predicting patient outcome in a PICU

OBJECTIVE

To evaluate the prognostic significance of microalbuminuria in critically ill children.

DESIGN

Prospective study.

SETTING

PICU of a teaching hospital.

PATIENTS

Admitted critically ill children.

INTERVENTIONS

The urine albumin-creatinine ratio was measured at admission and at 24 hours. Pediatric Risk of Mortality, Pediatric Index of Mortality II, Pediatric Logistic Organ Dysfunction, and Inotrope Score were calculated.

MEASUREMENTS AND MAIN RESULTS

In total, 102 patients (median age, 19 mo) were included in the study, among whom were 30 mortalities. Microalbuminuria was identified in 62 patients (64%). The patients were classified into three groups: patients with sepsis, patients with noninfectious systemic inflammatory response syndrome, and patients without systemic inflammatory response syndrome. The highest clinical scores, albumin-creatinine ratio levels, mortality rate, and duration of mechanical ventilation were found in the sepsis group, and the lowest values were seen in patients without systemic inflammatory response syndrome (p < 0.05). Significant correlations were observed between the albumin-creatinine ratio levels and the clinical scores (p < 0.05). The receiver operating characteristics curve analysis showed that the areas under the curves were 0.818 and 0.781, respectively, for albumin-creatinine ratio measured at admission and at 24 hours to identify PICU mortality. At a cutoff value of 34.2 mg/g, albumin-creatinine ratio measured at admission may be able to discriminate between patients a with sensitivity of 63.3%, specificity of 93.3%, positive predictive value of 95%, and negative predictive value of 56%.

CONCLUSIONS

Microalbuminuria is a simple, inexpensive, and useful tool for predicting mortality and morbidity in critically ill children in the PICU.

Galactofuranose-rich polysaccharides from Trebouxia sp. induce inflammation and exacerbate lethality by sepsis in mice

Trebouxia sp. is a genus of green algae that is a symbiotic partner of lichenized fungi. Previous studies conduced demonstrated that Trebouxia sp. is able to produce galactofuranose-rich polysaccharides (β-d-galactofuranan, mannogalactofuranan), which were able to activate macrophages in vitro. The present study was proposed to investigate the effects of SK10 polysaccharides fraction from Trebouxia sp. on the model of polymicrobial sepsis induced by cecal ligation and puncture in mice in vivo. The subcutaneous administration of SK10 increased the late mortality rate by 20%, stimulated neutrophil accumulation in lungs (indirectly measured through myeloperoxidase activity) and also Interleukin-1β, creatinine and glucose serum levels. Moreover this study demonstrates the in vivo proinflammatory effects of polymers of galactofuranose and that they can act as pathogen-associated molecular patterns being highly recognized by the immune system of mammals, even if they come from a non-pathogenic microorganism.

Assessment of microalbuminuria for early diagnosis and risk prediction in dengue infections

BACKGROUND

Dengue is the most important arboviral infection of humans. Following an initial febrile period, a small proportion of infected patients develop a vasculopathy, with children at particular risk for severe vascular leakage and shock. Differentiation between dengue and other common childhood illnesses is difficult during the early febrile phase, and risk prediction for development of shock is poor. The presence of microalbuminuria is recognized as a useful early predictor for subsequent complications in a number of other disorders with vascular involvement. Significant proteinuria occurs in association with dengue shock syndrome and it is possible that early-phase microalbuminuria may be helpful both for diagnosis of dengue and for identification of patients likely to develop severe disease.

METHODOLOGY/PRINCIPAL FINDINGS

We measured formal urine albumin to creatinine ratios (UACRs) in daily samples obtained from a large cohort of children with suspected dengue recruited at two outpatient clinics in Ho Chi Minh City, Vietnam. Although UACRs were increased in the 465 confirmed dengue patients, with a significant time trend showing peak values around the critical period for dengue-associated plasma leakage, urine albumin excretion was also increased in the comparison group of 391 patients with other febrile illnesses (OFI). The dengue patients generally had higher UACRs than the OFI patients, but microalbuminuria, using the conventional cutoff of 30 mg albumin/g creatinine discriminated poorly between the two diagnostic groups in the early febrile phase. Secondly UACRs did not prove useful in predicting either development of warning signs for severe dengue or need for hospitalization.

CONCLUSION/SIGNIFICANCE

Low-level albuminuria is common, even in relatively mild dengue infections, but is also present in many OFIs. Simple point-of-care UACR tests are unlikely to be useful for early diagnosis or risk prediction in dengue endemic areas.