Adrenomedullin surges are linked to acute episodes of the systemic capillary leak syndrome (Clarkson disease)

A Focus on the Pathophysiology of Adrenomedullin Expression: Endothelitis and Organ Damage in Severe Viral and Bacterial Infections

Adrenomedullin (ADM) is a peptide hormone produced primarily in the adrenal glands, playing a crucial role in various physiological processes. As well as improving vascular integrity and decreasing vascular permeability, ADM acts as a vasodilator, positive inotrope, diuretic, natriuretic and bronchodilator, antagonizing angiotensin II by inhibiting aldosterone secretion. ADM also has antihypertrophic, anti-apoptotic, antifibrotic, antioxidant, angiogenic and immunoregulatory effects and antimicrobial properties. ADM expression is upregulated by hypoxia, inflammation-inducing cytokines, viral or bacterial substances, strength of shear stress, and leakage of blood vessels. These pathological conditions are established during systemic inflammation that can result from infections, surgery, trauma/accidents or burns. The ability to rapidly identify infections and the prognostic, predictive power makes it a valuable tool in severe viral and bacterial infections burdened by high incidence and mortality. This review sheds light on the pathophysiological processes that in severe viral or bacterial infections cause endothelitis up to the development of organ damage, the resulting increase in ADM levels dosed through its more stable peptide mid-regional proadrenomedullin (MR-proADM), the most significant studies that attest to its diagnostic and prognostic accuracy in highlighting the severity of viral or bacterial infections and appropriate therapeutic insights.

Ultrasound findings and specific intrinsic blood volume expansion therapy for neonatal capillary leak syndrome: report from a multicenter prospective self-control study

OBJECTIVE

Capillary leak syndrome (CLS) is characterized by severe systemic edema without specific treatment, resulting in a high mortality rate. This study investigated whether there is organ edema in neonatal CLS patients and specific treatment strategies to improve patient prognosis.

METHODS

Thirty-seven newborns diagnosed with CLS were included in this study. (1) Routine point-of-care ultrasound (POCUS) was used to identify whether the patients had visceral edema or fluid collection. (2) All patients were treated with 3% NaCl intravenously, and the clinical manifestations, laboratory indices and outcomes were compared before and after treatment.

RESULTS

(1) Diffuse severe edema was found in 92.0% of the patients. (2) The POCUS examination revealed that CLS patients exhibited significant visceral edema in addition to diffuse severe edema, which included pulmonary edema in 67.6%, cerebral edema in 37.8%, severe intestinal edema in 24.3%, severe myocardial edema in 8.1%, pericardial effusion in 5.4%, pleural effusion in 29.7% and peritoneal effusion in 18.9%. Two patients (5.45%) had only myocardial edema without other manifestations. (3) Before and after the intravenous injection of 3% NaCl, there were no significant differences in the serum sodium or potassium levels of CLS patients, while the hemoglobin and hematocrit levels were significantly lower after treatment (p < 0.01). Her plasma ALB concentration and arterial pressure returned to normal levels after the treatment was completed. (4) All the patients survived, and no side effects or complications were observed during or after treatment with 3% NaCl.

CONCLUSIONS

(1) In addition to diffuse severe edema, visceral edema and effusion are common and important clinical manifestations of neonatal CLS and need to be detected by routine POCUS. (2) The intravenous injection of 3% NaCl is a safe, effective and specific treatment strategy for neonatal CLS, with a survival rate of 100% and no adverse effects.

Mid-Regional Pro-Adrenomedullin Can Predict Organ Failure and Prognosis in Sepsis?

Sepsis causes immune dysregulation and endotheliitis, with an increase in mid-regional pro-adrenomedullin (MR-proADM). The aim of the study is to determine an MR-proADM value that, in addition to clinical diagnosis, can identify patients with localized infection or those with sepsis/septic shock, with specific organ damage or with the need for intensive care unit (ICU) transfer and prognosis. The secondary aim is to correlate the MR-proADM value with the length of stay (LOS). In total, 301 subjects with sepsis (124/301 with septic shock) and 126 with localized infection were retrospectively included. In sepsis, MR-proADM ≥ 3.39 ng/mL identified acute kidney injury (AKI); ≥2.99 ng/mL acute respiratory distress syndrome (ARDS); ≥2.28 ng/mL acute heart failure (AHF); ≥2.55 ng/mL Glascow Coma Scale (GCS) < 15; ≥3.38 multi-organ involvement; ≥3.33 need for ICU transfer; ≥2.0 Sequential Organ Failure Assessment (SOFA) score ≥ 2; and ≥3.15 ng/mL non-survivors. The multivariate analysis showed that MR-proADM ≥ 2 ng/mL correlates with AKI, anemia and SOFA score ≥ 2, and MR-proADM ≥ 3 ng/mL correlates with AKI, GCS < 15 and SOFA score ≥ 2. A correlation between mortality and AKI, GCS < 15, ICU transfer and cathecolamine administration was found. In localized infection, MR-proADM at admission ≥ 1.44 ng/mL identified patients with AKI; ≥1.0 ng/mL with AHF; and ≥1.44 ng/mL with anemia and SOFA score ≥ 2. In the multivariate analysis, MR-proADM ≥ 1.44 ng/mL correlated with AKI, anemia, SOFA score ≥ 2 and AHF. MR-proADM is a marker of oxidative stress due to an infection, reflecting severity proportionally to organ damage.

A ligand-independent Tie2-activating antibody reduces vascular leakage in models of Clarkson disease

Vascular dysfunction resulting from endothelial hyperpermeability is a common and important feature of critical illness due to sepsis, trauma, and other conditions associated with acute systemic inflammation. Clarkson disease [monoclonal gammopathy-associated idiopathic systemic capillary leak syndrome (ISCLS)] is a rare, orphan disorder marked by spontaneous and recurrent episodes of hypotensive shock and peripheral edema due to widespread vascular leakage in peripheral tissues. Mortality from acute flares approaches 30% due to lack of effective therapies. We evaluated a monoclonal antibody (4E2) specific for the endothelial receptor tyrosine kinase Tie2 in ISCLS models. 4E2 activated Tie2 in ISCLS patient-derived endothelial cells and reduced baseline and proinflammatory mediator-induced barrier dysfunction. 4E2 also reduced mortality and/or vascular leakage associated with systemic histamine challenge or influenza infection in the SJL/J mouse model of ISCLS. These findings support a critical role for Tie2 dysregulation in ISCLS and highlight a viable therapeutic approach to this catastrophic disorder.

Use of Biomarkers to Improve 28-Day Mortality Stratification in Patients with Sepsis and SOFA ≤ 6

Early diagnosis and appropriate treatments are crucial to reducing mortality risk in septic patients. Low SOFA scores and current biomarkers may not adequately discern patients that could develop severe organ dysfunction or have an elevated mortality risk. The aim of this prospective observational study was to evaluate the predictive value of the biomarkers mid-regional pro-adrenomedullin (MR-proADM), procalcitonin (PCT), C-reactive protein (CRP), and lactate for 28-day mortality in patients with sepsis, and patients with a SOFA score ≤6. 284 were included, with a 28-day all-cause mortality of 8.45% (n = 24). Non-survivors were older (p = 0.003), required mechanical ventilation (p = 0.04), were ventilated for longer (p = 0.02), and had higher APACHE II (p = 0.015) and SOFA (p = 0.027) scores. Lactate showed the highest predictive ability for all-cause 28-day mortality, with an area under the receiver-operating characteristic curve (AUROC) of 0.67 (0.55-0.79). The AUROC for all-cause 28-day mortality in patients with community-acquired infection was 0.69 (0.57-0.84) for SOFA and 0.70 (0.58-0.82) for MR-proADM. A 2.1 nmol/L cut-off point for this biomarker in this subgroup of patients discerned, with 100% sensibility, survivors from non-survivors at 28 days. In patients with community-acquired sepsis and initial SOFA score ≤ 6, MR-proADM could help identify patients at risk of 28-day mortality.

Mid-regional proadrenomedullin (MR-proADM), C-reactive protein (CRP) and other biomarkers in the early identification of disease progression in patients with COVID-19 in the acute NHS setting

AIMS

There is a lack of biomarkers validated for assessing clinical deterioration in patients with COVID-19 on presentation to secondary or tertiary care. This evaluation looked at the potential clinical application of C reactive protein (CRP), procalcitonin, mid-regional proadrenomedullin (MR-proADM) and white cell count to support prediction of clinical outcomes.

METHODS

135 patients presenting to Hampshire Hospitals NHS Foundation Trust between April and June 2020 confirmed to have COVID-19 via reverse-transcription-qPCR were included. Biomarkers from within 24 hours of presentation were used to predict disease progression by Cox regression and area under the receiver operating characteristic curves. The endpoints assessed were 30-day all-cause mortality, intubation and ventilation, critical care admission and non-invasive ventilation (NIV) use.

RESULTS

Elevated MR-proADM was shown to have the greatest ability to predict 30-day mortality adjusting for age, cardiovascular disease, renal disease and neurological disease. A significant association was also noted between raised MR-proADM and CRP concentrations and the requirement for critical care admission and NIV.

CONCLUSIONS

The measurement of MR-proADM and CRP in patients with confirmed COVID-19 infection on admission shows significant potential to support clinicians in identifying those at increased risk of disease progression and need for higher level care, subsequently enabling prompt escalation in clinical interventions.

Circulating mid-regional proadrenomedullin is a predictor of mortality in patients with COVID-19: a systematic review and meta-analysis

BACKGROUND

Although there is increasing understanding of the changes in the laboratory parameters of Coronavirus disease 2019 (COVID-19), the correlation between circulating Mid-regional Proadrenomedullin (MR-proADM) and mortality of patients with COVID-19 is not fully understood. In this study, we conducted a systematic review and meta-analysis to evaluate the prognostic value of MR-proADM in patients with COVID-19.

METHODS

The PubMed, Embase, Web of Science, Cochrane Library, Wanfang, SinoMed and Chinese National Knowledge Infrastructure (CNKI) databases were searched from 1 January 2020 to 20 March 2022 for relevant literature. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used to assess quality bias, STATA was employed to pool the effect size by a random effects model, and potential publication bias and sensitivity analyses were performed.

RESULTS

14 studies comprising 1822 patients with COVID-19 met the inclusion criteria, there were 1145 (62.8%) males and 677 (31.2%) females, and the mean age was 63.8 ± 16.1 years. The concentration of MR-proADM was compared between the survivors and non-survivors in 9 studies and the difference was significant (P < 0.01), I² = 46%. The combined sensitivity was 0.86 [0.73-0.92], and the combined specificity was 0.78 [0.68-0.86]. We drew the summary receiver operating characteristic (SROC) curve and calculated the area under curve (AUC) = 0.90 [0.87-0.92]. An increase of 1 nmol/L of MR-proADM was independently associated with a more than threefold increase in mortality (odds ratio (OR) 3.03, 95% confidence interval (CI) 2.26-4.06, I² = 0.0%, P = 0.633). The predictive value of MR-proADM for mortality was better than many other biomarkers.

CONCLUSION

MR-proADM had a very good predictive value for the poor prognosis of COVID-19 patients. Increased levels of MR-proADM were independently associated with mortality in COVID-19 patients and may allow a better risk stratification.

Circulating dipeptidyl peptidase 3 and bio-adrenomedullin levels are associated with impaired outcomes in critically ill COVID-19 patients: a prospective international multicentre study

Introduction

Dipeptidyl peptidase-3 (DPP3) is a protease involved in the degradation of several cardiovascular mediators. Adrenomedullin (bio-ADM) is a peptide essential for regulation of endothelial barrier function. In different shock-pathologies, both biomarkers are associated with disease severity, organ dysfunction and mortality. Associations with outcome in critically ill COVID-19 patients are unknown. The objectives of the present study were to investigate associations of bio-ADM and "circulating DPP3" (cDPP3) with short-term outcome in critically ill COVID-19 patients (n=80).

Methods

A multicentre prospective cohort study was performed. The primary end-point was 28-day mortality. Secondary end-points included different severities of acute kidney injury (AKI).

Results

cDPP3 levels were mainly associated with 28-day mortality; Area under the receiver operating characteristics (AUROCs) of 0.69 (0.56-0.82, p=0.023), 0.77 (0.64-0.90, p<0.001) and 0.81 (0.65-0.96, p<0.001) at admission, day 3 and day 7, respectively. In contrast, bio-ADM levels were mainly associated with AKI, with AUROCs of 0.64 (0.51-0.77, p=0.048), 0.75 (0.64-0.86, p<0.001) and 0.83 (0.74-0.93, p<0.001) for day 1, 3 and 7, respectively. Interestingly, patients with high levels of both cDPP3 and bio-ADM at day 7 had an additionally increased risk of 28-day mortality (hazard ratio 11.8; 95% CI 2.5-55.3, p<0.001).

Conclusions

cDPP3 and bio-ADM responses were associated with short-term mortality and AKI in critically ill COVID-19 patients, respectively. These findings suggest that treatment with specific antibodies modulating cDPP3 or bio-ADM-related pathways may improve outcome of COVID-19.

Mid-regional Proadrenomedullin Biomarker Predicts Coronavirus Disease 2019 Clinical Outcomes: A US-Based Cohort Study

Background

Mid-regional proadrenomedullin (MR-proADM) is a biomarker released following endothelial damage. Studies have shown a correlation in predicting coronavirus disease 2019 (COVID-19) outcomes with MR-proADM levels. Our study aimed to investigate baseline MR-proADM as a predictor of a wider range of clinical outcomes of varying severity in patients admitted with COVID-19, and to compare to other biomarkers.

Methods

Data from the Boston Area COVID-19 Consortium (BACC) Bay Tocilizumab Trial was used in this study. Patients with biomarker determinations, and not admitted to the intensive care unit (ICU) on admission, were included. MR-proADM cutoff of 0.87 nmol/L was assessed in predicting clinical outcomes.

Results

Of 182 patients, 11.0% were mechanically ventilated or dead within 28 days. Of patients with MR-proADM >0.87 nmol/L, 21.1% were mechanically ventilated or dead within 28 days, compared with 4.5% of those with MR-proADM ≤0.87 nmol/L (P < .001). The sensitivity, specificity, negative predictive value, and positive predictive value of MR-proADM cutoff of 0.87 nmol/L in predicting mechanical ventilation or death were 75%, 65%, 95%, and 21%, respectively, with an area under the receiver operating characteristic curve of 0.76. On multivariable logistic regression analysis, MR-proADM >0.87 nmol/L was independently associated with mechanical ventilation or death, ICU admission, prolonged hospitalization beyond day 4, and day 4 COVID-19 ordinal scale equal to or worse than day 1.

Conclusions

MR-proADM functions as a valuable biomarker for the early risk stratification and detection of severe disease progression of patients with COVID-19. In the prediction of death, MR-proADM performed better compared to many other commonly used biomarkers.

Identification of COVID-19 patients at risk of hospital admission and mortality: a European multicentre retrospective analysis of mid-regional pro-adrenomedullin

Background

Mid-Regional pro-Adrenomedullin (MR-proADM) is an inflammatory biomarker that improves the prognostic assessment of patients with sepsis, septic shock and organ failure. Previous studies of MR-proADM have primarily focussed on bacterial infections. A limited number of small and monocentric studies have examined MR-proADM as a prognostic factor in patients infected with SARS-CoV-2, however there is need for multicenter validation. An evaluation of its utility in predicting need for hospitalisation in viral infections was also performed.

Methods

An observational retrospective analysis of 1861 patients, with SARS-CoV-2 confirmed by RT-qPCR, from 10 hospitals across Europe was performed. Biomarkers, taken upon presentation to Emergency Departments (ED), clinical scores, patient demographics and outcomes were collected. Multiclass random forest classifier models were generated as well as calculation of area under the curve analysis. The primary endpoint was hospital admission with and without death.

Results

Patients suitable for safe discharge from Emergency Departments could be identified through an MR-proADM value of ≤ 1.02 nmol/L in combination with a CRP (C-Reactive Protein) of ≤ 20.2 mg/L and age ≤ 64, or in combination with a SOFA (Sequential Organ Failure Assessment) score < 2 if MR-proADM was ≤ 0.83 nmol/L regardless of age. Those at an increased risk of mortality could be identified upon presentation to secondary care with an MR-proADM value of > 0.85 nmol/L, in combination with a SOFA score ≥ 2 and LDH > 720 U/L, or in combination with a CRP > 29.26 mg/L and age ≤ 64, when MR-proADM was > 1.02 nmol/L.

Conclusions

This international study suggests that for patients presenting to the ED with confirmed SARS-CoV-2 infection, MR-proADM in combination with age and CRP or with the patient’s SOFA score could identify patients at low risk where outpatient treatment may be safe.

A deadly capillary leak attack. Clarkson's disease: a narrative review

A previously 42-year-old healthy man was brought in by an ambulance to the emergency department with symptoms of a distributive shock. He experienced a rapid decline in his clinical state that evolved into a cardiac arrest. Despite all the performed measures and a prolonged resuscitation, the patient died a few hours later without an initial clear diagnosis. Lab results showed an extremely high haemoconcentration leading to further investigations which suggested the possibility of Clarkson's disease, although septic shock as an alternative diagnosis could not be excluded. Nevertheless, because of its presentation, especially emergency and intensive care physicians should be aware of the existence of this condition in the event of an unexplained refractory distributive shock in combination with haemoconcentration and hypoalbuminemia given its possible fatal outcome.

Systemic capillary leak syndrome following granulocyte colony-stimulating factor therapy in a T-lymphoblastic leukemia/lymphoma patient: a case report

Introduction

Systemic capillary leak syndrome (SCLS) is a rare and often fatal clinical entity used to describe a generalized increase in vascular permeability leading to fluid extravasation toward the interstitial compartment. SCLS could be an idiopathic disease or secondary to infections, malignancies or drugs.

Case

We present a case of presumably granulocyte colony-stimulating factor (G-CSF)-induced SCLS in a 21-year-old man diagnosed with T‑lymphoblastic leukemia/lymphoma. He received the 6th cycle (part B) of the hyper-CVAD chemotherapeutic regimen followed by the initiation of neutropenic fever prophylaxis protocol which included antibiotics and G‑CSF. In a course of hours, the patient became dyspneic, hypotensive, and edematous which required intensive care unit admission and was stabilized accordingly. In the following days the patient's anasarca progressively increased which was associated with hypoalbuminemia, hypotension and anemia with pericardial and bilateral plural effusions. As a diagnosis of exclusion augmented by the acuity of such clinical event, observed concomitantly with the administration of the prophylaxis protocol, the suspicion of G‑CSF-induced SCLS was established. Consequently, G‑CSF was discontinued and treatment with dexamethasone and intravenous immunoglobulins (IVIG) was started. The patient's condition improved significantly illustrated by hemodynamic stability in addition to improvement regarding the anasarca, hypoalbuminemia, and anemia. Follow-up scans suggest resolution of the pericardial and plural effusions.

Conclusion

SCLS remains a serios and potentially fatal complication of G‑CSF administration which should be taken into consideration, since such medication is widely utilized in oncology wards.

Midregional proadrenomedullin safely reduces hospitalization in a low severity cohort with infections in the ED: a randomized controlled multi-centre interventional pilot study

INTRODUCTION

The midregional fragment of proadrenomedullin (MR-proADM) is known to provide accurate short-, mid- and long term prognostic information in the triage and multi-dimensional risk assessment of patients in the emergency department (ED). In two independent observational cohorts MR-proADM values identified low disease severity patients without risk of disease progression in the ED with no 28 days mortality that wouldn´t require hospitalization. In this interventional study we want to show that the combination of an MR-proADM algorithm with clinical assessment is able to identify low risk patients not requiring hospitalization to safely reduce the number of hospital admissions.

METHODS

A randomized-controlled interventional multicenter study in 4 EDs in Spain. The study protocol was approved by Ethics Committees. Control arm patients received Standard Care. MR-proADM guided arm patients with low MR-proADM value (≤0.87 nmol/L) were treated as out-patients, with high MR-proADM value (>0.87 nmol/L) were hospitalized. The hospitalization rate was compared between the study arms.

RESULTS

Two hundred patients with suspicion of infection were enrolled. In the MR-proADM guided arm the hospital admission rate in the intention-to-treat (ITT) population was 17% lower than in the control arm (40.6% vs. 57.6%, p=0.024) and 20% lower in the per protocol (PP) population (37.2% vs. 57.6%, p=0.009). No deaths of out-patients and no significant difference for the safety endpoints readmission and representation rates were observed. The readmission rate was only slightly higher in the MR-proADM guided arm compared to the control arm (PP population: at 14 days 9.3% vs. 7.1%, difference 2.1% (95% CI: -11.0% to 15.2%); and at 28 days 11.1% vs. 9.5%, difference 1.6% (95% CI: -12.2% to 15.4%)). The rate of 28 days representation was slightly lower in the MR-proADM guided arm compared to the control arm (20.4% vs. 26.2%, difference -5.8% (95% CI: -25.0% to 13.4%); PP population).

CONCLUSIONS

Implementing a MR-proADM algorithm optimizes ED workflows efficiently and sustainably. Hospitals can highly benefit from a reduced rate of hospitalizations by 20% using MR-proADM. The safety in the MR-proADM guided study arm was similar to the Standard Care arm.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT03770533.

[Idiopathic systemic capillary leak syndrome: 2 cases with misleading presentation]

INTRODUCTION

Idiopathic systemic capillary leak syndrome (ISCLS) also known as Clarkson syndrome is a rare and sudden life-threatening entity. Three consecutive phases are described. A first non-specific prodromal phase often manifests as "flu-like" symptoms and precedes capillary leak phase with major hypovolemic and distributive shock leading to serious and frequent multiorgan dysfunction syndrome (MODS). Severe hypovolemia contrasts with edema, and hemoconcentration with hypoalbuminemia. ISCLS is characterized by these two clinical and biological paradoxes. Subsequent recovery phase exhibits organ function restoration along with interstitial/intravascular volumes normalization. The latter occurs spontaneously and systematically in patients surviving from leak phase.

OBSERVATIONS

We report here two ISCLS cases admitted in intensive care unit (ICU) both enhancing initial misdiagnosis possibly lowering prognosis and outcome. Our first 28-year-old female patient was admitted for « polycythemia vera » although hemoconcentration was attributable to hypovolemia. She presented circulatory arrest during the second bloodletting session and complicated with MODS. In and out ICU favorable outcome was noted on intravenous immunoglobulin therapy. A second 57-year-old male patient was admitted in ICU for severe "myositis" (myalgia and rhabdomyolysis) although rectified diagnosis retained compartment syndrome (muscular severe edema following capillary leak). Rapid and refractory hypovolemic shock appeared with subsequent MODS leading to death.

CONCLUSION

ISCLS pathophysiology remains unknown but certainly implies transitory endothelial dysfunction. Impossibility of randomized controlled trial for this exceptional disease led to based-on-experience therapeutic guidelines implying symptomatic care (cardiac output surveillance, nephroprotection, prudent fluid intake, prudent vasoactive amine use) and specific therapies (intravenous aminophylline during severe flares). Although enhancing controversial and even deleterious effects during the acute phase, polyvalent immunoglobulins are effective for relapse prevention. Syndromic diagnosis is difficult, but its precocious finding constitutes a key-element in better outcome before organ failure.

Effectiveness of mid-regional pro-adrenomedullin (MR-proADM) as prognostic marker in COVID-19 critically ill patients: An observational prospective study

OBJECTIVE

To test the effectiveness of mid-regional pro-adrenomedullin (MR-proADM) in comparison to C-reactive protein (CRP), procalcitonin (PCT), D-dimer, lactate dehydrogenase (LDH) in predicting mortality in COVID-19-ICU-patients.

METHODS

All consecutive COVID-19 adult patients admitted between March and June 2020 to the ICU of a referral, university hospital in Northern-Italy were enrolled. MR-proADM and routine laboratory test were measured within 48 hours from ICU admission, on day 3, 7 and 14. Survival curves difference with MR-proADM cut-off set to 1.8 nmol/L were tested using log-rank test. Predictive ability was compared using area under the curve and 95% confidence interval of different receiver-operating characteristics curves.

RESULTS

57 patients were enrolled. ICU and overall mortality were 54.4%. At admission, lymphocytopenia was present in 86% of patients; increased D-dimer and CRP levels were found in 84.2% and 87.7% of patients respectively, while PCT values > 0.5 μg/L were observed in 47.4% of patients. MR-proADM, CRP and LDH were significantly different between surviving and non-surviving patients and over time, while PCT, D-dimer and NT-pro-BNP did not show any difference between the groups and over time; lymphocytes were different between surviving and non-surviving patients only. MR-proADM was higher in dying patients (2.65±2.33vs1.18±0.47, p<0.001) and a higher mortality characterized patients with MR-proADM >1.8 nmol/L (p = 0.016). The logistic regression model adjusted for age, gender, cardiovascular disease, diabetes mellitus and PCT values confirmed an odds ratio = 10.3 [95%CI:1.9-53.6] (p = 0.006) for MR-proADM >1.8 nmol/L and = 22.2 [95%CI:1.6-316.9] (p = 0.022) for cardiovascular disease. Overall, MR-proADM had the best predictive ability (AUC = 0.85 [95%CI:0.78-0.90]).

CONCLUSIONS

In COVID-19 ICU-patients, MR-proADM seems to have constantly higher values in non-survivor patients and predict mortality more precisely than other biomarkers. Repeated MR-proADM measurement may support a rapid and effective decision-making. Further studies are needed to better explain the mechanisms responsible of the increase in MR-proADM in COVID-19 patients.

Rare genetic variants suggest dysregulation of signaling pathways in low- and high-risk patients developing severe ovarian hyperstimulation syndrome

PURPOSE

To investigate if rare gene variants in women with severe ovarian hyperstimulation syndrome (OHSS) provide clues to the mechanisms involved in the syndrome.

METHODS

Among participants in a prospective randomized study (Toftager et al. 2016), six women with predicted low and six women with predicted high risk of OHSS developing severe OHSS (grades 4 and 5, Golan classification) were selected. In the same cohort, six plus six matched controls developing no signs of OHSS (Golan grade 0) were selected. Whole-exome sequencing was performed. Analysis using a predefined in silico OHSS gene panel, variant filtering, and pathway analyses was done.

RESULTS

We found no convincing monogenetic association with the development of OHSS using the in silico gene panel. Pathway analysis of OHSS variant lists showed substantial overlap in highly enriched top pathways (p value range p < 0.0001 and p > 9.8E-17) between the low- and high-risk group developing severe OHSS, i.e., "the integrin-linked kinase (ILK) signaling pathway" and the "axonal guidance signaling pathway," both being connected to vasoactive endothelial growth factor (VEGF) and endothelial function.

CONCLUSION

Rare variants in OHSS cases with two distinct risk profiles enrich the same signaling pathways linked to VEGF and endothelial function. Clarification of the mechanism as well as potentially defining genetic predisposition of the high vascular permeability is important for future targeted treatment and prevention of OHSS; the potential roles of ILK signaling and the axonal guidance signaling need to be validated by functional studies.

Whole-Exome Sequencing of Adult and Pediatric Cohorts of the Rare Vascular Disorder Systemic Capillary Leak Syndrome

OBJECTIVE

Systemic capillary leak syndrome (SCLS) is a rare disorder that presents with episodes of hypovolemic shock. The extent to which genetic abnormalities contribute to SCLS is unknown. We identified pediatric and adult cohorts with characteristic clinical courses. We sought to describe the clinical characteristics of both cohorts, identify a possible genetic contribution to SCLS, and demonstrate that whole-exome sequencing (WES) may be conducted by critical care providers.

DESIGN

Prospective observational study of WES of nine adult and eight pediatric SCLS patients and available unaffected first-degree relatives.

SETTING

Tertiary children's hospitals and referral research laboratory.

PATIENTS

Children and adults with SCLS.

INTERVENTIONS

None.

MEASUREMENTS

Patients and available first-degree relatives underwent WES. Data were analyzed for rare homozygous, biallelic, de novo, and heterozygous variants with allelic enrichment and metabolic pathway analyses.

MAIN RESULTS

Children with SCLS presented at a younger age with episodes similar to those experienced by adults. All patients and available relatives underwent satisfactory WES. No overlapping gene variants or metabolic pathways were identified across all SCLS patients. Multiple candidate genes with homozygous or biallelic mutations were identified in individual subjects with SCLS. There was no significant enrichment of genes with rare heterozygous variants.

CONCLUSIONS

The clinical characteristics of children and adults with SCLS are similar. We did not identify a uniform germline exomic genetic etiology for SCLS. WES identified several candidate genes in individual patients for future research. WES is a viable way for critical care providers to investigate the etiology of diseases with presumed genetic contributions.

Biomarkers and clinical scores to aid the identification of disease severity and intensive care requirement following activation of an in-hospital sepsis code

BACKGROUND

Few validated biomarker or clinical score combinations exist which can discriminate between cases of infection and other non-infectious conditions following activation of an in-hospital sepsis code, as well as provide an accurate severity assessment of the corresponding host response. This study aimed to identify suitable blood biomarker (MR-proADM, PCT, CRP and lactate) or clinical score (SOFA and APACHE II) combinations to address this unmet clinical need.

METHODS

A prospective, observational study of patients activating the Vall d'Hebron University Hospital sepsis code (ISC) within the emergency department (ED), hospital wards and intensive care unit (ICU). Area under the receiver operating characteristic (AUROC) curves, logistic and Cox regression analysis were used to assess performance.

RESULTS

148 patients fulfilled the Vall d'Hebron ISC criteria, of which 130 (87.8%) were retrospectively found to have a confirmed diagnosis of infection. Both PCT and MR-proADM had a moderate-to-high performance in discriminating between infected and non-infected patients following ISC activation, although the optimal PCT cut-off varied significantly across departments. Similarly, MR-proADM and SOFA performed well in predicting 28- and 90-day mortality within the total infected patient population, as well as within patients presenting with a community-acquired infection or following a medical emergency or prior surgical procedure. Importantly, MR-proADM also showed a high association with the requirement for ICU admission after ED presentation [OR (95% CI) 8.18 (1.75-28.33)] or during treatment on the ward [OR (95% CI) 3.64 (1.43-9.29)], although the predictive performance of all biomarkers and clinical scores diminished between both settings.

CONCLUSIONS

Results suggest that the individual use of PCT and MR-proADM might help to accurately identify patients with infection and assess the overall severity of the host response, respectively. In addition, the use of MR-proADM could accurately identify patients requiring admission onto the ICU, irrespective of whether patients presented to the ED or were undergoing treatment on the ward. Initial measurement of both biomarkers might therefore facilitate early treatment strategies following activation of an in-hospital sepsis code.

Biomarkers and clinical scores to identify patient populations at risk of delayed antibiotic administration or intensive care admission

BACKGROUND

The performance of blood biomarkers (mid-regional proadrenomedullin (MR-proADM), procalcitonin (PCT), C-reactive protein (CRP), and lactate) and clinical scores (Sequential Organ Failure Assessment (SOFA), National Early Warning Score (NEWS), and quick SOFA) was compared to identify patient populations at risk of delayed treatment initiation and disease progression after presenting to the emergency department (ED) with a suspected infection.

METHODS

A prospective observational study across three EDs. Biomarker and clinical score values were calculated upon presentation and 72 h, and logistic and Cox regression used to assess the strength of association. Primary outcomes comprised of 28-day mortality prediction and delayed antibiotic administration or intensive care (ICU) admission, whilst secondary outcomes identified subsequent disease progression.

RESULTS

Six hundred eighty-four patients were enrolled with hospitalisation, ICU admission, and infection-related 28-day mortality rates of 72.8%, 3.4%, and 4.4%, respectively. MR-proADM and NEWS had the strongest association with hospitalisation and the requirement for antibiotic administration, whereas MR-proADM alone had the strongest association with ICU admission (OR [95% CI]: 5.8 [3.1 - 10.8]) and mortality (HR [95% CI]: 3.8 [2.2 - 6.5]). Patient subgroups with high MR-proADM concentrations (≥ 1.77 nmol/L) and low NEWS (< 5 points) values had significantly higher rates of ICU admission (8.1% vs 1.6%; p < 0.001), hospital readmission (18.9% vs. 5.9%; p < 0.001), infection-related mortality (13.5% vs. 0.2%; p < 0.001), and disease progression (29.7% vs. 4.9%; p < 0.001) than corresponding patients with low MR-proADM concentrations. ICU admission was delayed by 1.5 [0.25 - 5.0] days in patients with high MR-proADM and low NEWS values compared to corresponding patients with high NEWS values, despite similar 28-day mortality rates (13.5% vs. 16.5%). Antibiotics were withheld in 17.4% of patients with high MR-proADM and low NEWS values, with higher subsequent rates of ICU admission (27.3% vs. 4.8%) and infection-related hospital readmission (54.5% vs. 14.3%) compared to those administered antibiotics during ED treatment.

CONCLUSIONS

Patients with low severity signs of infection but high MR-proADM concentrations had an increased likelihood of subsequent disease progression, delayed antibiotic administration or ICU admission. Appropriate triage decisions and the rapid use of antibiotics in patients with high MR-proADM concentrations may constitute initial steps in escalating or intensifying early treatment strategies.

Key Regulatory Effect of Activated HIF-1α/VEGFA Signaling Pathway in Systemic Capillary Leak Syndrome Confirmed by Bioinformatics Analysis

Systemic capillary leak syndrome (SCLS) is a rare disorder characterized by capillary leakage of plasma fluids throughout the endothelium. The mechanism of SCLS is still unknown. Vascular endothelial growth factor (VEGF), an inducer or barrier disruption, is markedly upregulated in SCLS. This study was to investigate the molecular mechanisms involving SCLS-related inflammation and neuron damage in SCLS remain unclear. Data files of GSE97287 dataset were extracted and processed for identification of differentially expressed genes (DEGs), including upregulated adrenomedullin (ADM) gene, hypoxia-inducible factor-1α (HIF-1α) and VEGFA; and downregulated aldehyde dehydrogenase 1A1 (ALDH1A1) gene and interleukin (IL)-2 receptor β (IL-2RB) gene. Weighted gene coexpression network analysis (WGCNA) was performed for DEGs and four significant modules were identified and were enriched Gene Ontology (GO) biological processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to immune response, angiogenesis, neuroblast proliferation, HIF-1 signaling pathway, and Parkinson's disease. The activated HIF-1α/VEGFA signaling in SCLS patients might well be responsible for the impaired inflammatory, nervous, and immune systems.

Neutrophil activation in systemic capillary leak syndrome (Clarkson disease)

Systemic capillary leak syndrome (SCLS; Clarkson disease) is a rare orphan disorder characterized by transient yet recurrent episodes of hypotension and peripheral oedema due to diffuse vascular leakage of fluids and proteins into soft tissues. Humoral mediators, cellular responses and genetic features accounting for the clinical phenotype of SCLS are virtually unknown. Here, we searched for factors altered in acute SCLS plasma relative to matched convalescent samples using multiplexed aptamer‐based proteomic screening. Relative amounts of 612 proteins were changed greater than twofold and 81 proteins were changed at least threefold. Among the most enriched proteins in acute SCLS plasma were neutrophil granule components including bactericidal permeability inducing protein, myeloperoxidase and matrix metalloproteinase 8. Neutrophils isolated from blood of subjects with SCLS or healthy controls responded similarly to routine pro‐inflammatory mediators. However, acute SCLS sera activated neutrophils relative to remission sera. Activated neutrophil supernatants increased permeability of endothelial cells from both controls and SCLS subjects equivalently. Our results suggest systemic neutrophil degranulation during SCLS acute flares, which may contribute to the clinical manifestations of acute vascular leak.

The early identification of disease progression in patients with suspected infection presenting to the emergency department: a multi-centre derivation and validation study

Background

There is a lack of validated tools to assess potential disease progression and hospitalisation decisions in patients presenting to the emergency department (ED) with a suspected infection. This study aimed to identify suitable blood biomarkers (MR-proADM, PCT, lactate and CRP) or clinical scores (SIRS, SOFA, qSOFA, NEWS and CRB-65) to fulfil this unmet clinical need.

Methods

An observational derivation patient cohort validated by an independent secondary analysis across nine EDs. Logistic and Cox regression, area under the receiver operating characteristic (AUROC) and Kaplan-Meier curves were used to assess performance. Disease progression was identified using a composite endpoint of 28-day mortality, ICU admission and hospitalisation > 10 days.

Results

One thousand one hundred seventy-five derivation and 896 validation patients were analysed with respective 28-day mortality rates of 7.1% and 5.0%, and hospitalisation rates of 77.9% and 76.2%. MR-proADM showed greatest accuracy in predicting 28-day mortality and hospitalisation requirement across both cohorts. Patient subgroups with high MR-proADM concentrations (≥ 1.54 nmol/L) and low biomarker (PCT < 0.25 ng/mL, lactate < 2.0 mmol/L or CRP < 67 mg/L) or clinical score (SOFA < 2 points, qSOFA < 2 points, NEWS < 4 points or CRB-65 < 2 points) values were characterised by a significantly longer length of hospitalisation (p < 0.001), rate of ICU admission (p < 0.001), elevated mortality risk (e.g. SOFA, qSOFA and NEWS HR [95%CI], 45.5 [10.0–207.6], 23.4 [11.1–49.3] and 32.6 [9.4–113.6], respectively) and a greater number of disease progression events (p < 0.001), compared to similar subgroups with low MR-proADM concentrations (< 1.54 nmol/L). Increased out-patient treatment across both cohorts could be facilitated using a derivation-derived MR-proADM cut-off of < 0.87 nmol/L (15.0% and 16.6%), with decreased readmission rates and no mortalities.

Conclusions

In patients presenting to the ED with a suspected infection, the blood biomarker MR-proADM could most accurately identify the likelihood of further disease progression. Incorporation into an early sepsis management protocol may therefore aid rapid decision-making in order to either initiate, escalate or intensify early treatment strategies, or identify patients suitable for safe out-patient treatment.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2329-5) contains supplementary material, which is available to authorized users.