Systemic Capillary Leak Syndrome Secondary to Coronavirus Disease 2019

SARS-CoV-2 spike protein induces the cytokine release syndrome by stimulating T cells to produce more IL-2

Introduction

Cytokine release syndrome (CRS) is one of the leading causes of mortality in patients with COVID-19 caused by the SARS-CoV-2 coronavirus. However, the mechanism of CRS induced by SARS-CoV-2 is vague.

Methods

Using spike protein combined with IL-2, IFN-γ, and TNF-α to stimulate human peripheral blood mononuclear cells (PBMCs) to secrete CRS-related cytokines, the content of cytokines in the supernatant was detected, and the effects of NK, T, and monocytes were analyzed.

Results

This study shows that dendritic cells loaded with spike protein of SARS-CoV-2 stimulate T cells to release much more interleukin-2 (IL-2,) which subsequently cooperates with spike protein to facilitate PBMCs to release IL-1β, IL-6, and IL-8. These effects are achieved via IL-2 stimulation of NK cells to release tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), as well as T cells to release IFN-γ Mechanistically, IFN-γ and TNF-α enhance the transcription of CD40, and the interaction of CD40 and its ligand stabilizes the membrane expression of toll-like receptor 4 (TLR4) that serves as a receptor of spike protein on the surface of monocytes. As a result, there is a constant interaction between spike protein and TLR4, leading to continuous activation of nuclear factor-κ-gene binding (NF-κB). Furthermore, TNF-α also activates NF-κB signaling in monocytes, which further cooperates with IFN-γ and spike protein to modulate NF-κB-dependent transcription of CRS-related inflammatory cytokines.

Discussion

Targeting TNF-α/IFN-γ in combination with TLR4 may represent a promising therapeutic approach for alleviating CRS in individuals with COVID-19.

Fatal Systemic Capillary Leak Syndrome in a Patient with a COVID-19 Infection

A 29-year-old Japanese woman was admitted to our hospital with a fever, cardiogenic shock, and cardiac arrest. Laboratory data indicated multiple organ failure in addition to hemoconcentration, hypoalbuminemia, and myocardial damage. The coronary angiography findings were normal, and fulminant myocarditis was suspected. Venoarterial peripheral extracorporeal membrane oxygenation and an Impella CP left ventricular assist device were initiated, along with the administration of positive inotropic agents. However, hypovolemic shock and hypoalbuminemia progressed along with severe anemia, and the patient died 18 hours after admission. The patient was diagnosed with systemic capillary leak syndrome associated with coronavirus disease 2019.

Capillary leak syndrome was associated with more severe multisystem inflammatory syndrome in children during the COVID-19 pandemic

AIM

This population-based study investigated the occurrence of capillary leak syndrome (CLS) in children with multisystem inflammatory syndrome in children (MIS-C), associated with COVID-19. We also examined associations between CLS and MIS-C disease severity.

METHODS

All eligible individuals aged 0-18 years, who were diagnosed with MIS-C in Skåne, southern Sweden, from 1 April 2020 to 31 July 2021, were studied. They were all included in the Pediatric Rheumatology Quality Register and clinical and laboratory data were compared between patients with and without CLS.

RESULTS

We included 31 patients (61% male) with MIS-C in the study. The median age at diagnosis was 10.6 years (range 1.99-17.15) and 45% developed CLS. All six patients who required intensive care had CLS. Patients with CLS also had a higher incidence of reduced cardiac function, measured as low ejection fraction. The CLS group exhibited significantly higher C-reactive protein values (p < 0.001) and N-terminal pro-B-type natriuretic peptide levels (p < 0.001), as well as lower platelet counts (p = 0.03), during the first week of treatment. Individuals with CLS also received more intense immunosuppression.

CONCLUSION

CLS was a common complication of MIS-C in our study and these patients had a more severe disease course that required more intensive treatment.

Two cases of systemic capillary leak syndrome associated with COVID-19 in Japan

Systemic Capillary Leak Syndrome (SCLS) is a rare disease that causes severe distributive shock provoked by infection or vaccination. SCLS is clinically diagnosed by a triad of distributive shock, paradoxical hemoconcentration, and hypoalbuminemia. SCLS associated with coronavirus disease (COVID-19) in adults has not been reported yet in Japan. Case 1: A 61-year-old woman with fever, sore throat, headache, and muscle pain was admitted to our emergency department with suspected COVID-19. She had been diagnosed with SCLS 3 years earlier. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen and polymerase chain reaction (PCR) tests were negative at admission. She went into shock in the emergency department and was treated for septic shock. The following day, the SARS-CoV-2 PCR test was positive. She did not respond to fluid resuscitation and catecholamine and finally died. Case 2: A 58-year-old man was admitted to our hospital for de-saturation due to COVID-19. He got into shock on day 3. SCLS was suspected, and 5 g of intravenous immunoglobulin and 5% albumin were administered for sepsis treatment. He responded to the aggressive fluid therapy within 48 h and was finally discharged. COVID-19 can trigger SCLS, and early recognition of SCLS is crucial for survival. Primary care physicians should consider SCLS when they observe distributive shock and paradoxical hemoconcentration deviations from the natural course of COVID-19.

Resuscitation-associated endotheliopathy (RAsE): a conceptual framework based on a systematic review and meta-analysis

INTRODUCTION

Shock-induced endotheliopathy (SHINE), defined as a profound sympathoadrenal hyperactivation in shock states leading to endothelial activation, glycocalyx damage, and eventual compromise of end-organ perfusion, was first described in 2017. The aggressive resuscitation therapies utilised in treating shock states could potentially lead to further worsening endothelial activation and end-organ dysfunction.

OBJECTIVE

This study aimed to systematically review the literature on resuscitation-associated and resuscitation-induced endotheliopathy.

METHODS

A predetermined structured search of literature published over an 11-year and 6-month period (1 January 2011 to 31 July 2023) was performed in two indexed databases (PubMed/MEDLINE and Embase) per PRISMA guidelines. Inclusion was restricted to original studies published in English (or with English translation) reporting on endothelial dysfunction in critically ill human subjects undergoing resuscitation interventions. Reviews or studies conducted in animals were excluded. Qualitative synthesis of studies meeting the inclusion criteria was performed. Studies reporting comparable biomarkers of endothelial dysfunction post-resuscitation were included in the quantitative meta-analysis.

RESULTS

Thirty-two studies met the inclusion criteria and were included in the final qualitative synthesis. Most of these studies (47%) reported on a combination of mediators released from endothelial cells and biomarkers of glycocalyx breakdown, while only 22% reported on microvascular flow changes. Only ten individual studies were included in the quantitative meta-analysis based on the comparability of the parameters assessed. Eight studies measured syndecan-1, with a heterogeneity index, I2 = 75.85% (pooled effect size, mean = 0.27; 95% CI - 0.07 to 0.60; p = 0.12). Thrombomodulin was measured in four comparable studies (I2 = 78.93%; mean = 0.41; 95% CI - 0.10 to 0.92; p = 0.12). Three studies measured E-selectin (I2 = 50.29%; mean =  - 0.15; 95% CI - 0.64 to 0.33; p = 0.53), and only two were comparable for the microvascular flow index, MFI (I2 = 0%; mean =  - 0.80; 95% CI - 1.35 to - 0.26; p < 0.01).

CONCLUSION

Resuscitation-associated endotheliopathy (RAsE) refers to worsening endothelial dysfunction resulting from acute resuscitative therapies administered in shock states. In the included studies, syndecan-1 had the highest frequency of assessment in the post-resuscitation period, and changes in concentrations showed a statistically significant effect of the resuscitation. There are inadequate data available in this area, and further research and standardisation of the ideal assessment and panel of biomarkers are urgently needed.

Pericardial effusion and systemic capillary leak syndrome late post-SARS-CoV-2 vaccination

We report an interesting case of pericardial effusion associated with idiopathic systemic capillary leak syndrome (ISCLS) following administration of SARS-CoV-2 vaccine. This patient initially presented with dyspnoea and chest pain, with non-pitting oedema and clear lung fields. The diagnosis of ISCLS was made based on the clinical syndrome and laboratory evidence of polycythaemia and hypoalbuminaemia. An enlarging pericardial effusion was diagnosed on transthoracic echocardiogram. Daily point-of-care ultrasound (POCUS)-guided volume management and serial transthoracic echocardiograms contributed to avoidance of refractory shock, cardiac tamponade and critical care admission.

Jerne's "immune network theory", of interacting anti-idiotypic antibodies applied to immune responses during COVID-19 infection and after COVID-19 vaccination

Niels Kaj Jerne has proposed the "immune network theory" of interactions among anti-idiotypic antibodies, able to interfere with humoral responses to certain antigens. After the occurrence of the primary generation of antibodies, against an antigenic epitope, idiotypes of these antibodies induce anti-idiotypic antibodies that modulate the intensity of the first response, and so on. Adverse effects following SARS-COV-2 COVID-19 vaccines are occasionally similar to the symptoms of COVID-19 infection. Rare events linked to SARS-CoV-2 vaccines also resemble some rarely reported COVID-19 complications. Safety data from product information by European Medicines Agency suggest that spectra do overlap for four main vaccines. The proposition is that vaccine events and COVID-19 complications are related to anti-idiotypic antibodies whose spatial shape can lead to interactions with ACE2 molecules, in individuals with a prolonged Spike protein synthesis. The vaccines target cells by their affinity to the vaccine vector, or to engulf lipid nanoparticles. Anti-idiotypic antibodies shaped similarly to the Spike protein possibly interact with ACE2 molecules and cause diverse signs and symptoms.

Systemic Capillary Leak Syndrome as a Rare, Potentially Fatal Complication of COVID-19: A Case Report and Literature Review

Systemic capillary leak syndrome (SCLS), also known as Clarkson's disease, is a rare and potentially lethal condition characterized by hypotension, hemoconcentration, and hypoalbuminemia; however, the cause of SCLS is still uncertain. We present the case of a 62-year-old male with flu-like symptoms who presented to the emergency department with shock. Initial evaluation revealed hemoconcentration, hypoalbuminemia, acute kidney failure, and positive polymerase chain reaction (PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Despite aggressive fluid resuscitation, the shock persisted, and the patient's condition deteriorated. After ruling out ischemia and septic shock, the patient was diagnosed with coronavirus disease 2019 (COVID-19)-associated SCLS. Treatment with remdesivir and intravenous immunoglobulin (IVIG), along with the restoration of intravascular volume, led to the gradual improvement of the patient's condition. The patient experienced pulmonary edema, which was managed by correcting the fluid balance through continuous hemodiafiltration. Eventually, the patient recovered without any residual organ complications. SCLS is often misdiagnosed because of its rarity and non-specific symptoms. Accurate diagnosis and understanding of the disease's pathophysiology are crucial for effective management. This report contributes to the existing literature by presenting a case of COVID-19-associated SCLS and emphasizes the need for further research on its occurrence and outcomes.

Compartment Syndrome of All Extremities in the Setting of COVID-19-Induced Systemic Capillary Leak Syndrome With Superimposed Myositis

Three years following the pandemic's emergence, COVID-19 has continued to affect much of the symptomatic population with widely varied respiratory complaints, fevers, numerous unexpected prodromal manifestations, and unknown long-term consequences. Scattered cases involving myopathies, rhabdomyolysis, and compartment syndrome have also been reported throughout the pandemic. Some similar cases have been attributed to systemic capillary leak syndrome (SCLS). Here, we report the development of compartment syndrome involving all extremities in a 57-year-old vaccinated female known to have COVID-19. In retrospect, we believe the clinical severity and the patient's sudden deterioration can also be attributed to the lesser-known SCLS. Treatment required fasciotomies of both forearms, arms, and legs. This is the most significantly involved case, leading to survival reported thus far. Lab abnormalities, misleading imaging, and symmetric involvement of all extremities posed a significant challenge to proper diagnosis and treatment. This case serves as a reminder for providers to remain cognizant of neurovascular emergencies during the workup of critically ill patients when the presentation is unrecognized and usual treatments are refractory. Its purpose is also to contribute to the global understanding of and response to COVID-19.

Systemic Capillary Leak Syndrome (SCLS) Presentation in Patients Receiving Anti-cancer Treatments

Systemic capillary leak syndrome (SCLS) is due to increased capillary permeability to proteins and fluid extravasation from blood vessels into surrounding tissues and body cavities. This fluid extravasation leads to hypotension, generalized anasarca, pleural effusions, and pericardial effusions -- the more severe cases of SCLS can cause multiorgan dysfunction, including cardiovascular collapse, shock, and death. The treatment includes corticosteroids, diuretics, albumin, immunoglobulins, and crystalloids. SCLS is potentially fatal. Recognizing signs and symptoms early and treating the patients is essential as this condition is fatal. It sometimes is a diagnosis of exclusion, being very challenging to diagnose and treat. The lack of understanding of the underlying mechanisms causing SCLS and proper treatment guidelines, especially in cancer patients, made diagnosing and treating this condition hard. Reports show that many cancers and anti-cancer treatments, including newer immunotherapy, cause SCLS. The mortality rate of SCLS associated with cytotoxic chemotherapy is 24% at five years. This review focuses on the cancers and anti-cancer drugs causing SCLS, treating acute SCLS, and available preventive regimens. The fundamental purpose of this review is to help clinicians recognize SCLS early to avoid delays in diagnosis and treatment. We also would like to elaborate on the fact that research on cancer-related SCLS is critical for developing staging criteria, useful diagnostic markers, prevention, and treatment strategies for anti-cancer drug-induced SCLS to prevent early discontinuation of anti-cancer drugs.

Idiopathic systemic capillary leak syndrome: a case report

BACKGROUND

Idiopathic systemic capillary leak syndrome (ISCLS) is a rare disease characterized by recurrent episodes of acute life-threatening attacks of shock, hemoconcentration, and hypoalbuminemia. Increase in capillary permeability results in reversible plasma movement into the interstitial spaces followed by appearance of related symptoms or complications, including renal failure. This condition can be potentially life-threatening; however, it is easily misdiagnosed.

CASE PRESENTATION

A 47-year-old man with no previous medical history presented to the emergency department after experiencing general weakness and abdominal pain. He developed hypovolemic shock within 3 h of presentation and initial laboratory tests showed hemoconcentration, hypoalbuminemia and acute kidney injury. Following vigorous fluid therapy and supportive care, the patient recovered, but a similar episode recurred after 4 months without any specific trigger. Based on the combined clinical manifestations and laboratory findings of both the attacks, he was diagnosed with ISCLS. Symptomatic relief was achieved via oxygen supplementation and massive volume replacement using normal saline and the patient was prescribed bambuterol 10 mg and theophylline 400 mg once-a-day. He was discharged from the hospital on day 5 of hospitalization. Thereafter, the patient has been followed for 5 years without any symptoms or recurrence of ISCLS even in the situation of COVID-19 infection.

CONCLUSIONS

ISCLS is an extremely infrequent and commonly misdiagnosed disease. However, early diagnosis, treatment and prophylaxis through accumulated clinical data can prevent ISCLS recurrence and the development of related fatal complications. Therefore, clinicians need to be well aware of the variety of clinical characteristics and treatment options of this disease.

Intravenous Immunoglobulins Tapering and Withdrawal in Systemic Capillary Leak Syndrome (Clarkson Disease)

BACKGROUND

The systemic capillary leak syndrome (SCLS), also known as Clarkson disease, is a very rare condition characterized by recurrent life-threatening episodes of vascular hyperpermeability in the presence of a monoclonal gammopathy. Extended intravenous immunoglobulin (IVIG) treatment is associated with fewer recurrences and improved survival, but the optimal treatment dosage and duration remain unknown.

OBJECTIVE

We aim to evaluate the safety of IVIG tapering and withdrawal in patients with SCLS.

METHODS

We conducted a retrospective multicenter study including all adult patients with monoclonal gammopathy-associated SCLS from the EurêClark registry who received at least 1 course of IVIG. The primary end point was overall survival according to IVIG withdrawal.

RESULTS

Fifty-nine patients of mean ± SD age 51 ± 13 years were included. Overall cumulative probabilities of 2-, 5-, 10- and 15-year survival were 100%, 85%, 72%, 44%, respectively. The IVIG was withdrawn at least once in 18 patients (31%; W+ group) and never in 41 patients (69%; W- group). Cumulative probabilities of 10-year survival in W+ versus W- groups were 50% and 83% (log rank test, P = .02), respectively. Relapse rate and the median number of relapses in the W+ versus the W- groups were 72% versus 58% (P = 0.3) and 2.5 (0.3-4) versus 1 (0-2) (P = .03), respectively. The IVIG tapering was not statistically associated with increased person-year incidence of attacks using a mixed linear model.

CONCLUSIONS

The IVIG withdrawal was associated with increased mortality and higher rate of recurrence in SCLS patients. The IVIG tapering might be cautiously considered in stable SCLS patients.

Do we miss rare adverse events induced by COVID-19 vaccination?

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has caused many complications, the invention of coronavirus disease 2019 (COVID-19) vaccines has also brought about several adverse events, from common side effects to unexpected and rare ones. Common vaccine-related adverse reactions manifest locally or systematically following any vaccine, including COVID-19 vaccines. Specific side effects, known as adverse events of particular interest (AESI), are unusual and need more evaluation. Here, we discuss some of the most critical rare adverse events of COVID-19 vaccines.

COVID-19, Endothelium and the Cardiometabolic Patient: A Possible Role for Capillary Leak Syndrome

Capillary leak syndrome is an under-diagnosed condition leading to serious hypoalbuminemia with diffuse edema, pulmonary edema, severe hypotension, and possibly death. Sepsis leading to hemophagocytic lymphohistiocytosis (HLH) is a major risk factor; however, capillary hyper-permeability is the core underlying pathophysiological mechanism. Endothelial dysfunction plays a major role in cardiometabolic disease through insulin resistance, lipotoxicity, and, eventually, oxidative stress and chronic inflammation. We review the literature concerning the aforementioned mechanisms as well-established risk factors for adverse COVID-19 outcomes. We especially focus on data regarding the underlying endothelial effects of SARS-CoV-2 infection, including direct damage and increased vascular leakage through a hyper-inflammatory cascade and diminished nitric oxide bioavailability. Interestingly, an increased incidence of hypoalbuminemia has been observed in patients with severe COVID-19, especially those with underlying cardiometabolic disease. Importantly, low albumin levels present a strong, positive association with poor disease outcomes. Therefore, in this review article, we highlight the important role of cardiovascular risk factors on endothelium integrity and the possible link of endothelial damage in the hypoalbuminemia-associated adverse prognosis of COVID-19 patients.

An unusual presentation of recurrent COVID-19 associated systemic capillary leak syndrome in a patient with multi-system inflammatory syndrome in adults (MIS-A) due to prior COVID-19 infection: Case report and literature review

Introduction

and importance: Systemic capillary leak syndrome (SCLS) and multisystem inflammatory syndrome in adults (MIS-A) are very rare multifactorial etiology disorders associated with COVID-19 infection. Both conditions are thought to be manifested by the inflammatory state induced by COVID-19 infection. Recurrent COVID-19-associated concomitant/successive manifestations of both disorders have not been reported yet.

Case presentation

We report a 38-year-old Asian gentleman who presented initially with fever, cough, shortness of breath, body aches, dizziness, and epigastric pain due to COVID-19 infection. A few days before this presentation, the same patient developed multisystem inflammatory syndrome in adults (MIS-A). Later, based on clinical and laboratory investigations, he was diagnosed with new-onset systemic capillary leak syndrome (SCLS). Despite resuscitative measures, the patient passed away.

Clinical discussion

The increased risk of inflammatory complications associated with COVID-19 infection is an emerging concern. Our case report signifies the importance of COVID-19 awareness in less educated and underserved areas with fewer information resources. Rare and fatal manifestations should also be advertised and discussed with the general masses with equal emphasis.

Conclusion

This case signifies the importance of understanding the pathophysiology of new-onset systemic capillary leak syndrome in a patient with recurrent COVID-19 infection and utilizing clinical knowledge and decision-making to manage such rare and complex disorders.

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Systemic capillary leak syndrome (SCLS) is a very rare disorder of multifactorial etiology which manifests as a cluster of fatal symptoms like hypotension, edema, hemoconcentration, and shock.

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Systemic capillary leak syndrome (SCLS) and multisystem inflammatory syndrome in adults (MIS-A) are very rare multifactorial etiology disorders associated with COVID-19 infection.

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This case signifies the importance of understanding the pathophysiology of new-onset systemic capillary leak syndrome in a patient with recurrent COVID-19 infection and utilizing clinical knowledge and decision-making to manage such rare and complex disorders.

Limb Fasciotomy for COVID-19 Patients: Is the Chance to Cut a Chance to Cure?

Based on the findings of two consecutive cases of upper extremity compartment syndrome encountered at our institution, we hypothesize that the presence of compartment syndrome in the unstable COVID-19 patient may be associated with high mortality and low limb salvage rates. A literature search was conducted with key search terms, including “compartment syndrome, fasciotomy, COVID, and coronavirus.” Articles describing patients with a confirmed COVID-19 diagnosis who developed extremity compartment syndrome were included in our study. The primary outcome investigated was patient survival. Secondary outcomes included limb survival and limb salvage. Limb salvage was calculated in patients who survived to time of discharge, whereas limb survival was counted for all patients. We then added our two cases to the findings reported in our literature to determine current overall limb salvage and patient survival rates. Our review of the literature yielded six case reports of ten extremities that developed compartment syndrome in the COVID-19 positive patient. Overall survival was four of six patients (67%). The overall limb survival rate at the time of hospital discharge was three of 10 (30%). With the addition of our two cases, overall survival was four of eight (50%) and overall limb survival rate was three of 12 (25%). Furthermore, with inclusion of our two cases, the patient survival rate of hemodynamically unstable patients was only three of seven (43%). The development of compartment syndrome in the unstable COVID-19 patient may be a harbinger of death, and the decision to proceed with operative intervention is challenging, complex, and in some cases must prioritize life over limb.

Bilateral Lower Extremity Compartment Syndrome Secondary to COVID-19 Myositis in a Young Vaccinated Woman

Coronavirus disease 2019 (COVID-19) typically manifests with respiratory symptoms and can ultimately progress to severe multiorgan failure. Viral myositis, systemic capillary leak syndrome, and arteriovenous thrombosis are atypical manifestations of COVID-19. We present a case of a 33-year-old woman, fully vaccinated against COVID-19, who developed myositis and shock. She ultimately required bilateral lower extremity fasciotomies secondary to compartment syndrome, presumably from COVID-19 myositis. Although compartment syndrome from COVID-19 myositis has been reported for ocular, hand, and thigh compartment syndromes, this is the first case report showing bilateral lower extremity compartment syndrome secondary to COVID-19 myositis in a fully vaccinated individual. As we learn more about COVID-19 and its extrapulmonary effects, it is imperative to consider all working diagnoses when working up patients. Providers must be aware of extrapulmonary effects of COVID-19, particularly in individuals who might deviate from traditional symptoms.

Detailed videocapillaroscopic microvascular changes detectable in adult COVID-19 survivors

Objective

COVID-19 is a multisystem disease that causes endothelial dysfunction and organ damage. Aim of the study was to evaluate the microvascular status in COVID-19 survivors with past different disease severity, in comparison with age and sex-matched primary Raynaud's phenomenon (PRP) patients and control subjects (CNT), including possible effects of concomitant therapies.

Methods

Sixty-one COVID-19 survivors (mean age 58 ± 13 years, mean days from disease onset 126 ± 53 and mean days from recovery 104 ± 53), thirty-one PRP patients (mean age 59 ± 15 years, mean disease duration 11 ± 10 years) and thirty CNT (mean age 58 ± 13 years) underwent nailfold videocapillaroscopy (NVC) examination. The following capillaroscopic parameters were searched and scored (0–3): dilated capillaries, giant capillaries, isolated microhemorrhages, capillary ramifications (angiogenesis) and capillary number, including absolute capillary number per linear millimeter at the nailfold bed.

Results

The mean nailfold capillary number per linear millimeter was significantly lower in COVID-19 survivors when compared with PRP patients and CNT (univariate and multivariate analysis p < 0.001). On the contrary, COVID-19 survivors showed significantly less isolated microhemorrhages than PRP patients and CNT (univariate and multivariate analysis, p = 0.005 and p = 0.012, respectively). No statistically significant difference was observed between COVID-19 survivors and control groups concerning the frequency of dilated capillaries and capillary ramifications. COVID-19 selective therapies showed a promising trend on preserving capillary loss and deserving further investigations.

Conclusions

SARS-CoV-2 seems to mainly induce a significant loss of capillaries in COVID-19 survivors at detailed NVC analysis in comparison to controls. The presence of a significant reduced score for isolated microhaemorrhages in COVID-19 survivors deserves further analysis.

Cerebrospinal fluid findings in COVID-19: a multicenter study of 150 lumbar punctures in 127 patients

BACKGROUND

Comprehensive data on the cerebrospinal fluid (CSF) profile in patients with COVID-19 and neurological involvement from large-scale multicenter studies are missing so far.

OBJECTIVE

To analyze systematically the CSF profile in COVID-19.

METHODS

Retrospective analysis of 150 lumbar punctures in 127 patients with PCR-proven COVID-19 and neurological symptoms seen at 17 European university centers RESULTS: The most frequent pathological finding was blood-CSF barrier (BCB) dysfunction (median QAlb 11.4 [6.72-50.8]), which was present in 58/116 (50%) samples from patients without pre-/coexisting CNS diseases (group I). QAlb remained elevated > 14d (47.6%) and even > 30d (55.6%) after neurological onset. CSF total protein was elevated in 54/118 (45.8%) samples (median 65.35 mg/dl [45.3-240.4]) and strongly correlated with QAlb. The CSF white cell count (WCC) was increased in 14/128 (11%) samples (mostly lympho-monocytic; median 10 cells/µl, > 100 in only 4). An albuminocytological dissociation (ACD) was found in 43/115 (37.4%) samples. CSF L-lactate was increased in 26/109 (24%; median 3.04 mmol/l [2.2-4]). CSF-IgG was elevated in 50/100 (50%), but was of peripheral origin, since QIgG was normal in almost all cases, as were QIgA and QIgM. In 58/103 samples (56%) pattern 4 oligoclonal bands (OCB) compatible with systemic inflammation were present, while CSF-restricted OCB were found in only 2/103 (1.9%). SARS-CoV-2-CSF-PCR was negative in 76/76 samples. Routine CSF findings were normal in 35%. Cytokine levels were frequently elevated in the CSF (often associated with BCB dysfunction) and serum, partly remaining positive at high levels for weeks/months (939 tests). Of note, a positive SARS-CoV-2-IgG-antibody index (AI) was found in 2/19 (10.5%) patients which was associated with unusually high WCC in both of them and a strongly increased interleukin-6 (IL-6) index in one (not tested in the other). Anti-neuronal/anti-glial autoantibodies were mostly absent in the CSF and serum (1509 tests). In samples from patients with pre-/coexisting CNS disorders (group II [N = 19]; including multiple sclerosis, JC-virus-associated immune reconstitution inflammatory syndrome, HSV/VZV encephalitis/meningitis, CNS lymphoma, anti-Yo syndrome, subarachnoid hemorrhage), CSF findings were mostly representative of the respective disease.

CONCLUSIONS

The CSF profile in COVID-19 with neurological symptoms is mainly characterized by BCB disruption in the absence of intrathecal inflammation, compatible with cerebrospinal endotheliopathy. Persistent BCB dysfunction and elevated cytokine levels may contribute to both acute symptoms and 'long COVID'. Direct infection of the CNS with SARS-CoV-2, if occurring at all, seems to be rare. Broad differential diagnostic considerations are recommended to avoid misinterpretation of treatable coexisting neurological disorders as complications of COVID-19.

Veno-venous-extracorporeal membrane oxygenation treatment for severe capillary leakage syndrome: A case report

BACKGROUND

Capillary leak syndrome (CLS) is characterized by the leakage of large amounts of fluid and plasma proteins into the interstitial space, resulting in hypoalbuminemia, hypovolemic shock, elevated blood concentration, systemic progressive edema, and multiple serosal cavity effusion. Clinical syndromes such as cavity effusion pose a grave threat to the life and health of the patient.

CASE SUMMARY

A 58-year-old female patient was admitted to the hospital after being in a coma for 6 h following accidental ingestion of a pesticide. She was treated with phencyclidine hydrochloride and pralidoxime iodide for detoxification, mechanical ventilation to maintain oxygen supply, continuous renal replacement therapy to maintain the internal environment, and hemoperfusion to promote the excretion of toxins. She also received a transfusion of red blood cells and massive fluid resuscitation. However, her blood pressure was not maintained. The patient was diagnosed with CLS due to pesticide poisoning. Oxygenation was difficult to maintain under full ventilator support; therefore, veno-venous-extracorporeal membrane oxygenation (VV-ECMO) treatment was given 13 h after admission. Her oxygenation level improved, but a large amount of ascites and pleural effusion soon became apparent. We continued drainage with an indwelling drainage tube, and the ECMO flow stabilized. The leakage gradually decreased, and ECMO was discontinued 3 d later. On the 6^th day, the patient recovered from unconsciousness, but on gastroscopic evaluation, severe erosions were found in her entire stomach. With the family’s consent, treatment was stopped, and the patient was discharged from the hospital on the 7^th day.

CONCLUSION

ECMO, liquid resuscitation and management, and improvement in plasma colloidal osmotic pressure, circulation, and tissue oxygen supply are crucial in treating CLS.

New-Onset Systemic Capillary Leak Syndrome in an Adult Patient with COVID-19

Systemic capillary leak syndrome (SCLS) is a rare disorder manifesting as shock, hemoconcentration, and hypoalbuminemia, which may be either idiopathic or secondary to an underlying disease process. We report a case of an adult with COVID-19 infection associated with new onset SCLS. Our case joins only two other cases of new SCLS associated with COVID-19 infection reported in the literature. The clinical and laboratory findings in this case are distinct from findings seen in COVID-19 cytokine storm syndrome. Whether our therapeutic approach was efficacious is unknown. Further research into causes and therapies for these syndromes is urgently indicated.

Acute tubulointerstitial nephritis and COVID-19

Coronavirus disease 2019 (COVID-19) is an ongoing pandemic that to date has spread to >100 countries. Acute kidney injury is not uncommon with this disease. The most common kidney biopsy finding is acute tubular injury. Glomerular diseases such as collapsing glomerulopathy and vasculitis, and thrombotic microangiopathy have been reported. Viral inclusion particles with distinctive spikes in the tubular epithelium and podocytes, and endothelial cells of the glomerular capillary loops, have been visualized by electron microscopy by some but disputed by others as non-viral structures. Interstitial infiltrates have not commonly been described in the published kidney biopsy series from patients with COVID-19. Medications used to treat COVID-19 can lead to interstitial nephritis, but very few have been reported. In summary, interstitial kidney disease is a rare finding in COVID-19.

[SARS-CoV-2 vaccines and reaction of the immune system. Can the epidemic spread of the virus be prevented by vaccination?]

Since the end of 2019 a new coronavirus, SARS-CoV-2, first identified in Wuhan, China, is spreading around the world partially associated with a high death toll. Besides hygienic measurements to reduce the spread of the virus vaccines have been confected, partially based on the experiences with Ebola virus vaccine, based on recombinant human or chimpanzee adenovirus carrying the spike protein and its ACE2 receptor binding domain (RBD). Further vaccines are constructed by spike protein coding mRNA incorporated in lipid nano vesicles that after entry in human cells produce spike protein. Both vaccine types induce a strong immune response that lasts for months possibly for T-cell immunity a few years. Due to mutations in the coronavirus genome in several parts of the world variants selected, that were partially more pathogenic and partially easier transmissible - variants of concern (VOC). Until now vaccinees are protected against the VOC, even when protection might be reduced compared to the Wuhan wild virus.An open field is still how long the vaccine induced immunity will be sufficient to prevent infection and/or disease; and how long the time period will last until revaccination will be required for life saving protection, whether a third vaccination is needed, and whether revaccination with an adenovirus-based vaccine will be tolerated.

Fatal Exacerbations of Systemic Capillary Leak Syndrome Complicating Coronavirus Disease

We report 2 fatal exacerbations of systemic capillary leak syndrome (SCLS), also known as Clarkson disease, associated with coronavirus disease (COVID-19) in the United States. One patient carried an established diagnosis of SCLS and the other sought treatment for new-onset hypotensive shock, hemoconcentration, and anasarca, classic symptoms indicative of an SCLS flare. Both patients had only mild-to-moderate symptoms of COVID-19. This clinical picture suggests that these patients succumbed to complications of SCLS induced by infection with severe acute respiratory syndrome coronavirus 2. Persons with known or suspected SCLS may be at increased risk for developing a disease flare in the setting of mild-to-moderate COVID-19 infection.

Systemic Capillary Leak Syndrome triggered by SARS-CoV2 infection: Case Report and Systematic Review

Objective: Systemic capillary leak syndrome (SCLS) is a severe condition characterized by the coexistence of hypovolaemic shock, haemococentration, and hypoalbuminaemia, without albuminuria, that may progress to multiorgan failure and an unfavourable outcome. Its development is often triggered by viral infections, such as influenza A virus, but it is unclear whether it is also triggered by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We aimed to investigated the association between SARS-CoV-2 and SCLS.Method: We present the case of a 55-year-old-woman affected by SARS-CoV-2 infection who developed SCLS. Moreover, we performed a systematic review of the literature to identify any common features with other cases and to describe clinical characteristics and outcomes.Results: We found three other cases of SCLS occurring during SARS-CoV-2 infection in 2020. Taking all cases together, the mean age was 50 years (range 38-63), with a 1:1 gender ratio. Respiratory manifestations were the most common symptom, and all patients required admission to the intensive care unit. The mortality rate was 50%.Conclusions: SARS-CoV-2 infection may trigger SCLS disease, either by an overproduction of proinflammatory cytokines or by direct viral infection of the endothelium. Since SCLS may have a poor prognosis, in every SARS-CoV-2-infected patient presenting the suggestive triad of hypovolaemic shock, haemoconcentration, and hypoproteinaemia, an SCLS diagnosis should be considered and early treatment initiated.

Endothelial Dysfunction in Atherosclerotic Cardiovascular Diseases and Beyond: From Mechanism to Pharmacotherapies

The endothelium, a cellular monolayer lining the blood vessel wall, plays a critical role in maintaining multiorgan health and homeostasis. Endothelial functions in health include dynamic maintenance of vascular tone, angiogenesis, hemostasis, and the provision of an antioxidant, anti-inflammatory, and antithrombotic interface. Dysfunction of the vascular endothelium presents with impaired endothelium-dependent vasodilation, heightened oxidative stress, chronic inflammation, leukocyte adhesion and hyperpermeability, and endothelial cell senescence. Recent studies have implicated altered endothelial cell metabolism and endothelial-to-mesenchymal transition as new features of endothelial dysfunction. Endothelial dysfunction is regarded as a hallmark of many diverse human panvascular diseases, including atherosclerosis, hypertension, and diabetes. Endothelial dysfunction has also been implicated in severe coronavirus disease 2019. Many clinically used pharmacotherapies, ranging from traditional lipid-lowering drugs, antihypertensive drugs, and antidiabetic drugs to proprotein convertase subtilisin/kexin type 9 inhibitors and interleukin 1β monoclonal antibodies, counter endothelial dysfunction as part of their clinical benefits. The regulation of endothelial dysfunction by noncoding RNAs has provided novel insights into these newly described regulators of endothelial dysfunction, thus yielding potential new therapeutic approaches. Altogether, a better understanding of the versatile (dys)functions of endothelial cells will not only deepen our comprehension of human diseases but also accelerate effective therapeutic drug discovery. In this review, we provide a timely overview of the multiple layers of endothelial function, describe the consequences and mechanisms of endothelial dysfunction, and identify pathways to effective targeted therapies. SIGNIFICANCE STATEMENT: The endothelium was initially considered to be a semipermeable biomechanical barrier and gatekeeper of vascular health. In recent decades, a deepened understanding of the biological functions of the endothelium has led to its recognition as a ubiquitous tissue regulating vascular tone, cell behavior, innate immunity, cell-cell interactions, and cell metabolism in the vessel wall. Endothelial dysfunction is the hallmark of cardiovascular, metabolic, and emerging infectious diseases. Pharmacotherapies targeting endothelial dysfunction have potential for treatment of cardiovascular and many other diseases.

Capillary-leak syndrome: an unrecognized early immune adverse effect of checkpoint-inhibitors treatment

Capillary-leak syndrome is strongly associated with cytokine activity states. It is an ill-recognized adverse effect of checkpoint inhibitors treatment, which are typically associated with cellular immune response. We describe two patients with capillary leak syndrome following immune checkpoint inhibitors treatment. We present linking mechanisms between checkpoint inhibitors, cellular immunity, cytokine action and endothelial damage. We suggest that capillary-leak syndrome is a unique adverse effect of immunotherapy, resulting from complex interactions between cellular and cytokine activation and that its expression is probably depending on inherent host immune variabilities.

Proteomic characteristics of bronchoalveolar lavage fluid in critical COVID-19 patients

Up to 10-20% of patients with coronavirus disease 2019 (COVID-19) develop a severe pulmonary disease due to immune dysfunction and cytokine dysregulation. However, the extracellular proteomic characteristics in respiratory tract of these critical COVID-19 patients still remain to be investigated. In the present study, we performed a quantitative proteomic analysis of the bronchoalveolar lavage fluid (BALF) from patients with critical COVID-19 and from non-COVID-19 controls. Our study identified 358 differentially expressed BALF proteins (P < 0.05), among which 41 were significantly changed after using the Benjamini-Hochberg correction (q < 0.05). The up-regulated signaling was found to be mainly involved in inflammatory signaling and response to oxidative stress. A series of increased extracellular factors including Tenascin-C (TNC), Mucin-1 (KL-6 or MUC1), Lipocalin-2 (LCN2), periostin (POSTN), Chitinase 3-like 1 (CHI3L1 or YKL40), and S100A12, and the antigens including lymphocyte antigen 6D/E48 antigen (LY6D), CD9 antigen, CD177 antigen, and prostate stem cell antigen (PSCA) were identified, among which the proinflammatory factors TNC and KL-6 were further validated in serum of another thirty-nine COVID-19 patients and healthy controls, showing high potentials of being biomarkers or therapeutic candidates for COVID-19. This BALF proteome associated with COVID-19 would also be a valuable resource for researches on anti-inflammatory medication and understanding the molecular mechanisms of host response. DATABASE: Proteomic raw data are available in ProteomeXchange (http://proteomecentral.proteomexchange.org) under the accession number PXD022085, and in iProX (www.iprox.org) under the accession number IPX0002429000.