Capillary leak syndrome: State of the art in 2021

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.

Approach to Idiopathic Anaphylaxis in Adolescents

Anaphylaxis is a potentially-life threatening condition. Adolescents are particularly vulnerable due to increased risk-taking behaviors, poor disease management, and minimized perception of risk. Although most anaphylaxis can be attributed to food, drug, or venom allergy via a detailed history and confirmatory studies, in nearly 1 in 5 cases, the cause may not be obvious. Clinical differentials including rare allergens, cofactors, mast-cell disorders, and mimic disorders can increase the likelihood of discovering of the cause of anaphylaxis.

Capillary leak and endothelial permeability in critically ill patients: a current overview

Capillary leak syndrome (CLS) represents a phenotype of increased fluid extravasation, resulting in intravascular hypovolemia, extravascular edema formation and ultimately hypoperfusion. While endothelial permeability is an evolutionary preserved physiological process needed to sustain life, excessive fluid leak-often caused by systemic inflammation-can have detrimental effects on patients' outcomes. This article delves into the current understanding of CLS pathophysiology, diagnosis and potential treatments. Systemic inflammation leading to a compromise of endothelial cell interactions through various signaling cues (e.g., the angiopoietin-Tie2 pathway), and shedding of the glycocalyx collectively contribute to the manifestation of CLS. Capillary permeability subsequently leads to the seepage of protein-rich fluid into the interstitial space. Recent insights into the importance of the sub-glycocalyx space and preserving lymphatic flow are highlighted for an in-depth understanding. While no established diagnostic criteria exist and CLS is frequently diagnosed by clinical characteristics only, we highlight more objective serological and (non)-invasive measurements that hint towards a CLS phenotype. While currently available treatment options are limited, we further review understanding of fluid resuscitation and experimental approaches to target endothelial permeability. Despite the improved understanding of CLS pathophysiology, efforts are needed to develop uniform diagnostic criteria, associate clinical consequences to these criteria, and delineate treatment options.

Idiopathic Systemic Capillary Leak Syndrome: A Clinical Case

Idiopathic systemic capillary leak syndrome (ISCLS) is a rare condition caused by the extravasation of intravascular fluids and proteins into the interstitial space due to increased vascular endothelium permeability. It is characterized by episodes of hypotension, hypoalbuminemia, and hemoconcentration with generalized edema. Its etiopathogenesis is unknown. However, it is associated with monoclonal gammopathy in more than 80% of cases. There is currently no targeted treatment, and the approach during a crisis is supportive, mainly to control blood pressure, maintain perfusion of vital organs, and prevent complications, such as acute pulmonary edema and organ failure due to ischemia, which are the primary causes of death. We present the case of a 72-year-old man with generalized edema and pleural, pericardial, and peritoneal effusions whose laboratory results showed hypoalbuminemia, hypoproteinemia, and immunoglobulin G kappa monoclonal gammopathy. Other etiologies for severe hypoalbuminemia with anasarca were excluded after an exhaustive complementary study, leading to the diagnosis of ISCLS associated with monoclonal gammopathy. The patient showed progressive clinical improvement with albumin and diuretic therapy. However, they were readmitted to the hospital due to hypotension with multiorgan dysfunction and died a few hours later.

Hypovolemia with peripheral edema: What is wrong?

Fluid normally exchanges freely between the plasma and interstitial space and is returned primarily via the lymphatic system. This balance can be disturbed by diseases and medications. In inflammatory disease states, such as sepsis, the return flow of fluid from the interstitial space to the plasma seems to be very slow, which promotes the well-known triad of hypovolemia, hypoalbuminemia, and peripheral edema. Similarly, general anesthesia, for example, even without mechanical ventilation, increases accumulation of infused crystalloid fluid in a slowly equilibrating fraction of the extravascular compartment. Herein, we have combined data from fluid kinetic trials with previously unconnected mechanisms of inflammation, interstitial fluid physiology and lymphatic pathology to synthesize a novel explanation for common and clinically relevant examples of circulatory dysregulation. Experimental studies suggest that two key mechanisms contribute to the combination of hypovolemia, hypoalbuminemia and edema; (1) acute lowering of the interstitial pressure by inflammatory mediators such as TNFα, IL-1β, and IL-6 and, (2) nitric oxide-induced inhibition of intrinsic lymphatic pumping.

Nivolumab-induced capillary leak syndrome associated with chylothorax in a melanoma patient: A case report and review of the literature

Introduction

Adverse events (AEs) of immune checkpoint inhibitors (ICIs) are frequent and mainly due to an overactivity of the immune system leading to excessive inflammatory responses (immune-related AE) that can affect any organ of the body. Beside the most frequent AEs, there are rare AEs whose diagnosis and treatment can be challenging. We report here a singular case of capillary leak syndrome (CLS) associated with chylothorax occurring in a patient who has been treated with adjuvant nivolumab (anti-PD1) for resected AJCC stage IIB primary melanoma.

Case presentation

A 43-year-old woman was diagnosed with a nodular stage IIB melanoma of her left thigh, according to the AJCC 8th edition (T3bN0M0). The woman was treated with adjuvant nivolumab. She stopped the treatment after 4 infusions due to thrombopenia. Three months later, she developed facial and leg edema and ascites due to capillary leak syndrome. The CLS was associated with chylothorax and elevated vascular endothelial growth factor. The patient was initially treated with several pleural puncturing and steroids. CLS and chylothorax progressively decreased with intravenous immunoglobulins and fat-free diet without recurrence of melanoma at one-year follow-up.

Conclusion

CLS is a rare and potentially life-threatening AE of ICIs such as anti-PD1. This AE may be associated with chylothorax probably related to lymphatic permeability induced by anti-PD1.

Rapid Progression of COVID-19-Associated Fatal Capillary Leak Syndrome

Several cases of capillary leak syndrome (CLS) related to COVID-19 or vaccination against SARS-CoV-2 have been described in the literature. We present a case of a 42-year-old, previously healthy male, presenting with a mild form of COVID-19, who suddenly developed severe shock with hypotension and severe hemoconcentration within hours of admission to the hospital. Volume resuscitation was not effective, increasing hemoglobin (198 g/L on admission, 222 g/L 9 h later) suggested fluid leak into peripheral tissues. After cardiac arrest, the patient was resuscitated and connected to extracorporeal membrane oxygenation, but died shortly afterwards due to refractory heart failure. Retrospective investigation of blood samples confirmed diagnosis of CLS by progressive hypoalbuminemia (40 g/L on admission, 14 g/L 19 h later) and monoclonal gammopathy kappa (4.7 g/L). Patient's CLS was triggered by COVID-19, either a first attack of idiopathic CLS called Clarkson's disease or a COVID-19-induced secondary CLS.

Capillary leak syndrome following COVID-19 vaccination: Data from the European pharmacovigilance database Eudravigilance

Capillary leak syndrome (CLS) emerged as new adverse event after immunization (AEFI) associated to COVID-19 vaccination. CLS is a rare condition characterized by increased capillary permeability, resulting in hypoalbuminemia, hypotension, and edema mainly in the upper and lower limbs. Our pharmacovigilance study aims to evaluate the CLS onset following receipt of COVID-19 mRNA vaccines (mRNA-1273 and BNT162b2) compared to viral vector vaccines (Ad26.COV2-S and ChAdOx1-SARS-COV-2). We carried a cross-sectional study using all Individual Case Safety Reports (ICSRs) reporting a COVID-19 vaccine as suspected drug and CLS as AEFI, which were collected in the pharmacovigilance database EudraVigilance from January 1st, 2021, to January 14th, 2022. We applied the Reporting Odds Ratio (ROR) 95% CI for the disproportionality analysis. During our study period, CLS was described as AEFI in 84 out of 1,357,962 ICRs reporting a vaccine COVID-19 as suspected drug and collected in the EV database. Overall, the ICSR reported by CLS were mainly related to the viral vector COVID-19(ChAdOx1-SARS-COV-2 = 36; Ad26.COV2-S = 9). The mRNA COVID-19 vaccines were reported in 39 ICSRs (BNT162b2 =33; mRNA-1273 =6). Majority of ICSRs were reported by healthcare professionals (71.4%). Majority of the patients were adult (58.3%) and the female gender accounted in more than 65% of ICSRs referred both to classes vaccines. In particular, women were more represented in ICSRs referred to mRNA-1273 (83.3%) and to ChAdOx1-SARS-COV-2 (72.2%). The CLS outcome was more frequently favorable in mRNA ICSRs (33,3%) than the viral vector ones (13.3%). Among the ICSRs reporting CLS with unfavorable outcome, we found also 9 fatal cases (BNT162b2 = 1; ChAdOx1-SARS-COV-2 = 4; Ad26.COV2-S = 4). From disproportionality analysis emerged a lower CLS reporting probability after vaccination with mRNA vaccines compared to viral vector-based ones (ROR 0.5, 95% CI 0.3–0.7; p &lt;0.001).Our findings, even if subject to the limitations of spontaneous reporting systems, suggest a small but statistically significant safety concern for CLS following receipt of COVID-19 viral vector vaccines, in particular with Ad26.COV2-S. Cytokine-release following T-cell activation could be involved in CLS occurrence, but a precise mechanism has been not yet identified. COVID-19 vaccines remain attentive as possible triggers of CLS.

Massive vulvar edema revealing idiopathic systemic capillary leak syndrome

Idiopathic systemic capillary leak syndrome is a rare disease characterized by recurrent episodes of hypotension, hypoalbuminemia and peripheral edema caused by capillary hyperpermeability with approximately 350 documented cases worldwide. We report herein the case of a 22-year-old primiparous patient with an unusual compartment syndrome represented with spontaneous massive vulvar edema. Treatment consisted of volume replacement and intravenous polyvalent immunoglobulins perfusions. Vulvar edema was treated surgically by incision and drainage with favorable outcome. The pregnancy follow-up did not show any fetal abnormalities. The childbirth at 35 weeks was natural and the newborn was healthy.

Comparison of Piperacillin and Tazobactam Pharmacokinetics in Critically Ill Patients with Trauma or with Burn

Critical illness caused by burn and sepsis is associated with pathophysiologic changes that may result in the alteration of pharmacokinetics (PK) of antibiotics. However, it is unclear if one mechanism of critical illness alters PK more significantly than another. We developed a population PK model for piperacillin and tazobactam (pip-tazo) using data from 19 critically ill patients (14 non-burn trauma and 5 burn) treated in the Military Health System. A two-compartment model best described pip-tazo data. There were no significant differences found in the volume of distribution or clearance of pip-tazo in burn and non-burn patients. Although exploratory in nature, our data suggest that after accounting for creatinine clearance (CrCl), doses would not need to be increased for burn patients compared to trauma patients on consideration of PK alone. However, there is a high reported incidence of augmented renal clearance (ARC) in burn patients and pharmacodynamic (PD) considerations may lead clinicians to choose higher doses. For critically ill patients with normal kidney function, continuous infusions of 13.5-18 g pip-tazo per day are preferable. If ARC is suspected or the most stringent PD targets are desired, then continuous infusions of 31.5 g pip-tazo or higher may be required. This approach may be reasonable provided that therapeutic drug monitoring is enacted to ensure pip-tazo levels are not supra-therapeutic.

A Case of Systemic Capillary Leak Syndrome with Severe Cardiac Dysfunction after mRNA Vaccination for COVID-19

A 53-year-old woman with no significant medical history developed cardiogenic shock 4 days after receiving the second dose of the COVID-19 mRNA vaccine (BNT162b2, Pfizer/BioNtech). The patient required extracorporeal membrane oxygenation and an Impella device. Based on significant hemoconcentration, decreased plasma protein levels, and pathologic findings in myocardial specimens, the patient was diagnosed with vaccination-induced fulminant systemic capillary leak syndrome (SCLS) with severe cardiac dysfunction. This case highlights that SCLS can occur after COVID-19 mRNA vaccination and may be associated with cardiac dysfunction. In patients with cardiogenic shock, hemoconcentration, and hypoalbuminemia after vaccination, SCLS should be considered.

Capillary hyperpermeability syndrome: A fatal complication of acute leukaemia: Case report and review

Introduction

The capillary hyperpermeability syndrome is a rare disease that should be suspected in the presence of recurrent generalized edema without obvious cause, which may be idiopathic or secondary.

Case presentation

In this case, we report a Clarkson syndrome secondary to an acute leukemia affecting a 4-year-old child admitted to the emergency room in respiratory and hemodynamic distress with a generalized oedematous syndrome and a bone marrow failure syndrome. Laboratory tests concluded that the patient was suffering from an acute lymphoblastic leukemia, hypoalbuminemia, pericardial effusion, and the absence of any other cause that is in favor of a capillary leak syndrome.In spite of the filling and the introduction of drugs, the cardio respiratory arrest could not be recovered and the child died 24h after his admission.

Discussion

It is a rare pathology described for the first time in 1960, generally secondary to a pathological state and more rarely idiopathic, to be evoked in front of clinical and biological parameters which are hypoalbuminemia, hemiconcentration and hypoperfusion, after having eliminated a sepsis in the first place.The treatment is based on the management of the acute phase by filling with crystalloids, drugs or even steroids, and as a preventive treatment of relapses immunoglobulins or theophylline are used.

Conclusion

The evolution can be quickly fatal, that's why it is necessary to know how to evoke this syndrome in front of a similar clinical presentation.

•

Capillary hyperpermeability syndrome is a rare cause of generalized edema.

•

The diagnosis is made on the basis of hypoalbuminemia, hemoconcentration, and hypoperfusion.

•

A monoclonal gammopathy type igG is rarely found in children unlike in adults.

•

Relapse prevention remains a very important part of treatment with immunoglobulin, theophylline or anti TNF alpha.

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.