A rare cause of shock in cases of refractory hypotension, hypoproteinaemia and haemoconcentration.

Clinical Presentation, Management, and Prognostic Factors of Idiopathic Systemic Capillary Leak Syndrome: A Systematic Review

Characterizing drug-induced capillary leak syndromes using the World Health Organization VigiBase

Idiopathic systemic capillary leak syndrome (ISCLS) is a rare cryptogenic disorder characterized by recurrent hemoconcentration, hypoalbuminemia, edema, and hypotension due to extravascular fluid leakage. This is the first report that details uncommon extensive leukoencephalopathy caused by ISCLS upon a neuropathological investigation. A 68-year-old female had recurrent episodes of hemoconcentration, hypoalbuminemia, and generalized edema and was diagnosed with ISCLS. After 9years, brain magnetic resonance imaging (MRI) incidentally revealed extensive leukoencephalopathy without neurological deficits. Thorough examinations ruled out other disorders, and the cerebral involvement due to ISCLS was finally diagnosed. Three years later, she developed an acute-onset coma and status epilepticus together with hypotension and hemoconcentration, which were compatible with ISCLS recurrence. Electroencephalogram and MRI were correlated with a seizure arising from the left hemisphere. Extensive leukoencephalopathy did not show notable changes for 3years. Although treatment for ISCLS recurrence temporally improved hemoconcentration and consciousness, consciousness worsened again by marked edema of the left hemisphere, and she died of cerebral herniation. A brain autopsy revealed straggly perivascular plasma leakage around the small vessels of the deep white matter, which supported that the leukoencephalopathy was caused by ISCLS. Widespread myelin pallor and decreased axonal density with sparse astrogliosis and microgliosis were observed in the cerebral white matter and corresponded with a chronic change in the MRI. Current radiological and pathological observations revealed that frequent perivascular leakages could cause chronic leukoencephalopathy, were linked with the development of systemic capillary leakage in ISCLS, and provided insights into the mysterious pathophysiology.

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.

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Idiopathic Systemic Capillary Leak Syndrome Preceding Diagnosis of Infiltrating Lobular Carcinoma of the Breast With Quiescence During Neoadjuvant Chemotherapy

Idiopathic systemic capillary leak syndrome (SCLS) or “Clarkson disease” is a life-threatening disorder characterized by microvascular hyperpermeability-related recurrent “attacks” or “flares” of severe hypotension, edema, hemoconcentration, and hypoalbuminemia. A monoclonal protein, detected in the majority of the patients, serves as a valuable clue for the diagnosis of SCLS, a disorder with myriad non-specific prodromal and acute attack-related symptoms. Prompt recognition and timely institution of appropriate supportive care are critical. Restoration of normal perfusion requires judicious use of vasopressors, fluids, and occasionally diuretics. Prophylactic therapy with beta-2 agonists, methylxanthines, or intravenous immunoglobulin may reduce the frequency and severity of “attacks.” Although in the recent years we have gained a better understanding of the biology of this perplexing disorder, there remains a paucity of high-level evidence, particularly with regard to efficacy of the currently available therapies. This chapter outlines the diagnostic dilemmas and current approaches related to the management of idiopathic SCLS.

Increased vascular permeability is a prevalent feature in a wide spectrum of clinical conditions, but no effective treatments to restore the endothelial barrier are available. Idiopathic systemic capillary leak syndrome (ISCLS) is a life-threatening Paroxysmal Permeability Disorder characterized by abrupt, massive plasma extravasation. This condition serves as a robust model for investigating therapeutic approaches targeting interendothelial junctions. We conducted a single-center, interventional in vitro study at the Referral Center for ISCLS in Italy, involving four diagnosed ISCLS patients, aiming at investigating the effects of FX06, a Bβ15–42 fibrin-derived peptide binding to VE-Cadherin, on endothelial barrier exposed to intercritical and acute ISCLS sera. The Transwell Permeability Assay was used to assess the permeability of human umbilical vein endothelial cells (HUVECs) exposed to ISCLS sera with or without FX06 (50 µg/ml). Acute ISCLS serum was also tested in a three-dimensional microfluidic device. Nitric oxide (NO), VE-Cadherin localization, and cytoskeletal organization were also assessed. In two and three-dimensional systems, ISCLS sera increased endothelial permeability, with a more pronounced effect for acute sera. Furthermore, acute sera altered VE-Cadherin localization and cytoskeletal organization. NO levels remained unchanged. FX06 restored the endothelial barrier function by influencing cellular localization rather than VE-Cadherin levels. In conclusion, FX06 prevents and reverts the hyperpermeability induced by ISCLS sera. These preliminary yet promising results provide initial evidence of the in vitro efficacy of a drug targeting the underlying pathophysiological mechanisms of ISCLS. Moreover, this approach may hold potential for addressing hyperpermeability in a spectrum of clinical conditions beyond ISCLS.

Background: Clarkson’s disease, more known as idiopathic systemic capillary leak syndrome (SCLS) is a rare condition characterized by hypotensive episodes due to capillary hyperpermeability, which may be manifested by fluid accumulation in any organ or potential space, causing range of complications: respiratory failure (from pulmonary edema or pleural effusion), mesenteric hypoperfusion (from hepatic congestion and severe intestinal edema), compartment syndrome and rhabdomyolysis, and even shock from hypovolemia or cardiac tamponade. Very few cases of cardiac tamponade have been reported and certainly a serious and life-threatening complication. Case Summary: A 44-year-old female, reported to have intermittent episodes of angioedema aggravated by menstruation and infection, came in due to persistent hypotension. Patient presented with flu-like symptoms and tested positive for COVID – 19 infection. Initial laboratories revealed hemoconcentration, slightly elevated creatinine and hypoalbuminemia. Electrolytes and urinalysis were normal. 2D echocardiography showed large pericardial effusion with right atrial and ventricular collapse suggestive of cardiac tamponade, hence patient underwent emergency pericardial windowing. Initial chest X-ray was normal but repeat study showed pleural effusion on the 4th day of admission which was drained surgically. Additional diagnostic tests revealed negative for hepatitis, Mycoplasmal and Epstein-Barr virus. Direct and indirect Coomb’s test were also negative and Lupus panel was unremarkable. Serum free light chain panel showed suspicious for low level monotypic serum free lambda light chains (based only on the free light ratio). Immunopathology results showed no overt evidence of monoclonal bands. Protein electrophoresis pattern showed decreased albumin fraction and increased alpha, beta, and gamma fractions. C1 inhibitor was slightly elevated while serum tryptase was within normal values. Patient was managed as a case of idiopathic systemic capillary leak syndrome or Clarkson’s disease. Aside from judicious fluid resuscitation and vasopressors assist Methylprednisolone pulse therapy (MPPT) and intravenous immunoglobulin (IVIg) were administered. Patient was discharged with tapering doses of oral steroids and scheduled monthly IV immunoglobulin infusion. Conclusion: Cardiac tamponade, an uncommon yet severe and life-threatening complication of systemic capillary leak syndrome (SCLS) or Clarkson’s disease, requires immediate intervention. While the exact cause remains unclear, research suggests that during acute SCLS episodes and hyperinflammatory states, fluid accumulation in the pericardial space can impede ventricular filling, leading to hemodynamic compromise.

Clarkson’s syndrome, also known as idiopathic systemic capillary leak syndrome, is characterised by vascular hyperpermeability resulting in intravascular hypovolaemia and shock. A clinician should consider the diagnosis if other causes...

This case report describes the episodic occurrence of severe generalized edema in a young female patient, who developed hypertension with a massive hemoconcentration (hematocrit >0.5, hemoglobin >20g/dl) and hypoalbuminemia during the course of these acute disease phases. After the first two disease exacerbations were overcome, there was a complete regression of symptoms. After a long symptom-free interval, a new exacerbation occurred as a result of which critical organ ischemia occurred due to the severe hypotension and massive edema. Despite all treatment measures a severe compartment syndrome of the lower extemities with subsequent rhabdomyelosis developed. The patient ultimately died as a result of treatment-refractory cardiovascular failure. The idiopathic systemic capillary leak syndrome (SCLS, also known as Clarkson disease) is a rare and potentially life-threatening disease with a high mortality. Since the first description of the disease only approximately 500 cases have been published worldwide. The pathophysiology of this disease remains unclear despite all previous attempts at clarification. Regulation processes of endothelial permeability seem to be essentially disturbed. Affected patients have a monoclonal gammopathy of undetermined signficance conspicuously often; however, the knowledge of the limited treatment options is of fundamental importance for the prognosis and overall survival of patients.

Idiopathic systemic capillary leak syndrome presenting as septic shock: A case report

ABNORMAL PRESENTATION OF INFLUENZA A-RELATED SYSTEMIC CAPILLARY LEAK SYNDROME

ObjectiveThe term Idiopathic Systemic Capillary Leak Syndrome (ISCLS) refers to an uncommon condition of severe distributive shock, resulting from an abrupt shift of fluids and proteins from the intravascular to the interstitial compartment. We hypothesise that the autonomic nervous system (ANS) fails in regulating the response to hypovolemia in acute ISCLS and that ANS variables characterise the progression to the recovery.DesignProspective cohort study of patients admitted to ICU for severe ISCLS flares.SettingSingle, referral center in Italy for ISCLS.PatientsAnalysis of cardiovascular signals recorded during seven severe ISCLS attacks and one prodromal period in five patients.InterventionsANS was studied non-invasively by means of heart rate variability (HRV) and blood pressure variability analysis, as an estimation of vagal and sympathetic modulation directed to the heart and vessels. Heart rate and systolic arterial pressure (SAP) variability were also used to assess baroreflex sensitivity. ANS variables were measured during the subsequent phases which characterise ISCLS flares, namely the acute phase, the post-acute phase, and the recovery phase.Measurements and main resultsHRV was severely depressed during the acute phase accounting for the loss of ANS modulation during massive capillary extravasation. This phase was characterised by shock and impaired baroreflex control, which allowed SAP to oscillate driven by respiratory activity. Impending shock and transition from shock to a post-acute phase were marked by change of baroreflex spectral variables. The baroreflex control was fully restored during recovery.ConclusionsANS modulation and baroreflex control are severely impaired during the acute haemodynamic instability which characterises ISCLS crises and their progressive restoration may be a clue of improvement. ANS indices during ISCLS flares might serve as useful biomarkers, able to timely announce the transition from one phase to the subsequent one, thus helping to adapt therapy accordingly.

Clarkson disease, or monoclonal gammopathy–associated idiopathic systemic capillary leak syndrome (ISCLS), is a rare, relapsing-remitting disorder featuring the abrupt extravasation of fluids and proteins into peripheral tissues, which in turn leads to hypotensive shock, severe hemoconcentration, and hypoalbuminemia. The specific leakage factor(s) and pathways in ISCLS are unknown, and there is no effective treatment for acute flares. Here, we characterize an autonomous vascular endothelial defect in ISCLS that was recapitulated in patient-derived endothelial cells (ECs) in culture and in a mouse model of disease. ISCLS-derived ECs were functionally hyperresponsive to permeability-inducing factors like VEGF and histamine, in part due to increased endothelial nitric oxide synthase (eNOS) activity. eNOS blockade by administration of N(γ)-nitro-l-arginine methyl ester (l-NAME) ameliorated vascular leakage in an SJL/J mouse model of ISCLS induced by histamine or VEGF challenge. eNOS mislocalization and decreased protein phosphatase 2A (PP2A) expression may contribute to eNOS hyperactivation in ISCLS-derived ECs. Our findings provide mechanistic insights into microvascular barrier dysfunction in ISCLS and highlight a potential therapeutic approach.