Increased fibrinolysis-induced bradykinin formation in hereditary angioedema confirmed using stored plasma and biotechnological inhibitors

Classification, Diagnosis, and Pathology of Angioedema Without Hives

A clear disease classification schema coupled with an understanding of the specific mechanisms involved in the different types of angioedema without hives informs the diagnostic assessment. The recommended approach involves several key steps. Foremost is the recognizing of the clinical clues which allow for the differentiation of mast cell-mediated disorders from bradykinin-mediated angioedema. Enhanced vascular permeability related to bradykinin is of critical importance to identify given the implications for disease morbidity and risk of mortality. The ability to efficiently categorize and diagnose all forms of angioedema results in improved patient outcomes.

Tenecteplase-associated orolingual angioedema: A case report and literature review

PURPOSE

Orolingual angioedema (OA) secondary to administration of thrombolytic therapy is a rare, but serious, known adverse effect. Despite the lack of robust evidence for their use, C1 esterase inhibitors are recommended by guidelines for the treatment of refractory thrombolytic-associated OA. This report highlights the use of a C1 esterase inhibitor in a patient with tenecteplase-associated OA unresolved by antihistamine and corticosteroid therapy.

SUMMARY

A 67-year-old white male with a history of hypertension managed with lisinopril presented to the emergency department with acute onset of slurred speech and left-sided hemiparesis. Following workup, an outside hospital's neurology stroke team suspected an acute infarct and determined the patient to be a candidate for tenecteplase. Approximately 1 hour after tenecteplase administration, the patient began complaining of dyspnea and mild oral angioedema. Immediate interventions for OA management included intravenous therapy with dexamethasone 10 mg, diphenhydramine 25 mg, and famotidine 20 mg. After an additional 30 minutes, the patient's OA symptoms continued to progress and a C1 esterase inhibitor (Berinert) was administered. Shortly after administration of the C1 esterase inhibitor, the patient's symptoms continued to worsen, ultimately leading to endotracheal intubation. Following intubation, symptom improvement was noted, and the patient was safely extubated after 30 hours.

CONCLUSION

Although rare, OA is a potentially life-threatening complication of tenecteplase therapy and requires prompt pharmacological intervention to optimize patient outcomes. Currently, no single agent or treatment algorithm exists that has shown significant efficacy or safety in the setting of thrombolytic-associated OA. Until data are available for C1 esterase inhibitors in this application, these inhibitors should only be considered if there is continued symptom progression after intravenous administration of corticosteroids and antihistamines.

Alteplase associated Orolingual angioedema: A case report and literature review

OBJECTIVE

Orolingual angioedema (OA) is a rare but life-threatening complication of intravenous thrombolysis using alteplase. Angioedema can be caused by almost any medication. Administration of recombinant tissue plasminogen activator causes atypical angioedema. This study aimed to investigate factors related to and treatment of OA after thrombolysis with alteplase.

CASE REPORT

We describe the case of a 53-year-old man with a history of hypertension managed with enalapril, who presented with ischemic cerebrovascular stroke. Intravenous alteplase was administered, and within 54 minutes, the patient developed severe orolingual edema requiring emergent intubation. Subsequent imaging revealed an acute-to-subacute infarct in the left occipital lobe of the posterior cerebral artery.

RESULTS

The most common factor for increased risk of OA after recombinant tissue plasminogen activator was concomitant use of angiotensin-converting enzyme inhibitors (ACEI).

CONCLUSION

Before intravenous thrombolytic therapy, patients should be asked if they have a history of allergies, are currently using ACEI, and try to avoid using ACEI antihypertensive drugs before and after thrombolytic therapy.

Picomolar Sensitivity Analysis of Multiple Bradykinin-Related Peptides in the Blood Plasma of Patients With Hereditary Angioedema in Remission: A Pilot Study

Background

Hereditary angioedema (HAE) is a rare autosomal dominant disease; the most well understood forms concern the haplodeficiency of C1 esterase inhibitor (C1INH) and a gain of function mutation of factor XII (FXII). The acute forms of these conditions are mediated by an excessive bradykinin (BK) formation by plasma kallikrein.

Methods

A validated LC-MS/MS platform of picomolar sensitivity developed for the analysis of eleven bradykinin-related peptides was applied to the plasma of HAE-C1INH and HAE-FXII sampled during remission.

Results

In HAE-C1INH plasma, the concentrations of the relatively stable BK1−5 fragment (mean ± S.E.M.: 12.0 ± 4.2 pmol/L), of BK2−9 (0.7 ± 0.2 pmol/L) and of the sums of BK and its tested fragments (18.0 ± 6.4 pmol/L) are significantly greater than those recorded in the plasma of healthy volunteers (1.9 ± 0.6, 0.03 ± 0.03 and 4.3 ± 0.8 pmol/L, respectively), consistent with the previous evidence of permanent plasma kallikrein activity in this disease. Kinin levels in the plasma of HAE-FXII patients did not differ from controls, suggesting that triggering factors for contact system activation are not active during remission.

Conclusion

BK1−5, BK2−9 and the sum of BK and its fragments determined by the sensitive LC-MS/MS technique are proposed as potential biomarkers of HAE-C1INH in remission while this was not applicable to HAE-FXII patients.

[Neonatal capillary leak syndrome]

Neonatal capillary leak syndrome is a clinical syndrome with definite etiology or predisposing factors and has the manifestations of hypotension, hemoconcentration, hypoproteinemia, and systemic edema. This disease often has critical conditions and may lead to multiple organ failure and even death. There are still controversies over the diagnosis and treatment of this disease. This article summarizes the recent advances in the diagnosis and treatment of neonatal capillary leak syndrome, in order to improve the diagnosis and treatment of this disease among clinicians.

In Vitro Modeling of Bradykinin-Mediated Angioedema States

Kinins (peptides related to bradykinin, BK) are formed from circulating substrates, the kininogens, by the action of two proteases, the kallikreins. The only clinical application of a BK receptor ligand, the B₂ receptor antagonist icatibant, is the treatment of the rare hereditary angioedema (HAE) caused by the deficiency of C1-esterase inhibitor (C1-INH). Less common forms of HAE (genetic variants of factor XII, plasminogen, kininogen) are presumably mediated by increased BK formation. Acquired forms of BK-mediated angioedema, such as that associated with angiotensin-I converting enzyme (ACE) inhibition, are also known. Antibody-based analytical techniques are briefly reviewed, and support that kinins are extremely short-lived, prominently cleared by ACE. Despite evidence of continuous activation of the kallikrein–kinin system in HAE, patients are not symptomatic most of the time and their blood or plasma obtained during remission does not generate excessive immunoreactive BK (iBK), suggesting effective homeostatic mechanisms. HAE-C1-INH and HAE-FXII plasmas are both hyperresponsive to fibrinolysis activation. On another hand, we suggested a role for the alternate tissue kallikrein–kinin system in patients with a plasminogen mutation. The role of the BK B₁ receptor is still uncertain in angioedema states. iBK profiles under in vitro stimulation provide fresh insight into the physiopathology of angioedema.

Measurement of Bradykinin Formation and Degradation in Blood Plasma: Relevance for Acquired Angioedema Associated With Angiotensin Converting Enzyme Inhibition and for Hereditary Angioedema Due to Factor XII or Plasminogen Gene Variants

Bradykinin (BK)-mediated angioedema (AE) states are rare acquired or hereditary conditions involving localized edema of the subcutaneous and submucosal tissues. Citrated plasma from healthy volunteers or patients with hereditary angioedema (HAE) with normal level of C1-inhibitor (C1-INH) was used to investigate pathways of BK formation and breakdown relevant to AE physiopathology. The half-life of BK (100 nM) added to normal plasma was 34 s, a value that was increased ~12-fold when the angiotensin converting enzyme (ACE) inhibitor enalaprilat (130 nM) was added (enzyme immunoassay measurements). The BK half-life was similarly increased ~5-fold following 2 daily oral doses of enalapril maleate in healthy volunteers, finding of possible relevance for the most common form of drug-associated AE. We also addressed the kinetics of immunoreactive BK (iBK) formation and decline, spontaneous or under three standardized stimuli: tissue kallikrein (KLK-1), the particulate material Kontact-APTT™ and tissue plasminogen activator (tPA). Relative to controls, iBK production was rapid (10–20 min) and very intense in response to tPA in plasma of female heterozygotes for variants in gene F12 coding for factor XII (FXII) (p.Thr328Lys, 9 patients; p.Thr328Arg, one). An increased response to Kontact-APTT™ and an early tPA-induced cleavage of anomalous FXII (immunoblots) were also observed. Biotechnological inhibitors showed that the early response to tPA was dependent on plasmin, FXIIa and plasma kallikrein. Results from post-menopausal and pre-menopausal women with HAE-FXII were indistinguishable. The iBK production profiles in seven patients with the plasminogen p.Lys330Glu variant (HAE-PLG) did not significantly differ from those of controls, except for an unexpected, rapid and lanadelumab-resistant potentiation of KLK-1 effect. This enzyme did not cleave plasminogen or factor XII, suggesting a possible idiosyncratic interaction of the plasminogen pathogenic variant with KLK-1 activity. KLK-1 abounds in salivary glands and human saliva, hypothetically correlating with the clinical presentation of HAE-PLG that includes the swelling of the tongue, lips and contiguous throat tissues. Samples from HAE patients with normal C1-INH levels and F12 gene did not produce excessive iBK in response to stimuli. The ex vivo approach provides physiopathological insight into AE states and supports the heterogeneous physiopathology of HAE with normal C1-INH.

Lanadelumab for the prevention of attacks in hereditary angioedema

Introduction: Hereditary angioedema (HAE) with C1 esterase inhibitor deficiency (C1-INH-HAE) is a rare disease that manifests with cutaneous and/or submucosal swellings due to uncontrolled activation of the contact/kinin system. Attacks recur with unpredictable frequency and severity, laryngeal edema is potentially lethal, and the disease burden may severely disrupt patients' lives.Areas covered: This review provides an overview of lanadelumab, a human monoclonal antibody targeted against plasma kallikrein that was recently approved for prevention of symptoms in C1-INH-HAE.Expert opinion: The phase III HELP Study demonstrated the efficacy of lanadelumab in reducing HAE attacks. These positive results are being further confirmed in the open-label extension study. This agent addresses some of the limitations of existing prophylactic options as tolerability issues, the need for intravenous administration and frequent dosing. Therefore, lanadelumab can profoundly improve the quality of life of patients with C1-INH-HAE.