Cases of acquired C1 inhibitor deficiency treated with rituximab

Angioedema Due to Acquired C1-Inhibitor Deficiency Without Hematological Condition: A Multicenter French Cohort Study of 34 Patients

BACKGROUND

Angioedema (AE) due to acquired C1-inhibitor deficiency (AAE-C1-INH) is a rare disease associating recurrent edema of the mucosa and skin. Several underlying diseases have been reported, mainly lymphoproliferative diseases and monoclonal gammopathy. However, 15% to 20% of patients never exhibit such a hematological condition.

OBJECTIVE

To analyze specific features of patients with AAE-C1-INH without a hematological condition.

METHODS

This is a multicenter, retrospective cohort study of patients with AAE-C1-INH without a hematological condition included from January 1999 to May 2024 in the French national CREAK (Centre de reference des angioedèmes à kinine) registry. The clinical and biological characteristics of patients were detailed and then compared with those of patients with AAE-C1-INH associated with lymphoid hemopathies or monoclonal gammopathy.

RESULTS

Thirty-four patients were included. All patients displayed a functional C1-INH below 50% of the reference value, 26 (76%) also had a decreased C1-INH antigen level, and 26 (76%) displayed anti-C1-INH antibodies. After a median follow-up of 65 months, 4 (12%) patients were in spontaneous complete remission of AE; 15 (44%) were in complete response under long-term prophylactic treatment. Compared with 75 patients with lymphoma-associated AAE-C1-INH, patients with AAE-C1-INH without a hematological condition displayed a higher incidence of anti-C1-INH antibodies and received more frequently symptomatic or prophylactic treatment with a lower remission rate at last follow-up. Clinical and biological features of patients with AAE-C1-INH without a hematological condition were similar to those of 30 patients with monoclonal gammopathy-associated AAE-C1-INH.

CONCLUSIONS

AAE-C1-INH without a hematological condition displays a different clinical and biological presentation from lymphoma-associated AAE-C1-INH. No autoimmune disease was identified. Unlike rituximab, long-term prophylaxis seems to prevent AE attacks among these patients.

Efficacy and Safety of Rituximab-Based Treatments in Angioedema With Acquired C1-Inhibitor Deficiency

BACKGROUND

Angioedema (AE) due to acquired C1-inhibitor (C1-INH) deficiency (AAE-C1-INH) is related to excessive consumption of C1-INH or to anti-C1-INH antibodies, and is frequently associated with lymphoproliferative syndromes or monoclonal gammopathies. Standard of care for prophylactic treatment in this condition is not established. Rituximab may be effective to prevent attacks, especially if the lymphoid hemopathy is controlled, but data are scarce.

OBJECTIVE

To evaluate efficacy of rituximab in AAE-C1-INH.

METHODS

A retrospective multicenter study was carried out in France, including patients with AAE-C1-INH treated with rituximab between April 2005 and July 2019.

RESULTS

Fifty-five patients with AAE-C1-INH were included in the study, and 23 of them had an anti-C1-INH antibody. A lymphoid malignancy was identified in 39 patients, and a monoclonal gammopathy in 9. There was no associated condition in 7 cases. Thirty patients received rituximab alone or in association with chemotherapy (n = 25). Among 51 patients with available follow-up, 34 patients were in clinical remission and 17 patients had active AE after a median follow-up of 3.9 years (interquartile range, 1.5-7.7). Three patients died. The presence of anti-C1-INH antibodies was associated with a lower probability of AE remission (hazard ratio, 0.29 [95% CI, 0.12-0.67]; P = .004). Relapse was less frequent in patients with lymphoma (risk ratio, 0.27 [95% CI, 0.09-0.80]; P = .019) and in patients treated with rituximab and chemotherapy (risk ratio, 0.31 [95% CI, 0.12-0.79]; P = .014).

CONCLUSIONS

Rituximab is an efficient and well-tolerated therapeutic option in AE, especially in lymphoid malignancies and in the absence of detectable anti-C1-INH antibodies.

Where we are with acquired angioedema due to C1 inhibitor deficiency: A systematic literature review

Acquired angioedema due to C1 inhibitor deficiency (C1-INH-AAE) is a rare disease characterized by adult-onset recurrent non-urticarial angioedema with low levels of C1-INH. It is associated with lymphoproliferative disorders, and treatments are off-label with variable success. We conducted a systematic literature review to include patients with C1-INH-AAE identified in PubMed and Embase databases between January 2006 and February 2021. Clinical features of these patients were summarized, and factors associated with disease remission were explored. A total of 121 patients were included in the current study with a median age at diagnosis of 64 years and 45.5% being male. An associated disease was recorded in 94 patients (77.7%), and lymphoproliferative disorder was the most reported (59/94, 62.8%). Anti-C1-INH autoantibodies were present in 45 of 71 patients (63.4%). Factors impacting disease remissions included age (odds ratio [OR] 0.951, 95% confidence interval [CI] 0.909-0.994, p = 0.027), male (OR 0.327, 95% CI 0.124-0.866, p = 0.025), presence of monoclonal gammopathy (OR 0.133, 95% CI 0.041-0.429, p = 0.001), requirement of specific on-demand treatment (OR 0.216, 95% CI 0.066-0.709, p = 0.012) and rituximab use (OR 2.865, 95% CI 1.038-7.911, p = 0.042). A total of nine patients (7.4%) died at last follow up and most were unrelated to C1-INH-AAE. Our results imply that C1-INH-AAE is primarily associated with underlying B or plasma cell abnormalities, and clone-directed therapies could be promising options for its long-term management.

Case report presenting the diagnostic challenges in a patient with recurrent acquired angioedema, antiphospholipid antibodies and undetectable C2 levels

Background

Angioedema secondary to acquired C1 inhibitor deficiency (AAE) is a rare disease. It usually is associated with lymphoproliferative disorders. We present a case of AAE in a patient with antiphospholipid syndrome (APS), a non-Hodgkin lymphoproliferative disorder (NHL) with undetectable levels of C2, C4, and an undetectable CH50. The co-existence of AAE, APS, and NHL, with an undetectable C2 level, to the best of our knowledge, has never before reported together in the same patient.

Case presentation

A patient with a recent history of thrombosis presented with recurrent episodes of angioedema. The workup revealed undetectable levels of C2, C4 and undetectable CH50. Quantitative levels of C1 inhibitor and C1q were low. C1 inhibitor function was less than 40%. Anti-cardiolipin antibodies were found. The patient was initially treated on demand with intravenous plasma-derived human C1-INH concentrates, (Cinryze^® Shire). Later the patient received prophylactic therapy with danazol. She was diagnosed with lymphoma 3 years after her first episode of angioedema. Single agent therapy with rituximab was not only effective in treating her lymphoma but also preventing further episodes of angioedema. Anti-cardiolipin antibody titers also declined. Additionally, marked early primary pathway complement component abnormalities and CH50 also corrected, although incomplete normalization of C4 proved to be due to a heterozygous C4 deficiency.

Conclusion

This case shows the unique association of AAE, APS and NHL in a patient with undetectable levels of early complement components. Additionally, this case also shows for the first time the effectiveness of rituximab therapy in all three disease states while co-existing simultaneously in the same patient.

The Journal of Allergy and Clinical Immunology: In Practice - 2016 Year in Review

As editors, we concluded that it would be helpful to our readers to write a Year in Review article that highlights the Review, Original, and Clinical Communication articles published in 2016 in The Journal of Allergy and Clinical Immunology: In Practice. We summarized articles on the topics of asthma, rhinitis/rhinosinusitis, food allergy, anaphylaxis, drug allergy, urticarial/angioedema, eosinophilic disorders, and immunodeficiency. Within each topic, epidemiologic findings are presented, relevant aspects of prevention are described, and diagnostic and therapeutic advances are enumerated. Diagnostic tools described include history, skin tests, and in vitro tests. Treatments discussed include behavioral therapy, allergen avoidance therapy, positive and negative effects of pharmacologic therapy, and various forms of immunologic and desensitization management. We hope this review will help you, our readers, consolidate and use this extensive and practical knowledge for the benefit of your patients.