Management of Atopy with Dupilumab and Omalizumab in CADINS Disease

The caspase activation and recruitment domain 11 (CARD11) gene encodes a scaffold protein required for lymphocyte antigen receptor signaling. Dominant-negative, loss-of-function (LOF) pathogenic variants in CARD11 result in CARD11-associated atopy with dominant interference of NF-κB signaling (CADINS) disease. Patients with CADINS suffer with severe atopic manifestations including atopic dermatitis, food allergy, and chronic spontaneous urticaria in addition to recurrent infections and autoimmunity. We assessed the response of dupilumab in five patients and omalizumab in one patient with CADINS for the treatment of severe atopic symptoms. CARD11 mutations were validated for pathogenicity using a T cell transfection assay to assess the impact on activation-induced signaling to NF-κB. Three children and three adults with dominant-negative CARD11 LOF mutations were included. All developed atopic disease in infancy or early childhood. In five patients, atopic dermatitis was severe and recalcitrant to standard topical and systemic medications; one adult suffered from chronic spontaneous urticaria. Subcutaneous dupilumab was initiated to treat atopic dermatitis and omalizumab to treat chronic spontaneous urticaria. All six patients had rapid and sustained improvement in atopic symptoms with no complications during the follow-up period. Previous medications used to treat atopy were able to be decreased or discontinued. In conclusion, treatment with dupilumab and omalizumab for severe, refractory atopic disease in patients with CADINS appears to be effective and well tolerated in patients with CADINS with severe atopy.

Hyper-IgE and Carcinoma in CADINS Disease

Background

Atopic dermatitis (AD) affects up to 25% of children and 10% of adults in Western countries. When severe or recurrent infections and exceedingly elevated serum IgE levels occur in AD patients, an inborn error of immunity (IEI) may be suspected. The International Union of Immunological Societies classification lists variants in different genes responsible for so-called Hyper-IgE syndromes. Diagnosing an underlying IEI may influence treatment strategies.

Methods

Clinical and diagnostic workup of family members are presented including a detailed immunological description and histology of the carcinoma. Functional testing of the novel variant in CARD11 underlying ‘CARD11-associated atopy with dominant interference of NF-kB signaling’ (CADINS) was performed.

Results

We report on an 18-year-old patient with a long-standing history of infections, accompanied by hypogammaglobulinemia, intermittent agranulocytosis, atopy, eosinophilia and colitis. The working diagnosis of common variable immunodeficiency was revised when a novel heterozygous CARD11 variant [c.223C>T; p.(Arg75Trp)] was identified. Functional studies confirmed this variant to have a dominant negative (DN) effect, as previously described in patients with CADINS. Five other family members were affected by severe atopy associated with the above variant, but not hypogammaglobulinemia. Malignancies occurred in two generations: an HPV-positive squamous cell carcinoma and a cutaneous T-cell lymphoma. So far, one patient is under treatment with dupilumab, which has shown marked benefit in controlling severe eczema.

Conclusion

The phenotypic spectrum associated with heterozygous CARD11 DN mutations is broad. Partial T-cell deficiency, diminished IFN-γ cytokine and increased IL-4 production, were identified as disease-causing mechanisms. Malignant disease associated with germline CARD11 DN variants has only been reported sporadically. HPV vaccination in teenage years, and cytology screening analogous with routine cervical swabs may be recommended. Treatment with dupilumab, a monoclonal antibody blocking interleukin-4- and interleukin-13 signaling, may be of benefit in controlling severe and extended AD for some patients as reported for STAT3 loss-of-function.