CARD11 encodes a scaffold protein essential for antigen receptor signaling in B and T lymphocytes through activation of the nuclear factor kappa B pathway. Pathogenic variants disrupt lymphocyte activation and immune regulation, resulting in a spectrum of immune dysregulation characterized by atopic dermatitis, recurrent infections, and variable immunodeficiency. Recognition of CARD11-associated disease in adults with refractory eczema and chronic fungal infection remains limited.
A 35-year-old male with persistent atopic dermatitis, bronchial asthma, and recurrent mucocutaneous fungal infections presented with chronic erythematous, pruritic eczema affecting the dorsum and soles of the feet for five years, with recent worsening causing fissuring, bleeding, and impaired quality of life. Family history was significant for eczema and fungal infections affecting his father, brother, and grandfather. Patch testing was negative. Genetic testing identified a heterozygous CARD11 frameshift variant (c.2891delG, p.Ser964fs*101), classified as likely pathogenic and consistent with autosomal dominant CARD11-associated immunodeficiency. Topical corticosteroids and tacrolimus provided limited benefit. Dupilumab was initiated, resulting in marked clinical improvement. Posaconazole was discontinued due to intolerance.
This case demonstrates adult presentation of CARD11-associated immunodeficiency with prominent atopic dermatitis and chronic fungal susceptibility. The strong family history supports autosomal dominant inheritance. Targeted biological therapy with dupilumab provided effective control of severe eczema despite underlying immune dysregulation.
CARD11-associated immunodeficiency should be considered in patients with refractory atopic dermatitis, fungal infections, and relevant family history. Early genetic diagnosis enables appropriate management and targeted therapy, improving clinical outcomes and guiding long-term follow-up.
