L15
Case Report of a Previously Unreported Type of DOCK8 Deficiency
Sunday, March 6, 2016
South Exhibit Hall H (Convention Center)
Stephen Dinetz, MD, Betty B. Wray, MD FAAAAI
Rationale: Dedicator of cytokinesis 8 (DOCK8) deficiency is an autosomal recessive hyper-IgE syndrome characterized by recurrent bacterial, viral and/or fungal infections, atopic dermatitis and food allergies. Previous reports demonstrate either autosomal recessive or compound heterozygosity defects within the DOCK8 gene.

Methods: Genetic sequencing evaluation of DOCK8, SPINK5, STAT3, and TYK2 were performed by GeneDx.

Results: The patient presented with severe atopic dermatitis, eczema herpeticum, and severe food allergies. Immune evaluation showed decreased NK cell function, absent CD45+ total lymphocyte and CD3+ T cell responses to Tetanus toxoid and a serum IgE of 15,828 kU/L. Targeted comparative genomic hybridization revealed a heterozygous defect, c.624-12 T>A, a variant of unknown significance in the DOCK8 gene.

Conclusions: The c.624012 T>A variant is a previously unreported mutation that is likely responsible for the findings in this patient. This is the first reported case of this heterozygous mutation and may be clinically useful in the diagnosis and treatment of severe atopic dermatitis that does not fit the established criteria for previously reported hyper-IgE syndromes.