Adenosine deaminase 2 (DADA2) deficiency: 2 case reports
2Pediatric Department A, Edmond and Lily Safra Children's Hospital, Sheba Medical Center
3Rheumatology Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center
4Sheba Cancer Research Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center
Introduction
• Adenosine deaminase 2 deficiency, is a recently described rare autosomal recessive disorder, caused by loss of function in CERC1.
• It is thought that ADA2 has a role in endothelial and monocyte differentiation, thus ADA2 deficiency causes a vasculopathy and immune deficiency.
• There is a large phenotypic variability and Its manifestations include splenomegaly, cutaneous involvement, hematologic abnormalities, immunodeficiency and stroke.
Clinical presentation
• We report 2 cases of Arab-Muslim descent with ADA2 deficiency presented with fever, elevated inflammation markers and prominent neutropenia, which is not typically characteristic of this disorder.
• Both patients had a family history of a sibling presenting similar symptoms.
Genetics
• Patient’s genetic analysis by exome sequencing
Discussion
• ADA2 deficiency is a new autosomal recessive vasculitis with a broad clinical presentation.
• We showed two cases that presented with severe neutropenia, which has not been described as a main feature of the disorder.
• Genetic analysis by exome sequencing revealed two novel mutations in the gene CECR1.