Introduction: DADA2 is a recently described auto-inflammatory disorder. It is caused by a biallelic deleterious mutations in the CECR1 gene encoding adenosine deaminase 2 (ADA2) enzime. The DADA2 would lead to endothelial damage and a skewing of monocytes into M1 pro-inflammatory macrophage. Clinically, patients display variable autoinflammation and vasculopathy (recurrent fevers, livedo reticularis, polyarteritis nodosa, lacunar ischemic strokes and intracranial hemorrhages), immunodeficiency and bone marrow failure.

Case Description: A 14-years-old boy presented with impaired sensitivity of the tongue. He has been manifesting a livedo reticularis for seven years with a previously diagnosis of cutaneous polyarteritis nodosa and one year ago presented a lacunar stroke involving the left paramedian caudal midbrain, when he presented left  partial oculomotor nerve palsy. Current brain MRI revealed multifocal ischemia in the territory of vertebrobasilar perforating arteries.

Results: Molecular testing on DNA sample demonstrated compound heterozygous CECR1 mutations and ADA2 deficiency was established. The therapeutic agent was changed to Adalimumab.

Conclusion/Discussion: DADA2 should be included in the differential diagnosis of young patients presenting with ischemic lesions located in the brain stem and deep gray matter, especially if they have additional systemic abnormalities. Timely diagnosis and treatment with anti-TNF-α agents have been proven efficient in DADA2 and should therefore be used as first line  therapy for the prevention of severe complications of the disease. As those patients presents a high risk of intracranial bleeding the role of anti-platelet and anticoagulant therapies in stroke-prophylaxis is discussed.