Deficiency of Adenosine Deaminase 2: Clinical Manifestations, Diagnosis, and Treatment

Deficiency of adenosine deaminase 2 (DADA2) is a monogenic vasculitis syndrome caused by biallelic mutations in the adenosine deaminase 2 gene. The diagnosis of DADA2 is confirmed by decreased enzymatic activity of ADA2 and genetic testing. Symptoms range from cutaneous vasculitis and polyarteritis nodosa-like lesions to stroke. The vasculopathy of DADA2 can affect many organ systems, including the gastrointestinal and renal systems. Hematologic manifestations occur early with hypogammaglobulinemia, lymphopenia, pure red cell aplasia, or pancytopenia. Treatment can be challenging. Tumor necrosis factor inhibitors are helpful to control inflammatory symptoms. Hematopoietic stem cell transplant may be needed to treat refractory cytopenias, vasculopathy, or immunodeficiency.

Leg muscle involvement in polyarteritis nodosa (limited form)-A rare case report

Polyarteritis nodosa is a necrotizing arteritis involving small and medium vessels. Polyarteritis nodosa can have variable presentations depending upon the organ involved. It can either present as a diffuse disease or a limited form confined to a particular organ. Isolated muscular involvement in this disease is rare, which may present as myalgia, nonspecific fever, weight loss or even as claudication. The imaging pattern on ultrasound and MRI can help diagnose this condition in the background of clinical history and muscle biopsy is confirmatory. We present a case of 15 years old boy who presented with fever, weight loss, myalgia in leg region. MRI and ultrasound examination showed perivascular inflammation in calf muscles with a characteristic "cotton wool" pattern of enhancement on contrast study.

A Report of 2 Cases of Kidney Involvement in ADA2 Deficiency: Different Disease Phenotypes and the Tissue Response to Type I Interferon

Adenosine deaminase 2 (ADA2) deficiency is a rare autosomal recessive disease that is caused by loss-of-function mutations in the ADA2 gene. It is considered a monogenic form of polyarteritis nodosa and frequently is positive for a type I interferon (IFN) signature. Renal manifestations in ADA2 deficiency are poorly characterized. We herein report 2 cases of ADA2 deficiency with different kidney patterns due, respectively, to a predominantly macroscopic and microscopic vasculopathy, and review the literature on kidney disease in ADA2 deficiency. Patient 1 presented with a spontaneous perirenal hematoma; angiography demonstrated multiple microaneurysms but no further defects of the renal parenchyma; his kidney function remained normal. Patient 2 experienced slowly deteriorating kidney function and proteinuria. No major angiographic abnormalities were detected, while kidney biopsy revealed massive vasculopathy resembling chronic thrombotic microangiopathy (TMA) of the small and medium-sized vessels. Both patients had a positive peripheral type I IFN signature. In immunofluorescence staining of a kidney biopsy sample from patient 2, we observed marked expression of the type I IFN-induced protein MXA within endothelial cells, especially in vessels with TMA, and in infiltrating T cells. Our findings confirm that the kidney phenotype of ADA2 deficiency results from small and medium-sized vessel vasculopathy and suggest that type I IFN may be involved in the pathogenesis of kidney lesions.

Successful treatment of polyarteritis nodosa with intestinal necrosis in a Chinese boy: a case report

Polyarteritis nodosa (PAN) is a systemic necrotizing inflammatory disease of the medium and small arteries which has variable clinical manifestations, course, and organ involvement. Intestinal necrosis resulting from PAN is rare, and successful treatment of such cases is even more uncommon. Here, we report the first successful treatment of PAN with intestinal necrosis in a young Chinese child. A 5-year-old boy was admitted to our hospital with a 5-day history of abdominal pain. The patient underwent an emergency exploratory laparotomy, which showed skipping necrosis of the intestinal wall. Intestinal resection and anastomosis failed to improve his abdominal pain. The patient's blood pressure remained high (140/120 mmHg), despite captopril treatment. The erythrocyte sedimentation rate (ESR) and D-dimer level were also elevated at (106.00 mm/h and 11.16 mg/L, respectively), as was the 24-hour urine protein (197.6 mg/24 h). Echocardiography revealed that the diameters of the left and right coronary arteries were increased (0.45 and 0.49 cm, respectively). Ultrasound showed polyarteritis in the anterior tibial, radial, iliac, and renal arteries. Histopathologic examination revealed elastic fiber rupture and partial mesenteric arteriolar stenosis with occlusion. After 2 months of treatment with systemic methylprednisolone, cyclophosphamide, and prednisone, the patient's abdominal pain was relieved. Furthermore, the patient's ESR and D-dimer levels had reduced to 5 mm/h and 0.63 mg/L, respectively; his 24-hour urine protein was normal (60.0 mg/24 h); and his blood pressure had dropped to 101/46 mmHg. The left and right coronary arteries had reduced to 0.35 and 0.38 cm in diameter, respectively; however, no significant improvement was observed in the other vessels involved. Unfortunately, the child's parents did not continue to seek medical attention; therefore, his long-term outcome is unknown. In this case, the patient was operated on immediately after symptom onset. The postoperative infection was also quickly controlled, avoiding the occurrence of septic shock. Vascular B-ultrasound and pathology aided in establishing a clear and timely diagnosis, which allowed systematic medical treatment to be delivered, achieving good short-term results.

Cerebral involvement in systemic vasculitides: Extracts from the guideline of the German neurological society

Cerebral vasculitis is a rare disorder but plays a major role in the differential diagnosis of stroke, encephalopathy and headache. This guideline was developed in order to support clinicians in the diagnosis and treatment of cerebral manifestations of systemic vasculitides and rheumatic diseases. It is based on a medline research and was developed in a modified Delphi process and approved by the involved societies. This article is an abridged and translated version of the guideline published in DGNeurologie: Berlit, P. & Krämer, M. DGNeurologie (2018) 1: 17. 10.1007/s42451-018-0001-y.

Thrombosed Aneurysm of the Posterior Inferior Cerebellar Artery and Lateral Medullary Ischemia as the Initial Presentation of Polyarteritis Nodosa: Case Report and Literature Review

A 27-year-old woman with a previously undiagnosed polyarteritis nodosa (PAN) developed lateral medullary stroke related to a thrombosed posterior inferior cerebellar artery (PICA)-origin aneurysm. A concurrent thrombosis of the PICA was identified on high-resolution 3-dimensional CUBE T1 magnetic resonance imaging sequence at 3 T. Body computed tomography angiography, magnetic resonance imaging-magnetic resonance angiography, and digital angiography revealed multiple tiny aneurysms of the visceral arteries and bilateral kidney infarcts. On the basis of these findings and of laboratory data, the patient was diagnosed as having PAN. Intracranial aneurysms (IAs) are extremely rare in PAN and usually manifest as subarachnoid or cerebral hemorrhage. Ischemic manifestation of small thrombosed IA is a rare occurrence. This case highlights (1) an uncommon complication in patients with PAN (16 other cases of IAs in patients with PAN found in the literature), (2) an unusual initial presentation of PAN, and (3) a thrombosed PICA-origin aneurysm responsible for an ischemic stroke and for secondary thrombosis of the parent vessel.