This cross-sectional study was conducted to determine the incidence of autoantibodies to phospholipids and coagulation proteins in children with acute varicella zoster virus (VZV) infection. Study groups included children with VZV alone or complicated by purpura fulminans and/or thromboembolism. VZV naïve children and children who had VZV Ͼ1 y before sample collection formed a control group. Blood was assayed for the following: free protein S (PS), protein C, antithrombin, and prothrombin; antibody binding to these proteins; lupus anticoagulant; anticardiolipin antibody; antiphospholipid antibodies; and prothrombin fragment 1ϩ2. Data regarding coinfections was collected. Forty-three VZV-infected children showed an increased frequency of lupus anticoagulant, anticardiolipin antibody, antiphospholipid antibodies, and autoantibodies to PS, protein C, prothrombin, and antithrombin in comparison to 52 children without acute VZV (p Ͻ 0.0001). Seventeen children with VZV and purpura fulminans and/or thromboembolism showed a statistically significant decrease in free PS, significantly increased PS IgG antibody, and significantly increased prothrombin fragment 1ϩ2 (p Ͻ 0.0001) compared with the group without acute VZV and the group with uncomplicated VZV. Twenty-six children with uncomplicated VZV showed In a 1990 review, Francis (1) reported the association of VZV and/or streptococcal infection in 30% of children with idiopathic purpura fulminans. Subsequently, acquired free PS deficiency was described in children and adults with acute VZV infection and PFϮTE (2-8). We reported the LA and free PS deficiency in seven previously healthy children with acute VZV infection complicated by PFϮTE (6). We previously found evidence suggestive of an autoimmune cause of acquired PS deficiency.We now report a cross-sectional study designed to determine the prevalence of autoantibodies directed against a variety of phospholipids and coagulation proteins in previously healthy children with VZV infection. The aim of this study was to compare results obtained on blood samples from children with uncomplicated acute VZV infection with samples from children with acute VZV complicated by symptomatic PFϮTE. It was hypothesized that coagulation abnormalities in the children with symptomatic PFϮTE would be more prevalent and more severe but not intrinsically different from those found in healthy children with uncomplicated VZV infection.
METHODS
Clinical MethodsThis cross-sectional study was performed with the approval of the Colorado Multi-Institutional Review Board and the Pediatric Clinical Research Center at The Children's Hospital of Denver. Informed consent and assent forms were signed before enrollment in the study.