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Purpose: Noonan syndrome (NS) is a congenital disorder characterized by various phenotypic features and congenital anomalies. Bleeding disorders are among the more serious, common, yet poorly defined complications associated with NS. As a means of focusing on these complications, we report three patients with stigmata of NS, each of whom had a combination of different hemostatic disorders, and review the literature on bleeding disorders in NS., Patients and Methods: The clinical course and hemostatic abnormalities in three patients with NS were studied, and a literature review on NS was undertaken., Results: The three patients we report had decreased coagulation factor levels (factors XI and II), von Willebrand disease, various levels of thrombocytopenia, and abnormal platelet function. The literature review on NS discloses multiple types of hemostatic abnormalities and a wide range of clinical presentations. A low level of coagulation factor XI is the most frequently described; thrombocytopenia and abnormal platelet function are also common., Conclusions: The existence of various types of bleeding disorders within one syndrome is unusual and requires further investigation. Recognition of this common complication in children with NS would aid both clinical management and understanding of the spectrum, the frequency, and perhaps even the basis of the hemostatic defects in this syndrome. We recommend performing coagulation screening tests in every patient with NS.

In this study we sought to determine whether factor VIII-reactive T lymphocytes were present in hemophilia A patients with inhibitor antibodies. Peripheral blood mononuclear cells (MNC) were obtained from 12 severe hemophilia A patients having high titer inhibitors, 4 severe hemophilia A patients without inhibitors and 5 normal male subjects. B cell-depleted MNC were cultured in serum-free medium in the absence or presence of 2 micrograms of recombinant human factor VIII (rFVIII) per ml, and cellular proliferation was assessed after 5 days of culture by measuring 3H-thymidine incorporation. rFVIII induced marked cellular proliferation in cultures of 4 of 12 inhibitor-positive hemophilia patients: fold increase over background (stimulation index, SI) of 7.8 to 23.3. The remaining 8 inhibitor-positive patients, the 4 hemophilia patients without inhibitors and the 5 normal subjects, all had lower proliferative responses to rFVIII, SI range = 1.6 to 6.0. As a group, the inhibitor-positive subjects had significantly higher proliferative responses to rFVIII than did the inhibitor-negative and normal subjects (p < 0.05 by t-test). Cell fractionation experiments showed that T lymphocytes were the rFVIII-responsive cell type, and that monocytes were required for T cell proliferation. Thus, rFVIII-reactive T lymphocytes are present in the peripheral circulation of some inhibitor-positive hemophilia A patients. These T cells may recognize FVIII in an antigen-specific manner and play a central role in the regulation of inhibitor antibody production.

To reduce the risk of pathogenic virus transmission associated with the therapeutic administration of plasma-derived anti-hemophilic factor (FVIIIc), a process utilizing anti-FVIIIc immunoaffinity chromatography to isolate FVIIIc has been developed. In addition, the starting cryoprecipitate solution has been treated with an organic solvent/detergent mixture to inactivate lipid-enveloped viruses. A final ion exchange chromatography step is used to further remove contaminants, e.g., anti-FVIIIc antibody, potentially leached with FVIIIc during the immunoaffinity step. The purified FVIII is stabilized for lyophilization and storage by the addition of human albumin. The monoclonal anti-FVIIIc antibody used in the immunoaffinity step of the process is not detectable in the final preparation. Viral reduction studies performed at specific steps of the process demonstrate that 11 logs of human immunodeficiency virus (HIV) and greater than 4-5 logs of other lipid-enveloped viruses are inactivated within the first 30 s of exposure to the solvent/detergent mixture and 4-5 logs of various model viruses, e.g. Endomyocarditis virus (EMC), are physically removed during washing of the immunoaffinity column. The lyophilized product is reconstituted using sterile water in a matter of seconds. The pharmacokinetics of Hemofil M were compared to those obtained using a standard heat-treated concentrate (Hemofil CT) in five severe factor VIII deficient hemophiliacs in a randomized, cross-over study. No statistically significant differences were observed in mean half life (p greater than 0.6) or median recovery (p = 0.4) between the two preparations. No clinically significant adverse effects were observed in patients receiving either FVIII preparation.(ABSTRACT TRUNCATED AT 250 WORDS)

A blinded randomized multicenter trial of two non-activated prothrombin complex concentrates was carried out to determine the clinical effectivity in the treatment of acute hemarthrosis in hemophiliac patients with inhibitors. The one product was prepared via DEAE Sephadex chromatography, while the second was fractionated via various precipitation procedures including polyethylene glycol. Equivalence of the two products was established with less than 15% difference in efficacy rates.

Patients with Hodgkin's disease (HD) have a high risk of overwhelming pneumococcal infections after splenectomy. Previous studies have shown that HD patients given polyvalent pneumococcal polysaccharide (PPS) vaccine after immunosuppressive therapy have a suboptimum antibody response. This study shows significant antibody response in HD patients to PPS vaccine given before radiation and chemotherapy. The same response was obtained whether the vaccine was given before or after splenectomy.

To assess the immunologic status of healthy persons with hemophilia A, we performed studies of T cell immunity in 21 patients, 10 given only cryoprecipitate and 11 given factor VIII concentrate. Patients in the factor VIII group had significantly decreased helper/suppressor T cell ratios. Both groups had diminished mononuclear cell response to phytohemagglutinin and normal mixed lymphocyte culture, compared with controls. Abnormalities in T cell number or function did not correlate with the presence of antibody to cytomegalovirus, Epstein-Barr virus, or hepatitis B. Physicians caring for patients with hemophilia A should realize that asymptomatic individuals may have early evidence of immunodeficiency.