Vol 15, No 2 (2016)

Vasculites associated with anti-neutrophil cytoplasmic antibodies (ANCA) (further AAV) include granulomatosis with polyangiitis (previously Wegener disease, now GPA ), microscopic polyangiitis (MP), eosinophilic granulomatosis with polyangiitis (EGPA, previously Churg-Strauss syndrome) and diseases of particular organs, such as renal vasculitis. Though rarely, AAV occurs in children and is accompanied by severe manifestations and mortality, especially in late diagnosis of disease. In most cases, AAV are associated with serologically detected ANCA. Antibodies (ANCA) directed against proteinase-3 (PR3) or myeloperoxidase (MPO) of neutrophils are associated with GPA or MP in more than 80% of cases. And vice versa, only 50% of patients with EGPA are ANCA-positive; and if ANCA are present, in 75% of cases they are directed against MPO. The use of regimens with cyclophosphamide (CP) and high doses of corticosteroids (CS) for remission induction in the past 25 years have transferred AAV from the category of lethal to chronically recurrent diseases. Research in reduction of cyclophosphamide toxicity have resulted in development of safer immunosuppressants for supportive therapy, such as methotrexate (MT) or azathioprine (AZA). Later, stratification of AAV by severity has singled out patients with mild and moderate courses of disease, who are treated according to protocols that do not include CP. Since 2011, rituximab, a monoclonal anti-CD-20 antibody, has been introduced as the first-line AAV therapy. The article discusses current tactics of management of ANCA-vasculites in adults and children.

Presence of central vein catheter (CVC) is well known as a risk factor for deep vein thrombosis (DVT) incidence especially in patients with malignancies. The term «CVC-related thrombosis»is attributed to mural thrombosis that involves CVC and adheres to vessel wall. However, presence of CVC in a central vein may result in emerging not only «true»mural thrombosis but so-called^_ fibrin sheaths (FS) that envelope CVC but do not involve venous wall. Despite high FS incidence data on its clinical importance are scarce. We investigate FS significance for subsequent DVT appearance. Patients and methods. We analyzed data on 182 CVC inserted in 113 patients aged from 1 to 19 years suffering from ALL. Data were collected retrospectively from electronic hospital charts. The diagnosis of DVT and FS was made by means of echocardiography (ECHO) and Doppler ultrasound scanning (DUS) of brachiocephalic veins. DUS has been performed at different time after CVC implantation depending on clinical indications and physician's opinion. Results. Incidence of FS was 2,71 events per 1000 catheter days. Presence of FS was significantly associated with DVT incidence (odds ratio (OR) 2,75, 95% confidential interval (CI) 1,32-5,74, р = 0,003). FS resolution occurred independently of anticoagulant usage (р = 0,598). Difference in DVT incidence between groups with and without anticoagulant prophylaxis after FS detecting was statistically insignificant (р = 0,908). Discussion. According to our data, FS were detected on 35% of CVC. Presence of FS was associated with CVC-related DVT incidence. Efficiency of anticoagulants for FS resolving is doubtful. The question whether anticoagulant prophylaxis of DVT should be started after FS detecting remains open. Large prospective studies are required to resolve this issue.

Assessment of the effectiveness of platelet concentrate transfusion after hematopoietic stem cell transplantation is based on calculation of the amount of platelets and does not take into account their functional activity. The article offers an integral study of the state of hemostasis in 10 children (aged 3 to 16 years, median 11 years) before and after platelet concentrate transfusion with the use of tests for assessment of platelet functional activity and thrombin generation in space (thrombodynamics-4D). Two hours after platelet concentrate transfusion the amount of platelet increased from 8.0 ± 6.6 to 52.3 ± 25.2 X 10⁹/L. Secretion of platelet dense granules (1.37 ± 0.48, norm 3.52 ± 1.14 units) and a-granules (5969 ± 2366, norm 11787 ± 4639 units), activated (385 ± 167, norm 1279 ± 682 units) and non-activated glycoprotein IIb/IIIa (3179 ± 1609, norm 5557 ± 2017 units) before transfusion was lower as compared with values of healthy volunteers and did not change after transfusion. A characteristic for healthy volunteers «thrombin wave» in studying thrombodynamics-4D was not formed in samples of patients both before and after transfusion. After platelet concentrate transfusion, an increase of the clot growth rate from 25 ± 8 to 32 ± 4 pm/min (p < 0.005) and thrombin reaction product from 124 ± 49 to 209 ± 38 pM*mm was observed (p < 0.001). The increased amounts of thrombin are indicative of improvement of blood coagulation after platelet concentrate transfusion, but parameters of platelet functional activity and thrombodynamics-4D do not reach normal values.