title: [Shear stress-induced platelet aggregation in children with minimal change nephrotic syndrome].
abstract: Analysis of the hemostasis system using biochemical techniques in children with minimal change nephrotic syndrome (MCNS) has previously been restricted to in vitro assays. The recent introduction of measurement of shear stress-induced platelet aggregation (SIPA) using platelet-rich plasma (PRP) has facilitated detailed investigation of the hemostatic system in vivo. In order to further analyze the etiology of the thrombotic tendency exhibited by patients with childhood MCNS, we investigated SIPA at both low shear stress (L-SIPA) and high shear stress (H-SIPA) in 14 children with MCNS using PRP collected weekly after commencing prednisolone therapy. Seven patients were newly diagnosed cases of MCNS (ND) whereas the remainder had suffered a disease relapse (DR). Prior to prednisolone therapy L-SIPA, which was thought to be affected by fibrinogen (Fbg) levels, was significantly increased in both patient groups compared to normal controls (17.4 +/- 4.1% vs. 3.6 +/- 0.7%, ND vs control, p < 0.01: 11.7 +/- 3% vs. 2 +/- 0.7%, DR vs control, p < 0.01) with values declining at weekly intervals thereafter. Plasma Fbg levels in simultaneously collected samples followed a similar course. In contrast, H-SIPA, which was thought to be affected by von Willebrand factor (VWF), was significantly enhanced in MCNS patients after 1 week of prednisolone therapy compared to the controls (45 +/- 5.1% vs. 26.3 +/- 3.5%, ND vs normal, p < 0.05: 36.9 +/- 3.3% vs. 25.5 +/- 1.6%, DR vs. normal, p < 0.05). Plasma ristocetin cofactor and VWF antigen levels in simultaneously collected samples followed a similar course, whereas thrombin-antithrombin complex (TAT) levels remained constant. These results indicate that SIPA is enhanced in the acute stage of childhood MCNS, especially L-SIPA prior to the initiation of prednisolone therapy and H-SIPA after 1 week of prednisolone therapy, and that these phenomena may be affected by plasma Fbg and VWF levels, respectively. The enhanced SIPA may play an important thrombogenic role in the acute phase of childhood MCNS.
authors.affiliation: Department of Pediatrics, Nara Medical University, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Takagawa
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Nakajima
authors.forename: Koji
authors.initials: K
authors.lastname: Taira
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Sakagami
authors.forename: Taku
authors.initials: T
authors.lastname: Ueda
authors.forename: Hideki
authors.initials: H
authors.lastname: Akazawa
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Maruhashi
authors.forename: Hironobu
authors.initials: H
authors.lastname: Shimoyama
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Fujimura
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Kamitsuji
authors.forename: Akira
authors.initials: A
authors.lastname: Yoshioka
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D009402:Nephrosis, Lipoid / Q000097:blood* / Q000188:drug therapy; D010974:Platelet Aggregation / Q000502:physiology*; D011239:Prednisolone / Q000627:therapeutic use; D013314:Stress, Mechanical; D014841:von Willebrand Factor / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor; D011239:Prednisolone