Diagnostic criteria for atypical hemolytic uremic syndrome proposed by the joint committee of the Japanese society of nephrology and the Japan pediatric society

Atypical hemolytic uremic syndrome (aHUS) is rare and comprises the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Recently, abnormalities in the mechanisms underlying complement regulation have been focused upon as causes of aHUS. The prognosis for patients who present with aHUS is very poor, with the first aHUS attack being associated with a mortality rate of ~25 %, and with ~50 % of cases resulting in end-stage renal disease requiring dialysis. If treatment is delayed, there is a high risk of this syndrome progressing to renal failure. Therefore, we have developed diagnostic criteria for aHUS to enable its early diagnosis and to facilitate the timely initiation of appropriate treatment. We hope these diagnostic criteria will be disseminated to as many clinicians as possible and that they will be used widely.     

Narrow band imaging-guided endoscopic biopsy for intraventricular and paraventricular brain tumors: clinical experience with 14 cases

Background

Narrow-band imaging (NBI) has been confirmed as a useful endoscopic technique to distinguish neoplasm from normal tissue, on the basis of the enhanced neovascularity of tumor tissue. NBI-guided tissue biopsy for laryngopharyngeal and digestive lesions is a novel methodology, but the feasibility for central nervous system tumors remains unclear. The aim of our study was to evaluate the feasibility of NBI-guided biopsy for intraventricular and paraventricular tumor.

Methods

Fourteen patients with intraventricular or paraventricular tumors underwent neuroendoscopic biopsy using a videoscope with NBI. Ventricular walls and tumors were observed using conventional imaging, followed by NBI. Colors of ventricle walls and tumors visualized using NBI were compared to those visualized under conventional imaging. Extracted specimens were stained using CD31 antibody and numbers of microvessels in each specimen were counted for analyzing vascular density.

Results

Normal ventricle walls were a similar color under conventional imaging and NBI. Tumor surfaces appeared to be cyan in color under NBI. Vessels on the tumor were more clearly visualized with NBI than with conventional imaging. NBI was able to identify tumor surfaces that were not perceptible on conventional imaging. All specimens in the lesion surfaces from cyan-colored areas under NBI contained tumor cells. Specimens extracted from regions that appeared cyan in color under NBI (51.0 vessels/mm²) had significantly greater vascular density than regions that appeared a normal color (17.4 vessels/mm²; p = 0.039).

Conclusion

NBI-guided biopsy of intraventricular and paraventricular tumors is feasible for visualizing tumor surface-enhancing neovascularities. NBI would contribute to accurate histological diagnosis while minimizing injury to surrounding structures.     

Risk Factors of Cytomegalovirus Infection After Pediatric Liver Transplantation

PurposeCytomegalovirus (CMV) infection is known to be the most frequently viral infection among patients after liver transplantation. This is especially true in pediatric living-donor liver transplantation because the recipients have often not been infected with CMV and postoperative primary infection with CMV frequently occurs.Patients and MethodsOf 93 patients who underwent pediatric liver transplantation at our department, 33 patients (36.3%) were diagnosed with CMV infection using the antigenemia method (C7-HRP). Retrospective review and statistical analysis were conducted to confirm risk factors of post-transplantation CMV infection.ResultPositive lymphocytes were diagnosed between postoperative days 8 and 111 after transplantation. Ganciclovir or foscavir were administrated to 21 patients. The other 10 patients who had one positive lymphocyte were observed and the cell disappeared on follow-up examination. We did not observe any cases of positive lymphocytes with C7-HRP in patients who received a graft from a CMV antibody?negative donor. Independent predictors associated with CMV infection in the multivariable analysis were administration of OKT3 and grafts from CMV antibody?positive donors.ConclusionIn CMV infection after pediatric liver transplantation, cases with CMV antibody?positive donors and with OKT3 administration for acute rejection are considered high risk, and cases with CMV antibody?negative donors are considered low risk.