Kouichi Utsumi

Crossed Cerebellar Diaschisis in Patients With Cortical Infarction Logistic Regression Analysis to Control for Confounding Effects

Background and Purpose— Crossed cerebellar diaschisis (CCD) refers to reduced metabolism and blood flow in the cerebellar hemisphere contralateral to a cerebral lesion. Many cortical areas have been reported to cause CCD without consideration of confounding factors. We performed single-photon emission computed tomography (SPECT) in patients with cortical infarction to identify regions independently related to CCD, controlling for possible confounding effects. Methods— Patients with unilateral cortical infarction (n=113; 75 male, 38 female; mean±SD age, 66±13 years) underwent SPECT of the brain with N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). Regional cerebral blood flow was measured autoradiographically. Asymmetry indices (AIs) were calculated on the basis of ratios representing symmetrical regional cerebral blood flow in the cerebellum and 16 cerebral regions. CCD was defined as AI for cerebellum >0.1. AIs for 16 cortical regions were considered for both dichotomous and continuous variables for analysis of CCD occurrence by means of backward logistic regression. Results— For dichotomized variables, hypoperfusion of postcentral (odds ratio [OR]=7.607; 95% CI, 2.299 to 25.174) and supramarginal (OR=3.916; 95% CI, 1.394 to 11.003) regions independently influenced CCD. For continuous variables, hypoperfusion of postcentral (OR=1.044; 95% CI, 1.019 to 1.068) and supramarginal (OR=1.021; 95% CI, 1.001 to 1.041) regions (and, as a negative factor, medial occipital regions; OR=0.942; 95% CI, 0.895 to 0.991) independently influenced CCD. Conclusions— Many cortical areas apparently do not contribute to CCD. Correspondence of CCD between dichotomized and continuous analyses suggests that location of a lesion, not severity, is the main determinant of CCD.

FABRY DISEASE IN PATIENTS RECEIVING MAINTENANCE DIALYSIS

AbstractBackground. Fabry disease is an X-linked disorder resulting from a deficiency of lysosomal α-galactosidase. Renal insufficiency is one of its most important manifestations and affects the prognosis of the disease. We clarified the incidence of Fabry disease in patients receiving maintenance dialysis. Methods. We measured plasma α-galactosidase activity in 722 patients (male 440, female 282) receiving maintenance dialysis. Clinical manifestations were assessed, and the patients were to be screened for mutations in the α-galactosidase gene. Results. Two male patients had low plasma α-galactosidase activity. One patient had a C-to-T transition at codon 357, resulting in substitution of the predictable termination for glutamine. The other patient died suddenly during hemodialysis, due to arrhythmia. We could not carry out further evaluation, but his daughter had moderate reduction of α-galactosidase activity in leukocytes. She was, likely, an asymptomatic heterozygote. Conclusions. Two male patients with Fabry disease were found among 440 male patients who were receiving maintenance dialysis. Fabry disease should be considered in the etiology of end-stage renal failure.

Characterization of two α-galactosidase mutants (Q279E and R301Q) found in an atypical variant of Fabry disease

The mutant products Q279E ((279)Gln to Glu) and R301Q ((301)Arg to Gln) of the X-chromosomal inherited alpha-galactosidase (EC 3.2.1. 22) gene, found in unrelated male patients with variant Fabry disease (late-onset cardiac form) were characterized. In contrast to patients with classic Fabry disease, who have no detectable alpha-galactosidase activity, atypical variants have residual enzyme activity. First, the properties of insect cell-derived recombinant enzymes were studied. The K(m) and V(max) values of Q279E, R301Q, and wild-type alpha-galactosidase toward an artificial substrate, 4-methylumbelliferyl-alpha-D-galactopyranoside, were almost the same. In order to mimic intralysosomal conditions, the degradation of the natural substrate, globotriaosylceramide, by the alpha-galactosidases was analyzed in a detergent-free-liposomal system, in the presence of sphingolipid activator protein B (SAP-B, saposin B). Kinetic analysis revealed that there was no difference in the degradative activity between the mutants and wild-type alpha-galactosidase activity toward the natural substrate. Then, immunotitration studies were carried out to determine the amounts of the mutant gene products naturally occurring in cells. Cultured lymphoblasts, L-57 (Q279E) and L-148 (R301Q), from patients with variant Fabry disease, and L-20 (wild-type) from a normal subject were used. The 50% precipitation doses were 7% (L-57) and 10% (L-148) of that for normal lymphoblast L-20, respectively. The residual alpha-galactosidase activity was 3 and 5% of the normal level in L-57 and L-148, respectively. The quantities of immuno cross-reacting materials roughly correlated with the residual alpha-galactosidase activities in lymphoblast cells from the patients. Compared to normal control cells, fibroblast cells from a patient with variant Fabry disease, Q279E mutation, secreted only small amounts of alpha-galactosidase activity even in the presence of 10 mM NH(4)Cl. It is concluded that Q279E and R301Q substitutions do not significantly affect the enzymatic activity, but the mutant protein levels are decreased presumably in the ER of the cells.

Severe thiamine deficiency resulted in Wernicke's encephalopathy in a chronic dialysis patient

A 64-year-old male patient with diabetic nephropathy had been treated with maintenance hemodialysis therapy for 4 years, and had developed disturbed consciousness. The disturbance was firstly noticed by a primary care doctor who recognized slow responses in conversation. Prior to developing this symptom, the patient had noticed a loss of appetite for about 2 weeks. During a period of observation at an outpatient clinic, the symptoms became worse. He was admitted to a primary care hospital for 10 days, but his consciousness level deteriorated and he became unconscious (JCS 200). About 1 month after the onset of symptoms, the patient was transferred to our hospital. A brain computed tomography (CT) scan and magnetic resonance imaging (MRI) showed typical abnormal lesions in the aquaduct of the midbrain and thalamus, and a diagnosis of Wernickes encephalopathy was made. In addition, the patients serum thiamine level was extremely low (7 ng/ml). He received immediate treatment with intravenous thiamine administration (150 mg/day), and this significantly improved his symptoms (JCS 2). Dialysis patients may develop water-soluble vitamin deficiency as a result of the combination of reduced oral intake and increased loss of vitamins into the dialysate. Wernickes encephalopathy should be considered as one of many causes of disturbed consciousness in hemodialysis patients. A rapid diagnosis and adequate treatment are essential in order to minimize long-term neurological sequelae.

Renal thrombotic microangiopathy associated with chronic graft‐versus‐host disease after allogeneic hematopoietic stem cell transplantation

Thrombotic microangiopathy (TMA) is a major complication after hematopoietic stem cell transplantation (HSCT). In this study, we examined the clinical and pathologic features of 2 patients and 5 autopsy cases with HSCT‐associated renal TMA to clarify the association between graft‐versus‐host disease (GVHD) and renal TMA. The median interval between HSCT and renal biopsy or autopsy was 7 months (range 3–42 months). Clinically, acute and chronic GVHD occurred in 7 and 4 patients, respectively. Clinical evidence for TMA was detected in 2 patients, while chronic kidney disease developed in all patients. The main histopathological findings were diffuse endothelial injury in glomeruli, peritubular capillaries (PTCs), and small arteries. In addition, all cases showed glomerulitis, renal tubulitis, and peritubular capillaritis with infiltration of CD3+ T cells and TIA‐1+ cytotoxic cells, suggesting that GVHD occurred during the development of TMA. Diffuse and patchy C4d deposition was noted in glomerular capillaries and PTCs, respectively, in 2 biopsy and 2 autopsy cases, suggesting the involvement of antibody‐mediated renal endothelial injury in more than 50% of renal TMA cases. In conclusion, the kidney is a potential target of chronic GVHD that may induce the development of HSCT‐associated TMA. Importantly, some cases are associated with chronic humoral GVHD.

Renal thrombotic microangiopathy associated with chronic humoral graft versus host disease after hematopoietic stem cell transplantation

Thrombotic microangiopathy (TMA) is a known complication of hematopoietic stem cell transplantation (HSCT). The pathogenesis of TMA is controversial but considered to involve various factors such as total body irradiation, use of calcineurin inhibitors for prophylaxis against graft versus host disease (GVHD), viral infection, and GVHD. Herein we describe a case with renal TMA after HSCT, which was probably associated with antibody‐mediated endothelial cell injury from chronic GVHD (termed here ‘chronic humoral GVHD’). A 49‐year‐old man presented two years after HSCT with renal dysfunction and proteinuria but without the clinical features of TMA. Histopathological examination of renal biopsy showed chronic glomerular endothelial cell injury with double contour of the glomerular basement membrane, microthrombi and the deposition of complement split product C4d along the glomerular capillaries. Renal tubulitis and peritubular capillaritis were also noted with a multilayered basement membrane and patchy C4d deposition on peritubular capillaries. These findings resemble those of chronic antibody‐mediated rejection after kidney transplantation. Furthermore, C4d deposition suggests complement activation. Although circulating anti‐blood type and anti‐human leukocyte antigen antibodies were not detected, the renal TMA in this case was probably associated with chronic humoral GVHD.

GM2 GANGLIOSIDOSIS AB VARIANT: CLINICAL AND BIOCHEMICAL STUDIES OF A JAPANESE PATIENT

Objective: To determine the clinical features and biochemical basis of the first Japanese patient with the GM2 gangliosidosis AB variant. Methods: The clinical manifestations and laboratory findings in the patient were investigated. Cultured fibroblasts from the patient were analyzed by means of immunofluorescence staining with an anti-GM2 ganglioside monoclonal antibody and thin-layer chromatography and immunostaining. GM1 ganglioside catabolism in cultured cells was analyzed by pulse labeling, and the amount of GM2 activator in cells was determined by Western blot analysis. Gene analysis was performed according to standard protocols. Results: The patient showed progressive neurologic manifestations of quite early onset. Muscular weakness and hypotonia became evident by 1 month of age, and the patient then developed a startle reaction, severe psychomotor retardation, and myoclonic seizures. Immunocytochemical analysis clearly revealed the accumulation of GM2 ganglioside in cultured fibroblasts from the patient, and thin-layer chromatography confirmed it. Western blot and metabolic studies showed a complete deficiency of GM2 activator. Gene analysis did not reveal any mutations in the protein coding region of the GM2 activator gene. Conclusion: The clinical features and biochemical basis of this Japanese patient with GM2 gangliosidosis AB variant were determined. Immunocytochemical analysis using cultured fibroblasts as samples is available for the diagnosis of this disease.

Urinary excretion of the vitronectin receptor (integrin αVβ3) in patients with Fabry disease

Abstract A renal disorder is one of the important manifestations of Fabry disease, but the details of the pathogenesis have not been clarified yet. We examined the possibility that the vitronectin receptor (VNR, integrin α V β 3 ), one of the integrins, is involved in the progression of the renal injury in Fabry disease. We measured the urinary excretion of β 3 originating from VNR in Fabry patients by immunoblotting analysis and enzyme-linked immunosorbent assay (ELISA). Immunofluorescent microscopic analyses for VNR and globotriaosylceramide were performed on urinary sediments from Fabry patients. Furthermore, β 3 and vitronectin in kidney tissues were analyzed immunohistochemically. Immunoblotting analysis and ELISA showed that the urinary excretion of β 3 originating from VNR was significantly increased in the Fabry group compared with both the pathological and healthy control groups. Immunofluorescent microscopy revealed the expression of VNR and accumulation of globotriaosylceramide in urinary sediments from the Fabry patients. Increased expression of β 3 was observed in glomerular epithelial cells, and in Bowmans capsular epithelial layer and tubular cells, and the amount of vitronectin was moderately increased in the kidney tissues from the Fabry patients. The urinary excretion of VNR was increased, and the expression of VNR was observed in Fabry kidney tissues. The expression of VNR may be involved in the progression of the renal injury in this disease.

Immunohistochemical characterization of transgenic mice highly expressing human lysosomal α-galactosidase

Human lysosomal alpha-galactosidase predominantly hydrolyzes ceramide trihexoside. A transgenic mouse line, C57BL/6CrSIc-TgN(GLA) 1951 Rin, highly expressing human alpha-galactosidase, has been established and investigated biochemically and immunohistochemically in order to clarify the distribution of the expressed enzyme proteins and to evaluate it as a donor model of organ transplantation therapy for Fabry disease caused by a genetic defect of alpha-galactosidase. In these transgenic mice, about five copies of the transgene were integrated, and alpha-galactosidase activity was expressed in liver, kidney, heart, spleen, small intestine, submaxillary gland, skeletal muscle, cerebrum, cerebellum, bone marrow cells and serum. The enzyme activity was about 22 to 11,080-fold higher than that in non-transgenic mice. In liver, heart and kidney tissues, which are important organs for transplantation studies, sufficient amounts of alpha-galactosidase mRNAs were transcribed, and the expressed enzymes, with molecular weights of 54-60 kDa, are abundant in the liver (enzyme activity: 53,965 nmol h-1 mg-1 protein) and heart (39,906 nmol h-1 mg-1 protein), followed by in the kidney tissue (9177 nmol h-1 mg-1 protein), respectively. An immunohistochemical microscopic study clearly demonstrated the distribution of the expressed enzyme proteins in kidney and liver tissues. Highly expressed alpha-galactosidase was detected in glomerular cells, tubular cells and hepatocytes. These transgenic mice will be useful as a donor model for experimental organ transplantation, and also it will enable recurrent biopsies and long-term observation. The organ transplantation data on mice will provide us with important information.

Factors influencing outcome in Guillain–Barré Syndrome: comparison of plasma adsorption against other treatments

OBJECTIVE This study was performed to evaluate which factors influence the outcome of Guillain-Barré Syndrome (GBS), focusing on the choice of treatments. METHODS Sixty-three GBS patients were retrospectively studied and the following factors were evaluated: sex, age, days from onset of disease to the start of treatment, severity of symptoms, prior infection, autonomic dysfunction, bulbar palsy, anti-ganglioside antibody, and disease form, as well as the choice of treatment. Plasma adsorption (PA, n=39), plasma exchange (PE, n=14), or immunoglobulin treatment (IVIg, n=10) were performed in this study. Outcomes were evaluated using the functional grading scale (FGS) of Hughes. RESULTS The number of days needed for one functional grade improvement was significantly longer in the elderly, the severe symptom group, and patients with acute motor axonal form, and days needed for two functional grade improvement was significantly longer in the elderly, patients with autonomic dysfunction, and acute motor axonal form. The choice of treatments (PA, PE, or IVIg) did not significantly influence the outcome as determined by both univariate and multivariate analysis. CONCLUSION Although patient age, symptoms, and disease form influenced the outcome, treatment methods did not significantly influence the outcome. Since PA does not result in a risk of unknown infection, choosing a PA treatment may be justified, especially for patients (or doctors) who may be anxious about a possibility of unknown infection.