Urinary liver-type fatty acid-binding protein in pediatric nephrotic syndrome and tubular dysfunction.

BACKGROUND: Urinary liver-type fatty acid-binding protein (uL-FABP) has recently been identified as a biomarker for kidney injury. uL-FABP excretion in pediatric relapsing nephrotic syndrome and tubular dysfunction, however, has not been reported previously. METHODS: We measured uL-FABP level in children with steroid-sensitive nephrotic syndrome (SSNS), in those with tubular dysfunction, and in control subjects. RESULTS: uL-FABP was markedly increased in relapsing SSNS (median, 30.3 µg/gCr; range, 12.6-171.0 µg/gCr; n = 13), and also in the tubular dysfunction group (median, 164.8 µg/gCr; range, 41.6-834.5 µg/gCr; n = 7), compared with the control subjects (median, 3.0 µg/gCr; range, 1.1-13.9 µg/gCr; n = 21). uL-FABP level was significantly correlated with urinary protein excretion in the SSNS group, and in the total group. Additionally, in the SSNS group, elevated uL-FABP in the relapsing stage returned to a level similar to that in the control group on remission of NS. In the tubular dysfunction group, uL-FABP was significantly correlated with urinary ß2-microglobulin. CONCLUSION: Urinary protein amount, and the ability of the proximal tubules to reabsorb low-molecular-weight proteins, should also be considered when evaluating the clinical significance of uL-FABP as a biomarker for kidney injury in children.

Health-care transition after Kawasaki disease in patients with coronary artery lesion.

BACKGROUND: Discussion of health-care transition (HCT) for adults with a childhood history of coronary artery lesions (CAL) after Kawasaki disease (KD) is important. A nationwide questionnaire survey was performed with support by the Japanese Society of Kawasaki Disease. The purpose of this study was to clarify the reality of HCT and loss to follow-up in patients with CAL after KD. METHODS: The survey was emailed to 48 members of the Japanese Society of Kawasaki Disease from May to July 2014. RESULTS: Forty surveys were collected, giving a response rate of 83.3%. Sixty-five percent of the respondents belonged to a university hospital. Approximately 90% of the respondents dealt with patients who needed HCT, and 55% had patients who completed HCT. Approximately 70% of the respondents considered that pediatricians should continue sharing HCT information with cardiologists. More than 95% of the respondents had a favorable or average impression of HCT care provided by cardiologists. The percentage of respondents who had loss to follow up for HCT was >40%. CONCLUSION: Adult cardiologists began managing patients with CAL after KD in more than half of the institutes in this study. Pediatricians should construct a support program for better management of these patients and for cooperation with cardiologists to prevent loss to follow up.

Non-receptor type, proline-rich protein tyrosine kinase 2 (Pyk2) is a possible therapeutic target for Kawasaki disease.

Kawasaki disease (KD) is a paediatric vasculitis whose pathogenesis remains unclear. Based on experimental studies using a mouse model for KD, we report here that proline-rich protein tyrosine kinase 2 (Pyk2) plays a critical role in the onset of KD-like murine vasculitis. The mouse model for KD was prepared by administrating a Candida albicans water-soluble fraction (CAWS). Unlike CAWS-treated WT mice, CAWS-treated Pyk2-Knockout (Pyk2-KO) mice did not develop apparent vasculitis. A sustained increase in MIG/CXCL9 and IP-10/CXCL10, both of which have potent angiostatic activity, was observed in CAWS-treated Pyk2-KO mice. CAWS-induced activation of STAT3, which negatively regulates the expression of these chemokines, was also attenuated in macrophages derived from Pyk2-KO mice. The present study suggests that defects in Pyk2 suppress KD-like experimental vasculitis, presumably through CXCL9- and CXCL10-dependent interference with neo-angiogenesis. Since Pyk2-KO mice show no life-threatening phenotype, Pyk2 may be a promising therapeutic molecular target for KD.

Oxidative stress and Kawasaki disease: how is oxidative stress involved from the acute stage to the chronic stage?

Inflammation and oxidative stress are closely related. Further, oxidative stress plays an important role in the pathology of inflammation-based Kawasaki disease. An excessive in vivo production of reactive oxygen species increases oxidative stress in the body, which triggers an endless vicious spiral of inflammation reactions and reactive oxygen metabolites. This presumably forms diffuse vasculitis in the acute phase. Acute inflammation and oxidative stress can be rapidly controlled by treatments; however, they may remain for a long time. This has recently been identified as a problem in the chronic phase of Kawasaki disease. Generally, the presence of vascular inflammation and oxidative stress impairs blood vessels, leading to the onset of atherosclerosis, which is a widely recognized risk. The current discussion focuses on whether the same is valid for blood vessels in the chronic phase of Kawasaki disease.

Nationwide Survey of Patients With Giant Coronary Aneurysm Secondary to Kawasaki Disease 1999-2010 in Japan.

BACKGROUND: Giant coronary aneurysm is the most severe sequela in Kawasaki disease, occurring in approximately 0.2% of patients in Japan. Regression is rare, while myocardial infarction (MI) and sudden death are relatively common. Herein, we reviewed patients with giant coronary aneurysm in a 10-year period.Methods and Results:A nationwide questionnaire survey was conducted based on a national epidemiological database from 1999 to 2010. We identified 355 giant coronary aneurysm patients, of whom 209 were analyzed. The 5- and 10-year total cardiac event-free rates were 0.72 and 0.68, respectively. Twelve patients died, and MI was observed in 32 patients (18.1%). Five and 6 deaths were due to coronary rupture and MI, respectively. All ruptures occurred within 1 month of onset, while most MI occurred within 18 months. There was no death beyond 2 years. Aneurysm size was significantly related to the occurrence of MI in both the right and left coronary arteries. At the time of writing, 55% of patients had no exercise limitations. And including patients who cannot perform strenuous exercises, 81% of patients were leading ordinary lives. CONCLUSIONS: Severe cardiac events are likely to occur within 2 years from onset of Kawasaki disease, while no deaths occurred beyond this time. Hence, careful monitoring is needed especially for the first 2 years. Most patients with giant coronary aneurysms can lead ordinary lives with appropriate management.

The Application of a Modified d-ROMs Test for Measurement of Oxidative Stress and Oxidized High-Density Lipoprotein.

Reactive oxygen species (ROS) are involved in the initiation and progression of atherosclerosis. ROS-derived hydroperoxides, as an indicator of ROS production, have been measured by using the diacron reactive oxygen metabolites (d-ROMs) test, which requires iron-containing transferrin in the reaction mixture. In this study we developed a modified d-ROMs test, termed the Fe-ROMs test, where iron ions were exogenously added to the reaction mixture. This modification is expected to exclude the assay variation that comes from different blood iron levels in individuals. In addition, this Fe-ROMs test was helpful for determining the class of plasma lipoproteins that are hydroperoxidized. Low-density lipoprotein/very low-density lipoprotein (LDL/VLDL) and high-density lipoprotein (HDL) were purified by use of an LDL/VLDL purification kit and the dextran sulfate-Mg2+ precipitation method, respectively; their hydroperoxide contents were assessed by performing the Fe-ROMs test. The majority of the hydroperoxides were detected only in the HDL fraction, not in the LDL/VLDL. Further detailed analysis of HDLs by size-exclusion high-performance liquid chromatography revealed that the hydroperoxide-containing molecules were small-sized HDLs. Because HDL was shown to be the principal vehicle for the plasma hydroperoxides, this Fe-ROMs test is a beneficial method for the assessment of oxidized-HDL levels. Indeed, Fe-ROMs levels were strongly associated with the levels of oxidized HDL, which were determined by performing the malondialdehyde-modified HDL enzyme immunoassay. In conclusion, the Fe-ROMs test using plasma itself or the HDL fraction after dextran sulfate-Mg2+ precipitation is useful to assess the functionality of HDL, because the oxidation of HDL impairs its antiatherogenic capacity.

Genetic mutation analysis in Japanese patients with non-syndromic congenital heart disease.

Congenital heart disease (CHD) is the most common birth defect occurring in humans and some transcriptional factors have been identified as causative. However, additional mutation analysis of these genes is necessary to develop effective diagnostic and medical treatment methods. We conducted sequence analysis of the coding regions of NKX2.5, GATA4, TBX1, TBX5, TBX20, CFC1 and ZIC3 in 111 Japanese patients with non-syndromic CHD and 9 of their relatives. All patient samples were also analyzed by multiplex ligation-dependent probe amplification using probes involved in chromosome deletion related to CHD. Five novel variations of TBX5, GATA4 and TBX20 were detected in 6 of the patients, whereas none were found in 200 controls. The TBX5 variation p.Pro108Thr, located in the T-box domain, was identified in a patient with tricuspid atresia, an exon-intron boundary variation of GATA4 (IVS4+5G>A) was detected in a Tetralogy of Fallot patient and an 8p23 microdeletion was detected in one patient with atrioventricular septal defect and psychomotor delay. A total of seven non-synonymous polymorphisms were found in the patients and controls. Accumulation of novel variations of genes involving the cardiac development may be required for better understanding of CHD.

Transcriptional Analysis of Intravenous Immunoglobulin Resistance in Kawasaki Disease Using an Induced Pluripotent Stem Cell Disease Model.

BACKGROUND: Approximately 10-20% of Kawasaki disease (KD) patients are resistant to intravenous immunoglobulin (IVIG) treatment. Further, these patients are at a particularly high risk of having coronary artery abnormalities. The mechanisms of IVIG resistance in KD have been analyzed using patient leukocytes, but not patient vascular endothelial cells (ECs). The present study clarifies the mechanisms of IVIG resistance in KD using an induced pluripotent stem cell (iPSC) disease model.Methods and Results:Dermal fibroblasts or peripheral blood mononuclear cells from 2 IVIG-resistant and 2 IVIG-responsive KD patients were reprogrammed by the episomal vector-mediated transduction of 6 reprogramming factors. KD patient-derived iPSCs were differentiated into ECs (iPSC-ECs). The gene expression profiles of iPSC-ECs generated from IVIG-resistant and IVIG-responsive KD patients were compared by RNA-sequencing analyses. We found that the expression ofCXCL12was significantly upregulated in iPSC-ECs from IVIG-resistant KD patients. Additionally, Gene Set Enrichment Analysis (GSEA) revealed that gene sets involved in interleukin (IL)-6 signaling were also upregulated. CONCLUSIONS: The first iPSC-based model for KD is reported here. Our mechanistic analyses suggest thatCXCL12, which plays a role in leukocyte transmigration, is a key molecule candidate for IVIG resistance and KD severity. They also indicate that an upregulation of IL-6-related genes may be involved in this pathogenesis.

Tolerance to ischemia reperfusion injury in a congenital heart disease model.

BACKGROUND: Open heart surgery-associated ischemia/reperfusion (I/R) injury affects postoperative outcome, and a leading cause of this is lipid peroxidation. Congenital heart disease (CHD) patients, however, are less sensitive to I/R injury. Although little is known about the underlying molecular mechanisms, CHD-associated hypoxia alters the polyunsaturated fatty acid (PUFA) composition of membranes, which are the preferential targets for reactive oxygen species (ROS) generated during I/R. Here, using an animal model, we investigated the molecular mechanisms underlying I/R tolerance in CHD. METHODS: In order to reproduce I/R injury in vitro, we used a working heart perfusion model, isolated from juvenile control and CHD model rats (CHD rats), and examined the recovery of cardiac function during a period of I/R. PUFA composition of the plasma membrane was determined on gas chromatography/mass spectrometry. Oxidative stress-related cellular responses were investigated on immunoblotting, using antibodies against nuclear factor erythroid 2-related factor (Nrf-2), hemeoxygenase-1 (HO-1), and 4-hydroxy-2-hexanal (4-HHE)-modified protein. RESULTS: Ischemia/reperfusion-induced cardiac dysfunction was markedly suppressed in CHD rats, compared with the control rats. n-3/n-6 PUFA ratio was significantly increased in both the pre- and post-I/R phase in CHD rats, but not in the controls. Four-HHE-modified protein, Nrf-2, and HO-1 were significantly increased in CHD rats as well, compared with the controls. CONCLUSIONS: Following open heart surgery in CHD patients, the increased n-3/n-6 PUFA ratio may lead to the upregulation of cellular antioxidative system components through the oxidation product, 4-HHE, resulting in an increased tolerance to I/R injury.

Combined Alport syndrome and Klinefelter syndrome.

To date, there have been a very limited number of case reports on combined Alport syndrome (AS) and Klinefelter syndrome (KS). We herein describe the case of a 9-month-old boy diagnosed with concomitant AS and KS. KS was detected on chromosomal analysis of the amniotic fluid, and hematuria/proteinuria was identified in urinary screening at 6 months of age. Renal biopsy indicated AS, with complete deficit of the α5 chain of type IV collagen in the glomerular basement membranes. On genetic analysis for AS, de novo homozygote mutation (c.3605-2a > c) was seen in the gene encoding α5 chain of type IV collagen (COL4A5) on the X chromosomes of maternal origin. This is the first case report of combined AS and KS diagnosed during infancy, and it indicates the need to consider the concurrent existence of these two disorders in infants with urine abnormalities, even in the absence of a family history.

Asymptomatic spinal arteriovenous fistula presenting only as continuous murmur.

Spinal arteriovenous fistula is extremely rare in children. Weakness and sensory disturbance in the lower extremities are the specific clinical presentations. Children, however, commonly have no subjective symptoms; in rare cases, a continuous murmur is the only physical finding. An 18-month-old boy was referred for evaluation of a continuous murmur audible at the back. He had no motor or sensory disorder; only a Levine 3/6 continuous murmur audible at the back was found. Echocardiography showed a structurally normal heart but indicated ascending continuous blood flow behind the aortic arch and dilatation of the innominate vein. We suspected spinal arteriovenous fistula, and it was visualized on computed tomography angiography. Spinal arteriovenous fistula was detected using only auscultation and echocardiography. Suspicion of this anomaly on careful auscultation and simple examination, and confirmation on detailed examination, even in the absence of motor or sensory disturbance, is important.

IgA nephropathy in a girl with mitochondrial disease.

Mitochondrial renal disease is one of the important causes of end-stage renal disease in children and its incidence may be underestimated. We here describe the case of a 13-year-old girl who was diagnosed with mitochondrial disease (MD) accompanied by IgA nephropathy (IgAN). She presented with persistent proteinuria, short stature, and hearing defect, and her younger sister had the same symptoms. Renal biopsy indicated mild focal segmental mesangial proliferation with dominant mesangial IgA deposition on immunofluorescence. Electron microscopy showed marked proliferation of abnormal mitochondria in the proximal tubular cells. Enzyme activity of the mitochondrial respiratory chain complex I and IV in cultured skin fibroblasts was significantly decreased. This case indicated the possible co-occurrence of IgAN and MD. Underlying MD should be considered in patients with urine abnormalities, especially in those with multiple organ involvement.

Combination of double aortic arch and interruption of aortic arch in pulmonary atresia with ventricular septal defect.

No reports on pulmonary atresia with ventricular septal defect with the combination of double aortic arch and interruption between left and right carotid arteries have been published so far.

Coexisting Membranous Nephropathy and IgA Nephropathy.

We herein present a case of a 14-year-old boy with the histological features of coexisting membranous nephropathy (MN) and IgA nephropathy (IgAN). Asymptomatic hematuria/proteinuria was initially detected in school urinary screening, with treatments including oral corticosteroids leading to complete remission. Cases of coexisting MN and IgAN are very rare among the pediatric population; however, the overlap of these two nephropathies does not always imply a deleterious clinical outcome in pediatric cases.

Involvement of mannose-binding lectin in the pathogenesis of Kawasaki disease-like murine vasculitis.

Kawasaki disease (KD) is a paediatric idiopathic vasculitis. In this study, on the basis of studies using an established animal model for KD, we report that mannose-binding lectin (MBL) is involved in the pathogenesis of the disease. KD-like experimental murine vasculitis was induced by intraperitoneally administering a Candida albicans water-soluble extract (CAWS). MBL-A gradually increased in the serum of the model mice treated with CAWS. Deposition of MBL-A and MBL-C was observed in the aortic root, including the coronary arteries, which is a predilection site in experimental vasculitis. Corresponding to the distribution patterns of MBLs, marked deposition of C3/C3-derived peptides was also observed. Regarding the self-reactivity of MBLs, we observed that MBLs interacted with core histones to activate the lectin pathway. These results suggest that some types of pathogens provoke the MBL-dependent complement pathway (lectin pathway) to cause and/or exacerbate KD-like vasculitis.

A survey of the 3-decade outcome for patients with giant aneurysms caused by Kawasaki disease.

BACKGROUND: Our purpose was to determine the outcome in patients with a more-than-20-year history of giant coronary aneurysms (GAs) caused by Kawasaki disease (KD). METHODS: Between 2010 and 2011, the incidence and outcome of cardiac events (CEs) in patients with GA was surveyed by questionnaire by the Kinki area Society of KD research. Death, acute myocardial infarction (AMI), coronary artery bypass grafting (CABG), percutaneous coronary catheter intervention, syncope, and ventricular tachycardia were considered as CEs. Survival rate and CE-free rate were analyzed by the Kaplan-Meier method. RESULTS: We enrolled 245 patients (187 were male, 58 were female), 141 with bilateral GA and 104 with unilateral GA. The interval between the onset of acute KD to the time of survey ranged from 0.2 to 51 years, and the median was 20 years. Death, AMI, and CABG occurred in 15 (6%), 57 (23%), and 90 patients (37%), respectively. The CE-free rate and the survival rate at 30 years after KD were 36% (95% CI 28-45) and 90% (95% CI 84-94), respectively. The 30-year survival rate for bilateral GA was 87% (95% CI 78-93), and for unilateral GA, it was 96% (95% CI 85-96; hazard ratio 4.60, 95% CI 1.27-29.4, P = .027). The 30-year survival rate in patients with AMI was 49% (95% CI 27-71), and the 25-year survival rate in patients undergoing CABG was 92% (95% CI 81-98). CONCLUSIONS: The outcome differed significantly between bilateral GA and unilateral GA. The results focus attention on the need to preserve myocardial perfusion, especially in high-risk patients with bilateral GA. An understanding of the optimal CABG would be useful in bilateral GA.

A case of Fabry nephropathy with histological features of oligonephropathy.

UNLABELLED: Newborn screening studies indicate the expected high incidence of later-onset Fabry disease with silent Fabry nephropathy while, with recent improved clinical care of premature infants, children with congenital oligonephropathy caused by premature embryonal development of the kidney are thought to be increasing. However, the coexistence of Fabry nephropathy and oligonephropathy has not been reported previously. We present the case of a 13-year-old boy who was diagnosed with Fabry nephropathy accompanied with histological features of oligonephropathy. He was born as a preterm baby, and a renal biopsy was performed because of mild renal dysfunction and mild proteinuria. He had neither characteristic early symptoms nor a family history of Fabry disease. Histologic findings demonstrated diffuse global enlargement and foamy change of podocytes with markedly decreased number and enlargement of the glomeruli. Both his plasma and leukocyte α-galactosidase A (GLA) activities were markedly decreased, and the plasma globotriaosylsphingosine and urine globotriaosylceramide levels were increased. Gene analysis revealed a missense mutation, R112H, in the GLA gene, which had been reported in the later-onset phenotype of Fabry patients. He is now under treatment with enzyme replacement therapy and an angiotensin-converting enzyme inhibitor. CONCLUSION: This case indicated the possible co-occurrence of Fabry nephropathy and oligonephropathy. For early diagnosis and timely management, careful examinations for proteinuria and renal function, in addition to establishing an effective screening system for Fabry disease, will be necessary.

[Present situation and new challenges for medical treatment of Kawasaki disease].

To predict resistance to intravenous immunoglobulin (MIG) treatment in patients with severe Kawasaki disease (KD), Gunma, Kurume, and Osaka risk scores were established. Using these scores, prospective randomised trials were performed, and addition of predni- solone or intravenous methylprednisolone -pulse to the standard regimen of IVIG improves coronary artery outcomes in severe KD. Adding the evidences of new and existing therapies, such as infliximab, cyclosporin A, ulinastatin, and plasma exchange, the clinical guideline for medical treatment of the acute phase of KD was revised in 2012. Additional large cohort studies are needed to clarify the applicability of intensive initial treatment. Challenges for the future are: 1) clarification of etiology and establishment of specific therapy, 2) establishment of personalized therapy using genetic markers related to the severity of KD.

Efficacy of immunoglobulin plus prednisolone for prevention of coronary artery abnormalities in severe Kawasaki disease (RAISE study): a randomised, open-label, blinded-endpoints trial.

BACKGROUND: Evidence indicates that corticosteroid therapy might be beneficial for the primary treatment of severe Kawasaki disease. We assessed whether addition of prednisolone to intravenous immunoglobulin with aspirin would reduce the incidence of coronary artery abnormalities in patients with severe Kawasaki disease. METHODS: We did a multicentre, prospective, randomised, open-label, blinded-endpoints trial at 74 hospitals in Japan between Sept 29, 2008, and Dec 2, 2010. Patients with severe Kawasaki disease were randomly assigned by a minimisation method to receive either intravenous immunoglobulin (2 g/kg for 24 h and aspirin 30 mg/kg per day) or intravenous immunoglobulin plus prednisolone (the same intravenous immunoglobulin regimen as the intravenous immunoglobulin group plus prednisolone 2 mg/kg per day given over 15 days after concentrations of C-reactive protein normalised). Patients and treating physicians were unmasked to group allocation. The primary endpoint was incidence of coronary artery abnormalities during the study period. Analysis was by intention to treat. This trial is registered with the University Hospital Medical Information Network clinical trials registry, number UMIN000000940. FINDINGS: We randomly assigned 125 patients to the intravenous immunoglobulin plus prednisolone group and 123 to the intravenous immunoglobulin group. Incidence of coronary artery abnormalities was significantly lower in the intravenous immunoglobulin plus prednisolone group than in the intravenous immunoglobulin group during the study period (four patients [3%] vs 28 patients [23%]; risk difference 0·20, 95% CI 0·12-0·28, p<0·0001). Serious adverse events were similar between both groups: two patients had high total cholesterol and one neutropenia in the intravenous immunoglobulin plus prednisolone group, and one had high total cholesterol and another non-occlusive thrombus in the intravenous immunoglobulin group. INTERPRETATION: Addition of prednisolone to the standard regimen of intravenous immunoglobulin improves coronary artery outcomes in patients with severe Kawasaki disease in Japan. Further study of intensified primary treatment for this disease in a mixed ethnic population is warranted. FUNDING: Japanese Ministry of Health, Labour and Welfare.