Kenichi Satomura

Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Ōsaka, Japan

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Publications (21)63.28 Total impact

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    ABSTRACT: Background: The present study aimed to obtain information enabling optimisation of the clinical effect of mizoribine (MZR) in pediatric patients with kidney disease. Methods: A total of 105 pediatric patients with kidney disease treated at our institutions were enrolled. Kidney transplant patients were excluded. Population pharmacokinetic analysis of MZR was performed based on serum concentration data. Area under the curve from time zero to infinity (AUC∞) and maximal concentration (C max) were calculated by Bayesian analysis. Results: In children, the appearance of MZR in the blood tended to be slower and the subsequent rise in blood concentration tended to be more sluggish, compared to healthy adults. Apparent volume of distribution and oral clearance were also higher in children compared to adults. A significant positive correlation was observed between patient age and AUC∞. There were significant differences of AUC∞ and C max by age group. No relationship was observed between the administration method of MZR and serum concentration. Conclusion: The pharmacokinetics of MZR was different in children compared to adults. To obtain the expected clinical efficacy, the regular MZR dosage schedule (2-3 mg/kg/day) might be insufficient for pediatric patients. In particular, younger patients might require a higher dosage of MZR per unit body weight.
    No preview · Article · Dec 2015 · Clinical and Experimental Nephrology
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    ABSTRACT: End-stage renal disease (ESRD) in children is considered a rare, but serious condition. Epidemiological and demographic information on pediatric ESRD patients around the world is important to better understand this disease and to improve patient care. The Japanese Society for Pediatric Nephrology (JSPN) reported epidemiological and demographic data in 1998. Since then, however, there has been no nationwide survey on Japanese children with ESRD. The JSPN conducted a cross-sectional nationwide survey in 2012 to update information on the incidence, primary renal disease, initial treatment modalities, and survival in pediatric Japanese patients with ESRD aged less than 20 years during the period 2006-2011. The average incidence of ESRD was 4.0 per million age-related population. Congenital anomalies of the kidney and urinary tract were the most common cause of ESRD, present in 39.8 % of these patients. In addition, 12.2 % had focal segmental glomerulosclerosis and 5.9 % had glomerulonephritis. Initial treatment modalities in patients who commenced renal replacement therapy (RRT) consisted of peritoneal dialysis, hemodialysis, and pre-emptive transplantation (Tx) in 61.7, 16.0, and 22.3 %, respectively. The Japanese RRT mortality rate was 18.2 deaths per 1000 person-years of observation. The incidence of ESRD is lower in Japanese children than in children of other high-income countries. Since 1998, notably, there has been a marked increase in pre-emptive Tx as an initial treatment modality for Japanese children with ESRD.
    No preview · Article · Jan 2015 · Clinical and Experimental Nephrology
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    ABSTRACT: Our understanding of inherited salt-losing tubulopathies has improved with recent advances in molecular genetics. However, the terminology of Bartter syndrome and Gitelman syndrome does not always accurately reflect their pathophysiological basis or clinical presentation, and some patients are difficult to diagnose from their clinical presentations. In the present study, we conducted molecular analysis and diuretic tests for patients with inherited salt-losing tubulopathies to clarify the pharmacological characteristics of these disorders. We detected mutations and subsequently conducted diuretic tests using furosemide and thiazide for 16 patients with salt-losing tubulopathies (two with SLC12A1; two with KCNJ1; nine with CLCNKB; and three with SLC12A3). Patients with SLC12A1 mutations showed no response to furosemide, whereas those with SLC12A3 mutations showed no response to thiazide. However, patients with CLCNKB mutations showed no response to thiazide and a normal response to furosemide, and those with KCNJ1 mutations showed a good response to both diuretics. This study revealed the following characteristics of these disorders: 1) subjects with CLCNKB mutations showed one or more biochemical features of Gitelman syndrome (including hypomagnesemia, hypocalciuria, and fractional chloride excretion insensitivity to thiazide administration); and 2) subjects with KCNJ1 mutations appeared to show normal fractional chloride excretion sensitivity to furosemide and thiazide administration. These results indicate that these disorders are difficult to distinguish in some patients, even when using diuretic challenge. This clinical report provides important findings that can improve our understanding of inherited salt-losing tubulopathies and renal tubular physiology.
    No preview · Article · Dec 2010 · The Journal of Clinical Endocrinology and Metabolism
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    ABSTRACT: The aim of this study was to evaluate limited sampling designs to estimate the maximal concentration (C(max)) and area under the curve (AUC) of mizoribine in pediatric patients with renal disease. We utilized 48 serum mizoribine concentration profiles obtained from the full (6-point) sampling pharmacokinetic test, and estimated 48 individual C(max) and AUC values accurately with Bayesian analysis using the full sampling data. We then developed limited sampling models (LSM) for C(max) and AUC using 1-4 serum mizoribine concentration data points. The C(max) and AUC estimation performance of the Bayesian and LSM analysis was fairly good in the 3-point (2, 3, and 6 hr after the dose) sampling design. In addition, the C(max) estimation performance of the Bayesian and LSM analysis deteriorated only marginally even in the 1-point (3 hr) sampling design. On the other hand, the AUC estimation performance seemed to be inadequate in the 1-point (3 hr) sampling design; however, it improved markedly in the 2-point (3 and 6 hr) sampling design. These findings suggested that the 1-point (3 hr) sampling design is promising for approximate C(max) estimation, but that the 2-point (3 and 6 hr) sampling design is preferable to estimate the AUC of mizoribine.
    No preview · Article · Oct 2010 · Drug Metabolism and Pharmacokinetics
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    ABSTRACT: Background and Methods. The NPHS1gene was analysed in different five Japanese patients with congenital nephrotic syndrome (CNS) from the patients in a previous report (Sako M, Nakanishi K, Obana M et al. Analysis of NPHS1, NPHS2, ACTN4, and WT1 in Japanese patients with congenital nephrotic syndrome. Kidney Int 2005; 67: 1248–1255) that suggested that the mutation of NPHS1 was not a major cause of CNS in Japanese patients. Genomic DNA was extracted from leukocytes, and all exons and exon–intron boundaries were analysed for NPHS1 using polymerase chain reaction and direct sequencing. Results and Conclusions. Compound heterozygous mutations of NPHS1 were found in four patients and homozygous mutations in one patient. Interestingly, three patients out of five had the same mutation in NPHS1: nt2515(delC). Parents who had this mutation heterozygously were from neighbouring prefectures. Two among five patients in this research and one in the previous report (Kidney Int 2005; 67:1248–1255) had the same mutation: 736G > T in exon 7. All mutations including these two mutations except for one have never been reported outside of Japan yet.
    Preview · Article · Apr 2009 · Nephrology Dialysis Transplantation
  • Takehisa Yamamoto · Kenichi Satomura · Shintaro Okada · Keiichi Ozono
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    ABSTRACT: The aim of the present study was to investigate the predictive parameters for encephalopathy in complete hemolytic uremic syndrome (HUS) in a large outbreak of O157: H7 infection in 1996. A total of 182 inpatients, 71 of whom had complete HUS, including 12 patients with neurological complications, and 46 colitis patients were studied. Presenting signs and symptoms (n = 115) and laboratory data (n = 69) were analyzed using monovariate and multivariate analysis. After adjusting for age and gender, logistic regression showed that presenting symptoms such as bloody diarrhea (odds ratio [OR] = 7.39), proteinuria (OR = 6.16), hematuria (OR = 8.31), oliguria (OR = 17.4) and a pale face (OR = 10.7) were useful for predicting complete HUS. Also, increased white blood cell counts >12,000 microL/mL (OR = 10.0) and C-reactive protein >1.5 mg/dL (OR = 7.39) at the onset of infection, were useful as predictive laboratory parameters. To predict neurological complications in complete HUS patients, the average daily increase of lactate dehydrase >1200 IU/L per day (OR = 26.3) and creatinine >0.5 mg/dL per day (OR = 12) were found to be useful on multivariate logistic regression. There are useful predictive clinical factors for neurological complications in complete HUS.
    No preview · Article · Apr 2009 · Pediatrics International
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    ABSTRACT: McCune-Albright syndrome is characterized by café-au-lait spot, multiple endocrine hyperfunction, and polyostotic fibrous dysplasia. A somatic point mutation of Gsalpha protein leads to an increase in the Gsalpha-associated hormone activity in McCune-Albright syndrome. Because cyclic adenosine 3',5'-monophosphate stimulates the dopamine beta hydroxylase gene, an activating mutation of the Gsalpha protein may cause the hyperproduction of norepinephrine via dopamine. We report on a 9-year-old girl with McCune-Albright syndrome complicated by severe arterial hypertension. The urinary excretion of norepinephrine was 5- to 10-fold higher than in age-matched controls. Meta-iodobenzylguanidine scintigraphy and positron emission tomography/computed tomography (PET/CT) revealed no hot spots. These findings suggest that severe hypertension might be due to an activating mutation of Gsalpha protein in sympathetic ganglia. Because of the reported association of GNAS1 gene polymorphism with hypertension, our patient provides further evidence for a role of Gsalpha protein in hypertension.
    No preview · Article · Nov 2008 · European Journal of Pediatrics
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    ABSTRACT: Hemolytic uremic syndrome (HUS) is characterized by acute renal failure, thrombocytopenia and hemolytic anemia. Cases accompanied by prodromal gastrointestinal tract symptoms are referred to as typical HUS. Some severe HUS patients require dialysis or develop central nervous system (CNS) disorders after the onset of HUS. Patients who developed typical HUS in 2001 and 2002 in Japan, 127 in all, were the study subjects. To identify the risk factors for the development of a severe clinical course, clinical and laboratory data were analyzed on logistic regression. Two of the 127 patients died (1.6%): one from acute cardiac failure and the other from a CNS disorder. Thirty-five patients required dialysis (28%) and 30 had CNS symptoms (24%). Multivariate analysis indicated that the risk factors for need for dialysis were serum sodium and alanine aminotransferase (ALT) levels of </=130 mEq/L and >/=70 IU/L, respectively, at the onset of HUS and those for developing CNS disorders were dialysis and C-reactive protein (CRP) >/=5.0 mg/dL at the onset of HUS. Because patients with these risk factors, such as low serum sodium, high ALT or high CRP levels, may require dialysis or develop CNS disorders, they should be treated carefully in the early stage of HUS.
    No preview · Article · Aug 2008 · Pediatrics International
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    ABSTRACT: Renal tubular dysgenesis is a critical disorder characterized by the Potter phenotype and severe hypotension in the early neonatal period. We herein report a 3-year-old female with renal tubular dysgenesis. Endocrinological studies showed a high plasma renin activity (over 49.2 ng/ml/h; normal range 2.0-15.2), high active renin concentration (1,823.5 pg/ml; normal range 2.4-21.9), and low angiotensin-converting enzyme (ACE) concentration (1.7 U/l; normal range 8.3-21.4). Taken together, these findings suggested an abnormality of the ACE gene, ACE. Direct sequencing analysis revealed two novel deletions in the coding region of ACE. We conclude that hormonal analysis of the renin-angiotensin system can aid in identifying the responsible genes and help with efficient gene analysis and pathophysiological considerations.
    No preview · Article · Jun 2008 · European Journal of Pediatrics
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    ABSTRACT: Type III Bartter syndrome (BS) (OMIM607364) is caused by mutations in the basolateral chloride channel CIC-Kb gene (CLCNKB). The CLCNKB gene is sometimes reported as having a large deletion mutation, but all cases reported previously were large homozygous deletions and a large heterozygous deletion is impossible to detect by direct sequencing. This report concerns a genetic analysis of five Japanese patients with type III BS. To identify the mutations, we used polymerase chain reaction (PCR) and direct sequencing. To detect large heterozygous deletion mutations of the CLCNKB gene, we conducted semiquantitative PCR amplification using capillary electrophoresis. The result was that four mutations were identified, comprising one novel 2-bp deletion mutation, an entire heterozygous deletion, and a heterozygous deletion mutation of exons 1 and 2. The nonsense mutation W610X was detected in all patients, and this mutation is likely to constitute a founder effect in Japan. Capillary electrophoresis is a new method and extremely useful for detecting large heterozygous deletions, and should be used to examine type III BS cases in whom only a heterozygous mutation has been detected by direct sequencing. This is the first report to identify large heterozygous deletion mutations in the CLCNKB gene in patients with type III BS.
    Full-text · Article · Oct 2007 · Pediatric Research
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    ABSTRACT: We isolated genomic DNA from 15 patients with branchio-oto-renal (BOR) syndrome or BOR-related conditions. Seven patients had BOR syndrome (two familial and five sporadic), and eight had deafness and renal malformations without branchial fistula (BOR-related conditions). We analyzed all exons and exon-intron boundaries of EYA1 and SIX1 using the polymerase chain reaction (PCR) direct sequencing, and characterized their mutations. In some patients, analysis of mRNA by reverse transcription (RT)-PCR was performed to examine whether the mutation affects the mRNA splicing. We identified five novel disease-causing heterozygous EYA1 mutations in five patients with BOR syndrome (two familial and three sporadic, 5/7=71%), but EYA1 and SIX1 mutations were not detected in the other two patients with BOR syndrome or any of the patients with BOR-related conditions. The detected EYA1 mutations were two nonsense mutations, two splicing acceptor-site mutations, and a point mutation (G>T) of the first base of exon 10. Analysis of mRNA by RT-PCR direct sequencing revealed that the latter point mutation led to the skipping of exon 10. In conclusion, (1) EYA1 mutations are a major cause of BOR syndrome in Japanese, (2) EYA1 and SIX1 mutations were not a major cause of BOR-related conditions, (3) we demonstrated for the first time that the point mutation (G>T) of the first base of the exon in EYA1 gene induced exon skipping.
    No preview · Article · Apr 2006 · Pediatric Nephrology
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    ABSTRACT: Congenital nephrotic syndrome (CNS) causes significant renal failure, and is classified into two types: (1) Finnish type; and (2) other, including diffuse mesangial sclerosis. Mutations of NPHS1 and NPHS2, which encode the slit diaphragm components nephrin and podocin, cause CNS and autosomal-recessive familial steroid-resistant nephrotic syndrome, respectively. Most patients with Finnish-type CNS in Europe and the United States have NPHS1 mutations. However, NPHS2 mutations have been detected in some cases. Mutations in ACTN4, encoding alpha-actinin-4, cause an autosomal-dominant focal segmental glomerulosclerosis. alpha-actinin-4 stabilizes the podocyte cytoskeleton structure, connecting with actin filaments. WT1 mutations, causing Wilm's tumor, have been demonstrated in some CNS patients with diffuse mesangial sclerosis. Systematic investigation of genes for CNS in Japan has never been performed. To clarify the role of mutations in these four genes, we used polymerase chain reaction (PCR) and direct sequencing to investigate all exons and exon-intron boundaries for these genes in 13 unrelated CNS patients from regional pediatric kidney disease centers in Japan. A novel homozygous nonsense mutation of NPHS1, E246X in exon 7, and a novel homozygous deletion mutation of NPHS1, 2156_2163del in exon 16 were detected in one patient each. A novel homozygous nonsense mutation of NPHS2, R196X in exon 5, was found in one patient, and the same heterozygous nonsense mutation was detected in another. No ACTN4 or WT1 mutations were detected. These studies demonstrate that mutation of NPHS1 is not a major cause of CNS in Japanese patients, and that mutation of NPHS2 can be responsible for CNS in this population.
    Full-text · Article · May 2005 · Kidney International
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    ABSTRACT: McCune-Albright syndrome (MAS) is sometimes complicated by hypophosphatemia and abnormally low levels of 1,25(OH)(2)D in the presence of hypophosphatemia. Recently, fibroblast growth factor 23 (FGF-23) was reported as a phosphaturic and a causal factor of abnormal vitamin D metabolism. This abnormal phosphate and vitamin D metabolism is well known to be found in oncogenic and X-linked hypophosphatemia. We furthermore reported increased circulating plasma FGF-23 levels in patients with oncogenic and X-linked hypophosphatemia. To determine whether FGF-23 may be involved in the pathogenesis of MAS, we measured plasma FGF-23 levels in six MAS patients. As a control for hypophosphatemia, we also investigated the plasma FGF-23 levels in two patients with hereditary hypophosphatemic rickets with hypercalciuria (HHRH). We also investigated the correlation of plasma FGF-23 levels with serum phosphate and 1,25(OH)(2)D levels after short-term pamidronate therapy in three MAS patients. Plasma FGF-23 levels were significantly increased in patients with MAS compared to normal controls, whereas they were not increased in HHRH patients. Serum phosphate levels of the MAS patients were significantly lower than those observed in normal controls. Plasma FGF-23 levels showed significant negative correlation with serum phosphate concentrations. In three MAS patients, pamidronate therapy decreased plasma FGF-23 levels, which showed significant negative correlation with serum 1,25(OH)(2)D concentrations. These data suggested that FGF-23 is a possible causal factor for hypophosphatemia and abnormal vitamin D metabolism in MAS.
    No preview · Article · Feb 2005 · Journal of Bone and Mineral Metabolism
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    ABSTRACT: Podocin is an integral membrane protein encoded by NPHS2, which is mapped to 1q25-31 and is exclusively expressed in glomerular podocytes. NPHS2 mutations are responsible for autosomal recessive familial steroid-resistant nephrotic syndrome (SRNS) with minor glomerular abnormalities or focal segmental glomerulosclerosis (FSGS), which is characterized by early childhood onset (age less than 6 years) and rapid progression to chronic renal insufficiency. This gene mutation is also responsible for an adolescent/adult onset form of autosomal recessive familial FSGS with heavy proteinuria. It has been demonstrated that sporadic SRNS and heavy proteinuria are also due to NPHS2 gene mutations. We isolated genomic DNA from 36 Japanese children with chronic renal insufficiency caused by SRNS or heavy proteinuria, and analyzed all eight exons and exon-intron boundaries of NPHS2 using the polymerase chain reaction and direct sequencing. The age at onset of disease was 3.9+/-0.5 years. There were 29 patients with SRNS and 7 with heavy proteinuria without nephrotic syndrome at the onset, but all patients developed chronic renal insufficiency 4.6+/-0.8 years after the onset. A new homozygous missense variant of NPHS2, G34E (G101A) in exon 1, was detected in 1 of 36 patients. However, this homozygous variant was also found in 1 of 44 normal controls, suggesting that the mutation is a polymorphism. Two silent variants (T954C and A1038G) in exon 8 of this gene were also identified in some of the patients and normal controls, indicating that the silent variants are also polymorphisms. There was no significant difference in the genotypic and allelic frequencies of T954C and A1038G polymorphisms between the patients and normal controls. In conclusion, NPHS2 gene mutations are not a major cause of chronic renal insufficiency caused by sporadic SRNS or heavy proteinuria in Japanese children.
    No preview · Article · Jun 2003 · Pediatric Nephrology
  • Katsusuke Yamamoto · Yoko Santo · Kenichi Satomura
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    ABSTRACT: Denys-Drash syndrome is a rare disorder consisting of pseudohermaphrodism, Wilms' tumor and nephropathy. We describe here a boy with severe hypospadias and undescended testes, who presented with end-stage renal failure at the age of 1 year and 8 months when he was referred to our hospital. Emergency hemodialysis was performed because of oliguria, edema and severe hypertension, and then peritoneal dialysis was started. The findings of the renal biopsy showed diffuse mesangial sclerosis, consistent with the characteristic change in Denys-Drash syndrome. The analysis of WT1 gene revealed a G-to-A point mutation at 1,186 resulting in a change from Asp to Asn at 396 in exon 9. Since he had no urine output and his kidneys were not functional and in addition, patients with this mutation have been reported to have a high risk of Wilms' tumor, bilateral nephrectomy was performed. The removed kidneys showed no malignancies. Since Denys-Drash syndrome is frequently associated with Wilms' tumor, renal biopsy and gene analysis should be performed on male patients with gonadal anomaly, such as hypospadias and/or undescended testes, and proteinuria.
    No preview · Article · Feb 2003 · Nippon Jinzo Gakkai shi
  • T Michigami · T Kageyama · K Satomura · M Shima · K Yamaoka · M Nakayama · K Ozono
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    ABSTRACT: A case of infantile malignant osteopetrosis is described. The patient died from respiratory hemorrhage at 7 months of age despite treatment that included high doses of active vitamin D and administration of interferon-gamma. A postmortem examination revealed the presence of many osteoclasts in the bone, which lacked ruffled borders. This observation was consistent with the histology of bone reported in Atp6i-knockout mice, which lack the gene encoding the a3 subunit of vacuolar-type H(+)-adenosine triphosphatase (ATPase). Sequence analysis of the TCIRG1 gene encoding the a3 subunit revealed two novel mutations: a deletion/insertion mutation in exon 9 and a T-to-C transition at the splice donor site of intron 19. The former mutation caused a frame shift and premature stop codon. The latter was associated with abnormal splicing, which was confirmed by sequencing the products amplified by reverse transcription-polymerase chain reaction (RT-PCR), using total RNA from the liver specimen as template. Although several mutations in the TCIRG1 gene in infantile malignant osteopetrosis have been reported in other populations, this is the first case of a Japanese patient with a mutation identified in this gene. These results support the important role of the subunit in the function of the proton pump.
    No preview · Article · Mar 2002 · Bone
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    ABSTRACT: Hypophosphatasia is associated with a defect of the tissue-nonspecific alkaline phosphatase (TNSALP) gene. The onset and clinical severity are usually correlated in hypophosphatasia; patients with perinatal hypophosphatasia die approximately at the time of birth. In contrast, we describe a male neonatal patient with hypophosphatasia who had no respiratory problems and survived. He was compound heterozygous for the conversion of Phe to Leu at codon 310 (F310L) and the deletion of a nucleotide T at 1735 (delT1735), causing the frame shift with the result of the addition of 80 amino acids at the C-terminal of the protein. Because the C-terminal portion of TNSALP is known to be important for TNSALP to bind to the plasma membrane, the localization of wild-type and mutated TNSALP proteins was analyzed using green fluorescent protein chimeras. The expression vectors containing the complementary DNA of fusion proteins consisting of signal peptide, green fluorescent protein, and wild-type or mutated TNSALP, caused by delT1735 or F310L mutation, were introduced transiently or stably in Saos-2 cells. The delT1735 mutant failed to localize at the cell surface membrane, whereas the wild-type and the F310L mutants were located in the plasma membrane and cytoplasm. The assay for enzymatic activity of TNSALP revealed that the delT1735 mutant lost the activity and that the F310L mutant exhibited an enzymatic activity level that was 72% of the normal level. The F310L mutation was also detected in another neonatal patient with relatively mild (nonlethal) hypophosphatasia (reported in J Clin Endocrinol Metab, 81:4458-4461, 1996), suggesting that residual ALP activity of the F310L mutant contributes to the less severe phenotype. The patient is unique, with respect to a discrepancy between onset and clinical severity in hypophosphatasia.
    No preview · Article · Dec 1998 · Journal of Clinical Endocrinology & Metabolism
  • K Satomura · T Michigami · K Yamamoto · S Hosokawa
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    ABSTRACT: We report a rare case of glomerulocystic kidney disease (GCKD) with congenital hypothyroidism. A gigantic abdominal mass was noted at birth. There was no family history of renal cystic disease. Ultrasonography revealed diffuse granular cysts in the markedly enlarged kidneys. Blood examination showed moderate renal failure and hypothyroidism. Bilateral nephrectomy was conducted at 47 days of age to relieve respiratory failure and severe abdominal distention caused by the growing cystic kidneys. Histological findings of the kidney showed numerous glomerular cysts without renal dysplasia. There were no other malformations. These findings were compatible with GCKD.
    No preview · Article · Dec 1998 · Nippon Jinzo Gakkai shi
  • Katsusuke Yamamoto · Kenichi Satomura

    No preview · Article · Jan 1998 · Nihon Shoni Jinzobyo Gakkai Zasshi
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    ABSTRACT: Hypophosphatasia is associated with a defect of the tissue-non-specific alkaline phosphatase gene. We performed a mutational analysis in a surviving patient diagnosed at birth as having hypophosphatasia, on the basis of a low level of serum alkaline phosphatase (ALP) activity and characteristic radiographical findings. She had two sisters, one of whom died of respiratory failure complicated by perinatal hypophosphatasia; the other seemed healthy, with a relatively low activity level of ALP. The patient's parents also had low ALP activity. Sequence analysis of the tissue-nonspecific alkaline phosphatase gene was performed, using genomic DNA and total RNA from the skin fibroblasts of the patient and the peripheral mononuclear cells of her parents. The conversion of Phe to Leu at codon 310 (F310L) and Gly to Arg at 439 (G439R) were identified in the patient. Interestingly, the reconstructive experiments demonstrated that the F310L mutant exhibited an ALP activity level 65% of the normal level, whereas the mutant G439R had no activity. Moreover, the digestion by StuI, after a PCR using complementary DNA extracted from fibroblasts of the patient and lymphocytes of her father, revealed a relatively low messenger RNA level of F310L. These findings suggest that the neonatal case of hypophosphatasia was associated with compound mutations, one of which caused the loss of ALP activity and the other of which caused a slight reduction of the ALP activity, with a relatively low level of messenger RNA.
    No preview · Article · Jan 1997 · Journal of Clinical Endocrinology & Metabolism

Publication Stats

379 Citations
63.28 Total Impact Points


  • 2002-2015
    • Osaka Medical Center and Research Institute for Maternal and Child Health
      Izumi, Ōsaka, Japan
  • 1998-2010
    • Osaka Minami Medical Center
      Ōsaka, Ōsaka, Japan
  • 2005
    • Wakayama Medical University
      • Department of Pediatrics
      Wakayama, Wakayama, Japan