Naoya Fujita

Age-Dependent Decrease in Serum Soluble Interferon-Gamma Receptor (sIFN-γR) in Healthy Japanese Individuals; Population Study of Serum sIFN-γR Level in Japanese

Abstract We planned to investigate the clinical significance of serum soluble interferon-gamma receptor (sIFN-γR) level in pediatric patients. The diagnostic application of the measurement of serum sIFN-γR level depends critically on the control value. However, there is no information of the control value of serum sIFN-γR for children. In the present study, we determined the serum sIFN-γR level of healthy Japanese children using an ELISA. The serum sIFN-γR level of children (0–14 years old) was significantly higher than that of adults (over 15 years old) (p < 0.01, n = 104). Thus, it is recommended that, when the serum sIFN-γR level of patients is evaluated, it should be compared against age-matched controls. We also preliminarily applied this assay as a diagnostic parameter for the patients with diarrhea positive (D +) hemolytic uremic syndrome (HUS).

Pediatric late-onset anaphylaxis caused by natto (fermented soybeans)

Natto is a traditional Japanese food made from soybeans fermented by Bacillus subtilis, which is known as natto-kin in Japan. Natto contains various enzymes, vitamins, amino acids, and other nutrients unique to this fermented product, which give it distinctive health and medical benefits. Recently, natto has been widely consumed in the West as a Japanese health food. In general, soybean allergens are inactivated by fermentation, and allergic reactions after the ingestion of fermented food products (such as shoyu, miso, and natto) are rare, even in patients with soybean allergy. Tsuji and colleagues reported that a major soybean allergen, Gly m Bd 30K was detected at high concentration in soybean seed, tofu, kori-dofu, and yuba, but was not detected in miso, shoyu, and natto. However, there have been several reports of natto-induced late-onset anaphylaxis, which is characterized by a reaction occurring several hours after ingestion, in patients without allergic reactions to other soybean or soybean-derived food products. All of the previously reported cases of natto-induced anaphylaxis have been in male adults and, to date, no pediatric cases have been reported. Here we report a pediatric case of late-onset anaphylaxis caused by natto.

Urinary Evaluation of the Balance Between the Soluble Interferon-Gamma Receptor (IFN-γR1) and the Interleukin-4 Receptor (IL-4Rα) in Children with Vesicoureteral Reflux

Abstract We planned to investigate the urinary soluble cytokine receptor profile in patients with vesico-ureteric reflux (VUR). The urine levels of soluble interferon-γ receptor R1 (sIFN-γR) and soluble interleukin-4 receptor α (sIL-4R) were measured using an ELISA technique. The urine levels of sIFN-γR in the patients with VUR were significantly higher than those in the healthy controls (p < 0.001). On the other hand, although the urine sIL-4R levels in the patients with VUR were also higher than those in the controls, there were no significant differences between them. The urinary soluble receptor levels did not correlate with the clinical severity of VUR. These results suggest that there may be an immunological basis to VUR complicatedly.

Age-dependent decreases in serum soluble interleukin-1 receptor type I (sIL-1RI) in healthy individuals: a population study of serum sIL-1RI levels in Japanese subjects.

The levels of several soluble cytokine receptors in body fluids of healthy individuals change with age. Clinical application of the measurement of the serum soluble interleukin‐1 receptor type I (sIL‐1RI) level depends critically on the samples used as the controls. At present, there is no information regarding the levels of serum sIL‐1RI in healthy subjects. The purpose of this study is to reveal the age‐related changes that occur in the serum sIL‐1RIlevels of healthy individuals. We determined the serum sIL‐1RI levels of healthy Japanese children using ELISA. The serum sIL‐1RI level of children (0–14 years) was significantly higher than that of adults (more than 15 years) (P=0.0138, n=90). Thus, it is recommended that when the serum sIL‐1RI level of patients is evaluated, it should be compared against age‐matched controls. J. Clin. Lab. Anal. 23:175–178, 2009.

Urinary evaluation of the balance between soluble interferon-gamma receptor (IFN-γR1) and interleukin-4 receptor (IL-4Rα)

To elucidate the usefulness of the simultaneous analysis of multiple kinds of soluble cytokine receptors in urine specimens, we determined the levels of both the soluble interferon-gamma receptor alpha chain (sIFN-gammaR1, Th1-type cytokine receptor) and the soluble interleukin 4-receptor alpha chain (sIL-4Ralpha, Th2-type cytokine receptor) in the urine of healthy subjects as reference values and preliminarily applied this method to evaluate patients with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as the diagnostic parameters. The urinary sIFN-gammaR levels of children were significantly lower than those of adults (p < 0.01, n = 107). On the other hand, there was no significant difference between the urine sIL-4R levels of adults and children. Statistical correlation between sIFN-gammaR and sIL-4R values was not observed (p = 0.705). On the day of onset of HUS, the urine sIFN-gammaR levels of the patients (n = 6) with HUS were higher than those of the healthy control group (n = 67) (p < 0.01); however, there was no significant difference in the sIL-4R levels between both groups. The urine evaluation of the balance between the soluble cytokine receptors might be informative for the immune states of HUS patients.

Solute Clearance and Fluid Removal: Large-Dose Cyclic Tidal Peritoneal Dialysis: Large-Dose Cyclic TPD

Large‐dose cyclic tidal peritoneal dialysis (TPD) is an original prescription of TPD involving frequent infusion and drainage of the dialysate to increase weekly urea clearance normalized to total body water (Kt/Vurea) and fluid removal. This study aimed to evaluate the efficiency of solute clearance and fluid removal achieved with large‐dose cyclic TPD compared to that achieved with nightly peritoneal dialysis (NPD). Seventeen patients with end‐stage renal disease, for whom maintenance PD was changed from NPD to large‐dose cyclic TPD, were enrolled. Their median age at administration of PD was 4.9 years. Kt/Vurea and fluid removal were compared between large‐dose cyclic TPD and NPD. The median peritoneal Kt/Vurea achieved with NPD and large‐dose cyclic TPD was 1.5 and 2.7, respectively. The median peritoneal Kt/Vurea per hour with large‐dose cyclic TPD was significantly higher than that with NPD (P = 0.0003). Among nine patients who used dialysates with the same glucose concentration for both NPD and large‐dose cyclic TPD, nightly fluid removal amount per hour with large‐dose cyclic TPD was significantly higher than that with NPD (P = 0.0039). Large‐dose cyclic TPD is a useful prescription of PD for increasing Kt/Vurea and fluid removal.

Congenital chloride diarrhea needs to be distinguished from Bartter and Gitelman syndrome

Pseudo-Bartter/Gitelman syndrome (p-BS/GS) encompasses a clinically heterogeneous group of inherited or acquired disorders similar to Bartter syndrome (BS) or Gitelman syndrome (GS), both renal salt-losing tubulopathies. Phenotypic overlap frequently occurs between p-BS/GS and BS/GS, which are difficult to diagnose based on their clinical presentation and require genetic tests for accurate diagnosis. In addition, p-BS/GS can occur as a result of other inherited diseases such as cystic fibrosis, autosomal dominant hypocalcemia, Dent disease, or congenital chloride diarrhea (CCD). However, the detection of the variants in genes other than known BS/GS-causing genes by conventional Sanger sequencing requires substantial time and resources. We studied 27 cases clinically diagnosed with BS/GS, but with negative genetic tests for known BS/GS genes. We conducted targeted sequencing for 22 genes including genes responsible for tubulopathies and other inherited diseases manifesting with p-BS/GS symptoms. We detected the SLC26A3 gene variants responsible for CCD in two patients. In Patient 1, we found the SLC26A3 compound heterozygous variants: c.354delC and c.1008insT. In Patient 2, we identified the compound heterozygous variants: c.877G > A, p.(Glu293Lys), and c.1008insT. Our results suggest that a comprehensive genetic screening system using targeted sequencing is useful for the diagnosis of patients with p-BS/GS with alternative genetic origins.

Survival of a very low‐birthweight infant with Potter sequence on long‐term hemodialysis

Recent advances in neonatal cardiorespiratory management and neonatal renal replacement therapy have led to occasional reports of favorable short‐term and long‐term outcomes for Potter sequence, once thought to be fatal. The present patient was a girl born at a gestational age of 34 weeks 4 days with a birthweight of 1398 g. She was diagnosed with Potter sequence complicated by pulmonary hypoplasia due to left renal agenesis and small right kidney. Hemodialysis was started because anuria persisted even after persistent pulmonary hypertension receded and cardiorespiratory status improved. Peritoneal dialysis during the clinical course failed to achieve stability because of pericatheter leakage and frequent obstruction of the peritoneal dialysis catheter; in the meantime, hemodialysis was also performed. Once bodyweight passed 3.5 kg, peritoneal dialysis became more feasible with stability; the patient was discharged at 9 months and at the time of writing was on peritoneal dialysis at home, and renal transplantation was planned.

Neonatal renal venous thrombosis followed by secondary pseudohypoaldosteronism

A male infant was diagnosed as having renal venous thrombosis (RVT) in association with bilateral flank masses, macroscopic hematuria, and thrombocytopenia. In the course of supportive treatment, hyponatremia, hyperkalemia, and metabolic acidosis became prominent. Plasma renin activity (PRA) and aldosterone increased markedly. Treatment with sufficient sodium chloride and sodium bicarbonate intake was effective. It is important to note that tubular damage by RVT causes secondary pseudohypoaldosteronism.

DETERMINATION OF SOLUBLE TUMOR NECROSIS FACTOR-α RECEPTOR TYPE I (TNFRI) AND II (TNFRII) IN THE URINE OF HEALTHY JAPANESE SUBJECTS

We determined the urinary soluble tumor necrosis factor-α receptor type I (sTNFRI) and type II (sTNFRII) levels in healthy Japanese individuals to establish a reference value by means of specific ELISA. It was found that there were no significant differences between the urine sTNFRI and sTNFRII levels of children and adults. To demonstrate the usefulness of the reference value for children, we measured the urine sTNFRI and sTNFRII levels of children with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as a preliminary study. The urine sTNFRI and sTNFRII levels of the patients with HUS were markedly higher than those of healthy children from the onset of D + HUS. Our reliable reference value for healthy children will allow us to discriminate between normal and pathological conditions in future studies.