Chronological changes of serum exosome in preterm infants: A prospective study.

BACKGROUND: Exosomes, which are observed in all human fluid, including serum, are nanosized extracellular vesicles with a mechanism of intercellular communication. Potential clinical applications of exosomes in neonatal diseases have recently been discussed. However, the characteristics of exosomes in serum during early infancy is unclear. METHODS: In this prospective study, we evaluated the chronological changes in the concentration of serum-derived exosomes of 20 infants for 12 months after birth. RESULTS: The average concentration of serum-derived exosomes was 4.6 × 1010 particles/mL at birth and increased significantly until the age of 48 weeks. There was a moderate correlation between the gestational age and the concentration of serum-derived exosomes both at birth (r = 0.54, P = 0.01) and during the 8 weeks after birth (r = 0.48, P < 0.001). A multivariable analysis showed that gestational age at birth was associated with the concentration of serum-derived exosomes at birth (partial regression coefficient, 0.86; 95% confidence interval, 0.37-1.37; P = 0.002). CONCLUSIONS: The concentration of serum-derived exosomes in preterm infants increased both chronologically and by gestational age after birth. These basic data may help to further understand physiology of exosomes in preterm infants.

Poor Bifidobacterial Colonization Is Associated with Late Provision of Colostrum and Improved with Probiotic Supplementation in Low Birth Weight Infants.

This study aimed to evaluate the association between bifidobacterial colonization in low birth weight infants and perinatal factors, including the timing of initial colostrum and the effect of probiotics on this colonization. In this non-randomized controlled trial, we enrolled 98 low-birth-weight infants from a neonatal intensive care unit (NICU) in Japan. Infants were divided into three groups: group N (no intervention), group H (received non-live bifidobacteria), and group L (received live bifidobacteria). The number of bifidobacteria in the infants' stools at 1 month of age was measured using real-time polymerase chain reaction (PCR). We divided infants into "rich bifidobacteria" (≥104.8 cells/g feces) and "poor bifidobacteria" (<104.8 cells/g feces) subgroups. The ratio of "rich bifidobacteria" infants was 20/31, 34/36, and 30/30 in groups N, H, and L, respectively. In group N, the "rich bifidobacteria" group received first colostrum significantly earlier than the "poor bifidobacteria" group (1 day vs. 4 days, P < 0.05). Compared with the N group, both groups H and L had a significantly high proportion of "rich bifidobacteria" infants (P < 0.05). Bifidobacterial colonization was poor in premature infants at 1 month compared with term infants, and the level of colonization was associated with the timing of initial provision of colostrum. Providing probiotics to premature infants can improve bifidobacterial colonization.

Bilirubin Uridine Diphosphate-glucuronosyltransferase Polymorphism as a Risk Factor for Prolonged Hyperbilirubinemia in Japanese Preterm Infants.

OBJECTIVE: To determine whether a variant of the bilirubin uridine diphosphate-glucuronosyltransferase gene (UGT1A1*6) is a risk factor for prolonged hyperbilirubinemia in preterm infants. STUDY DESIGN: UGT1A1 genotypes in 46 Japanese preterm infants (<37 weeks of gestation) were compared with UGT1A1 genotypes in 38 control infants, using polymerase chain reaction-direct sequencing. Prolonged unconjugated hyperbilirubinemia was defined as serum total bilirubin concentration of >150 µmol/L (8.77 mg/dL) beyond 14 days of life. RESULTS: In the case group, 41 of 46 infants (89.1%) had a polymorphic variant, c.211G>A, p.G71R (UGT1A1*6). In the control group, 7 of 38 (18.4%) had UGT1A1*6. The allele frequency of UGT1A1*6 was 0.641 in the prolonged hyperbilirubinemia group, which was significantly higher than in the control group (0.092; P < .001). In total, 39 of 46 infants in the case group were breast fed, and only 10 infants in the control group were breast fed. CONCLUSIONS: These data suggest that UGT1A1*6 is a risk factor for prolonged unconjugated hyperbilirubinemia in preterm infants in Japan. Given the different rate of breast feeding in this study, additional data are necessary for drawing a definitive conclusion.

Bifidobacterium bifidum OLB6378 Simultaneously Enhances Systemic and Mucosal Humoral Immunity in Low Birth Weight Infants: A Non-Randomized Study.

Probiotic supplementation has been part of the discussion on methods to enhance humoral immunity. Administration of Bifidobacterium bifidum OLB6378 (OLB6378) reduced the incidence of late-onset sepsis in infants. In this non-randomized study, we aimed to determine the effect of administration of live OLB6378 on infants' humoral immunity. Secondly, we tried to elucidate whether similar effects would be observed with administration of non-live OLB6378. Low birth weight (LBW) infants weighing 1500-2500 g were divided into three groups: Group N (no intervention), Group L (administered live OLB6378 concentrate), and Group H (administered non-live OLB6378 concentrate). The interventions were started within 48 h after birth and continued until six months of age. Serum immunoglobulin G (IgG) levels (IgG at one month/IgG at birth) were significantly higher in Group L than in Group N (p < 0.01). Group H exhibited significantly higher serum IgG levels (p < 0.01) at one month of age and significantly higher intestinal secretory immunoglobulin A (SIgA) levels (p < 0.05) at one and two months of age than Group N. No difference was observed in the mortality or morbidity between groups. Thus, OLB6378 administration in LBW infants enhanced humoral immunity, and non-live OLB6378, which is more useful as a food ingredient, showed a more marked effect than the viable bacteria.

Gilbert Syndrome with Concomitant Hereditary Spherocytosis Presenting with Moderate Unconjugated Hyperbilirubinemia.

We experienced a case of a 19-year-old man with Gilbert syndrome with concomitant hereditary spherocytosis. The patient presented with moderate unconjugated hyperbilirubinemia, and inherited etiology was strongly suspected. The diagnosis of Gilbert syndrome was confirmed by the genetic analysis of the UGT1A1 gene, demonstrating UGT1A1*28 and compound heterozygote UGT1A1*6. In addition, since the laboratory findings and imaging studies revealed lysemia as well as gallstone and splenomegaly, a diagnosis of hereditary spherocytosis was made as a comorbidity. Both Gilbert syndrome and hereditary spherocytosis are hereditary diseases with a high frequency, and the hyperbilirubinemia may be exacerbated when these two diseases are concomitant.

Genotype of UGT1A1 and phenotype correlation between Crigler-Najjar syndrome type II and Gilbert syndrome.

BACKGROUND AND AIMS: Hereditary unconjugated hyperbilirubinemias, Crigler-Najjar syndrome type I, Crigler-Najjar syndrome type II (CN-2), and Gilbert syndrome (GS) all result from mutations of the bilirubin uridine 5'-diphosphate (UDP)-glucuronosyltransferase gene (UGT1A1). Often, to distinguish between CN-2 and GS is difficult because the borderline of the two syndromes is unclear. We analyzed the genotypes and phenotypes of 163 Japanese patients with CN-2 or GS. METHODS: Japanese patients (99 males and 64 females) with unconjugated hyperbilirubinemia were analyzed. Their serum bilirubin concentrations varied from 1.2 to 22.2 mg/dL (20 to 379 µM). Genetic analysis of UGT1A1 was performed by PCR-amplified direct sequencing. Association between serum bilirubin concentrations and genotypes group (typical CN-2, intermediate group, and typical GS) was studied. RESULTS: Most patients had biallelic mutations of UGT1A1. Moreover, many of them (78.5%) had multiple mutations. The mutation in typical CN-2 was a homozygous double missense mutation of p.[G71R:Y486D]. In typical GS group, four prevalent genotypes were detected: homozygous UGT1A1*28, UGT1A1*6/UGT1A1*28, and homozygous UGT1A1*6, and UGT1A1*27/UGT1A1*28. In the intermediate group, three genotypes, p.[G71R:Y486D]/UGT1A1*7, p.[G71R:Y486D]/UGT1A1*6, and homozygous UGT1A1*7, were detected. Serum bilirubin concentrations of typical CN-2, intermediate group, and typical GS are respectively 12.9 ± 5.1, 5.2 ± 2.2, and 2.8 ± 1.1 mg/dL. Serum bilirubin concentration among the three groups is statistically different (P < 0.0001). CONCLUSIONS: The serum bilirubin concentration varied continuously from GS to CN-2 depending on genotypes. Because of the combination of the mutations and polymorphisms, many patients showed intermediate serum bilirubin concentration between two syndromes. Clinically, it is difficult to distinguish clearly between the two syndromes.

Two Different UGT1A1 Mutations causing Crigler-Najjar Syndrome types I and II in an Iranian Family.

BACKGROUND: Crigler-Najjar syndrome type I (CN-1) and type II (CN-2) are rare hereditary unconjugated hyperbilirubinemia disorders. However, there have been no reports regarding the co-existence of CN-1 and CN-2 in one family. We experienced a case of an Iranian family that included members with either CN-1 or CN-2. Genetic analysis revealed a mutation in the bilirubin UDP-glucuronosyltransferase (UGT1A1) gene that resulted in residual enzymatic activity. CASE REPORT: The female proband developed severe hyperbilirubinemia [total serum bilirubin concentration (TB) = 34.8 mg/dL] with bilirubin encephalopathy (kernicterus) and died after liver transplantation. Her family history included a cousin with kernicterus (TB = 30.0 mg/dL) diagnosed as CN-1. Her great grandfather (TB unknown) and uncle (TB = 23.0 mg/dL) developed jaundice, but without any treatment, they remained healthy as CN-2. RESULTS: The affected cousin was homozygous for a novel frameshift mutation (c.381insGG, p.C127WfsX23). The affected uncle was compound heterozygous for p.C127WfsX23 and p.V225G linked with A(TA)7TAA. p.V225G-UGT1A1 reduced glucuronidation activity to 60% of wild-type. Thus, linkage of A(TA)7TAA and p.V225G might reduce UGT1A1 activity to 18%-36 % of the wild-type. CONCLUSION: Genetic and in vitro expression analyses are useful for accurate genetic counseling for a family with a history of both CN-1 and CN-2.

Neonatal Meckel diverticulum: Obstruction due to a short mesodiverticular band.

This is the first report of symptomatic Meckel diverticulum in a newborn, in which direct compression by a short mesodiverticular band (MDB) caused intestinal obstruction. A short MDB can cause intestinal obstruction due to direct compression. There are two mechanisms by which Meckel diverticulum with MDB can cause intestinal obstruction: internal hernia and direct compression. Onset of intestinal obstruction due to direct compression by a short MDB might be earlier than that for internal hernia with long MDB.

Suspected fetal onset of neonatal transient eosinophilic colitis and development of respiratory distress.

Neonatal transient eosinophilic colitis (NTEC) is a new disease concept within eosinophilic gastroenteritis, which was proposed by Ohtsuka et al. It causes hematochezia as a result of eosinophilia, in neonates who have not yet started to receive enteral nutrition, although the whole-body status of the infant is in fact relatively good. To date, there have been no reports of this disease in which abnormalities were noted during gestation, and the clinical phenomena surrounding it, along with any complications, are not yet clear. We encountered a suspected case of NTEC causing respiratory distress with aspiration of hematochezia, in which dilated bowel was noted during gestation. This case indicates that NTEC may occur at the fetal stage and be complicated by respiratory distress.

Bilirubin uridine diphosphate-glucuronosyltransferase variation is a genetic basis of breast milk jaundice.

OBJECTIVE: To evaluate the role of bilirubin UDP-glucuronosyltransferase family 1, polypeptide A1 (UGT1A1) gene variations on prolonged unconjugated hyperbilirubinemia associated with breast milk feeding (breast milk jaundice [BMJ]). STUDY DESIGN: UGT1A1 gene allelic variation was analyzed in 170 Japanese infants with BMJ with polymerase chain reaction-direct sequencing, and their genotypes compared with serum bilirubin concentrations. In 62 of 170 infants, serum bilirubin concentration was followed after 4 months of life. Genotypes were examined in 55 infants without BMJ. RESULTS: Of 170 infants with BMJ, 88 (51.8%) were homozygous UGT1A1*6. Serum bilirubin concentrations (21.8 ± 3.65 mg/dL) were significantly greater than in infants with other genotypes (P < .0001). The Gilbert UGT1A1*28 allele was not detected in infants with BMJ, except in an infant who was compound heterozygous with UGT1A1*6. At 4 months of age, serum bilirubin concentration improved to >1 mg/dL, except in 2 infants who were homozygous UGT1A1*7. Homozygous UGT1A1*6 was not detected in the control group. CONCLUSION: One-half of the infants with BMJ were homozygous UGT1A1*6 and exhibited a serum bilirubin concentration significantly greater than other genotypes. This finding indicates that UGT1A1*6 is a major cause of BMJ in infants in East Asia. Previous finding have demonstrated that 5ß-pregnane-3α,20ß-diol present in breast milk inhibits p.G71R-UGT1A1 bilirubin glucuronidation activity. Thus, prolonged unconjugated hyperbilirubinemia may develop in infants with UGT1A1*6 who are fed breast milk.

Efficacy of bronchial fiberscope in esophageal fistula caused by necrotizing bronchitis.

Neonatal necrotizing bronchitis is a disease that occurs in premature and low-birthweight infants who are subject to artificial respiratory management, and which has a poor prognosis, because it progresses suddenly and can result in death. There have been no reports of survival to date in cases of tracheo-esophageal fistula caused by necrotizing bronchitis, and no swift and effective management method has yet been reported. This report describes a case in which the use of a bronchial fiberscope in making an early diagnosis facilitated appropriate management and survival. The proactive use of a bronchial fiberscope in regard to this disease, which has a high fatality rate, may save lives.

Hallopeau-Siemens dystrophic epidermolysis bullosa due to homozygous 5818delC mutation in the COL7A gene.

Epidermolysis bullosa (EB) is a group of inherited mechanobullous skin disease. The dystrophic EB (DEB), one subtype of EB, is inherited in an autosomal dominant DEB or in an autosomal recessive (RDEB). DEB is caused by mutations in the COL7A1 gene encoding type VII collagen, the major component of anchoring fibrils. Over 300 pathogenic mutations have been detected within COL7A in DEB. Patients with the Hallopeau-Siemens type (HS-RDEB), most severe form of DEB, frequently have premature termination codon (PTC) mutations on both alleles. PTC mutations on both alleles result in depleted mRNA and α1 helix, and failure to form the triple helix structure characteristic of type VII collagen. As patients with HS-RDEB usually have a pair of heterozygous PTC mutations, there have been rarely reported homozygous ones in HS-RDEB. We report the first case of HS-RDEB homozygous PTC mutations of 5818delC in both COL7A1 alleles. This case report suggests the positional effect of PTC mutations and vigilance against early infantile death in EB including HS-RDEB.