Serum interleukin-18 level as a possible early diagnostic marker of systemic juvenile idiopathic arthritis.

Early diagnosis of systemic juvenile idiopathic arthritis (s-JIA) is a prerequisite for therapeutic efficacy. However, it is often challenging because most patients with s-JIA do not show arthritis at disease onset and are simply diagnosed with fever of unknown origin. Serum ferritin levels have commonly been used to diagnose s-JIA because they increase in patients with this condition by more than 5 times their normal value. However, there are no definite biomarkers for s-JIA, which makes the clinical diagnosis of s-JIA difficult. We report a case of s-JIA in which interleukin (IL)-18 elevation was observed before ferritin elevation at the early phase of s-JIA. We propose serum IL-18 levels as a more useful biomarker for the early diagnosis of s-JIA compared to serum ferritin levels.

Pharyngeal pressure due to high-flow nasal cannula devices in preterm infants.

BACKGROUND: In infants, a high-flow nasal cannula (HFNC) generates continuous positive pressure on the upper airway. This study aimed to evaluate the association between pharyngeal pressure and flow rate, and the association between pharyngeal pressure and bodyweight for two types of HFNC devices commonly used in preterm infants: the Optiflow Junior, hereafter "FP" (Fisher & Paykel, Auckland, New Zealand), and the Precision Flow, hereafter "VT" (Vapotherm, Exeter, NH, USA). METHODS: Pharyngeal pressure measurements were performed in 12 preterm infants who received HFNC support. Flow rates of 1 to 4 L/kg/min were studied. RESULTS: The median weight at the time of measurement was 1,290 g (range, 953-1,932 g). The FP was used in eight infants and the VT in four. In both of the groups, the flow rate and pharyngeal pressure appeared to be positively correlated except for the premature cannula in the FP group. At a flow rate of ≥2 L/kg/min, there was a positive correlation between the bodyweight and pharyngeal pressure in infants with premature and neonatal cannulas in the FP group. Conversely, at the same flow rate, there was a negative correlation between the bodyweight and pharyngeal pressure in infants with a SOLO cannula in the VT group. CONCLUSIONS: In preterm infants, the flow rate and pharyngeal pressure were positively correlated in many HFNC cannulas. However, the pharyngeal pressure and bodyweight appeared to be positively and negatively correlated in the FP and VT groups, respectively. Future studies with larger sample sizes should further investigate this issue.

A Novel Method for Measuring Serum Unbound Bilirubin Levels Using Glucose Oxidase-Peroxidase and Bilirubin-Inducible Fluorescent Protein (UnaG): No Influence of Direct Bilirubin.

The glucose oxidase-peroxidase (GOD-POD) method used to measure serum unbound bilirubin (UB) suffers from direct bilirubin (DB) interference. Using a bilirubin-inducible fluorescent protein from eel muscle (UnaG), a novel GOD-POD-UnaG method for measuring UB was developed. Newborn sera with an indirect bilirubin/albumin (iDB/A) molar ratio of <0.5 were classified into four groups of DB/total serum bilirubin (TB) ratios (<5%, 5-10%, 10-20%, and ≥20%), and the correlation between the UB levels and iDB/A ratio was examined. Linear regression analysis was performed to compare UB values from both methods with the iDB/A ratio from 38 sera samples with DB/TB ratio <5% and 11 samples with DB/TB ratio ≥5%. The correlation coefficient (r) between UB values and the iDB/A ratio for the GOD-POD method was 0.8096 (DB/TB ratio <5%, n = 239), 0.7265 (5-10%, n = 29), 0.7165 (10-20%, n = 17), and 0.4816 (≥20%, n = 16). UB values using the GOD-POD-UnaG method highly correlated with the iDB/A ratio in both <5% and ≥5% DB/TB ratio sera (r = 0.887 and 0.806, respectively), whereas a low correlation (r = 0.428) occurred for ≥5% DB/TB ratio sera using the GOD-POD method. Our GOD-POD-UnaG method can measure UB levels regardless of the presence of DB.

Evaluation index for asymmetric ventricular size on brain magnetic resonance images in very low birth weight infants.

OBJECTIVE: Asymmetric ventriculomegaly is often evident on brain magnetic resonance imaging (MRI) in very low birth weight infants (VLBWI) and is interpreted as white matter injury. However, no evaluation index for asymmetric left-right and anterior-posterior ventricular sizes has been established. METHODS: In this retrospective multicenter cohort study, brain T2-weighted MRI was performed at term-equivalent ages in 294 VLBWI born between 2009 and 2011. The value of a lateral ventricular index (LVI) to evaluate asymmetric ventricular size, as well as the relationship between the LVI value and walking at a corrected age of 18 months was investigated. At the level of the foramen of Monro in a horizontal slice, asymmetry between the left and right sides and between the anterior and posterior horns was identified by the corrected width and was detected by a low concordance rate and κ statistic value. An LVI representing the sum of the widths of the four horns of the lateral ventricle corrected for cerebral diameter was devised. RESULTS: Asymmetric left-right and anterior-posterior ventricular sizes were confirmed. The LVI value was significantly higher in the non-walking VLBWI group (n = 39) than in the walking VLBWI group (n = 255; 18.2 vs. 15.8, p = 0.02). An LVI cut-off value of 21.5 was associated with non-walking. Multivariate analysis revealed that an LVI value >21.5 was an independent predictor of walking disability at the corrected age of 18 months (odds ratio 2.56, p = 0.008). CONCLUSIONS: The LVI value calculated via MRI may predict walking disability at a corrected age of 18 months in VLBWI.

Heme Oxygenase-1 Expression Affects Murine Abdominal Aortic Aneurysm Progression.

Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme degradation, is a cytoprotective enzyme upregulated in the vasculature by increased flow and inflammatory stimuli. Human genetic data suggest that a diminished HO-1 expression may predispose one to abdominal aortic aneurysm (AAA) development. In addition, heme is known to strongly induce HO-1 expression. Utilizing the porcine pancreatic elastase (PPE) model of AAA induction in HO-1 heterozygous (HO-1+/-, HO-1 Het) mice, we found that a deficiency in HO-1 leads to augmented AAA development. Peritoneal macrophages from HO-1+/- mice showed increased gene expression of pro-inflammatory cytokines, including MCP-1, TNF-alpha, IL-1-beta, and IL-6, but decreased expression of anti-inflammatory cytokines IL-10 and TGF-beta. Furthermore, treatment with heme returned AAA progression in HO-1 Het mice to a wild-type profile. Using a second murine AAA model (Ang II-ApoE-/-), we showed that low doses of the HMG-CoA reductase inhibitor rosuvastatin can induce HO-1 expression in aortic tissue and suppress AAA progression in the absence of lipid lowering. Our results support those studies that suggest that pleiotropic statin effects might be beneficial in AAA, possibly through the upregulation of HO-1. Specific targeted therapies designed to induce HO-1 could become an adjunctive therapeutic strategy for the prevention of AAA disease.

Screening for Hyperbilirubinemia in Japanese Very Low Birthweight Infants Using Transcutaneous Bilirubinometry.

OBJECTIVES: To assess the accuracy of transcutaneous bilirubin (TcB) measurements at 5 different body sites in Japanese very low birthweight (VLBW) infants and to determine a cut-off value of TcB to detect total serum/plasma bilirubin (TB) levels ≥10 mg/dL (171 µM). STUDY DESIGN: In a prospective multicenter study, 85 Japanese VLBW infants were enrolled from 5 neonatal intensive care units during the study period. A total of 383 blood samples from infants not receiving phototherapy or ≥24 hours postphototherapy were analyzed. TcB was measured at the forehead, sternum, upper back, lower abdomen, and waist within 1 hour of blood collection. Linear regression analysis and Bland-Altman plots were used to compare TcB values at each site with TB levels. The TcB cut-off value for detecting TB ≥10 mg/dL was determined by receiver operating characteristics curve analysis. RESULTS: TcB significantly correlated with TB, but the coefficient of determination varied among the sites (forehead: 0.5294, sternum: 0.6488, upper back: 0.6321, lower abdomen: 0.5430, waist: 0.7396). At a TcB value ≥8, the sensitivity was 100% at the sternum and upper back, 85% at the waist, 84% at the forehead, and 64% at the lower abdomen to detect TB ≥10 mg/dL. CONCLUSIONS: In Japanese VLBW infants, the accuracy of TcB measurements varies according to body site. TcB ≥8 on the sternum or upper back is more reliable than that on the forehead, lower abdomen, or waist to detect TB levels ≥10 mg/dL.

Serum unbound bilirubin as a predictor for clinical kernicterus in extremely low birth weight infants at a late age in the neonatal intensive care unit.

BACKGROUND: This study aimed to evaluate peak serum total bilirubin (TB) and unbound bilirubin (UB) levels in preterm infants with clinical kernicterus (KI) who were diagnosed by clinical findings during infancy. DESIGN/SUBJECTS: For this multicenter retrospective study, 18 Japanese extremely low birth weight (ELBW) infants with clinical KI were included. Clinical KI was diagnosed based on the presence of motor developmental impairment with/without athetosis, and abnormal magnetic resonance imaging or brainstem auditory evoked potential findings during infancy. High and low TB or UB levels were defined as serum TB levels ⩾ and <15 mg/dL or serum UB levels ⩾ and <0.8 µg/dL, respectively. The clinical characteristics of KI preterm infants were analyzed. The proportion of infants with high or low serum TB levels and with high or low serum UB levels was then investigated. Sensitivity and specificity were calculated. RESULTS: In 18 KI infants, the median age when serum TB levels peaked was 28 days after birth. In eight KI infants with low serum TB levels, 88% of them had high serum UB levels. For comparison of the number of infants who had high or low serum TB and UB levels, the sensitivity was 90% and specificity was 13%. CONCLUSIONS: Serum TB and UB levels peak at a later age than expected. Chronic serum UB monitoring may be helpful for identifying ELBW infants at risk for developing KI, even when they do not have high serum TB levels.

Serial assessment of right ventricular function using tissue Doppler imaging in preterm infants within 7 days of life.

BACKGROUND: We aimed to evaluate right ventricular (RV) function longitudinally using tissue Doppler imaging (TDI) echocardiography in preterm infants. METHODS: We selected 101 very-low-birth-weight (VLBW) infants for the study. Echocardiographic examinations including TDI were performed serially within 7days of life. Pulsed-Doppler TDI waveforms were recorded at the tricuspid valve annulus, and peak systolic velocities (Sa), early diastolic velocities (Ea), and late diastolic velocities (Aa) were measured. RESULTS: Sa, Ea and Aa were all reduced significantly from 3h to 12h, and then increased gradually thereafter. These three velocities also increased with gestational age in the early neonatal period. The ratio of Ea to Aa (Ea/Aa) did not change significantly within the first week of life. The ratio of E to Ea (E/Ea) in VLBW infants also seemed to remain stable from birth to day 7. The values of Sa appeared to be associated with cardiac output in the early neonatal period. Both Sa and Aa in intubated infants were significantly higher than in non-intubated infants. CONCLUSION: RV TDI velocities of preterm infants in the early neonatal period are influenced by gestational age, postnatal age, and respiratory status, although the RV E/Ea ratio appears to be almost stable throughout the neonatal period. Our findings may provide some basis for assessment of RV function in critically ill preterm infants.

[The diagnostic performance of color Doppler ultrasonography for newborn four cases of midgut volvulus accompanied by intestinal malrotation].

Midgut volvulus accompanied by intestinal malrotation is classified as a surgical emergency disease of the newborn, which emerges with the bilious vomiting or melena. This report presents four patients of this disease in our hospital, evaluated by color Doppler ultrasonography before surgical operation. All four patients were presented by bilious vomiting at the onset. By color Doppler ultrasonography method, the whirlpool sign which is the view of intestine and superior mesenteric vein rotated around with the axis of superior mesenteric artery, were shown in all cases. This whirlpool sign led to the diagnosis of midgut volvulus accompanied by intestinal malrotation. Intestinal contrast imaging was tested in three patients for the purpose of confirming the diagnosis. Repair of the volvulus and a ladd operation was performed in all four patients, without the excision of intestine because of no intestinal ischemic change. The clinical courses of four cases were good, and all patients were discharged within 17 days. Early diagnosis and timely surgical operation are essential for decreasing the possibility of occurring intestinal ischemic changes and improving clinical outcome after surgical operation. We propose that color Doppler ultrasonography is the powerful tool for the diagnosis of this disease, especially for the newborn, for whom the available diagnostic tests are limited.

Serial assessment of left-ventricular function using tissue Doppler imaging in premature infants within 7 days of life.

Although many echocardiographic parameters can assess cardiac function noninvasively in preterm infants, it has not been determined what indices are the best. We assessed left-ventricular performance in 101 very low-birth weight (VLBW) infants using tissue Doppler imaging (TDI) echocardiography. Echocardiographic examinations, including TDI, were performed serially within 7 days of life. Pulsed-Doppler TDI waveforms were recorded at the mitral valve annulus, and peak systolic velocities (Sa), early diastolic velocities (Ea), and late diastolic velocities (Aa) were measured. Sa and Aa velocities were both decreased significantly from 3 to 12 h and then gradually increased. Ea velocities showed no significant, longitudinal changes, but Ea values in premature groups appeared to be significantly lower than those in mature groups. The ratio of E to Ea (E/Ea) of VLBW infants seemed to be almost stable from birth to day 7, and this also showed no significant differences between different gestational age groups. E/Ea values in infants with patent ductus arteriosus (PDA) appeared to be greater than those in non-PDA infants. Our present findings suggest that TDI assessment in the early neonatal period might be useful in detecting latent systolic/diastolic failure of critically ill preterm infants.

Novel treatment strategy for Japanese newborns with high serum unbound bilirubin.

BACKGROUND: Serum unbound bilirubin (UB) is a measure of bilirubin not bound to albumin, and has been reported to be better than total bilirubin level at identifying infants at risk of developing bilirubin-induced neurotoxicity, including auditory abnormalities. A detailed treatment strategy for newborns with high serum UB has not been established. The aim of this study was to assess auditory outcomes in newborns with serum UB ≥1.00 µg/dL who were treated according to a novel treatment protocol. METHODS: A prospective clinical study was conducted in newborns weighing >1500 g with serum UB ≥1.00 µg/dL who were admitted to Kobe University Hospital and Kakogawa Municipal Hospital, Japan from 2006 to 2011. Enrolled newborns were treated as follows: (i) if serum UB was 1.00-1.50 µg/dL, phototherapy and infusion were given with or without albumin or immunoglobulin therapy; and (ii) if serum UB was >1.50 µg/dL, exchange transfusion was performed immediately. Auditory brainstem responses were evaluated at the time of discharge. RESULTS: A total of 89 Japanese newborns with UB ≥1.00 µg/dL were enrolled at a median age of 4 days. Of these, 85 had UB 1.00-1.50 µg/dL and four had UB >1.50 µg/dL. After being treated according to the protocol, no newborns were diagnosed with auditory brainstem response abnormalities. CONCLUSIONS: The present treatment protocol for Japanese newborns with serum UB ≥1.00 µg/dL may be useful for the prevention of bilirubin-induced auditory abnormalities.

Left and right ventricular myocardial performance index (Tei index) in very-low-birth-weight infants.

This study presents a report of serial assessment of ventricular myocardial performance index (Tei index) in very-low-birth-weight (VLBW) infants. One hundred ninety-five VLBW infants, weighing <1,500 g, who were admitted to the neonatal intensive care units at Kakogawa Municipal Hospital between September 2000 and August 2004. Left ventricular (LV) and right ventricular (RV) Tei indexes were assessed consecutively from birth to day 28 in all VLBW infants using pulsed-Doppler echocardiography. The mean values of the LV Tei index rose rapidly from 3 to 12 h after birth and then fell significantly after 24 h. Those of the RV Tei index increased slightly from 3 to 12 h, then decreased drastically after 24 h. The LV Tei index was found to correlate inversely with LV output and LV ejection fraction in the early neonatal period, while the relationship between the LV Tei index and the LV E/A velocity ratio was not significant. The RV Tei index was inversely correlated with RV output. In conclusion, both of the ventricular Tei indexes in VLBW infants showed drastic and significant changes on the first to second day after birth.

A novel diagnostic tool for detecting neonatal infections using multiplex polymerase chain reaction.

BACKGROUND: In newborns with infections, it is necessary to detect various pathogens rapidly and accurately, because the infections are often fatal when diagnosis is delayed. However, no diagnostic tools that rapidly detect pathogens causing neonatal infectious diseases are available. OBJECTIVES: To establish a rapid diagnostic tool using multiplex polymerase chain reaction (PCR) to detect 8 major pathogens that often cause neonatal infections, including Group B Streptococcus, Escherichia coli, Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, Ureaplasma urealyticum, herpes simplex virus, Cytomegalovirus, and Candida albicans, and to validate this tool in the neonatal intensive care unit (NICU). METHODS: One hundred and thirty clinical samples were obtained from newborns with any infectious signs or histories. DNA was extracted from these samples and multiplex PCR was performed with a mixture of 8 primer pairs, all designed to amplify pathogenic DNA and produce different sizes of amplicons. Seventy-seven samples with suspicion of bacterial infections were also examined by bacterial culture to evaluate the accuracy of the multiplex PCR results. RESULTS: Six of the 8 pathogens could be rapidly detected by our multiplex PCR method, within 3.5-4.5 h. These positive results led us to immediately diagnose and select proper drugs against each pathogen. In comparison with culture results, our test characteristics were as follows: specificity: 93%, negative predictive value: 96%, and concordance rate: 90%. CONCLUSIONS: We have established and validated a rapid diagnostic tool for detecting pathogens using multiplex PCR, which may be useful for the confirmed diagnosis of neonatal infections in the NICU.

Inhibition of heme oxygenase activity in newborn mice by azalanstat.

Inhibition of heme oxygenase (HO), the rate-limiting enzyme in heme catabolism, may be an ideal strategy for preventing neonatal jaundice. Although natural and synthetic heme analogs, called metalloporphyrins (Mps), have been extensively investigated for this purpose, some Mps are phototoxic, affect the activity of other enzymes, or induce HO-1 transcription-properties that may limit their clinical use. Another class of compounds, imidazole-dioxolanes, has been shown to selectively inhibit the inducible isozyme HO-1. Therefore, we investigated the efficacy of azalanstat (AZA), an imidazole-dioxolane, towards inhibiting HO activity in 7-day-old mice. We found that a single dose of AZA at 500 micromol.kg(-1) body mass (BM) administered i.p. significantly inhibited HO activity and reduced in vivo bilirubin production. In the spleen, HO inhibition (>50%) was observed within 0.25-3 h after administration. After 24 h, however, spleen HO activity, HO-1 protein, and HO-1 mRNA levels significantly increased 1.2-, 2.4-, and 4.0-fold, respectively. We conclude that AZA effectively inhibits in vivo HO activity only at a high dose and that it also induces spleen HO-1 gene transcription. Therefore, other imidazole-dioxolanes should be evaluated to determine whether they are more potent than AZA for use in treating neonatal jaundice.

Ureaplasma urealyticum and Mycoplasma hominis presence in umbilical cord is associated with pathogenesis of funisitis.

Ureaplasma urealyticum (U. urealyticum) and Mycoplasma hominis (M. hominis) are known to cause an intrauterine infection for preterm deliveries, but it is not known whether they are actually pathogenically involved in the development of funisitis, chorioamnionitis (CAM), and chronic lung disease (CLD) in preterm infants. Our purpose was to identify U. urealyticum and M. hominis in the umbilical cord, placenta, and tracheal aspirate (TA) or gastric fluid (GF) of preterm infants, and to clarify whether they contribute to funisitis, CAM, and CLD. Of 128 preterm infants, 86 umbilical cords, 83 placentas, and 84 TA or GF samples obtained postnatally from preterm infants were examined. U. urealyticum and M. hominis were detected by polymerase chain reaction and prospectively analyzed to determine whether the presence of U. urealyticum or M. hominis can lead to the development of funisitis, CAM, and CLD. U. urealyticum or M. hominis was isolated in nine (10.5%) of the umbilical cords, five (6.0%) of the placentas, and fifteen (17.9%) of the TA or GF samples. Funisitis was identified in all umbilical cords with U. urealyticum or M. hominis, but in only 13% of the umbilical cords without U. urealyticum and M. hominis (p < 0.001). Placentas and TA or GF with or without U. urealyticum and M. hominis did not show significant differences with regard to the development of CAM or CLD. Our results suggest that U. urealyticum and M. hominis presence is associated with the pathogenesis of funisitis, but not of CAM or CLD.

Quantification of lysophosphatidylcholines and phosphatidylcholines using liquid chromatography-tandem mass spectrometry in neonatal serum.

We established an improved method for quantification of phosphatidylcholine (PC) and lysophosphatidylcholine (LPC) molecular species in neonatal serum using high-performance liquid chromatography coupled tandem mass spectrometry (LC-MS/MS). A multiple reaction monitoring (MRM) mode of positive ionization for MS/MS was used. The method involved purification of phospholipids by solid phase extraction (SPE) from a 20-microl minimum specimen of serum. The assayed values of authentic 16:0-LPC and 18:0-LPC showed a linear response, and our quantitative results showed high precision for the all species of PC and LPC. Then, we quantified PC and LPC in adult and neonatal serum and compared them. Day 0-1 neonatal serum 16:0-, 18:0-, 18:1-, 18:2-LPC levels were significantly lower than adult ones. All species LPC levels in the day 0-1 neonates were significantly lower than day 4-8 neonates. Day 0-1 neonatal serum 16:0/18:2-, 18:0/18:2-PC levels were significantly lower than adult ones. Our method is advantageous for precise assessments of the relationships between PCs/LPCs levels and neonatal infectious diseases.

Novel double-deletion mutations of the OFD1 gene creating multiple novel transcripts.

Oral-facial-digital syndrome type 1 (OFD1) is an X-linked dominant disease characterized by malformations of the face, oral cavity, and digits. Thus far, 18 small mutations in the OFD1 gene have been reported. Here, we describe, in one Japanese sporadic female OFD1 case, the presence of a novel pair of deletion mutations: a 4,094-bp deletion encompassing exon 7 to intron 9, and a 14-bp deletion in intron 9, both of which are present in her paternal X-chromosome. The first deletion, the largest known to affect OFD1, was revealed by identifying four novel transcripts that all lacked exons 7-9. The most likely cause of the double deletion is two unequal recombinations between homologous sequences. Identification of the 4,094-bp deletion was made possible only by analyzing OFD1 mRNA, underscoring the utility of mRNA analysis in the mutational analysis of OFD1.