Hye Jung Cho

Respiratory viruses in neonates hospitalized with acute lower respiratory tract infections

The burden of respiratory syncytial virus (RSV) in neonates has not been clearly studied. The aims of this study were to determine the overall distribution of respiratory viruses in neonates hospitalized with acute lower respiratory tract infectiosns (ALRI) and to describe the clinical characteristics of RSV infections in these neonates.

A CASE OF POSTERIOR REVERSIBLE ENCEPHALOPATHY SYNDROME IN A CHILD WITH MYELODYSPLASTIC SYNDROME FOLLOWING ALLOGENIC BONE MARROW TRANSPLANTATION

Posterior reversible encephalopathy syndrome (PRES) is an uncommon but distinctive clinical–radiologic entity characterized by headache, seizures, visual disturbance, and altered mental function associated with reversible white matter edema affecting the posterior parietal and occipital lobes of the brain. Although PRES is caused by a variety of conditions, acute elevation of blood pressure, fluid retention, and treatment with immunosuppressive drugs and/or anti-neoplastic agents are the main causes. A few cases of PRES associated with hematopoietic stem cell transplantation (HSCT) in children have been reported. Early recognition of PRES and appropriate management are needed to reduce the risk of permanent neurologic disability. The authors report a case of PRES in a girl who received an HLA-identical sibling bone marrow transplantation for myelodysplastic syndrome to emphasize the importance of early recognition and institution of appropriate management of PRES during HSCT.

Variation between residents and attending staff interpreting radiographs to verify placement of nutrition access devices in the neonatal intensive care unit.

INTRODUCTION Although radiography is considered the standard for confirming the position of nutrition access devices, it is sometimes difficult to visualize their tips. The purpose of this study was to evaluate how well pediatric residents could confirm placement via radiography of feeding tubes and intravenous (IV) nutrition catheter support in a neonatal intensive care unit (NICU). METHODS Seventy radiographs in a NICU during May 2013 were retrospectively evaluated. Eight pediatric residents (mean NICU experience, 5 months; range, 0-12 months) recorded the location of feeding tubes and IV nutrition catheters and marked their tips on computerized radiographs. Consensus review of radiographs by a radiologist and a NICU expert using a picture archiving communication system monitor in a reading room served as the reference standard. Detection rates and correct tip localization percentages were evaluated. RESULTS Of the 70 neonates, 38 had nutrition access devices: orogastric tube (n = 36), oroduodenal tube (n = 4), or central venous catheter (CVC) (n = 8). Detection rates were 89.6% for orogastric tubes (range, 75.0%-100%), 90.6% for oroduodenal tubes (range, 50.0%-100%), and 46.9% for CVCs (range, 12.5%-75.0%). Percentage of correct tip localizations was 85.7% for orogastric tubes (range, 74.1%-100%), 86.2% for oroduodenal tubes (range, 25.0%-100%), and 70% for CVCs (range, 50.0%-100%). CONCLUSION It is not easy for pediatrician residents to confirm the position of nutrition access devices in neonates by using radiographs. Reinforcement of radiology teaching, second opinions from radiologists or NICU experts, and other methods for verifying the positions of nutrition access devices are needed to minimize complications.

Knockdown of PRKAR2B Results in the Failure of Oocyte Maturation

Background/Aims: Cyclic adenosine monophosphate (cAMP)-dependent type 2 regulatory subunit beta (Prkar2b) is a regulatory isoform of cAMP-dependent protein kinase (PKA), which is the primary target for cAMP actions. In oocytes, PKA and the pentose phosphate pathway (PPP) have important roles during the germinal vesicle (GV) stage arrest of development. Although the roles of the PKA signal pathway have been studied in the development of oocyte, there has been no report on the function of PRKAR2B, a key regulator of PKA. Methods: Using reverse transcription polymerase chain reaction (RT-PCR), quantitative real-time PCR (qRT-PCR), immunohistochemistry, and immunofluorescence, we determined the relative expression of Prkar2b in various tissues, including ovarian follicles, during oocyte maturation. Prkar2b-interfering RNA (RNAi) microinjection was conducted to confirm the effect of Prkar2b knockdown, and immunofluorescence, qRT-PCR, and time-lapse video microscopy were used to analyze Prkar2b-deficient oocytes. Results: Prkar2b is strongly expressed in the ovarian tissues, particularly in the growing follicle. During oocyte maturation, the highest expression of Prkar2b was during metaphase I (MI), with a significant decrease at metaphase II (MII). RNAi-mediated Prkar2b suppression resulted in MI-stage arrest during oocyte development, and these oocytes exhibited abnormal spindle formation and chromosome aggregation. Expression of other members of the PKA family (except for Prkaca) were decreased, and the majority of the PPP factors were also reduced in Prkar2b-deficient oocytes. Conclusion: These results suggest that Prkar2b is closely involved in the maturation of oocytes by controlling spindle formation and PPP-mediated metabolism.

Pattern of Hospital-Associated Infections in Children Admitted in the Intensive Care Unit of a University Hospital

Purpose : Hospital associated infection (HAI) caused by multidrug-resistant (MDR) microorganisms has been recognized as an important issue in the world, especially in critically ill patients such as the patients admitted in the intensive care unit. There are fewer papers about MDR-HAI in pediatric patients compared to adult patients. In this study, we investigated the incidence and associated factors of MDR-HAI in children admitted to the intensive care unit (ICU) of a university hospital. Methods : We retrospectively evaluated 135 children who were admitted in ICU for at least 3 days between January 2009 and December 2010. HAI cases were divided into MDR-HAI group and non-MDR-HAI group. Clinical characteristics and various associated factors were compared between those groups. Results : In 39 patients, 45 cases of ICU-related HAI were developed. ICU-related HAI incidence was 47.7 per 1000 patientdays. Thirty-six cases (80.0%) were MDR-HAI. Acinetobacter baumannii was isolated more commonly in MDR-HAI group. And the followings were found more frequently in MDR-HAI group than non-MDR-HAI group: medical condition as an indication for ICU admission, mechanical ventilation, urinary catheterization and previous use of broad-spectrum antibiotics. Among the risk factors, previous use of broad-spectrum antibiotics was the independent risk factor for MDR-HAI. Conclusion : ICU-related HAI incidence was higher than previously reported. Previous use of broad-spectrum antibiotics was the independent risk factor for MDR-HAI. To investigate the characteristics of MDR-HAI in children admitted in ICU, further studies with a larger sample size over a longer period of time are warranted.