A Case of Hyperinsulinemic Hypoglycemia in Premature Infant Treated with Oral Diazoxide

Neonatal hyperinsulinism, whether permanent or transient, results in prolonged hypoglycemia, which increases the risk of hypoglycemic brain injury. Therefore, prompt diagnosis and management of hyperinsulinemic hypoglycemia is important. Drawing a “critical sample” at the time of hypoglycemia is useful for diagnosis. Genetic testing for defective insulin-regulating genes in pancreatic beta-cells might also be helpful in cases of prolonged hypoglycemia. High-calorie feeding or glucose infusion is necessary to maintain normoglycemia. Diazoxide is the treatment of choice for hyperinsulinism and should be continued until the hypoglycemia resolves. We describe a case of transient neonatal hyperinsulinemia hypoglycemia in a small-for-gestational-age preterm infant who underwent diazoxide treatment and achieved a favorable outcome.

A Case of Transient Neonatal Diabetes Mellitus Attributable to a Nonspecific Mutation in the ABCC8 Gene

Neonatal diabetes mellitus (NDM) is defined as hyperglycemia that persists for more than 2 weeks and requires insulin therapy. NDM principally occurs before 6 months of age. Transient NDM (TNDM) is a clinical form of NDM that persists for a median of 12 weeks and resolves completely by 18 months. However, it may relapse as type 2 DM during early adulthood. The major causes of TNDM are mutations in chromosome 6q24 or the KCNJ11 or ABCC8 genes; the latter encode the two subunits of the pancreatic adenosine triphosphate (ATP)-sensitive potassium channel (KATP-channel). This condition responds well to oral sulfonylurea therapy. Herein, we report a neonate who was small for gestational age and exhibited TNDM symptoms. Genetic analysis revealed a nonspecific mutation in ABCC8; he was successfully treated with oral sulfonylurea.

Perinatal Risk Factors for Postnatal Weight Loss in Late Preterm Infants

PURPOSE: Many studies have reported associations of early postnatal growth failure in preterm infants with several morbidities. However, the risk factors for postnatal weight loss (PWL) in late preterm infants have not been identified. We investigated the independentrisk factors for PWL in late preterm infants.METHODS: This was a retrospective cohort study. We enrolled 369 late preterm infants born at 34⁺⁰ to 36⁺⁶ weeks gestational age who were admitted to the Soonchunhyang University Cheonan Hospital between 2015 and 2017. PWL% was calculated as (birth weight–lowest weight)/birth weight×100. The infants were classified into lower (< 5%) and higher (≥10%) PWL% groups by propensity score matching for gestational age, sex, and birth weight. Perinatal risk factors were analyzed using multivariable logistic regression.RESULTS: The lower and higher PWL% groups included 62 and 31 infants, respectively. Antenatal steroids administered within 1 week before birth (odds ratio [OR], 3.26; 95% confidence interval [CI], 1.015 to 10.465; P=0.047), lower total calorie intake during days 1 to 7 (OR, 0.98; 95% CI, 0.977 to 0.999; P=0.027), and phototherapy (OR, 5.28; 95% CI, 1.327 to 21.024; P=0.018) were independent risk factors for the higher PWL%.CONCLUSION: Further studies are needed to identify the risk factors that cause high PWL% according to gestational age and short- and long-term morbidities based on the degree of PWL.

Transient intubation for surfactant administration in the treatment of respiratory distress syndrome in extremely premature infants / 소아과

PURPOSE: To investigate the effectiveness of transient intubation for surfactant administration and extubated to nasal continuous positive pressure (INSURE) for treatment of respiratory distress syndrome (RDS) and to identify the factors associated with INSURE failure in extremely premature infants. METHODS: Eighty-four infants with gestational age less than 28 weeks treated with surfactant administration for RDS for 8 years were included. Perinatal and neonatal characteristics were retrospectively reviewed, and major pulmonary outcomes such as duration of mechanical ventilation (MV) and bronchopulmonary dysplasia (BPD) plus death at 36-week postmenstrual age (PMA) were compared between INSURE (n=48) and prolonged MV groups (n=36). The factors associated with INSURE failure were determined. RESULTS: Duration of MV and the occurrence of BPD at 36-week PMA were significantly lower in INSURE group than in prolonged MV group (P < 0.05), but BPD plus death at 36-week PMA was not significantly different between the 2 groups. In a multivariate analysis, a reduced duration of MV was only significantly associated with INSURE (P=0.001). During the study period, duration of MV significantly decreased over time with an increasing rate of INSURE application (P < 0.05), and BPD plus death at 36-week PMA also tended to decrease over time. A low arterial-alveolar oxygen tension ratio (a/APO2 ratio) was a significant predictor for INSURE failure (P=0.001). CONCLUSION: INSURE was the noninvasive ventilation strategy in the treatment of RDS to reduce MV duration in extremely premature infants with gestational age less than 28 weeks.

Decolonization of Methicillin resistant Staphylococcus aureus: Role in the Neonatal Intensive Care Unit

PURPOSE: We aimed to assess the incidence of methicillin-resistant Staphylococcus aureus (MRSA) colonization and infection in a neonatal intensive care unit (NICU) by using various decolonization methods and to evaluate their efficacy. METHODS: Medical records of all neonates who were admitted to the NICU of Seoul National University Children's Hospital were retrospectively reviewed. Surveillance culture were obtained for all neonates in the NICU 48 hours after admission. Three periods with different decolonization methods were compared; Period 1 was without any decolonization measures (July 1, 2009 to August 26, 2010). In period 2, intranasal mupirocin and chlorhexidine gluconate bathing were administered to MRSA-colonized neonates (August 27, 2010 to September 6, 2011). In period 3, only chlorhexidine bathing was performed for MRSA-colonized infants (September 7, 2011 to August 31, 2012). RESULTS: A total of 1,378 infants were admitted to the NICU during the study period. Baseline demographic and clinical characteristics were similar among the 3 periods. The incidence of MRSA colonization per 1,000 patient-days was 6.27 for period 1, 7.02 for period 2, and 6.29 for period 3; however, these values were not significantly different. The incidence of MRSA infection was highest in period 3, with 0.69 cases per 1,000 patient-days; however, this finding was not significant. The MRSA infection/colonization ratio also did not differ significantly among the 3 study periods. CONCLUSION: Decolonization of MRSA in the NICU with the application of chlorhexidine gluconate bathing alone or in combination with intranasal mupirocin were not effective in decreasing the incidence of MRSA colonization and infection.

Characteristics of Bronchopulmonary Dysplasia in Very Low Birth Weight Infants according to the Timing of Dexamethasone Administration / 대한주산의학회잡지

PURPOSE: Corticosteroids has been used for treatment and prophylaxis of bronchopulmonary dysplasia (BPD) in preterm infants. However, administration of corticosteroids could be delayed due to its potential harmful effects on neurodevelopment. The aim of this study was to evaluate the adequate dexamethasone administration timing in very low birth weight infants. METHODS: Medical records of 56 VLBW infants who were admitted to neonatal intensive care unit of Seoul National University Children's Hospital and Seoul National University Bundang Hospital between January 2008 and September 2014 were collected retrospectively. Study population were divided into early administration group (dexamethasone administration before 4 weeks of postnatal days) and late administration group (after 4 weeks) and respiratory morbidities were compared between groups. RESULTS: There were no significant differences in clinical characteristics between early administration group (n=30) and late administration group (n=26). Respiratory severity score and oxygen needs at 7 days after birth and before administering dexamethasone were comparable. Extubation was done earlier postnatal days in early administration group. Incidence of severe BPD was higher in the late administration group. There was no significant difference in diagnosed with cerebral palsy (CP) at 12 months of corrected age. When adjusting for multiple risk factors, administration of dexamethasone 4 weeks after birth and severe of BPD showed a significant association (adjusted OR 17.14 [1.29-227.52], P=0.031). CONCLUSION: Administration of dexamethasone in order to minimize ventilator care and to reduce severe BPD might be done between 1 week and 4 weeks after birth in very low birth weight infants.

Clinical Features of Congenital Adrenal Insufficiency Including Growth Patterns and Significance of ACTH Stimulation Test

Congenital adrenal insufficiency is caused by specific genetic mutations. Early suspicion and definite diagnosis are crucial because the disease can precipitate a life-threatening hypovolemic shock without prompt treatment. This study was designed to understand the clinical manifestations including growth patterns and to find the usefulness of ACTH stimulation test. Sixteen patients with confirmed genotyping were subdivided into three groups according to the genetic study results: congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH, n=11), congenital lipoid adrenal hyperplasia (n=3) and X-linked adrenal hypoplasia congenita (n=2). Bone age advancement was prominent in patients with CAH especially after 60 months of chronologic age (n=6, 67%). They were diagnosed in older ages in group with bone age advancement (P<0.05). Comorbid conditions such as obesity, mental retardation, and central precocious puberty were also prominent in this group. In conclusion, this study showed the importance of understanding the clinical symptoms as well as genetic analysis for early diagnosis and management of congenital adrenal insufficiency. ACTH stimulation test played an important role to support the diagnosis and serum 17-hydroxyprogesterone levels were significantly elevated in all of the CAH patients. The test will be important for monitoring growth and puberty during follow up of patients with congenital adrenal insufficiency.

Central precocious puberty in a patient with X-linked adrenal hypoplasia congenita and Xp21 contiguous gene deletion syndrome

X-linked adrenal hypoplasia congenita is caused by the mutation of DAX-1 gene (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1), and can occur as part of a contiguous gene deletion syndrome in association with glycerol kinase (GK) deficiency, Duchenne muscular dystrophy and X-linked interleukin-1 receptor accessory protein-like 1 (IL1RAPL1) gene deficiency. It is usually associated with hypogonadotropic hypogonadism, although in rare cases, it has been reported to occur in normal puberty or even central precocious puberty. This study addresses a case in which central precocious puberty developed in a boy with X-linked adrenal hypoplasia congenita who had complete deletion of the genes DAX-1, GK and IL1RAPL1 (Xp21 contiguous gene deletion syndrome). Initially he was admitted for the management of adrenal crisis at the age of 2 months, and managed with hydrocortisone and florinef. At 45 months of age, his each testicular volumes of 4 mL and a penile length of 5 cm were noted, with pubic hair of Tanner stage 2. His bone age was advanced and a gonadotropin-releasing hormone (GnRH) stimulation test showed a luteinizing hormone peak of 8.26 IU/L, confirming central precocious puberty. He was then treated with a GnRH agonist, as well as steroid replacement therapy. In Korea, this is the first case of central precocious puberty developed in a male patient with X-linked adrenal hypoplasia congenita.

Central precocious puberty in a patient with X-linked adrenal hypoplasia congenita and Xp21 contiguous gene deletion syndrome

X-linked adrenal hypoplasia congenita is caused by the mutation of DAX-1 gene (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1), and can occur as part of a contiguous gene deletion syndrome in association with glycerol kinase (GK) deficiency, Duchenne muscular dystrophy and X-linked interleukin-1 receptor accessory protein-like 1 (IL1RAPL1) gene deficiency. It is usually associated with hypogonadotropic hypogonadism, although in rare cases, it has been reported to occur in normal puberty or even central precocious puberty. This study addresses a case in which central precocious puberty developed in a boy with X-linked adrenal hypoplasia congenita who had complete deletion of the genes DAX-1, GK and IL1RAPL1 (Xp21 contiguous gene deletion syndrome). Initially he was admitted for the management of adrenal crisis at the age of 2 months, and managed with hydrocortisone and florinef. At 45 months of age, his each testicular volumes of 4 mL and a penile length of 5 cm were noted, with pubic hair of Tanner stage 2. His bone age was advanced and a gonadotropin-releasing hormone (GnRH) stimulation test showed a luteinizing hormone peak of 8.26 IU/L, confirming central precocious puberty. He was then treated with a GnRH agonist, as well as steroid replacement therapy. In Korea, this is the first case of central precocious puberty developed in a male patient with X-linked adrenal hypoplasia congenita.