A Korean male with Kleefstra syndrome presented with micropenis.

Kleefstra syndrome is caused by chromosome 9q34.3 deletion or heterozygous mutations in the euchromatin histone methyl transferase 1 (EHMT1) gene. It can be accompanied by intellectual disability, distinctive facial features, microcephaly, psychiatric disorders, hypotonia in childhood, hearing loss, heart defects, renal defects, epilepsy, speech anomalies, and obesity. Furthermore, genital anomalies are present in 30%-40% of male patients with Kleefstra syndrome, but their mechanisms have not been elucidated. Herein, we report a patient with Kleefstra syndrome presenting with micropenis. The patient was transferred to Kyungpook National University Children's Hospital for management of imperforate anus on the day of birth. Physical examination revealed micropenis with stretched penile length of 0.9 cm and facial dysmorphisms, including hypertelorism and anteverted nares. Chromosomal microarray revealed 424-kb heterozygous deletion at chromosome 9q34.3 (arr[hg19] 9q34.3 (140,234,315-140,659,055)x1). Among the involved main OMIM genes, phenotypically relevant genes were EHMT1 and NSMF. Endocrinological investigation showed low basal gonadotropin and testosterone levels. Anterior pituitary hormones and steroid hormone levels were in the normal range. Testicular function was normal based on human chorionic gonadotropin stimulation test. The patient experienced improvement in penile length growth with intramuscular testosterone enanthate injection initiated at 4 months of age. The purpose of this study is to describe the etiology, endocrine laboratory tests, and treatment of micropenis in Kleefstra syndrome.

A novel compound variant in GNRHR causing congenital idiopathic hypogonadotropic hypogonadism in a young male Korean patient.

Idiopathic hypogonadotropic hypogonadism (IHH) is a disease that shows symptoms of no or incomplete sexual maturation after 18 years old. The mutation of gonadotropin releasing hormone receptor gene (GNRHR) has been reported as the cause in 16% of total IHH patients. An 18-year-old adolescent was referred to endocrinology department for hypogonadism. He was born with cryptorchidism, had small testes at the age of 7 years, and showed low testosterone levels. Management of his hypogonadism was delayed due to his uncontrolled nephrotic syndrome. There were no abnormal findings on the brain MRI; atrophied testes discovered on his pelvis MRI; low levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone were observed. In the HCG simulation test, testosterone levels showed no significant increase, rising from 1.11 to 1.15 ng/dL. The patient harbored a novel compound heterozygous variant of c.514G>A (p.Gly172Arg) and c.113G>A (p.Arg38Gln) in the GNRHR gene. Here, we report a case of new GNRHR compound variant c.514G>A (p.Gly172Arg) and c.113G>A (p.Arg38Gln) in a Korean adolescent for hypogonadotropic hypogonadism.

Metanephrine Negative Pheochromocytoma: A rare case report of dopamine-secreting tumor in an adolescent patient with NF1.

Pheochromocytoma (PCC) occurs in 4% of pediatric neurofibromatosis type 1 (NF1) patients and is mostly characterized by epinephrine and norepinephrine secretion. Herein, we report the first case of a dopamine-secreting PCC in a 13-year-old patient with NF1, in whom a left adrenal mass was incidentally found on abdominal computed tomography (CT) during hypertension workup. Fractionated 24-h urine metanephrine excretion was normal but urine dopamine level was elevated. On 123I-metaiodobenzylguanidine (MIBG) single photon emission tomography/CT (SPECT/CT), focal MIBG uptake was observed. Our multidisciplinary team determined that surgery would be difficult to perform because the tumor was small and the symptoms were vague, with only increased dopamine level. After six months, the tumor increased in size on abdominal CT, with focal significant uptake of the lesion on 6-[18F]fluoro-L-3,4-dihydroxyphenylalanine (18F-FDOPA) PET/CT. Laparoscopic resection was performed, and the mass was histologically confirmed as PCC. Currently, the vital signs of the patient are stable, urine dopamine levels are normal, and there is no abnormal uptake of 18F-FDOPA PET/CT. This study reports a case of a rare dopamine-secreting PCC. When metanephrine is negative in patients at high risk of PCC, focused examination and multidisciplinary approach are needed.

Metabolic Impacts of Discontinuation and Resumption of Recombinant Human Growth Hormone Treatment during the Transition Period in Patients with Childhood-Onset Growth Hormone Deficiency.

BACKGROUND: Discontinuing growth hormone (GH) treatment during the transition to adulthood has been associated with adverse health outcomes in patients with childhood-onset growth hormone deficiency (CO-GHD). This study investigated the metabolic changes associated with interrupting GH treatment in adolescents with CO-GHD during the transition period. METHODS: This study included 187 patients with CO-GHD who were confirmed to have adult GHD and were treated at six academic centers in Korea. Data on clinical parameters, including anthropometric measurements, metabolic profiles, and bone mineral density (BMD) at the end of childhood GH treatment, were collected at the time of re-evaluation for GHD and 1 year after treatment resumption. RESULTS: Most patients (n=182, 97.3%) had organic GHD. The median age at treatment discontinuation and re-evaluation was 15.6 and 18.7 years, respectively. The median duration of treatment interruption was 2.8 years. During treatment discontinuation, body mass index Z-scores and total cholesterol, low-density lipoprotein, and non-high-density lipoprotein (HDL) cholesterol levels increased, whereas fasting glucose levels decreased. One year after GH treatment resumption, fasting glucose levels, HDL cholesterol levels, and femoral neck BMD increased significantly. Longer GH interruption (>2 years, 60.4%) resulted in worse lipid profiles at re-evaluation. The duration of interruption was positively correlated with fasting glucose and non-HDL cholesterol levels after adjusting for covariates. CONCLUSION: GH treatment interruption during the transition period resulted in worse metabolic parameters, and a longer interruption period was correlated with poorer outcomes. GH treatment should be resumed early in patients with CO-GHD during the transition period.

Increase in blood glucose level and incidence of diabetic ketoacidosis in children with type 1 diabetes mellitus in the Daegu-Gyeongbuk area during the coronavirus disease 2019 (COVID-19) pandemic: a retrospective cross-sectional study.

BACKGRUOUND: The coronavirus disease 2019 (COVID-19) outbreak in the Daegu-Gyeongbuk area in 2020 has caused difficulties in the daily life and hospital care of children with type 1 diabetes mellitus (T1DM). We detected an increase in blood sugar levels in these children and the number of patients hospitalized with more severe diabetic ketoacidosis (DKA) compared to those before COVID-19. METHODS: This single-center study was conducted at Kyungpook National University Children's Hospital. The following patient groups were included; 45 returning patients diagnosed with T1DM and undergoing insulin treatment for more than 2 years and 20 patients newly diagnosed with T1DM before and after COVID-19 were selected by age matching. Returning patients before and after the outbreak were selected, and changes in hemoglobin A1c (HbA1c) levels were retrospectively reviewed. The HbA1c levels and severity of symptoms in newly diagnosed patients during hospitalization were examined. RESULTS: HbA1c levels in returning patients with T1DM were significantly increased after COVID-19 (before, 7.70%±1.38% vs. after, 8.30%±2.05%; p=0.012). There were 10 and 10 newly diagnosed patients before and after COVID-19, respectively. The proportion of patients with drowsiness and dyspnea at the time of admission was higher after COVID-19 than before (before, 2 of 10 vs. after, 4 of 10). The HbA1c levels were higher in newly diagnosed patients hospitalized after COVID-19 than before (before, 11.15% vs. after, 13.60%; p=0.036). CONCLUSION: Due to COVID-19 in the Daegu-Gyeongbuk area, there was an increase in blood glucose levels in children with T1DM and in the incidence of severe DKA in newly diagnosed diabetes mellitus patients.

Longitudinal Changes in Serum Creatinine Levels and Urinary Biomarkers in Late Preterm Infants during the First Postnatal Week: Association with Acute Kidney Injury and Treatment with Aminoglycoside.

We aimed to determine the incidence of acute kidney injury (AKI) and longitudinal changes in SCr levels and urinary biomarkers associated with AKI and aminoglycoside (AG) medication during the first week of life of late preterm infants. Urine biomarkers and SCr were measured in thirty late preterm infants on days one, two, five, and seven postnatal. Urine biomarkers included neutrophil gelatinase-associated lipocalin (NGAL), monocyte chemotactic protein-1 (MCP-1), epidermal growth factor (EGF), Tamm-Horsfall glycoprotein (THP), and liver fatty-acid-binding protein (L-FABP). Gestational age was positively correlated with SCr levels at birth, but inversely correlated with SCr levels at day five and day seven. Eighteen (60%) infants had stage 1 AKI, and twenty (67%) infants were treated with AGs. Infants with AKI had lower gestational age and lower birth weight than those without AKI. Urinary biomarkers adjusted according to uCr levels in infants with AKI were not statistically different from those in infants without AKI. There were no significant differences in incidence of AKI, and SCr levels during and after cessation of AG treatment. The uMCP-1/Cr ratio at days five and seven was higher in infants treated with AG than in non-treated infants.

Precocious puberty in Korean girls with and without exposure to endocrine-disrupting chemicals in toy slime: a comparative analysis.

BACKGROUND: Toy slime is popular in Korea, and in parallel, pre-pubertal girls visit hospitals for early pubertal signs. Thus far, numerous studies have investigated the association of endocrine-disrupting chemicals (EDCs) with precocious puberty (PP). However, there is a lack of studies on the clinical manifestations and sex hormones. We aimed to investigate early pubertal development in Korean girls with or without a history of toy slime exposure and determine changes in bone age, Tanner stage, and sex hormones. METHODS: In this study, 140 girls underwent stimulation tests at Kyungpook National University Children's Hospital Endocrinology Department, during January 2018 and December 2020. Patients were divided into two groups for gonadotropin-releasing hormone (GnRH) stimulation test and frequency of exposure to toy slime (EDCs). GnRH stimulation test was conducted after an intravenous injection of 100 µg of luteinizing hormone-releasing hormone. Slime exposure was defined as Slime ≥ 3 times/week for ≥ 3 months. RESULTS: History of slime exposure was found in 14 of 58 and 65 of 82 patients in the central PP (CPP) and non-CPP groups, respectively. Slime-exposed patients had advanced bone age, although their Tanner stage was low. Patients with a history of toy slime exposure were 5.5 times more likely to be diagnosed with non-CPP than patients without slime exposure (p < 0.05). CONCLUSIONS: Exposure to toy slime in prepubertal girls may be associated with rapid clinical advancement of pubertal development and bone age, and the patients appear more likely to be diagnosed with non-CPP.

Vitamin D Status and Factors Associated with Vitamin D Deficiency during the First Year of Life in Preterm Infants.

We aimed to investigate the changes in vitamin D levels and factors associated with vitamin D deficiency (VDD) during the first year of life in Korean preterm infants. We enrolled 333 preterm infants who were born at Kyungpook National University Children's Hospital between March 2013 and December 2019. 25-hydroxyvitamin D (25-OHD) levels and medical records were collected at birth, 6 months, and 12 months of age. The mean gestational age was 33.4 ± 2.3 weeks and mean 25-OHD levels at birth were 18.2 ± 13.5 ng/mL. The incidence of VDD was 82.8%, 30.6%, and 27.0% at birth, 6 months, and 12 months, respectively. The incidence of severe VDD (25-OHD < 10 ng/mL) was 31.5%, 1.5%, and 0%, at birth, 6 months, and 12 months, respectively. Among infants with severe VDD, the deficiency persisted in 49.6% at 6 months, and 35.3% at 12 months. The strongest predictor of VDD during follow-up was 25-OHD concentration at birth. Vitamin D supplementation at 400 IU/day did not affect vitamin D levels during the first year of life. Therefore, it is important to prevent neonatal VDD through maternal vitamin D supplementation during pregnancy. Further research is needed to determine the optimal vitamin D supplementation dose for Korean preterm infants.

Case report of compound CFTR variants in Korean siblings with cystic fibrosis: importance of differentiating cystic fibrosis from inflammatory bowel disease.

The prevalence of cystic fibrosis (CF) is considerably lower in Asian populations compared with that of Caucasians. Cases of CF are typically due to mutations in the CF transmembrane conductance regulator gene with autosomal recessive inheritance. Here, we report two cases of newly diagnosed CF in Korea-a 13-year-old boy and his 5-year-old brother. The older brother was admitted to our hospital for evaluation and treatment of recurrent abdominal pain, frequent diarrhea, and failure to thrive. Fecal calprotectin (FC) was elevated, and when combining this with his clinical presentation, inflammatory bowel disease (IBD) or eosinophilic gastroenteritis (EoGE) was the first impression of his disease. Several ulcerative lesions were observed on ileocolonoscopy. However, incidental findings of suspicious bronchiectatic lesions were observed on plain radiography, which were confirmed by chest computed tomography. Moreover, diffuse bowel wall thickening with pancreatic atrophy was also incidentally detected by computed tomography of the abdomen. Comprehensively, these findings were highly suggestive of CF. Therefore, diagnostic exome sequencing was conducted, which revealed compound heterozygous variants of c.263T>G (p.Leu88*) and c.2977G>T (p.Asp993Tyr) in the CF transmembrane conductance regulator gene. Although symptoms in the younger brother were not as prominent as the older brother, genetic test was also conducted, which revealed the same mutation. We report the identification of a novel variant, p.Asp993Tyr, in siblings with Korean heritage. Although CF is rare in Koreans, it should be included in the differential diagnosis of IBD.

A cell function study on calcium regulation of a novel calcium-sensing receptor mutation (p.Tyr825Phe).

PURPOSE: Autosomal dominant hypocalcemia with hypercalciuria is a genetic disease characterized by hypoparathyroidism with hypercalciuria. We discovered a novel variant (p.Tyr825Phe[Y825F]) of the CASR gene in a neonate with congenital hypoparathyroidism and hypercalciuria and conducted a cell function study to determine whether the CASR-Y825F variant was pathogenic. METHODS: To perform a functional study on CaSR-Y825F, we constructed expression vectors expressing wild-type (WT) CASR and CASR-Y825F. After transfection of each expression vector into HEK293 cells, we examined alterations in intracellular signaling. Mitogen-activated protein kinase (MAPK) signaling activity of HEK293 cells expressing CASR-WT or CASR-Y825F was determined. Changes in intracellular calcium ions ([Ca2+]i) by extracellular calcium ion ([Ca2+]e) stimulation were quantitatively compared and analyzed. RESULTS: Cells expressing CASR-Y825F showed elevated of MAPK signaling (phospho-ERK [pERK], phospho-JNK [pJNK], phospho-p38 [pp38]) and increased [Ca2+]i levels at low [Ca2+]e stimulation compared with cells expressing CASR-WT. Additionally, [Ca2+]i levels in HEK293 cells expression CASR-WT and CASR-Y825F were determined at 340 nm/380 nm wavelength ratios using Fura-2 AM. At [Ca2+]e concentrations of 2.5 mM and 3 mM, the ratios of CASR-Y825F cells were higher (2.6 and 3.5, respectively) than those of CASR-WT cells (1.04 and 1.40, respectively). CONCLUSION: This cell function study proved that the CASR-Y825F expressed in HEK293 cells elevated MAPK signaling (pERK, pJNK, pp38) and increased [Ca2+]i to induce hypocalcemia.

Clinical, endocrinological, and molecular features of four Korean cases of cytochrome P450 oxidoreductase deficiency.

PURPOSE: Cytochrome P450 oxidoreductase (POR) deficiency is a rare autosomal recessive disorder caused by mutations in the POR gene encoding an electron donor for all microsomal P450 enzymes. It is characterized by adrenal insufficiency, ambiguous genitalia, maternal virilization during pregnancy, and skeletal dysplasia. In this study, we investigated the clinical, hormonal, and molecular characteristics of patients with POR deficiency in Korea. METHODS: This study included four patients with POR deficiency confirmed by biochemical and molecular analysis of POR. Clinical and biochemical findings were reviewed retrospectively. Mutation analysis of POR was performed by Sanger sequencing after polymerase chain reaction amplification of all coding exons and the exon-intron boundaries. RESULTS: All patients presented with adrenal insufficiency and ambiguous genitalia regardless of their genetic sex. Two patients harbored homozygous p.R457H mutations in POR and presented with adrenal insufficiency and genital ambiguity without skeletal phenotypes. The other two patients with compound heterozygous mutations of c.[1329_1330insC];[1370G>A] (p.[I444Hfs*6];[R457H]) manifested skeletal abnormalities, such as craniosynostosis and radiohumeral synostosis, suggesting Antley-Bixler syndrome. They also had multiple congenital anomalies involving heart, kidney, and hearing ability. All patients were treated with physiologic doses of oral hydrocortisone. CONCLUSION: We report the cases of 4 patients with POR deficiency identified by mutation analysis of POR. Although the study involved a small number of patients, the POR p.R457H mutation was the most common, suggesting founder effect in Korea. POR deficiency is rare and can be misdiagnosed as 21-hydroxylase or 17α-hydroxylase/17,20-lyase deficiency. Therefore, molecular analysis is critical for confirmatory diagnosis.

An Alport syndrome boy with Van Wyk-Grumbach syndrome induced by prolonged untreated congenital hypothyroidism.

Alport syndrome (AS) is a rare genetic disorder that causes progressive nephritis and is more common among males. Studies have reported an association between thyroid antibodies and hypothyroidism in patients with AS, but the relevance of this relationship is under debate. Prolonged untreated hypothyroidism induces short stature, abnormal pubertal development, and various other symptoms. However, children with long-standing hypothyroidism rarely present with signs of precocious puberty, or Van Wyk-Grumbach syndrome (VWGS). We report the case of a boy, 8 years and 4 months old, who had VWGS caused by prolonged untreated congenital hypothyroidism and AS. The boy had repeated gross hematuria and proteinuria and was diagnosed with AS by renal biopsy and genetic testing. He had normal renal function but severe growth retardation and hypothyroidism. Obesity, bone age delay, hyperlipidemia, and abnormal increased testicle size were also present due to prolonged untreated hypothyroidism. His thyroid antibody titer elevation was unclear, although ultrasonography and thyroid scanning showed a decrease in thyroid volume. We diagnosed the patient with congenital hypothyroidism caused by thyroid dysgenesis. VWGS was diagnosed due to hypothyroidism, delayed bone age, and pseudoprecocious puberty. To the best of our knowledge, this is the first report of a prepubertal Korean boy with prolonged untreated congenital hypothyroidism complicated by VWGS in AS.

Combined surgical and medical treatment in an adolescent with severe gynecomastia due to excessive estradiol secretion: a case report.

BACKGROUND: Gynecomastia develops due to the reversed estradiol-to-Testosterone ratio in adolescence, and symptoms typically improve within 2 years. The causes vary widely, including estrogen excess and tumors, and surgical treatment is usually given in late adolescence because postoperative symptoms may recur in adolescents. This study reports a case of a pediatric patient with severe gynecomastia due to excessive estradiol secretion who showed a positive outcome after receiving surgical treatment combined with aromatase inhibitor administration. CASE PRESENTATION: A 9-year old boy visited to the Department of Pediatric Endocrinology for breast budding. At that time, the patient showed breasts at Tanner stage II and no abnormality on hormone tests. During a follow-up, both gynecomastia had progressed to Tanner stage III-IV at age 13. Tamoxifen 10 mg bid was administered; however, the condition rapidly progressed to Tanner stage V at 13.5 years. The evaluation of pathologic gynecomastia showed an increase of estradiol to 296 pg/mL with normal range 10 ~ 36 pg/mL and microlithiasis in both testes. As the condition worsened, total mastectomy was performed at the age of 13.5 years. Based on the assessment that elevated aromatase activity had induced breast budding, we changed the medication to anastrozole (Arimidex) 1 mg once a day, after which the estradiol level improved to 38.5 pg/mL and was maintained well in the two-year postoperative follow-up. CONCLUSIONS: This case report shows a combined plastic surgery and appropriate medical management bring a positive outcome in severe gynecomastia patient.

Delayed Bone Age Might Accelerate the Response to Human Growth Hormone Treatment in Small for Gestational Age Children with Short Stature.

PURPOSE: Growth hormone (GH) treatment is recommended to improve growth and psychosocial problems in short stature children born small for gestational age (SGA). Although GH therapy in these patients has been extensively studied, the impact of therapy according to delays in bone age (BA) is not known well. OBJECTIVE: To investigate the effects of GH therapy in SGA patients with short stature according to BA delay. METHODS: We retrospectively analyzed changes in height SD score (SDS) and BA/chronological age (CA) after 6 and 12 months of GH therapy in patients grouped according to BA delay. We studied 27 SGA children with short stature in the pediatric endocrinology clinic of Kyungpook National University Children's Hospital. RESULTS: Of the 27 patients, 9 had <2 years of BA delay, while 18 had >2 years of delay. There were no significant differences between the two groups in terms of gestational age and weight at birth, height SDS, IGF-1 SDS, and growth hormone dosage at the beginning of therapy. However, height SDS increased significantly in the group with >2 years of BA delay after 6 months of GH therapy (-2.50 ± 0.61 vs -1.87 ± 0.82; p=0.037) and 12 months (-2.27 ± 0.70 vs -1.63 ± 0.65; p=0.002). When height SDS was compared between with and without GHD, there were no significant differences. CONCLUSIONS: Delayed BA (>2 years) may impact the response to GH treatment in SGA children with short stature.

De novo a novel variant of CaSR gene in a neonate with congenital hypoparathyroidism.

Autosomal-dominant hypocalcemia with hypercalciuria (ADHH) is a genetic disease characterized by hypoparathyroidism with hypercalciuria. Most patients with ADHH have calcium-sensing receptor (CaSR) gene mutations. The CaSR gene controls parathyroid secretions, and mutations in this gene can be detected via changes in serum calcium level. The activating mutation of the CaSR gene results in familial or sporadic ADHH. Most activating mutations of the CaSR gene are reportedly de novo missense mutations. This is the first case report of a novel activating variant of the CaSR gene in a neonate with congenital hypoparathyroidism with hypomagnesemia and hypercalciuria. We also report the 3-month follow-up management of the patient.

A de novo KMT2D mutation in a girl with Kabuki syndrome associated with endocrine symptoms: a case report.

BACKGROUND: Kabuki syndrome is characterized by distinctive facial features and varying degrees of growth retardation. It leads to malformations in skeletal, urogenital and cardiac structures; moreover, endocrine conditions such as premature thelarche, precocious puberty, growth hormone deficiency, diabetes insipidus, thyroid dysfunction and obesity have been reported. Kabuki syndrome is caused by a heterozygous mutation in the KMT2D or KDM6A genes. CASE PRESENTATION: An 11-year-old girl with the typical facial features of Kabuki syndrome visited our hospital due to her short stature. She was found to have the de novo heterozygous mutation of c.8200C > T, p(Arg2734*) in exon 32 of the KMT2D gene and was diagnosed with Kabuki syndrome. The patient also exhibited endocrine abnormalities such as a constitutional delay of puberty, transiently congenial hypothyroidism, obesity and growth hormone deficiency. CONCLUSIONS: This is a case of a mutation in the KMT2D gene in a girl with Kabuki syndrome who presented with endocrine symptoms (constitutional delay of puberty, hypothyroidism, obesity and growth hormone deficiency).

Severe recurrent nocturnal hypoglycemia during chemotherapy with 6-mercaptopurine in a child with acute lymphoblastic leukemia.

Various endocrine dysfunctions occur during chemotherapy, including hypoglycemia. However, reports of hypoglycemia associated with 6-mercaptopurine (6-MP) are rare. Herein, we report an 8-year-old boy with severe symptomatic hypoglycemia likely due to 6-MP during chemotherapy. He had been diagnosed with acute lymphoblastic leukemia 3 years previously and was in the maintenance chemotherapy period. Treatment included oral dexamethasone, methotrexate, and 6-MP, of which only 6-MP was administered daily. Hypoglycemic symptoms appeared mainly at dawn, and his serum glucose dropped to a minimum of 37 mg/dL. Laboratory findings showed nothing specific other than increased serum cortisol, free fatty acids, ketone, alanine aminotransferase, and aspartate aminotransferase. Under the hypothesis of hypoglycemia due to chemotherapy drugs, we changed the time of 6-MP from evening to morning and recommended him to ingest carbohydrate-rich foods before bedtime. Hypoglycemia improved dramatically, and there was no further episode during the remaining maintenance chemotherapy period. To the best of our knowledge, this is the first report of this type of hypoglycemia occurring in an Asian child including Korean.

Severe vitamin D deficiency in preterm infants: maternal and neonatal clinical features.

PURPOSE: We investigated the vitamin D status of preterm infants to determine the incidence of vitamin D deficiency. METHODS: A total of 278 preterm infants delivered at Kyungpook National University Hospital between January 2013 and May 2015 were enrolled. The serum concentrations of calcium, phosphorous, alkaline phosphatase, and 25-hydroxyvitamin D (25-OHD) were measured at birth. We collected maternal and neonatal data such as maternal gestational diabetes, premature rupture of membranes, maternal preeclampsia, birth date, gestational age, and birth weight. RESULTS: Mean gestational age was 33(+5)±2(+2) weeks of gestation and mean 25-OHD concentrations were 10.7±6.4 ng/mL. The incidence of vitamin D deficiency was 91.7%, and 51.1% of preterm infants were classified as having severe vitamin D deficiency (25-OHD<10 ng/mL). The serum 25-OHD concentrations did not correlate with gestational age. There were no significant differences in serum 25-OHD concentrations or incidence of severe vitamin D deficiency among early, moderate, and late preterm infants. The risk of severe vitamin D deficiency in twin preterm infants was significantly higher than that in singletons (odds ratio, 1.993; 95% confidence interval [CI], 1.137-3.494, P=0.016). In the fall, the incidence of severe vitamin D deficiency decreased 0.46 times compared to that in winter (95% CI, 0.227-0.901; P=0.024). CONCLUSION: Most of preterm infants (98.9%) had vitamin D insufficiency and half of them were severely vitamin D deficient. Younger gestational age did not increase the risk of vitamin D deficiency, but gestational number was associated with severe vitamin D deficiency.

An explosion of a CNG fuel vessel in an urban bus.

An investigation is presented of the explosion of a CNG (compressed natural gas) fuel vessel, called a liner, in an urban bus. The explosion happened at a gas station 10 min after filling was completed. There were no traces of soot and flames at the failed liner, which would be indicative of explosion by ignition of the gas. The filling process of the station was automatically monitored and recorded in a computer. There was no unusual record of the filling system that indicated excess pressure at the time of the accident. There were cracks on the liner that were initiated at the outer surface of the cylindrical shell located at a point 4 cm above the lower dome where cracks did not originate easily as a result of overload. Chemical analysis was performed on a specimen that was cut from the liner, and there was no peculiarity in the mix. Mechanical analysis was performed on the specimens and showed that the hardness was not in the specified range because of inadequate heat treatment of the metal. The hardness of the liner was strictly controlled in the manufacturing process. All the liners that were manufactured at the same period with the failed liner were recalled for examination.