Jung Sook Yeom

Frequency of and risk factors for oxcarbazepine-induced severe and symptomatic hyponatremia

PURPOSE Hyponatremia is one of the most common adverse effects in patients treated with oxcarbazepine (OXC). Most patients with OXC-induced hyponatremia are asymptomatic, so the presence of severe or symptomatic hyponatremia, which requires electrolyte correction or discontinuation of OXC therapy, has more important clinically implications. However, data for OXC-induced severe and symptomatic hyponatremia are limited. METHODS We reviewed medical records of all patients with epilepsy who were treated with OXC at the Seoul National University Hospital. We analyzed serum sodium level results and attempted to identify correlations between various factors and the frequency of severe and symptomatic OXC-induced hyponatremia. RESULTS Data from a total 1009 patient were examined. The frequency of severe and symptomatic hyponatremia was 11.1% and 6.8%, respectively. Multivariate analysis revealed that age (P=0.014, OR 1.014), antiepileptic drug (AED) polytherapy (P=0.040, OR 1.540), and the concomitant use of diuretics (P<0.001, OR 5.597) were independent risk factors for OXC-induced severe hyponatremia. Age (P=0.001, OR 1.034) and the concomitant use of diuretics (P=0.035, OR 2.222) were independent risk factors for OXC-induced symptomatic hyponatremia. The frequency of OXC-induced symptomatic hyponatremia that was judged to be clinically significant was 2.8% among the total OXC-treated epilepsy patients. CONCLUSION Our study recommended that serum sodium be monitored regularly in patients taking OXC, especially in old age, AED polytherapy or concomitant use of diuretics, to assist in the early recognition of hyponatremia and to increase the awareness of symptoms that might be attributable to this.

Changing pattern of antibiotic resistance of Helicobacter pylori in children during 20 years in Jinju, South Korea

The antimicrobial resistance capability of Helicobacter pylori is one of the critical factors in the failure to treat this pathogen. The purpose of this study was to investigate the changing pattern of primary antibiotic resistance rates in children in the southern central part of South Korea from 1990 to 2009.

Distinctive pattern of white matter injury in neonates with rotavirus infection

Objective: To report a consecutive series of neonates with seizures or apnea and displaying white matter injuries with distinctive magnetic resonance diffusion-weighted imaging (DWI) pattern, and to discuss the high positive rate of rotavirus infection seen in these patients. Methods: In a retrospective review of neonates who were admitted to a tertiary referral center with seizures or apnea, we found a distinctive pattern of white matter injury (symmetrical restricted diffusion in the periventricular white matter and white matter tracts including the corpus callosum) in 18 patients. We describe the clinical and laboratory features of these 18 neonates. Additional PCR analyses for rotaviruses and parechoviruses were performed on banked frozen samples of CSF of 4 patients and blood of 15 patients. Results: All 18 patients were born at term and healthy until symptoms occurred 4–7 days after birth. No history of asphyxia was observed. Only 1 patient presented with fever, and no patient showed a rash. All patients except 1 (94.4%) were rotavirus-positive in stool samples. However, neither rotaviruses nor enteroviruses/parechoviruses were detected in the CSF and blood. Tissue loss was observed in 5 of 8 subjects on repeat MRI scans. Conclusions: Neonates with this distinctive DWI pattern had a high positive rate of rotavirus infection, without evidence of other pathogens, and were characterized as term newborns with neurologic symptoms arising approximately the fifth day after birth. Although the specificity of this pattern is unclear, rotavirus testing should be considered for neonates presenting with this DWI pattern.

Prevalence of human parechovirus and enterovirus in cerebrospinal fluid samples in children in Jinju, Korea.

Purpose Human parechovirus (HPeV) and enterovirus (EV) are causative agents of a sepsis-like illness in neonates and of infections of the central nervous system in young children. The objectives of this study were to assess the prevalence of HPeV3 and EV infection in young children with a sepsis-like illness or with meningitis in Jinju, Korea. Methods Cerebrospinal fluid (CSF) samples were collected from 267 patients (age range, 1 day to 5 years) and assessed for HPeV and EV by performing reverse transcription polymerase chain reaction assay. Amplification products of the VP3/VP1 region of HPeV and of the VP1 region of EV were sequenced to identify the virus type. Results HPeV and EV were detected in 3.4% and 7.5% of the total CSF samples assessed, respectively. The age distribution of EV-positive patients (median age, 1.4 months) had a significantly broader range than that of HPeV-positive patients (median age, 7.8 months). The peak seasons for HPeV and EV infection were spring and summer, respectively. The clinical symptoms for HPeV and EV infection were similar, and fever was the most common symptom. Pleocytosis was detected in 22.2% of HPeV-positive patients and 35.5% of EV-positive patients. The VP3/VP1 gene sequence of the nine Korean strains clustered most closely with the Japanese strain (AB759202). Conclusion The data indicate that HPeV infection is predominant in young infants (<6 months) and that meningitis without pleocytosis was caused by both HPeV and EV infection in children.

Role of Ca2+ homeostasis disruption in rotavirus-associated seizures.

Rotavirus infection disturbs cellular Ca2+ homeostasis by triggering an increase in Ca2+ permeation. A theoretical link between Ca2+ dysregulation and seizures in patients with rotavirus gastroenteritis has been suggested, but no prior studies have investigated this relationship. To test our hypothesis that patients with rotavirus-associated seizures have greater Ca2+ homeostasis disruption than those without seizures, we compared clinical and laboratory data—including corrected total serum Ca2+ levels—between the 2 groups. Age, gender, maximum body temperature, day of admission, levels of electrolytes except Ca2+, blood pH, and urine ketone levels were not related to seizure occurrence. Significantly lower Ca2+ levels were found among the seizure (+) group (9.22 ± 0.50 vs 9.66 ± 0.46 mg/dL, P = .01). Although Ca2+ levels were within normal ranges and did not directly cause the seizures, our results provide preliminary evidence for a relationship between Ca2+ homeostasis disruption and seizures in rotavirus patients.

Correlation between Positive Rate and Number of Biopsy Samples on Urease Test in Childhood Helicobacter pylori Infection

To identify the correlation between the number of gastric biopsy samples and the positive rate, we compared the results of urease test using one and three biopsy samples from each 255 children who underwent gastroduodenoscopy at Gyeongsang National University Hospital. The children were divided into three age groups: 0-4, 5-9, and 10-15 yr. The gastric endoscopic biopsies were subjected to the urease test. That is, one and three gastric antral biopsy samples were collected from the same child. The results of urease test were classified into three grades: Grade 0 (no change), 1 (6-24 hr), 2 (1-6 hr), and 3 (<1 hr). The positive rate of urease test was increased by the age with no respect to the number of gastric biopsy samples (one biopsy P = 0.001, three biopsy P < 0.001). The positive rate of the urease test was higher on three biopsy samples as compared with one biopsy sample (P < 0.001). The difference between one and three biopsy samples was higher in the children aged 0-9 yr. Our results indicate that the urease test might be a more accurate diagnostic modality when it is performed on three or more biopsy samples in children.

Influencing Factors to Results of the Urease Test: Age, Sampling Site, Histopathologic Findings, and Density of Helicobacter pylori.

Purpose We investigated the positivity rate and the time period to the positive color change of the urease test in children and adults and assessed the correlation of the urease test to histopathologic findings. Methods From 1995 to 2000, endoscopic biopsies of the antrum and body were collected from 811 children and 224 adults and subjected to urease tests and histopathology. Results The positivity rate of the urease test was 49.4% for 0-4 years, 48.4% for 5-9 years, 47.3% for 10-15 years, and 62.5% for 20-29 years in the antrum. The positivity rate was 85.1% in 0-4 years, 82.3% in 5-9 years, 74.7% in 10-15 years, and 74.1% in 20-29 years for the body. In the antrum, the highest positivity rate was <1 hour for the group aged 10-29 years and 6-24 hours in the group <10 years old (p<0.0001). In the body, the highest positivity rate was <1 hour in adults and 6-24 hours in children (p<0.0001). The proportions of the positive reactions within 1 hour were similar for the antrum and the body. In the cases of more severe chronic gastritis, active gastritis, and Helicobacter pylori infiltration, a positive urease test reaction occurred more quickly (p<0.0001). Conclusion There were significant differences in urease tests according to age and sampling site. The discrepancy between the antrum and the body was greater in younger children. These results might be related to the low density and patchy distribution of bacteria in children and in the body.

Kawasaki disease in infants

Kawasaki disease (KD) is an acute febrile illness that is the predominant cause of pediatric acquired heart disease in infants and young children. Because the diagnosis of KD depends on clinical manifestations, incomplete cases are difficult to diagnose, especially in infants younger than 1 year. Incomplete clinical manifestations in infants are related with the development of KD-associated coronary artery abnormalities. Because the diagnosis of infantile KD is difficult and complications are numerous, early suspicion and evaluation are necessary.

Association between Gastric pH and Helicobacter pylori Infection in Children.

Purpose To assess gastric pH and its relationship with urease-test positivity and histological findings in children with Helicobacter pylori infection. Methods Fasting gastric juices and endoscopic antral biopsy specimens were collected from 562 children and subjected to the urease test and histopathological examination. The subjects were divided into 3 age groups: 0-4, 5-9, and 10-15 years. The histopathological grade was assessed using the Updated Sydney System, while the gastric juice pH was determined using a pH meter. Results The median gastric juice pH did not differ significantly among the age groups (p=0.655). The proportion of individuals with gastric pH >4.0 was 1.3% in the 0-4 years group, 6.1% in the 5-9 years group, and 8.2% in 10-15 years (p=0.101). The proportions of moderate and severe chronic gastritis, active gastritis, and H. pylori infiltration increased with age (p<0.005). Urease-test positivity was higher in children with hypochlorhydria (77.8%) than in those with normal gastric pH (31.7%) (p<0.001). Chronic and active gastritis were more severe in the former than the latter (p<0.001), but the degree of H. pylori infiltration did not differ (20.9% vs. 38.9%; p=0.186). Conclusion Gastric pH while fasting is normal in most children regardless of age. Urease-test positivity may be related to hypochlorhydria in children, and hypochlorhydria is in turn related to H. pylori infection.

Prognostic Value of Initial Standard EEG and MRI in Patients with Herpes Simplex Encephalitis

Background and Purpose Herpes simplex encephalitis (HSE) is the most common type of sporadic encephalitis worldwide, and it remains fatal even when optimal antiviral therapy is applied. There is only a weak consensus on the clinical outcomes and prognostic factors in patients with HSE. This study examined whether the radiological and electrophysiological findings have a prognostic value in patients with HSE. Methods We retrospectively analyzed patients who were diagnosed with HSE by applying the polymerase chain reaction to cerebrospinal fluid and who received intravenous acyclovir at our hospital from 2000 to 2014. We evaluated the clinical outcomes at 6 months after onset and their correlations with initial and clinical findings, including the volume of lesions on MRI, the severity of EEG findings, and the presence of epileptic seizures at the initial presentation. Results Twenty-nine patients were enrolled (18 men and 11 women). Univariate analysis revealed that the presence of severe EEG abnormality and epileptic seizures at the initial presentation were significant correlated with a poor clinical outcome at 6 months (p=0.005 and p=0.009, respectively). In multivariate analysis, the presence of severe EEG abnormality was the only independent predictor of a poor outcome at 6 months (p=0.006). Conclusions In cases of HSE, the initial EEG severity and seizure presentation may be useful predictive factors for the outcome at 6 months after acyclovir treatment.