Novel Mutation of SLC26A3 Gene Observed in Congenital Chloride Diarrhea

Congenital chloride diarrhea (CLD) is a rare autosomal recessive disease caused by mutations in the solute carrier family 26 member 3 (SLC26A3) gene on chromosome 7q31. Affected neonates are vulnerable to dehydration, electrolyte imbalance in the form of hyponatremia, metabolic alkalosis, failure to thrive, or even death if left untreated. Genetic testing for mutations should be considered if the clinical diagnosis remains uncertain because early diagnosis and appropriate management are critical to the disease course in CLD. Several mutations have been reported in Korean patients with CLD, with the most common being the c.2063-1G>T mutation. Here, we report the case of a neonate with prenatally suspected CLD with confirmed novel mutations in the SLC26A3 gene (c.2147C>G; p.Ala716Gly).

Developmental Delay and Rehabilitation in an Infant with Partial Trisomy 1q32.1 to 1q44: A Case Report

Partial trisomy 1q is a rare chromosomal disorder characterized by ventriculomegaly with craniofacial, renal, cardiac, and finger and toe anomalies. Most reported cases of partial trisomy1q have involved stillborn or premature deaths due to cardiac or liver failure. This case report describes an 18-month-old patient with partial duplication of the 1q32-44 segments and consequent developmental delays who exhibited improvement in developmental status with rehabilitation. Prenatal ultrasonography and magnetic resonance imaging of the mother revealed ventriculomegaly and atrophic changes in the left cerebral hemisphere of the fetus. The infant was born with micrognathia, microphthalmia, macrocephaly, low-set ears, polydactyly, and long feet at 37+5 weeks of gestation. A chromosomal study revealed an abnormal male karyotype of 46,XY,rec(1)dup(1)(q32.1q44)inv(1)(p36.3q32.1)pat. In this rare case of a patient with partial trisomy, we observed improvement in developmental delays following treatment using appropriate rehabilitation techniques. Further research is required to help validate the findings of this case study and establish a standardized rehabilitation technique that can be subsequently applied to such cases.

Possibility of Combined Meningitis in Under 90-Day-Old Infants With Urinary Tract Infection

Purpose@#Urinary tract infections (UTIs) are the most common serious bacterial infections in young infants. Lumbar puncture (LP) has been used to diagnose coexisting meningitis in infants under 90 days of age with suspected UTI in many hospitals. However, the incidence of bacterial meningitis associated with UTIs is low. We aimed to describe the prevalence of concomitant bacterial meningitis in young infants with UTIs. @*Methods@#The medical records of infants with the first episode of UTI admitted to the ChungAng University Hospital from January 2010 to December 2019 were retrospectively reviewed. Infants aged < 90 days who underwent LP with initial evaluation were included. Demographic and clinical features, laboratory findings, and imaging findings were collected and analyzed. @*Results@#Eighty-six infants with UTIs were enrolled in the study. The median age was 61.5 days (interquartile range, 42.3–73.8 days) and boys (90.7%) were predominant. Escherichia coli was the most common pathogen (n=80, 93.0%) and followed by Klebsiella species (n=5, 5.8%). Fifteen (18.1%) specimens produced extended spectrum β-lactamase (ESBL). Five (5.8%) infants had positive blood culture results. Seven (8.1%) infants showed pleocytosis in the cerebrospinal fluid, but none had coexisting bacterial meningitis. Twenty-four (30.8%) infants showed renal dilatation or hydronephrosis on ultrasonography. Dimercaptosuccinic acid (DMSA) scans revealed cortical defects in 17 (21.3%) infants while voiding cystourethrography revealed vesicoureteral reflux in 6 (46.2%) infants. @*Conclusion@#Co-existing bacterial meningitis was not observed in young infants with UTIs. LP could not be routinely performed considering the clinical condition of <90 days old UTI patients.

Changes in the Occurrence of Gastrointestinal Infections after COVID-19 in Korea

Background@#After the global epidemic of coronavirus disease 2019 (COVID-19), lifestyle changes to curb the spread of COVID-19 (e.g., wearing a mask, hand washing, and social distancing) have also affected the outbreak of other infectious diseases. However, few studies have been conducted on whether the incidence of gastrointestinal infections has changed over the past year with COVID-19. In this study, we examined how the incidence of gastrointestinal infections has changed since COVID-19 outbreak through open data. @*Methods@#We summarized the data on the several viruses and bacteria that cause gastrointestinal infections from the open data of the Korea Disease Control and Prevention Agency for 3 years from March 2018 to February 2021 (from Spring 2018 to Winter 2020). Moreover, we confirmed three most common legal gastrointestinal infectious pathogens from March 2016. @*Results@#From March 2020, when the COVID-19 epidemic was in full swing and social distancing and personal hygiene management were heavily emphasized, the incidence of infection from each virus was drastically decreased. The reduction rates compared to the averages of the last 2 years were as follows: total viruses 31.9%, norovirus 40.2%, group A rotavirus 31.8%, enteric adenovirus 13.4%, astrovirus 7.0%, and sapovirus 12.2%. Among bacterial pathogens, the infection rates of Campylobacter and Clostridium perfringens did not decrease but rather increased in some periods when compared to the average of the last two years. The incidence of nontyphoidal Salmonella, Staphylococcus aureus, or enteropathogenic Escherichia coli somewhat decreased but not significantly compared to the previous two years. @*Conclusion@#The incidence of infection from gastrointestinal viruses, which are mainly caused by the fecal-to-oral route and require direct contact among people, was significantly reduced, whereas the incidence of bacterial pathogens, which have food-mediated transmission as the main cause of infection, did not decrease significantly.

Changes in the Occurrence of Gastrointestinal Infections after COVID-19 in Korea

Background@#After the global epidemic of coronavirus disease 2019 (COVID-19), lifestyle changes to curb the spread of COVID-19 (e.g., wearing a mask, hand washing, and social distancing) have also affected the outbreak of other infectious diseases. However, few studies have been conducted on whether the incidence of gastrointestinal infections has changed over the past year with COVID-19. In this study, we examined how the incidence of gastrointestinal infections has changed since COVID-19 outbreak through open data. @*Methods@#We summarized the data on the several viruses and bacteria that cause gastrointestinal infections from the open data of the Korea Disease Control and Prevention Agency for 3 years from March 2018 to February 2021 (from Spring 2018 to Winter 2020). Moreover, we confirmed three most common legal gastrointestinal infectious pathogens from March 2016. @*Results@#From March 2020, when the COVID-19 epidemic was in full swing and social distancing and personal hygiene management were heavily emphasized, the incidence of infection from each virus was drastically decreased. The reduction rates compared to the averages of the last 2 years were as follows: total viruses 31.9%, norovirus 40.2%, group A rotavirus 31.8%, enteric adenovirus 13.4%, astrovirus 7.0%, and sapovirus 12.2%. Among bacterial pathogens, the infection rates of Campylobacter and Clostridium perfringens did not decrease but rather increased in some periods when compared to the average of the last two years. The incidence of nontyphoidal Salmonella, Staphylococcus aureus, or enteropathogenic Escherichia coli somewhat decreased but not significantly compared to the previous two years. @*Conclusion@#The incidence of infection from gastrointestinal viruses, which are mainly caused by the fecal-to-oral route and require direct contact among people, was significantly reduced, whereas the incidence of bacterial pathogens, which have food-mediated transmission as the main cause of infection, did not decrease significantly.

Effects of Sedation Performed by an Anesthesiologist on Pediatric Endoscopy: a Single-Center Retrospective Study in Korea

Background@#Endoscopy is used for diagnosing and treating various digestive diseases in children as well as in adults. However, in pediatric patients, it is recommended that sufficient sedation should be ensured before conducting endoscopy, since insufficient sedation may cause serious complications. However, in Korea, no studies have yet described the types of sedation drugs, effects of sedation, and efficiency of endoscopy with respect to the sedation instructor. Thus, we investigated the effectiveness of sedative procedures performed by anesthesiologists. @*Methods@#We retrospectively reviewed the medical records of patients aged < 18 years who underwent endoscopy during March 2014–July 2019. Data of sedation instructors, sedation drugs and their doses, complications, and the recovery after sedation were evaluated. @*Results@#Of 257 patients, 217 underwent esophagogastroduodenoscopy (EGD) and 40 underwent colonoscopies. Before EGD, 29 patients (13.4%) underwent sedation by the pediatric endoscopist and 188 (86.6%) were sedated by the anesthesiologist. The anesthesiologist performed the sedation for all 40 patients who underwent colonoscopy. Endoscopic examinations performed by the anesthesiologist were relatively more time-consuming (401.0 ± 135.1 seconds vs. 274.9 ± 106.1 seconds, P < 0.001). We observed that in patients who underwent EGD, there was a difference in the dose of midazolam administered (P = 0.000). When comparing EGD and colonoscopy in patients undergoing sedation by the anesthesiologist, there were no significant differences in the doses of midazolam and ketamine, but the dose of propofol increased for colonoscopy (2.50 ± 0.95 mg/kg vs. 4.71 ± 1.66 mg/kg, P = 0.000). The cognitive recovery time according to drug dose was associated with propofol only in EGD with a shorter endoscopy time. The longer cognitive recovery time in colonoscopy and the discharge time of EGD and colonoscopies were not associated with propofol use. @*Conclusion@#When sedation is performed by an anesthesiologist, various drugs are used with sufficient doses and complications are reduced, but the discharge time does not change. For performing pediatric endoscopy in Korea, anesthesiologists should be considered for inducing anesthesia.

The Need for Early Screening for Iron Deficiency Anemia in 9- to 12-Month-Old Infants

PURPOSE@#Growth and development of infants can be periodically assessed through health screening, but iron deficiency anemia, which is common in infants, is difficult to detect by conducting only infant health screening. This study evaluated the prevalence of iron deficiency anemia in infants who visited Chung-Ang university hospital between 9 and 12 months of age. The study also determined the difference of anemia between term and preterm infants.@*METHODS@#The subjects of this study were infants aged 9 to 12 months who visited outpatient clinics of Chung-Ang University Hospital from January 2006 to August 2018 for the purpose of infant health screening and immunizations. We divided the subjects as the term group and the preterm group, and their medical records were retrospectively analyzed.@*RESULTS@#One hundred and fifty-two infants were included in the study. There were 51 in the preterm infant group and 101 in the term infant group. Thirteen infants were diagnosed with iron deficiency anemia, and 12 infants of these infants were in the term group and one infant was in the preterm group, which was statistically significant (P<0.001). There are significant differences in the hemoglobin (12.0±1.1 g/dL, 12.6±1.2 g/dL), hematocrit (35.8%±2.7%, 36.7%±3.2%), serum iron (60.8±25.4 µg/dL, 73.5±40.9 µg/dL), and unsaturated iron binding capacity (279.1±67.7 µg/dL, 252.0±47.5 µg/dL) between the term infant group and the preterm infant group, respectively (P<0.05).@*CONCLUSION@#Iron deficiency anemia was significantly more often diagnosed in term infants than that in preterm infants. Preterm infants may have a lower prevalence of iron deficiency anemia than do term infants because the preterm infants are taking iron supplements prophylactically. Therefore, iron deficiency anemia should be prevented in term infants, and it is important to confirm the presence of iron deficiency anemia by conducting blood tests during the first 9 to 12 months of life.

Posterior Nutcracker Syndrome with Microscopic Hematuria / 대한내과학회지

Nutcracker syndrome (NCS) refers to left renal vein compression with impaired blood outflow. The etiology of NCS has been attributed to various anatomic anomalies. Posterior NCS is caused by compression of the retroaortic left renal vein between the aorta and spine. The classic symptoms of NCS include left flank pain with gross or microscopic hematuria. The frequency and severity of the syndrome vary from asymptomatic microhematuria to severe pelvic congestion. For this reason, diagnosis of NCS is difficult and often delayed. Here, we report a case of posterior NCS that was incidentally discovered.

Macronutrient Analysis of Human Milk according to Storage and Processing in Korean Mother / 대한소아소화기영양학회지

PURPOSE: As the importance of breastfeeding has been reinforced, human milk is often stored for practical reasons. Therefore, we evaluated optimal storage and processing methods for human milk from a nutritional standpoint. METHODS: Human milk samples were collected between June 2017 and February 2018. Also, data about maternal information were collected. Human milk was analyzed for macronutrients and caloric content. The samples were subdivided into groups for nutrient analysis. The control group (fresh milk) was not stored or processed. The other groups (9 groups) consisted of samples analyzed based on different storage temperatures (room temperature, refrigerated, frozen), defrosting methods (bottle warmer, room temperature thawing, microwave oven), and storage period (1 week, 1 month, 2 months) and compared with the control group. RESULTS: There was no statistically significant difference in the nutrient content of human milk among the collected samples. A significant change in the content of macronutrients in milk samples was observed under storage condition at different temperatures for 1 week with subsequent thawing with bottle warmer compared to fresh milk. Under storage at −20°C for 1 week with subsequent thawing with different defrosting methods, a significant change in the content of macronutrients in milk samples was observed compared to fresh milk. After storage at −20°C for different periods and thawing with a bottle warmer, a significant change in macronutrient content in milk samples was observed compared to fresh milk regardless of the storage period. CONCLUSION: Unlike previous guidelines, changes in macronutrient content in milk samples were observed regardless of the method of storing and thawing. Apparently, it is proposed that mothers should feed fresh human milk to their babies without storing.

Influence of proton pump inhibitor therapy on intestinal inflammation assessed by fecal calprotectin in pediatric patients / 소아과

BACKGROUND: An increase in the numbers of patients with gastrointestinal symptoms has recently been observed. PURPOSE: To investigate the effects of proton pump inhibitor (PPI) therapy on intestinal inflammation in children and adolescents as confirmed by clinical manifestations and objectively assessed by fecal calprotectin (FC) level measurement. METHODS: Consecutive children (aged 3–18 years) who presented with gastrointestinal symptoms and were treated with or without PPI for at least 1 month were enrolled. Patients were divided into PPI and non-PPI groups. The PPI group was further subdivided by treatment duration and type of PPI used. Stool samples were collected for FC evaluation at baseline and after treatment and clinical data and FC levels were compared between the groups. RESULTS: Fifty-one patients (15 boys, 36 girls) were enrolled in the study. The PPI group included 37 patients, while the non-PPI group included 14 patients. Clinical symptoms were not significantly different. FC levels and laboratory results, including C-reactive protein levels, white blood cell count, and absolute neutrophil count, were not statistically different before versus after PPI treatment. After treatment, FC levels decreased to 8.1 mg/kg (-575.4 to 340.3 mg/kg) in the PPI group and increased to 5.6 mg/kg (-460.0 to 186.9 mg/kg) in the non-PPI group compared to those before treatment (P=0.841). The number of patients with increased FC levels was not significantly different between the 2 groups (48.6% vs. 64.3%, P=0.363), similar to that observed in patients with an FC level > 50 mg/kg (24.3% and 7.1%, P=0.250). PPI therapy type and duration did not affect the FC levels (P=0.811 and P=0.502, respectively). CONCLUSION: Although we aimed to confirm the evidence of intestinal inflammation due to PPI use in children and adolescents through clinical symptoms and FC measurement, no significant changes were observed.

Posterior Nutcracker Syndrome with Microscopic Hematuria / 대한내과학회지

Nutcracker syndrome (NCS) refers to left renal vein compression with impaired blood outflow. The etiology of NCS has been attributed to various anatomic anomalies. Posterior NCS is caused by compression of the retroaortic left renal vein between the aorta and spine. The classic symptoms of NCS include left flank pain with gross or microscopic hematuria. The frequency and severity of the syndrome vary from asymptomatic microhematuria to severe pelvic congestion. For this reason, diagnosis of NCS is difficult and often delayed. Here, we report a case of posterior NCS that was incidentally discovered.

Predictive Factors for Severe Thrombocytopenia and Classification of Causes of Thrombocytopenia in Premature Infants

PURPOSE: This study investigated predictive factors for severe neonatal thrombocytopenia, which greatly increases the need for intensive care and is associated with a high mortality rate in premature infants. Factors adopted for prompt identification of at-risk newborns include blood test results and birth history. This study analyzed the relationship between the presence of severe neonatal thrombocytopenia and the mortality rate. The causes of thrombocytopenia in premature infants were also examined. METHODS: This retrospective study evaluated 625 premature infants admitted to the neonatal intensive care unit (NICU) at Chung-Ang University Medical Center. The neonates were classified into 3 groups according to the severity of thrombocytopenia: mild (100×10⁹/L≤platelet < 150×10⁹/L), moderate (50×10⁹/L≤platelet < 100×10⁹/L), or severe (platelet < 50×10⁹/L). Analysis of blood samples obtained at the onset of thrombocytopenia included platelet count, white blood cell (WBC) count, hemoglobin level, hematocrit level, absolute neutrophil count, and high-sensitivity C-reactive protein level. RESULTS: Of the 625 premature infants admitted to our NICU, 214 were detected with thrombocytopenia. The mortality rate in thrombocytopenic neonates was 18.2% (39/214), whereas a mortality rate of only 1.0% was observed in non-thrombocytopenic neonates. The major causes of thrombocytopenia were perinatal insufficiency and sepsis in premature infants. Severe thrombocytopenia was noted more frequently in premature infants with higher WBC counts and in those with a younger gestational age. CONCLUSION: Platelet count, WBC count, and gestational age are reliable predictors for severe neonatal thrombocytopenia. The major causes of thrombocytopenia were perinatal insufficiency and sepsis in premature infants.

Iron Deficiency Anemia: The Possible Risk Factor of Complex Febrile Seizure and Recurrence of Febrile Seizure / 대한소아신경학회지

PURPOSE: A relationship between Febrile seizure (FS) and iron deficiency anemia (IDA) has been found in several studies. However, few studies have focused on the role of IDA in complex febrile seizures (CFS) and simple febrile seizures (SFS) and there is no report on whether IDA is a risk factor for recurrence. The aim of this study was to investigate the role of IDA in SFS and CFS and to examine the effect of IDA on recurrence. METHODS: Patients (n=166) who had been diagnosed with FS were enrolled in our study. Subjects were divided into the following groups for analysis: the SFS and CFS groups, recurrence and non-recurrence groups. The onset age was compared in each group of patients and laboratory test results based on IDA were compared. RESULTS: Between the SFS and the CFS groups, there was no significant difference in laboratory test results based on IDA. There was a significant difference in onset age between the two groups and the onset age tended to be lower in the CFS group (24.00 vs. 16.49 months) (P=0.004). Comparing recurrence and non-recurrence groups, the mean corpuscular volume was significantly different (P=0.043) with the recurrence group having a lower mean corpuscular volume level (78.92 vs. 77.48). The onset age in the recurrence group was lower (26.02 vs. 19.68 months). CONCLUSION: This study suggests that onset age could be a risk factor for CFS, and IDA may not contribute to elevating the risk of CFS. However, IDA may play an important role in the recurrence of FS.

Neonatal Patent Ductus Arteriosus Ligation Operations Performed by Adult Cardiac Surgeons

BACKGROUND: Patent ductus arteriosus (PDA) ligation is usually performed by congenital cardiac surgeons. However, due to the uneven distribution of congenital cardiac surgeons in South Korea, many institutions depend solely on adult cardiac surgeons for congenital cardiac diseases. We report the outcomes of PDA ligations performed by adult cardiac surgeons at our institution. METHODS: The electronic medical records of 852 neonates at Chung-Ang University Hospital, Seoul, South Korea from November 2010 to May 2014 were reviewed to identify patients with PDA. RESULTS: Of the 111 neonates with a diagnosis of PDA, 26 (23%) underwent PDA ligation. PDAs were ligated within 28 days of birth (mean, 14.5±7.8 days), and the mean gestational age of these patients was 30.3±4.6 weeks (range, 26 to 40 weeks) with a mean birth weight of 1,292.5±703.5 g (range, 480 to 3,020 g). No residual shunts through the PDA were found on postoperative echocardiography. There was 1 case of 30-day mortality (3.8%) due to pneumonia, and 6 cases of in-hospital mortality (23.1%) after 30 days, which is comparable to results from other centers with congenital cardiac surgery programs. CONCLUSION: Although our outcomes may not be generalizable to all hospital settings without a congenital cardiac surgery program, in select centers, PDA ligations can be performed safely by adult cardiac surgeons if no congenital cardiac surgery program is available.

Measurement and Estimation of Renal Size by Computed Tomography in Korean Children

Adequate organ growth is an important aspect of growth evaluation in children. Renal size is an important indicator of adequate renal growth; computed tomography (CT) can closely estimate actual kidney size. However, insufficient data are available on normal renal size as measured by CT. This study aimed to evaluate the relationships of anthropometric indices with renal length and volume measured by CT in Korean pediatric patients. Renal length and volume were measured using CT images in 272 pediatric patients (age < 18 years) without renal disease. Data for anthropometric indices—including height, weight, and body surface area (BSA)—were obtained using medical records. Using the equation for an ellipsoid, renal volume was calculated in cubic centimeters. Height showed greatest correlation with renal length on stepwise multiple linear regression analysis; BSA showed the strongest significant correlation with renal volume. The mean renal size for each age group and height group was determined; it showed a tendency to increase with age and height. This is the first Korean study to report the relationship between body indices and renal size measured by CT. These results can serve as normative standards for assessing adequate renal growth.

A Rare Case of Cerebral Sinovenous Thrombosis Associated with MTHFR A1298C and C677T Mutations

Neonatal cerebral sinovenous thrombosis (CSVT) is a rare disease with severe neurological sequelae. Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in the folate cycle, and mutations in MTHFR are associated with vascular diseases. Here, we report the case of a newborn with MTHFR mutation-associated CSVT. Analysis of MTHFR in the patient detected heterozygous C677T (677CT) and A1298C (1298AC) mutations. Analysis of MTHFR in the patient's mother did not detect a C677T (677CC) mutation but detected a homozygous A1298C (1298CC) mutation. Our results suggest that the presence of heterozygous MTHFR C677T and A1298C mutations affect thrombophilic activity in the neonate, resulting in the development of refractory seizure and CSVT. Moreover, presence of the homozygous MTHFR A1298C mutation in the patient's mother, who did not show any symptoms associated with thrombophilic activity, and conditions during gestation may have affected the patient's condition.

Meckel diverticulum in exomphalos minor

A congenital hernia into the base of the umbilical cord is known as an exomphalos and when the size of the defect is 5 cm or less and containing only bowel, it is called as exomphalos minor. We present a case of a newborn with an exomphalos minor within a Meckel diverticulum. He underwent surgical resection of the Meckel diverticulum and repair of the abdominal wall defect. To our knowledge, this is the first reported case of Meckel diverticulum in an exomphalos minor in Korea.

The Correlation between Maternal Adult Attachment Style and Postpartum Depression and Parenting Stress / 신경정신의학

OBJECTIVES: We aimed to determine whether the adult attachment styles of pregnant women could predict development of postpartum depression. METHODS: Korean version of Revised Adult Attachment Scale, State Trait Anxiety Inventory-State/Trait (STAI-S/T), and Center for Epidemiologic Studies-Depression Scale (CES-D) were administered at baseline. Edinburgh Postnatal Depression Scale (EPDS), Parenthood Stress Questionnaire (PSQ), STAI-S, and CES-D were assessed at week 2 and 6 postpartum. Participants were categorized into the secure-mom (SM ; n=48) or insecure-mom (IM ; n=9) group. RESULTS: While STAI-S scores in SM showed a continuous decrease during the entire observation period, STAI-S scores in IM decreased during the first two weeks but increased during the next four weeks. While SM showed decreased CES-D scores from week 2 to 6, IM showed increased CES-D scores from week 2 to 6. Although SM showed decreased EPDS scores from week 2 to 6, IM showed increased EPDS scores from week 2 to 6. In SM, the change in EDPS score from week 2 to week 6 showed positive correlation with PSQ-ability and PSQ-social subscale scores. CONCLUSION: Assessing the maternal adult attachment style before giving birth appears to be helpful for screening the high-risk group who are vulnerable to development of postpartum depression.

Double Intussusceptions with Necrotizing Enterocolitis Diagnosed in a Premature Infant

Intussusception in neonates, especially in preterm infants, is rare. Common symptoms of intussusception, which include distended abdomen and gastric residuals, lead to misdiagnosis as necrotizing enterocolitis (NEC). Delayed diagnosis of neonatal intussusception delays treatment as well, which can lead to life-threatening complications. The predominant location of intussusception in preterm neonates is the small bowel; therefore, ultrasonography is not indicated. We report the case of an 834g male baby born at 25 weeks 6 days of gestation, who was diagnosed with double intussusceptions with NEC.

Neuroprotective effects of mild hypoxia in organotypic hippocampal slice cultures / 소아과

PURPOSE: The aim of this study was to investigate the potential effects of mild hypoxia in the mature and immature brain. METHODS: We prepared organotypic slice cultures of the hippocampus and used hippocampal tissue cultures at 7 and 14 days in vitro (DIV) to represent the immature and mature brain, respectively. Tissue cultures were exposed to 10% oxygen for 60 minutes. Twenty-four hours after this hypoxic insult, propidium iodide fluorescence images were obtained, and the damaged areas in the cornu ammonis 1 (CA1), CA3, and dentate gyrus (DG) were measured using image analysis. RESULTS: In the 7-DIV group compared to control tissue, hypoxia-exposed tissue showed decreased damage in two regions (CA1: 5.59%+/-2.99% vs. 4.80%+/-1.37%, P=0.900; DG: 33.88%+/-12.53% vs. 15.98%+/-2.37%, P=0.166), but this decrease was not statistically significant. In the 14-DIV group, hypoxia-exposed tissue showed decreased damage compared to control tissues; this decrease was not significant in the CA3 (24.51%+/-6.05% vs. 18.31%+/-3.28%, P=0.373) or DG (15.72%+/-3.47% vs. 9.91%+/-2.11%, P=0.134), but was significant in the CA1 (50.91%+/-5.90% vs. 32.30%+/-3.34%, P=0.004). CONCLUSION: Although only CA1 tissues cultured for 14 DIV showed significantly less damage after exposure to hypoxia, the other tissues examined in this study showed a tendency towards less damage after hypoxic exposure. Therefore, mild hypoxia might play a protective role in the brain.