Clinical Practice Guidelines for Oropharyngeal Dysphagia / 대한연하장애학회지

Objective@#Dysphagia is a common clinical condition characterized by difficulty in swallowing. It is sub-classified into oropharyngeal dysphagia, which refers to problems in the mouth and pharynx, and esophageal dysphagia, which refers to problems in the esophageal body and esophagogastric junction. Dysphagia can have a significant negative impact one’s physical health and quality of life as its severity increases. Therefore, proper assessment and management of dysphagia are critical for improving swallowing function and preventing complications. Thus a guideline was developed to provide evidence-based recommendations for assessment and management in patients with dysphagia. @*Methods@#Nineteen key questions on dysphagia were developed. These questions dealt with various aspects of problems related to dysphagia, including assessment, management, and complications. A literature search for relevant articles was conducted using Pubmed, Embase, the Cochrane Library, and one domestic database of KoreaMed, until April 2021. The level of evidence and recommendation grade were established according to the Grading of Recommendation Assessment, Development and Evaluation methodology. @*Results@#Early screening and assessment of videofluoroscopic swallowing were recommended for assessing the presence of dysphagia. Therapeutic methods, such as tongue and pharyngeal muscle strengthening exercises and neuromuscular electrical stimulation with swallowing therapy, were effective in improving swallowing function and quality of life in patients with dysphagia. Nutritional intervention and an oral care program were also recommended. @*Conclusion@#This guideline presents recommendations for the assessment and management of patients with oropharyngeal dysphagia, including rehabilitative strategies.

Effect of Repetitive Transcranial Magnetic Stimulation on Patients With Dysarthria After Subacute Stroke

OBJECTIVE: To evaluate whether repetitive transcranial magnetic stimulation (rTMS) could improve dysarthria in stroke patients at the subacute stage. METHODS: This study was a prospective, randomized, double-blind controlled trial. Patients who had unilateral middle cerebral artery infarction were enrolled. In patients in the rTMS group, we found hot spots by searching for the evoked motor potential of the orbicularis oris on the non-affected side. We performed rTMS at a low frequency (1 Hz), 1,500 stimulations/day, 5 days a week for 2 weeks on the hotspots. We used the same protocol in the sham stimulation group patients as that in the rTMS group, except that the angle of the coil was perpendicular to the skull rather than tangential to it. The patients in both groups received speech therapy for 30 minutes, 5 days a week from a skilled speech therapist. The speech therapist measured the Urimal Test of Articulation and Phonology, alternative motion rates, sequential motion rates, and maximal phonation time before and after intervention sessions. RESULTS: Forty-two patients were enrolled in this study and 20 completed the study. Statistical analysis revealed significant improvements on the dysarthria scales in both groups. The sequential motion rate (SMR)-PTK showed significantly greater improvement in the rTMS group patients than in the sham stimulation group. CONCLUSION: Patients in the rTMS group showed greater improvement in articulation than did patients in the sham rTMS group. Therefore, rTMS can have a synergistic effect with speech therapy in treating dysarthria after stroke.

Comorbidity of Posttraumatic Stress Disorder and Its Effect on Treatment Outcomes in Patients with Schizophrenia : One-Year Prospective Follow-Up Study

OBJECTIVES: The aims of this study were to assess a) the prevalence of trauma and posttraumatic stress disorder(PTSD) in schizophrenic patients and b) the differences in symptomatology and outcome after 1year treatment between those with and without PTSD. METHODS: Twenty eight schizophrenia and schizoaffective disorder patients completed the Positive and Negative Syndrome Scale(PANSS), Life Stressor Checklist-Revised(LSCL-R), Clinician-Administered PTSD Scale (CAPS), Dissociative Experiences Scale(DES), Hamilton Psychiatry Rating Scale for Depression(HAM-D), and Rosenberg Self-Esteem Scale(RSE). RESULTS: Twenty six patients(92.9%) had at least one trauma in their life time. Eleven patients(39.3%) were diagnosed with PTSD. PTSD group had significantly higher scores on HAM-D and DES but lower scores on RSE. PTSD group also had significantly lower score in the baseline PANSS Negative score. Higher CAPS scores were significantly correlated with lower baseline PANSS Negative score and greater change after 1year of PANSS Negative score. CONCLUSION: These results showed that the prevalences of trauma and PTSD are high in schizophrenic patients and suggested that PTSD and trauma-related symptoms affected the symptomatology and treatment outcome. More research is warranted to better understand the effects of PTSD in schizophrenic patients.

A Case of Mycoplasma pneumoniae Pneumonia with a Fulminant Course in a Previously Healthy Boy / 소아알레르기및호흡기학회지

Mycoplasma pneumoniae is a common cause of community-acquired respiratory infection in children. Through uncertain pathologic mechanisms, which most probably involve immunologically cell-mediated tissue damage, it causes life-threatening disease on rare occasion. We herein report a case of M. pneumoniae pneumonia, with encephalopathy followed by multiple organ failure in a previously healthy boy. Despite of intensive therapies with intravenous antibiotics, corticosteroid, hemodiafiltration, and transfusion, his neurologic and pulmonary sequales have remained. In most cases M. pneumoniae pneumonia are usually self- limiting with benign outcome. Even in healthy individual, however, it can manifest itself with a fulminant course and multi organ failure.

Airway Compression or Airway Anomaly Causing Respiratory Symptoms in Infants and Children with Cardiovascular Diseases / 소아과

PURPOSE: Infants and children with cardiovascular diseases often present with respiratory symptoms. However, missed or delayed evaluation for potential airway problem may complicate overall prognosis. The aim of this study is to determine the clinical characteristics of these patients and explore the cause of airway problem. METHODS: We reviewed the medical records of 64 patients (M: F=33: 31, mean age: 6.3+/-7.5 months) whose airway problems were proven by computed tomography or bronchoscopy in perioperative periods at the Asan Medical Center from January 1997 to June 2004. Patients were divided into two groups based on the duration of ventilator care: 7 days (group 2: 41 cases, M: F=23: 18). RESULTS: The patients in group 2 significantly developed more post-operative respiratory symptoms than group 1 (P< 0.001) and had more airway problems including extrinsic obstruction, intrinsic anomaly, and combined problem than group 1 although not significantly different (P=0.082). Among underlying diseases, the most common diseases were vascular anomaly (26.2 percent) and aortic arch anomaly (26.2 percent) in group 1 and pulmonary atresia with ventricular septal defect (22.4 percent) in group 2. The most frequent respiratory symptoms were recurrent wheezing pre-operatively and failure of ventilator weaning post-operatively. The major types of airway anomaly were tracheomalacia and tracheal stenosis (in each case 18.2 percent). Nineteen patients with persistent airway problems underwent aortopexy or other vascular correction. Of the 19 patients, 13 (68.4 percent) were improved, but 2 failed in weaning ventilator and 4 died of non-airway problems. CONCLUSION: Early evaluation and treatment for potential airway problems may affect natural or surgical prognosis in patients with cardiovascular diseases presenting with respiratory symptoms.

A Case of Transfusion Transmitted Malaria Infection in Extremely Low Bith Weight Infant

The incidence of malaria in Korea is significantly on the rise since its reemergence in 1993 and no screening test that can prevent the infection has been available. Very low birth weight infants are especially susceptible to malaria infection due to transfusions from multiple donors. We report a case of transfusion transmitted Plasmodium vivax infection in a 120-day-old infant of a gestational age 24 weeks with birth weight of 700 gm who was successfully treated with hydroxychloroquine.

Stimulation of Bactericidal and Fungicidal Activity of Neonatal Monocytes by Immunoactivating Peptide

PURPOSE: To evaluate the function of Trp-Lys-Tyr-Met-Val-D-Met (WKYMVm) in human neonatal monocytes. METHODS: The peptide, Trp-Lys-Tyr-Met-Val-D-Met (WKYMVm), was synthesized, purified, and prepared in the Peptide Library Support Facility at Pohang University of Science and Technology. Female Sprague-Dawley rats (200+/-10 g) were preinfected with S. aureus and treated with WKYMVm through femoral vein. At various time points, blood samples were obtained by puncture of femoral artery and the serum was plated on the nutrient agar plate. The number of viable bacteria was determined by counting the number of bacterial colonies. In addition, using S. aureus and C. albicans, we evaluated the bactericidal and fungicidal activities of neonatal monocytes, which were separated from umbilical cord blood by Ficoll gradient. RESULTS: The numbers of bacteria in the blood of WKYMVm-treated rats were rapidly decreased with time, as compared with those of the untreated rats. The peptide treatment enhanced the bactericidal activity in vivo within 10 minutes. In neonatal monocytes, WKYMVm stimulated the intracellular killing of S. aureus in a dose dependent manner, showing the maximum effect at 100 nM. WKYMVm stimulated the phagocytic and fungicidal activities against C. albicans in a dose dependent manner, with the maximum effect at the 100 nM. CONCLUSION: These results suggest that WKYMVm may be an effective agent against the neonatal infections.

Perinatal Risk Factors for the Development of Bronchopulmonary Dysplasia in Premature Infants Less Than 32 Weeks' Gestation

OBJECTIVES: To determine the clinical characteristics and perinatal risk factors of infants with bronchopulmonary dysplasia (BPD) among premature infants less than 32 weeks' gestation and access the role of ventilatory indices and maternal factors that may predispose preterm infants to the development of chronic lung disease (CLD). METHODS: Clinical data was collected retrospectively from the 256 premature infants less than 32 weeks' gestation and their mothers during 3-year study period. RESULTS: Among 212 preterm infants less than 32 weeks' gestation who survived to 28 days of life, 58 (27.4%) had CLD. Predisposing neonatal factors for developing CLD included lower gestational age, lower birth weight, Apgar score at 1 and 5 minute, occlusion of PDA after day 4 of age, birth weight nadir and the duration reached to it, serum level of total white blood cell (WBC) at birth, and the level of IgM over 30 mg/dL within 7 days after birth. Maternal factors for developing CLD in their infants included maternal age, mode of delivery, use of antenatal corticosteroid, and the level of WBC count in amniotic fluid (>50/mm3). FiO2 at day 2, PIP at day 2-7 and 10, MAP at day 2, 3, 5 and 10, and oxygenation index at day 2, 3, 5-7, and 10 were significant risk factors in development of CLD. Furthermore, PIP per birth weight, MAP per birth weight, and modified oxygenation index far better predicted the development of CLD than PIP, MAP and oxygenation index per se at any ages of all infants included in the study. CONCLUSION: In addition to neonatal factors, maternal factors including age, mode of delivery, use of antenatal corticosteroid, and the level of WBC count in amniotic fluid (>30/mm3) can be used as risk factors in predicting the development of CLD in their infants. Variable ventilatory indices (PIP, MAP, oxygenation index) in relation to birth weight could better predict the development of CLD in infants less than 32 weeks' gestation.

Early Prediction of Hypoxic-Ischemic Brain Damage in Newbon Rats Using Proton Magnetic Resonance Spectroscopy and Neuroprotective Effect of EGb 761

PURPOSE: This study was designed to evaluated the relationship between the morphological changes of hypoxic-ischemic injured brain and the magnetic resonance spectroscopic (MRS) findings, and the efficacy of Egb 761, a free radical scavenger, as a neuroprotective agent for hypoxic-ischemic brain injury. METHODS: Seven-day old Sprague-Dawley rat pups were used. Right common carotid artery was ligated under halothene anesthesia. After a recovery period of 3 hours, they were divided into two groups : for group 1, EGb 761 100 mg/kg (treatment group) and for group 2, normal saline (control group) were given intraperitoneally. Both groups were exposed to 8% oxygen at 37degrees C for 90 minutes. Sixty-four rat pups (30 control, 34 treatment group) were examined with localized 1H MRS on days 1 and 7 after the hypoxic insult. One day 14, the degree of brain injury was scored by morphological changes. RESULTS: The 1H MRS obtained on day 1 after the hypoxic insult showed increased Lip/NAA and Lip/Cr ratios in the right cerebral hemisphere in comparison with those in the left hemisphere (P<0.01). The degree of morphological changes of the brain injury on day 14 correlated with both Lip/NAA and Lip/Cr ratios obtained on days! and 7 after the hypoxic insult [r=0.410, 0.457 on day 1, and r=0.749, 0.720 on day 7, respectively (P< 0.01)]. The therapeutic potential of EGb 761 for the hypoxic-ischemic brain seemed insignificant, as was evident from no differences between the control group and the EGb 761 treatment group in the Lip/NAA and Lip/Cr ratios as well as in morphological changes. CONCLUSION: Early changes of Lip/NAA and Lip/Cr ratios in the 1H MRS seems to be related to the degree of morphological changes in the rat brain of hypoxic-ischemic injury. Therefore, the increased lipid content of brain observed by 1H MRS can be used as a marker to predict the degree of the hypoxic-ischemic injury. The neuroprotectiveeffect of EGb 761 in hypoxic-ischemic brain injury is insignificant.

Total Parenteral Nutrition-associated Cholestasis in Very Low Birth Weight Infants

PURPOSE: Very low birth weigh infants (VLBWI), who often require a long-term parenteral nutrition, are at high risk for the development of parenteral nutrition-associated cholestasis. This study was conducted to determine the incidence of total parenteral nutrition (TPN)-associated cholestasis and its risk factors in the VLBI. We evaluated the clinical courses and outcomes. METHODS: The hospital records of 165 VLBWI who were admitted to the neonatal intensive care unit at Asan medical center from Jan. 1997 to Dec. 1999 and received TPN for more than 2 weeks were reviewed. Cholestasis was defined as a direct serum bilirubin level greater than 2.0 mg/dl during the period of TPN, and other causes of cholestasis were ruled out. RESULTS: Twenty-seven out of 165 VLBWI developed TPN-associated cholestasis with the incidence of 16.4%. Significant risk factors for the development of cholestasis included birth weight, small for gestational age, duration of enteral starvation, duration of parenteral nutrition, septic episodes, necrotizing enterocolitis, and the number of surgery in 30 days of age. Cholestasis occurred at the mean age of 48.8+/-20.7 days and resolved in 53.7+/-8.8 days after onset of cholestasis. The mortality rate of infants with cholestasis was significantly higher than that of infants without cholestasis. Two infants appeared to die of a progressive hepatic dysfunction associated with TPN. CONCLUSION: TPN-associated cholestasis is relatively common in VLBWI, and may progress to the hepatic failure and death. The strategies such as early enteral feeding or the reduction of septic episodes would need to be seriously adopted in order to prevent the morbidity and mortality from TPN-associated cholestasis.

Total Parenteral Nutrition-associated Cholestasis in Very Low Birth Weight Infants

PURPOSE: Very low birth weigh infants (VLBWI), who often require a long-term parenteral nutrition, are at high risk for the development of parenteral nutrition-associated cholestasis. This study was conducted to determine the incidence of total parenteral nutrition (TPN)-associated cholestasis and its risk factors in the VLBI. We evaluated the clinical courses and outcomes. METHODS: The hospital records of 165 VLBWI who were admitted to the neonatal intensive care unit at Asan medical center from Jan. 1997 to Dec. 1999 and received TPN for more than 2 weeks were reviewed. Cholestasis was defined as a direct serum bilirubin level greater than 2.0 mg/dl during the period of TPN, and other causes of cholestasis were ruled out. RESULTS: Twenty-seven out of 165 VLBWI developed TPN-associated cholestasis with the incidence of 16.4%. Significant risk factors for the development of cholestasis included birth weight, small for gestational age, duration of enteral starvation, duration of parenteral nutrition, septic episodes, necrotizing enterocolitis, and the number of surgery in 30 days of age. Cholestasis occurred at the mean age of 48.8+/-20.7 days and resolved in 53.7+/-8.8 days after onset of cholestasis. The mortality rate of infants with cholestasis was significantly higher than that of infants without cholestasis. Two infants appeared to die of a progressive hepatic dysfunction associated with TPN. CONCLUSION: TPN-associated cholestasis is relatively common in VLBWI, and may progress to the hepatic failure and death. The strategies such as early enteral feeding or the reduction of septic episodes would need to be seriously adopted in order to prevent the morbidity and mortality from TPN-associated cholestasis.

Vasoactive Intestinal Peptide/Pituitary Adenylate Cyclase Activating Peptide Receptor Subtypes in Neuroblastoma, Stomach Cancer / 대한소아혈액종양학회지

PURPOSE: We analyzed the expression of vasoactive intestinal peptide (VIP), pituitary adenylate cyclase activating peptide (PACAP), VIP receptor 1 (VIPR1), VIP receptor 2 (VIPR 2) and PACAP receptor (PACAPR) genes in human neuroblastoma, neuroblastoma cell line, human stomach cancer, and human stomach cancer cell lines using RT-PCR and Sourthern hybridization. The results should permit identification of potential clinical applications for VIP and PACAP. METHODS: We isolated RNA from 1 neuroblastoma cell line, 8 stomach cancer cell lines, 13 neuroblastoma, and 10 stomach cancer tumor specimens. And then we performed RT-PCR, Sourthern hybridization, and sequencing. RESULTS: We detected the RNAs coding for VIP, VIPR1, VIPR2, PACAP, and PACAPR in 1, 11, 2, 12, and 13 out of 13 neuroblastoma tumor specimens, respectively. VIP and PACAPR RNA was expressed in SKNSH. VIPR1 RNA was expressed in 4 of 8 the stomach cancer cell lines and 6 of 10 stomach cancer tumor specimens. CONCLUSION: VIP/PACAP RNA and VIP/PACAP receptors RNA were expressed in SKNSH and neuroblastoma tumor specimens. VIPR1 was expressed in stomach cancer cell lines and tumor specimens. The present results suggested that VIP/PACAP analogues could be a candidate as the growth inhibitor of neuroblastoma and stomach cancer.

Clinical Trial of Vitamin A Supplementation in Very Low Birth Weight Infants at Risk for Chronic Lung Disease / 대한주산의학회잡지

No abstract available.

Complete Sternal Cleft / 대한흉부외과학회지

Congenital defects of the sternum are rare development anomalies. They result form the failure of the lateral sternal bars to fuse. This malformation may be associated with other ventral midline fusion defects and ectopia cordis. A complete sternal cleft is the rarest form and less than 10 cases have been reported in the medical literature. Here were report a 3-day-old boy with complete sternal cleft without other malformations, who underwent primary surgical repair. Surgical correction of complete sternal cleft should be performed in neonatal period whether the infant if symptomatic or not because it is usually simple, able to achieve good result and primary repair is usually feasible at this period.

A Case of Joubert Syndrome Associated with Endstage Renal Disease and Meningocele

Joubert syndrome is an autosomal recessive disorder characterized by cerebellar vermis hypoplasia, hypotonia, developmental delay and either abnormal respiratory pattern(neonatal episodic tachypnea, or apnea), or altered eye movements. We describe a girl with Joubert syndrome associated with multicystic renal dysplasia and meningocele. The clinical and pathological findings of this patient included hypoplasia of the cerebella vermis, bilateral multicystic kidney, hepatic fibrosis, occipital meningocele, severe visual impairment from early infancy, profound psychomotor retartdation, hypotonia, nystagmus and progressive chronic renal insufficiency. Continuous peritoneal dialysis and medical control of azotemia, hyperkalemia and hypertension was instituted immediately. Concomitant malformation of these systems are likely based upon their common developmental and genetic features.

A Study on Iron Status and Anemia of Rural and Urban Middle School Students in Ulsan / 대한소아혈액종양학회지

PURPOSE: This study was aimed at assessing the difference of the prevalence of iron deficiency and iron deficiency anemia among rural and urban middle school students in relation to dietary habit. METHODS: With a questionnaire, blood samples were obtained from 439 apparently healthy rural and urban middle school students residing in Ulsan. Anemia was defined as hemoglobin level of 12.6 g/dL or less for boys and 11.9 g/dL or less for girls. Iron deficiency was defined as serun ferritin level less than 12 micrograms/L or/and transferrin saturation less than 14%. Iron deficiency anemia was defined as iron deficiency plus low hemoglobin. RESULTS: 1) In boys, the prevalence rate of anemia was 17.2%. Among these anemias, 5.4% were found to be iron deficiency anemia. In girls, the prevalence of anemia increased with age. The prevalence of iron deficiency anemia was 6.9%. 2) In girls, the prevalence rate of anemia in rural area was higher than that of anemia in urban area (12.6% in rural, 6.1% in urban, P<0.01). 3) The prevalence of anemia and iron deficiency in the students with menstruation was 10.6% and 33.1%, which was higher than the prevalence of 2.5% and 7.5% in those who did not have the menarche (P<0.001 and P<0.001, respectively). 4) Dietary intake of rural and urban middle school students was estimated lower in energy, iron than the recommeded dietary allowance (RDA). In girls, dietary intake of rural middle school students was estimated lower in iron, niacin, and vitamin C than that of urban middle school students. 5) Nutritional factors such as energy, carbohydrate, protein, and phosphorus showed positive correlation with RBC, hemoglobin (P<0.05). CONCLUSION: It is recommended to enforce the nutritional education to take enough iron in middle school students to reduce the high prevalence rate of anemia among pubertal students.

Antenatal Thyrotropin-Releasing Hormone to Prevent Respiratory Distress Syndrome in Preterm

PURPOSE: The purpose of this study was to assess the efficacy of antenatal thyrotropin-releasing hormone(TRH) given to mothers at risk for preterm delivery and assess various neonatal outcomes in infants born to these mothers. METHODS: Sixty-one mothers(TRH+Dexamethasone(D):30, D:31) with preterm labor at 26-34 weeks of gestational age were randomized into a study group which received 400microgram of TRH at 8 hour interval intravenously(maximum doses of 6) along with 6 mg of D at 12 hour interval intravenously(maximum doses of 4) and into a control group that received the same regimen of D only. Among 61 mothers, 17 mothers(TRH+D:8, D:9) underwent amniocentesis to document changes in L/S ratio and lamellar body count before and after TRH and or D therapy. Thyroid function tests(TFT's) were obtained from infants born at/shortly after birth, near first week and second week of life. RESULTS: Incidences of respiratory distress syndrome(42% vs 30%) and chronic lung disease(56% vs 44%) were not statistically different between the two groups. In fact, greater risk for ventilation at 28 days was observed in infants born within 24 hours of TRH treatment. All other neonatal outcomes except pulmonary hemorrhage(0% vs. 16%) were similar between TRH+D and D groups. TFT of infants born to mothers who received the last mean duration of TRH at 178 hours were similar between the two groups. CONCLUSION: Antenatal administration of TRH in addition to D did not have any additional beneficial effects compared to giving D alone.

Hematologic Characteristics of Neonates Born to Pregnancy-Induced Hypertensive Mothers

PURPOSE: To determine clinical and hematological characteristics of infants born to pregnancy-induced hypertensive mothers and whether neutropenia in these infants is associated with an increased incidence of neonatal sepsis. METHODS: A retrospective study was conducted from June 1995 to June 1997 in 84 infants of pregnancy-induced hypertensive mothers who were admitted to the neonatal intensive care unit of Asan Medical Center. These infants were divided into 2 groups according to their absolute neutrophil counts(Group I: with neutropenia, Group II: without neutropenia) and their clinical, hematological and maternal characteristics were compared between these groups. RESULTS: 1) Infants in Group I were smaller, younger, and delivered more by cesarean section than in infants in Group II. 2) Neutropenia was observed in 77,7% of infants who were less than 30 weeks of gestational age and less than 1,500 g. Neutropenia and thrombocytopenia seem to be a transient phenomenon improving spontaneously approximately after 5.8 days and 8-10 days, respectively. 3) Sex, 1 min apgar score, type of delivery and initial use of antibiotics differ between these 2 groups. 4) There was no apparent increased risk for development of neonatal sepsis associated with neutropenia. CONCLUSION: Neutropenia and thrombocytopenia were observed in 40-50% infants born to pregnancy-induced hypertensive mothers. Such finding was more pronounced in infants whose gestational age was less than 32 weeks and birth weight was less than 1,500 g occuring at 70-80%. Neutropenia, per se, is not associated with increased incidence of sepsis but changes in hematological findings and clinical evidence is more important in predicting sepsis in these infants.

A Case of Epidermolysis Bullosa Herpetiformis

Epidermolysis bullosa (EB) is a rare inherited disease characterized by vesiculobullous lesion that arise in response to minimal trauma or shearing force to the skin. Epiderrnolysis bullosa herpetiformis-Dowling Meara, a variant of EB, has its onset at birth and can be a life threatening disease as it was in this case. We report a case of epidermolysis bullosa herpetiformis in a newborn with a generalized intraepidermal blisters noted at birth whose diagnosis was confirmed by electron microscope. A brief review of the literature is included.

Outbreak of Nosocomial infection caused by Klebsiella pneumoniae Producing Extended-spectrum beta-Lactamase in a Neonatal intensive care unit / 병원감염관리

BACKGROUND: Over the decade, Klebsiella pneumoniae resistant to broad-spectrum oephalosporins have been involved in hospital outbreaks, particulaly in intensive care units. Betwem March 20 and June 12. 1900. an outbreak of sepsis caused by multiresistant K. pneumoniae in the neonatal intensive care unit (NICU) of Asan Medical Center. This paper describes bacteriologic, molecular and epidemiologic features of the outbreak. METHODS: For surveillance purpose, stool specimens were obtained from all patients, nurses and house staff in NICU and cultured onto MacConkey agar medium containg cefotaxim, (10 microgram/ml). All K. pneumoniae isolated blood culture isolates form patients with sepsis were tested for antobiogram by microbroth dilution method and for detection of extended-spectrum beta-Iactamase (ESBL) by double disk synergy test and ESBL Etest. Restriction profiles of total genomic DNAs were compared by pulsed filed gel electrophoresis(PFGE) after cleavage by Xbal. beta-Lactamase was tested using nitroefin disks and characterized by transconjugation to Escherichia coli and isoelectric focusing. For infection control, all infected or colonized patients and nurses were cohorted into a separate room and strict barrier precautions were enforced. RESULTS: The outbreak involved 7 patients with sepsis form whom multiresistant. K. pneumoniae were isolated. Surveillance culture revealed that 9 of 37 patients and 2 of 48 nurses and house staff were colonized. The 18 isolates showed 8 different antimicrobial resistance patterns with cefotaxime resistance in all. Test for ESBL was positive in all 18 isolates but only 15 isolates by ESBL Etest. PFGE analysis showed that 6 of the 7 blood isolate from infected patient and 9 of the 11 fecal isolates from surveillance cultures were of the identical or very similar pattern. beta-Lactamase activities were transferable by conjugation in all but one isolate. No additional case of multiresistant. K. pneumoniae infection had been reproted for 6 months since the introduction of strict barrier precautious and other infection control measures. CONCLUSION: The outbreak was caused by ESBL-producing K. pneumoniae which appeared to be introduced into the NICU from multiple sources as was indicated by PFGE patterns. An optimal laboratory method for screening for ESBL remain to be developed as the double disk synergy test and ESBL Etest did not show complete agreement. As for infoction control our results emphasize the necessity of early recognition of outbreaks, cohorting of not only infected but also colonized patients and reinforcement of the barrier precuations for the prevention of further spread of cross-infections.