Preliminary study on the immunogenicity of a newly developed GCC Tdap vaccine and its protection efficacy against Bordetella pertussis in a murine intranasal challenge model

PURPOSE: Active reduced dose tetanus-diphtheria-acellular pertussis (Tdap) vaccination for adolescents and adults is necessary because waning immunity after primary diphtheria-tetanus-pertussis vaccination is related to the recent emergence of pertussis. This study was conducted to compare the immunogenicity and protection efficacy against Bordetella pertussis between a new GCC Tdap vaccine and a commercially available Tdap vaccine in a murine model. MATERIALS AND METHODS: BALB/c mice were immunized with two doses of diphtheria-tetanus-acellular pertussis (DTaP) vaccine for priming and a subsequent Tdap booster vaccination. According to the type of booster vaccine, mice were divided into four groups: commercially available Tdap vaccine in group 1 and GCC Tdap vaccines of different combinations of pertussis antigens in groups 2 to 4. Humoral and cell-mediated immune responses and protection efficacy using a murine intranasal challenge model after booster vaccination were compared among the four groups. RESULTS: Every group showed significant increases in antibody titers against pertussis antigens such as pertussis toxin, filamentous hemagglutinin, and pertactin after booster vaccination. Spleen cells showed both Th1 and Th2 cell-mediated immune responses stimulated by pertussis antigens in all groups without any significant difference. In the intranasal B. pertussis infection model, bacteria were eradicated in all groups five days after challenge infection. CONCLUSION: This preliminary study did not show significantly different immunogenicity or protection efficacy of the new GCC Tdap vaccines compared to the commercially available Tdap vaccine, although a more extensive study is necessary to assess the differing efficacies of the new GCC Tdap vaccines.

Etiology of Invasive Bacterial Infections in Immunocompetent Children in Korea (1996-2005): A Retrospective Multicenter Study

The purpose of this study was to identify the major etiological agents responsible for invasive bacterial infections in immunocompetent Korean children. We retrospectively surveyed invasive bacterial infections in immunocompetent children caused by eight major pediatric bacteria, namely Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species that were diagnosed at 18 university hospitals from 1996 to 2005. A total of 768 cases were identified. S. agalactiae (48.1%) and S. aureus (37.2%) were the most common pathogens in infants younger than 3 months. S. agalactiae was a common cause of meningitis (73.0%), bacteremia without localization (34.0%), and arthritis (50%) in this age group. S. pneumoniae (45.3%) and H. influenzae (20.4%) were common in children aged 3 months to 5 yr. S. pneumoniae was a common cause of meningitis (41.6%), bacteremia without localization (40.0%), and bacteremic pneumonia (74.1%) in this age group. S. aureus (50.6%), Salmonella species (16.9%), and S. pneumoniae (16.3%) were common in older children. A significant decline in H. influenzae infections over the last 10 yr was noted. S. agalactiae, S. pneumoniae, and S. aureus are important pathogens responsible for invasive bacterial infections in Korean children.

The Causative Organisms of Bacterial Meningitis in Korean Children in 1996-2005

Bacterial meningitis remains a serious cause of morbidity and mortality in childhood, despite the availability of effective vaccines against Haemophilus influenzae type b (Hib) or Streptococcus pneumoniae. The purpose of this study was to analyze data on bacterial meningitis cases in Korea from 1996 through 2005. The information of all hospitalized bacteria-proven meningitis cases was obtained from 17 university hospitals nationwide. A total of 402 cases were identified. Of these, 125 (29.9%) cases were neonates. Streptococcus agalactiae was the most common bacteria responsible for 99 (24.6%) of all cases regardless of age, followed by S. pneumoniae for 91 (22.6%) and H. influenzae for 67 (16.7%) patients. The common etiology beyond the neonatal period was S. pneumoniae for 91 (33.0%) followed by H. influenzae for 63 (22.8%) patients. The overall case fatality rate was 9.4%, which was similar with that in 1986-1995. In conclusion, S. agalactiae, S. pneumoniae and H. influenzae were important etiologic agents of bacterial meningitis in children in the last 10 yrs. It is required to establish the preventive strategy of the three bacteria. The nationwide epidemiologic study should be continued to evaluate immunization strategy and efficacy.

Clinical and Phylogenetic Characteristics of Escherichia coli Urinary Tract Infections / 소아감염

PURPOSE: We aimed to investigate the clinical and phylogenetic characteristics of Escherichia coli Urinary Tract Infections (E. coli UTI). METHODS: We enrolled patients with culture-proven E. coli UTI, who were admitted at the study hospital from September 2008 to August 2009. We investigated clinical data of patients with E. coli UTI and characteristics of isolated E. coli strains. The phylogenetic groups were classified using triplex polymerase chain reaction (PCR), and the distribution of nine virulent genes was determined by multiplex PCR. RESULTS: A total of 47 patients have participated in this study. Thirty (63.8%) were under 6 months; eight (17.0%) were between 6-12 months; and nine (19.1%) were over 12 months. We compared two age groups between under 6-month and over 6-month. In the age group under 6-month, higher proportion of male (P=0.002) and group B2 strains (P=0.020) were observed. In contrast, higher proportion of female and group non-B2 strains were observed in age group over 6-month. Frequencies of papC, papGII, papGIII, sfa/foc, hlyC, cnf1, fyuA, iroN and iucC were estimated as 68.1%, 57.4%, 42.6%, 46.8%, 46.8%, 31.9%, 87.2%, 48.9% and 63.8%, respectively. In the comparison of phylogenetic groups, group B2 showed higher distribution of virulent genes, while group D included more strains resistant to trimethoprim/sulfamethoxazole (TMP/SMZ) than other groups. CONCLUSION: We showed the age group-specific difference in the distribution of sex ratios and phylogenetic groups; more male and group B2 strains in age group under 6-month, while more female and group non-B2 in age group over 6-month. However, further evaluation including larger number of patients will be necessary to confirm above thesis in future molecular epidemiological studies.

Immunogenicity, Reactogenicity and Safety of a Combined DTPa-IPV Vaccine Compared with Separate DTPa and IPV Vaccines in Healthy Korean Infants / 소아감염

PURPOSE: To compare immunogenicity and reactogenicity of a combined diphtheria-tetanus-acellular pertussis-inactivated poliovirus vaccine (DTPa-IPV, Infanrix(TM) IPV, GlaxoSmithKline Biologicals) with co-administration of commercially available DTPa and IPV vaccines at separate injection sites (DTPa+IPV). METHODS: A total of 458 infants aged 8-12 weeks were randomized to receive three-dose primary vaccination at 2, 4 and 6 months with DTPa-IPV or DTPa+IPV. Blood samples were collected pre and post vaccination for measurement of immune responses. Reactogenicity was assessed following each dose using diary cards. RESULTS: One month post-dose 3, seroprotection rates for anti-diphtheria, anti-tetanus and anti-poliovirus types 1, 2 and 3 were > or =99.5% and vaccine response rates to pertussis antigens were at least 98.6% in both DTPa-IPV and DTPa + IPV groups. Non-inferiority between the groups was demonstrated based on pre-defined statistical criteria. Incidences of both local and systemic symptoms were within the same range across both groups with grade 3 symptoms reported following no more than 4.3% of DTPa-IPV doses and 4.5% of DTPa + IPV doses. Two serious adverse events (both pyrexia) after DTPa-IPV administration were considered vaccine-related. Both infants recovered fully. CONCLUSION: Combined DTPa-IPV vaccine was immunogenic and well tolerated when used as a three-dose primary vaccination course in Korean infants. DTPa-IPV could be incorporated into the Korean vaccination schedule, reducing the number of injections required to complete primary immunization.

Upper Respiratory Infections in Children

Upper respiratory tract infection is one of the most common illnesses affecting children. On average, children experience around six to eight upper respiratory tract infections (URTIs) each year. Although these infections usually are mild and self limiting, they occasionally lead to complications that can be life threatening. Most URTIs can be placed within four main categories of infection: nasopharyngitis, pharyngitis, sinusitis and otitis media. Within each category of illness, there is a range of related conditions that may have similar or overlapping clinical presentations. A sound judgment is required to determine the most affected part of the respiratory mucosa. The clinical features, diagnosis and treatment of URTIs in children will be reviewed here.

A Survey for Understanding of Breastfeeding among Mothers with Chronic Hepatitis B Infection / 소아감염

PURPOSE: Breastfeeding should be recommended for infants born to mothers with chronic hepatitis B Infection after postexposure prophylaxis. However, high proportion of these mothers are reluctant to engage in breastfeeding in Korea. This survey was taken to identify the cause of that reluctance. Method:Questionnaires were given to mothers with chronic hepatitis B infection who were registered at the 'Hepatitis B Perinatal Transmission Prevention Program' operated by Korea Center for Disease Control and Prevention. They visited a community health center for blood sample collection and signed a consent paper. The questionnaires were sent to the mothers. Result:Among 839 mailed questionnaires, 114 were returned marked 'address unknown'. The overall reply rate was 17% (n=125). Among responders, 52% (n=62) were breastfeeding and 48% (n=60) were formula-feeding. The most influential factor for breastfeeding was the mother's own decision (75%) and the obstetrician's recommendation (17%). For formula- feeding mothers, their decisions were influenced by obstetricians (57%), and by their own thinking (28%). The relationship between breastfeeding and perinatal prophylaxis failure was recognized as 45% 'related' and 50% 'not-related'. A total of 91% of breastfeeding mothers replied that they will breast-feed again. Among formula-feeding mothers, 78% answered that they will breast-feed if they were known that 'there is no direct relationship between breastfeeding and perinatal prophylaxis failure'. Conclusion:Despite the fact that there is no direct relationship between breastfeeding and perinatal prophylaxis failure, many were reluctant to breast-feed. Healthcare professionals have influence over the mothers for decision making. It will be necessary to educate healthcare personnel so that they can make a conceptual change as well as to promote the fact to the general public.

The use of fluoroquinolone in children / 소아과

The fluoroquinolones are an important group of antibiotics widely used in the treatment of various infectious diseases in adults, as a result of an excellent spectrum of activity, good tissue penetration and convenient ways of administration. In recent decades, there has been extensive development, clinical investigation, licensure and use of fluoroquinolone antibiotics. However, the use of fluoroquinolones in children has been limited because of their potential to induce arthropathy in juvenile animals. Despite class label warnings against use in children, prescriptions for quinolone antibiotics to treat infections in children have become increasingly prevalent. The main use of fluoroquinolones in pediatrics should be, understandably, in serious life-threatening infections for which other antibiotics therapies are not effective or available. While most of the published studies failed to detect an increased rate of articular adverse effects in children treated with fluoroquinolones, an increase in the use of these compounds, particularly in community-acquired lower respiratory infections, could accelerate the emergence of multidrug-resistant (including fluoroquinolone) pneumococcal strains. This review will discus the main issues related to the use of fluoroquinolones in children, the major problems of resistance developing among these compounds, with special emphasis on the potential side effects and skilled use of these alternative potent drugs in pediatric infection.

Provisional update on varicella vaccination in Korea, 2008 / 소아과

No abstract available.

The immunogenicity and reactogenicity of Td booster vaccination in Korean preadolescents, aged with 11-12 years old / 소아과

PURPOSE: This study was undertaken to evaluate the immunogenicity and reactogenicity of Td booster immunization in early preadolescents of Korea. METHODS: Healthy preadolescents, who had been vaccinated with 4 or 5 doses of DTaP vaccines until 6 years old age, were enrolled in this study from August 2006 to April 2007 . Diphtheria and tetanus anti-toxoid antibodies in sera were measured by ELISA just before vaccination and 4 weeks after vaccination to evaluate immunogenicity. Local and systemic adverse reactions observed for 4 weeks after vaccination to access reactogenicity. RESULTS: 183 preadolescents were enrolled and mean age was 11.40+/-0.51 years old. All subjects achieved seroprotective diphtheria and tetanus anti-toxoid antibodies (titers > or =0.1 IU/mL) after Td booster vaccination. Among 183 vaccinees, 73.8% showed local adverse reactions and 37.2% systemic adverse reactions. Pain at injection site (66.1%) was the most common local reaction, and the most commonly shown systemic reaction was myalgia (17.5%). The adverse reactions were spontaneously relieved within three days after vaccination. CONCLUSION: Td vaccine in this study was high immunogenic and showed an acceptable tolerance in Korean preadolescents. Td booster vaccination at 11 -12 years old is the most effective method to increase compliance of the vaccination and to decrease the incidence of diphtheria and tetanus.

Susceptibility tests of oral antibiotics including cefixime against Escherichia coli, isolated from pediatric patients with community acquired urinary tract infections / 소아과

PURPOSE: Urinary tract infection(UTI) is one of the most frequent infections in children. E. coli is the most frequent etiological micropathogen in pediatric community UTI, and E. coli has developed resistance to many antibiotics, highlighting the need for regular surveys of this organism resistant patterns in the community. The aim of this study was to determine the oral antibiotic susceptibility patterns of E. coli, isolated from pediatric patients with uncomplicated community acquired UTI. METHODS: E. coli isolates, obtained from pediatric patients with uncomplicated community acquired UTI between October in 2004 to September in 2005. And minimal inhibitory concentrations(MICs) of oral aminopenicillins and beta-lactamase inhibnitors(ampicillin, amoxacillin, ampicillin-sulbactam), oral cephalosporins(cefaclor, cefixime) and sulfa drug(trimethoprime-sulfamethoxazole) were performed according to the National Committee for Clinical Laboratory Standards(NCCLS) guide line. RESULTS: Total 211 organisms were isolated from pediatric out-patients with community UTI. E. coli was the most common organism(89 percent), followed by E. fecalis, Proteus species, S. aureus, M. morganii, and P. aeruginosa. The resistant rates of aminopenicillins and beta-lactamase inhibitors, cefaclor and sulfa drug to E. coli were very high. But, the resistant rate of cefixime was markedly low, and ESBL strains were isolated with small rates. CONCLUSION: Our study results suggest that aminopenicillins, cefaclor and sulfa drug may not be useful as first line empirical antibiotics to treat pediatric patients with community UTI in Korea. But, 3rd generation cephalosporin such as cefixime can be used as effective second line antibiotics after primary treatment failure, also may be useful as an empirical first line antibiotic. Finally, we conclude that a continuous surveillance study to monitor susceptibility patterns of E. coli in community UTI will be needed for the standard guide lines of empirical oral antibiotic treatment.

A Korean Family of Hypokalemic Periodic Paralysis with Mutation in a Voltage-gated Calcium Channel (R1239G)

Hypokalemic periodic paralysis (HOPP) is a rare disease characterized by reversible attacks of muscle weakness accompanied by episodic hypokalemia. Recent molecular work has revealed that the majority of familial HOPP is due to mutations in a skeletal muscle voltage-dependent calcium-channel: the dihydropyridine receptor. We report a 13-yr old boy with HOPP from a family in which 6 members are affected in three generations. Genetic examination identified a nucleotide 3705 C to G mutation in exon 30 of the calcium channel gene, CACNA1S. This mutation predicts a codon change from arginine to glycine at the amino acid position #1239 (R1239G). Among the three known mutations of the CACNA1S gene, the R1239G mutation was rarely reported. This boy and the other family members who did not respond to acetazolamide, showed a marked improvement of the paralytic symptoms after spironolactone treatment.

The Safety and Immunogenicity of a Trivalent, Live, Attenuated MMR Vaccine, Priorix (TM) / 소아과

PURPOSE: This multi-center, open-label, clinical study was designed to evaluate the safety and immunogenicity of a trivalent, live, attenuated measles-mumps-rubella (MMR) vaccine, Priorix (TM) in Korean children. METHODS: From July 2002 to February 2003, a total of 252 children, aged 12-15 months or 4-6 years, received Priorix (TM) at four centers: Han-il General Hospital, Kyunghee University Hospital, St. Paul's Hospital at the Catholic Medical College in Seoul, and Korea University Hospital in Ansan, Korea. Only subjects who fully met protocol requirements were included in the final analysis. The occurrence of local and systemic adverse events after vaccination was evaluated from diary cards and physical examination for 42 days after vaccination. Serum antibody levels were measured prior to and 42 days post-vaccination using IgG ELISA assays at GlaxoSmithKline Biologicals (GSK) in Belgium. RESULTS: Of the 252 enrolled subjects, a total of 199 were included in the safety analysis, including 103 from the 12-15 month age group and 96 from the 4-6 year age group. The occurrence of local reactions related to the study drug was 10.1 percent, and the occurrence of systemic reactions was 6.5 percent. There were no episodes of aseptic meningitis or febrile convulsions, nor any other serious adverse reaction. In immunogenicity analysis, the seroconversion rate of previously seronegative subjects was 99 percent for measles, 93 percent for mumps and 100 percent for rubella. Both age groups showed similar seroconversion rates. The geometric mean titers achieved, 42 days post- vaccination, were: For measles, in the age group 12-15 months, 3, 838.6 mIU/mL [3, 304.47, 4, 458.91]; in the age group 4-6 years, 1, 886.2 mIU/mL [825.83, 4, 308.26]. For mumps, in the age group 12-15 months, 956.3 U/mL [821.81, 1, 112.71]; in the age group 4-6 years, 2, 473.8 U/mL [1, 518.94, 4, 028.92]. For rubella, in the age group 12-15 months, 94.5 IU/mL [79.56, 112.28]; in the age group 4-6 years, 168.9 IU/mL [108.96, 261.90]. CONCLUSION: When Korean children in the age groups of 12-15 months or 4-6 years were vaccinated with GlaxoSmithKline Biologicals' live attenuated MMR vaccine (Priorix (TM) ), adverse events were limited to those generally expected with any live vaccine. Priorix (TM) demonstrated excellent immunogenicity in this population.

The Incidence Rate of Hepatitis B Virus Surface Gene Variants in Korean Children with Immunoprophylaxis Failure of Perinatal Infection / 대한간학회지

BACKGROUND/AIMS: Perinatal infection with hepatitis B virus (HBV) may occur despite immunoprophylaxis. One of the important mechanisms for perinatal prophylaxis failure, might include HBV surface gene variants. Therefore, we screened Korean children, in whom perinatal prophylaxis failed, for HBV surface gene variants. METHODS: Thirty-one children with perinatal HBV prophylaxis failure were selected. To amplify the major hydrophilic region of the HBV surface gene, nested PCR with primers targeted to nucleotides 237 to 706 was performed, and then sequencing was done. RESULTS: All cases were shown to be PCR positive for HBV-DNA and genotype C. Nine out of 31 (29%) with perinatal prophylaxis failure had a nucleotide substitution at the major hydrophilic region of the gene; but only two cases (6.5%) had an amino acid substitution. One case was infected by wild type and variants of I126S, and the other by wild type and S114A+I126S, respectively. CONCLUSIONS: In Korea, compared to the previous studies of other nations, gene surface variants such as G145R do not appear to play an important role in perinatal immunoprophylaxis failure.

Epidemiological Study of Pneumococcal Nasal Carriage and Serotypes Among Korean Children / 소아과

PURPOSE: The aim of this study was to determine the prevalence of pneumococcal nasal carriage and confirm the distribution of pneumococcal capsular serotypes in Korean children below aged 5 years old. Another reason this study was performed was to identify the theoretical coverage by seven valent conjugate pneumococcal vaccine, and confirm the penicillin resistant rate. METHODS: This study included 213 children, who visited out patient clinic or were hospitalized in six hospitals between August 2001 and April 2002. Nasopharyngeal swabs and cultures for S. pneumoniae were performed. Serotyping of isolated samples was performed by the Quellung reaction at the Statens Seruminstitut in Copenhagen. Penicillin MICs were determined by the agar dilution method, and interpreted according to the NCCLS guide line. RESULTS: The prevalence of pneumococcal nasal carriage rate in this study was 34.3%. A total of 31 of 73 isolates(42.5%) had intermediate resistance to penicillin, and 29 of 73 isolates(39.7%) showed a high resistance to penicillin. The predominant serotype of the S. pneumoniae isolates was 23F(22%), and the percentages of vaccine serotypes(46.6%) and associated serotypes(37%) which belong to the seven-valent pneumococcal conjugate vaccine were 83.6%. The resistance pattern of pneumococcal isolates to penicillin was different among the serotypes. CONCLUSION: Pneumococcal isolates from nasal colonization of Korean children showed a high penicillin resistant rate. We assumed that newly developed seven-valent pneumococcal conjugate vaccine may offer a high theoretical coverage for the isolated strains.

Associations of HLA Alleles with Chronic Infection and Prophylaxis in Vertical Transmission of Hepatitis B Virus

Perinatal transmission and infection of hepatitis B virus (HBV) in early childhood were observed in the offsprings of hepatitis B surface antigen (HBsAg)-positive mothers who had been vaccinated against HBV immediately after giving birth. This prophylaxis failure of perinatal HBV infection is likely due to the interplay of the virus and host immune response. To investigate whether the HLA polymorphism affected the outcome of the perinatal prophylaxis, HLA class I (HLA-A, B and Cw) and class II (HLA-DRB1, DQA1, DQB1 and DPB1) were typed using serology, PCR-SSOP (polymerase chain reaction-sequence specific oligonucleotide probe), and PCR-ARMS (amplification refractory modification system) methods in 22 HBeAg-positive mothers and their 10 prophylaxis-succeeded and 12 prophylaxis- failed children. The HLA types of the mothers and their children were compared with 198 HBsAg-negative healthy controls in a Korean population. HLA-B35 (relative risk=4.2, p<0.01), B51 (relative risk=3.2, p<0.02), DRB1*07 (relative risk=3.8, p<0.03), and DQA1*02 (relative risk=3.8, p<0.03) alleles were more frequent in HBeAg-positive mothers than in the controls. Also, HLA-DRB1*13 (relative risk=0.1, p<0.02) and DPB1*0401 (relative risk=0.1, p<0.02) alleles were less frequent in HBeAg-positive mothers. However, HLA alleles did not affect the outcome of the perinatal prophylaxis against HBV. These results suggest that the reported influences of some HLA alleles on the natural chronic HBV infections may not operate in the HBV infections in children received perinatal prophylaxis.

Antimicrobial Activities of Tapocin(r) against Gram-Positive Cocci / 감염과화학요법

BACKGROUND: Recent hospital environments have changed, and the most common and important causative agents of nosocomial infections are Gram positive organisms, such as staphylococci, streptococci and enterococci. And increasing resistance of such Gram-positive organisms to antimicrobials, including glycopeptides, is causing big problems in hospital infections. Therefore, we confirmed and compared the antimicrobial activities of glycopeptides [Tapocin(r) (CJ Pharmaceutics. Korea), vancomycin, teicoplanin] against clinical isolates of streptococci(PSSP, PNSSP), staphylococci (MSSA, MRSA, MRCNS) and enterococci. METHODS: Total 666 strains of Gram-positive cocci, collected in five Catholic University affiliated Hospitals were tested by broth microdilution method using Muller-Hinton broth according to the recommendation of NCCLS (National Committee for Clinical Laboratory Standard, USA). RESULTS: In PSSP (n=46), MIC range of vancomycin was 0.25-0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.015-0.06 microgram/mL. MIC90 of vancomycin was 0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06 microgram/mL. In PNSSP (n=123), MIC range of vancomycin was 0.25-0.5 microgram/mL, and MIC range of Tapocin(r) and teicoplanin was equally 0.03-0.06 microgram/mL. The MIC range of vancomycin against MSSA (n=116) was 2-4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.5-8 microgram/mL. MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 2 microgram/mL. In MRSA (n=116), MIC range of Tapocin(r) and teicoplanin was equally 0.25-8 microgram /mL, showing broader range distribution than that of vancomycin (2-4 microgram/mL). MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 8 microgram/mL. MIC range against MRCNS (n=14) of vancomycin was 0.25-8 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06- 16 microgram/mL. In enterococci (n=123), the MIC range of vancomycin was 0.5-64 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.25-64 microgram/mL. MIC90 of all antibiotics was 8 microgram/mL, but 6 E. faecium resistant to all antibiotics were detected. CONCLUSION: The results of susceptibility tests showed that the against glycopeptides against Gram- positive cocci, which were isolated in our study university hospitals, seem to be largely unaffected. We also confirmed that the antimicrobial activity of Tapocin(r) was equal to that of teicoplanin.

Antimicrobial Activities of Tapocin(r) against Gram-Positive Cocci / 감염과화학요법

BACKGROUND: Recent hospital environments have changed, and the most common and important causative agents of nosocomial infections are Gram positive organisms, such as staphylococci, streptococci and enterococci. And increasing resistance of such Gram-positive organisms to antimicrobials, including glycopeptides, is causing big problems in hospital infections. Therefore, we confirmed and compared the antimicrobial activities of glycopeptides [Tapocin(r) (CJ Pharmaceutics. Korea), vancomycin, teicoplanin] against clinical isolates of streptococci(PSSP, PNSSP), staphylococci (MSSA, MRSA, MRCNS) and enterococci. METHODS: Total 666 strains of Gram-positive cocci, collected in five Catholic University affiliated Hospitals were tested by broth microdilution method using Muller-Hinton broth according to the recommendation of NCCLS (National Committee for Clinical Laboratory Standard, USA). RESULTS: In PSSP (n=46), MIC range of vancomycin was 0.25-0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.015-0.06 microgram/mL. MIC90 of vancomycin was 0.5 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06 microgram/mL. In PNSSP (n=123), MIC range of vancomycin was 0.25-0.5 microgram/mL, and MIC range of Tapocin(r) and teicoplanin was equally 0.03-0.06 microgram/mL. The MIC range of vancomycin against MSSA (n=116) was 2-4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.5-8 microgram/mL. MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 2 microgram/mL. In MRSA (n=116), MIC range of Tapocin(r) and teicoplanin was equally 0.25-8 microgram /mL, showing broader range distribution than that of vancomycin (2-4 microgram/mL). MIC90 of vancomycin was 4 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 8 microgram/mL. MIC range against MRCNS (n=14) of vancomycin was 0.25-8 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.06- 16 microgram/mL. In enterococci (n=123), the MIC range of vancomycin was 0.5-64 microgram/mL, and that of Tapocin(r) and teicoplanin was equally 0.25-64 microgram/mL. MIC90 of all antibiotics was 8 microgram/mL, but 6 E. faecium resistant to all antibiotics were detected. CONCLUSION: The results of susceptibility tests showed that the against glycopeptides against Gram- positive cocci, which were isolated in our study university hospitals, seem to be largely unaffected. We also confirmed that the antimicrobial activity of Tapocin(r) was equal to that of teicoplanin.

Typing of Epstein-Barr Virus in Children with Febrile Illness and Malignancies / 감염

BACKGROUND: The Epstein-Barr virus (EBV) is a human DNA herpesvirus that causes worldwide spread. Primary infection of EBV in early childhood is often subclinical, and more than 90% of children older than five years of ages are seropositive for EBV in Korea. Two types of EBV have been described which differ in their geographical distributions and associated diseases. Variable diseases including many malignancies are associated with EBV infections. And the pathogenesis of EBV associated diseases are very complicated. To study EBV typing in EBV associated diseases could be the first step to find out the pathogenesis of EBV associated diseases, and to confirm the altered reactivation and typing of EBV under various disease conditions may be indirectly helpful to understand the pathogenesis of EBV associated diseases. In this aspect, we performed this study. METHODS: The study group included 90 children (age range 1 to 15 years) with febrile illness and malignancies who had serologic evidence of previous EBV infection. Sixty-two cases of the study group had febrile illness and 28 cases had malignancies. Febrile illness groups were classified into bacterial infection, non-bacterial infection and Kawasaki disease. The control group included 62 healthy children in the range of 5 to 15 years of age. Mouth washing samples were taken and two types, EBV A and B were identified by using one-step PCR. B95-8 cells (type A) and Jijoye cells (type B) were used as positive controls, and K-562 cells was used as a negative control. RESULTS: The results were as follows; Eleven (17.7%) of the 62 healthy children had EBV DNA in throat washings : of these, 8 (72.7%) were shedding type A virus, and 3 (27.3%) type B. EBV was detected in 12 (57%) of the 21 patients with bacterial infection : 7 (58.3%) had A type, 2 (16.7%) B type, and 3 (25%) both types. 23 (79.3%) of the 29 patient with non-bacterial infection had EBV DNA in throat washing: of these, 15 (65.2%) had A type, 4 (17.4%) B type, and 4 (17.4%) both types. Two (16.7%) of the 12 patients with Kawasaki disease had EBV DNA in throat washing; all of them were type A. EBV was detected in 15 of the 28 children with malignancies : 11 (73.3%) had only type A, 2 (13.3%) type B, and 2 (13.3%) both types. Overall, the seropositive rate of study group was significantly higher than that of control group. But, there was no significant difference in seropositive rate between febrile illness and malignancies. Both the seropositive rates in the bacterial infection and non-bacterial infection groups were significantly higher than that of Kawasaki disease group (respectively P<0.001, P<0.001). CONCLUSION: We have the facts and suggestions as followings; We reconfirm that type A EBV is highly dominant and no mixed infection in Korean healthy children. The EBV excretion rate in children with febrile illness or malignancies was about 3-fold higher than that in healthy children, and coinfection with type A and B was seen in both study group. These results suggest that EBV reactivation may be increased in the status of immunologic alteration, induced by diseases. By contrast, EBV reactivation may not be found in certain acute febrile illness like Kawasaki disease, in which immunologic alteration to reactivate EBV is not induced. We think that this study may provide the basis to figure out the pathogenesis of EBV associated diseases. But, The outcome of this study is incomplete and indirect to understand the host immune responses to EBV and pathognomic role according to EBV types. So, further large scaled studies of EBV subtyping using variable methods will be needed to investigate the pathogenesis of EBV associated diseases.

The Incidence of Feeding Intolerance in the Full Term Neonates with Hypoxic-Ischemic Encephalopathy

PURPOSE: We investigated incidence of feeding intolerance and time when normal enteral feeding can be established in full term neonates with hypoxic-ischemic encephalopathy (HIE). METHODS: We reviewed medical records of 61 full term infants with HIE who were admitted to St. Paul's Hospital from Jan. 1996 to Dec. 2001. The incidence of feeding intolerance, day of first feeding, and day of full enteral feeding were studied in respective to Sarnat stages. RESULTS: Among the full term with HIE, 32 were classified into stage I, 20 into stage II, and 9 into stage III. The incidence of feeding intolerance was 6%, 30%, and 89% for stages I, II and III, respectively. There was only one case of necrotizing enterocolitis among infants of stage III HIE. Feeding first began on 0.13+/-0.01 postnatal day (PND) in normal infants compared to 0.15+/-0.03 PND in infants of stage I, 3.24+/-1.82 PND in stage II and 5.58+/-2.50 PND in stage III. The incidence of feeding intolerance, day of first feeding, and day of normal enteral feeding achieved in infants with stage I were not different from those of normal infants but significantly higher and delayed in infants with more severe degrees of encephalopathy. CONCLUSION: The first feeding should vary according to severity of encephalopathy so as to lower the incidence of feeding intolerance and the risk of necrotizing enterocolitis. We suggest that infants of stageIencephalopathy be first fed as same as normal infants, but precaution is in order when deciding an appropriate time to start feeding in infants of stage II, III encephalopathy.