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Nosocomial Staphylococcus aureus fulminant sepsis in a neonatal intensive care: Absence of clonal spread
Abstracts
The aim of the study was to assess IGF-1 influence on PECAM-1 and ICAM-1 adhesion molecules expression on human umbilical endothelial cells (HUVEC).
S67
correlation between ELBW, Gram-negative etiology of n.s. and bad prognosis of ns. in prematures was shown. Birth asphyxia, IVH, PVL, PDA and BPD were often noted in prematures with bad outcome because of n.s.
Materials and methods Conclusions Material for study was obtained from fresh umbilical cord. Cell lines were incubated with IGF-1 concentrations of 50 ng/ml and 200 ng/ml. Ratio of PECAM-1 and ICAM-1 expression revealing cells was obtained using the flow cytometry method. In statistic analysis ANOVA test and Duncan's new multiple range test were used.
Elbw, Gram-negative etiology of nosocomial sepsis as well as birth asphyxia, CNS injuries and chronic lung disease reduce the premature neonates chances of survival. doi:10.1016/j.earlhumdev.2008.09.172
Results It was demonstrated, that IGF-1 concentrations of 50 ng/ml, 200 ng/ml enhance PECAM-1 and ICAM-1 endothelial cells expression (respectively to 57.2 ± 4.8%, 76.1 ± 1.5% and 91.7 ± 5.0%, 86.8 ± 4.7%) compared to control group (respectively: 20.9 ± 0.5% and 26.6 ± 0.5%). Conclusions Insulin-like growth factor-1 enhances PECAM-1 and ICAM-1 adhesion molecules expression on HUVEC cells, activating the endothelium.
Abstract UENPS.157 Neonatal group B ß hemolytic streptococci colonization: Prevalence, serotypes and antimicrobial susceptibility Rasa Tameliene⁎,a, Ruta Nadišauskieneb, Egle Barcaiteb a Department of Neonatology Kaunas Medical University, Lithuania b Department of Obstetrics and Gynecology Kaunas Medical University, Lithuania Background and aim
doi:10.1016/j.earlhumdev.2008.09.171
To determine the prevalence of group B streptococcus (GBS) colonization among newborns, the serotype distribution and antimicrobial susceptibility of GBS isolates, to evaluate GBS transmission from mother to neonate.
Abstract UENPS.156 A ten year study of nosocomial sepsis in preterm neonates treated in the university NICU
Materials and methods
Jakub Behrendt, Malgorzata Stojewska, Jolanta Balicz, Urszula Godula-Stuglik⁎ NICU, Department of Pediatrics, Silesian Medical University, Zabrze, Poland
A prospective cross-sectional study carried out at the Department of Obstetrics and Gynecology and the Department of Neonatology of Kaunas University Hospital. Samples were collected from the lower vagina and the anorectum of pregnant women at 35–37 weeks of gestation or at delivery and from the ear canal and throat of the neonates within 5–15 min of their lives. The distribution of serotypes of the GBS identified was determined using specific antisera and antimicrobial susceptibility was investigated by disc-diffusion method as described by the National Committee for Clinical Laboratory Standards (NCCLS).
Background and aim Determination of morbidity rate of n.s. among prematures admitted to the NICU in Zabrze, analysis of the symptoms and outcome according to the sex, birth weight, gestational age, other perinatal and postnatal risk factors and etiology of nosocomial sepsis (n.s.). Materials and methods Within 10 years (1997–2006) 742 neonates with symptoms of n.s. were admitted to the NICU (26% of all hospitalized neonates), among them 432 (58.2%) prematures. N.s. was diagnosed in 185 (43%) of cases. Neonates comprised 1) those admitted to NICU at the age of 1 or 2 days, who did not show clinical and microbiological symptoms of sepsis, they developed sepsis in the course of treatment and tested positive for the presence of bacteria or in blood, 2) preterms at the age of 5 or more days, born without infection and stayed at other hospital prior to admission to the NICU. They showed clinical symptoms of sepsis and had positive blood cultures. ELBW in 20%, VLBW in 62%, GA < 28 weeks in 28%, IUGR in 12%, severe birth asphyxia in 29% were noted. Mother of septic prematures had abnormal course of pregnancy in 78% and in 75% complications of delivery.
Results GBS colonization was detected in 53 (6.4%) of 827 newborns. Colonization in earth canal was found in 15 (28.3%) of them, in the throat — 9 (17%) and both were recorded in 29 (54.7%) of the newborns studied. The most common serotypes were III (37.7%), Ia (32%), V (9.4%), IV (5.7%), II (5.7%), Ib (3.7%), VI (2.1%) and unidentified (3.7%) All isolates were susceptible to penicillin whereas 3.8% showed resistance to erythromycin. The overall maternal colonization and vertical transmission rates were 15.3% and 28.4%, respectively. Conclusions Neonatal GBS colonisation was estimated similar to those reported from other industrialized countries. The most frequent serotypes identified are III and Ia. Intrapartum antibiotic prophylaxis has been shown to be effective in reducing the incidence GBS colonization in newborns. Standardized strategy for the prevention of early onset GBS disease in the newborn is necessary in Lithuania. doi:10.1016/j.earlhumdev.2008.09.173
Results Clinical symptoms of n.s. included pneumonia (95%), hepatomegaly (82%), gastrointestinal disorders (79%), shock (70%), DIC (32%), meningitis (30%), and pyuria (12%). Abnormal laboratory findings as metabolic acidosis (84%), increase of CRP (89%), WBC > 20.0G/l (46%), leukopenia 4.0 G/l (9%), trombocytopenia (52%), stab cells > 5% (40%), hyperbilirubinemia (15%), and glycemia disorders (20%) were noted. The dominating types of bacteria from the blood were Klebsiella pn. (61), Staph. epid. MR (49) and Pseudomonas aer. (27). Other MR staphylococcal strains (15), S. aureus (8), Streptococcus foecalis (8), Serratia marcescens (7), Enterobacter (6), Acinetobacter baumanii (4) were stated in 26% of n.s. prematures. More than 80% of preterms were intubated before they developed n.s., 94% received TPN, 26% were operated because of congenital defects. Mortality rate was 19.4% (36 cases), a significant
Abstract UENPS.158 Nosocomial Staphylococcus aureus fulminant sepsis in a neonatal intensive care: Absence of clonal spread Elsa Paulino⁎,a, Rosalina Barrosoa, Maria Miragaiab, Maria João Britoa, Luisa Sanchoa, Teresa Conceiçãob, Marta Aires-de-Sousac, Teresa Sardinhaa, Helena Carreiroa, Herminia Lencastred a Fernando Fonseca Hospital, Amadora, Portugal b Instituto de Tecnologia Quimica e Biológica (ITQB), Oeiras, Portugal c Escola Superior da saúde da Cruz vermelha Portuguesa, Lisboa, Portugal d Rockefeller University, New York, United States
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Abstracts
Background and aim Staphylococcus aureus (SA) is a well-known nosocomial pathogen among patients in neonatal intensive care units (NICUs) and is associated with substantial morbidity and mortality. Methicillin-susceptible S. aureus (MSSA) is frequently endemic, but there are reports of clusters of epidemics of disease among hospitalized neonates, both in well-baby nurseries and in NICUs. Materials and methods Retrospective review of clinical file of three patients died with SA infection in a period of a week in the NICU as well as records of active surveillance was performed. The MSSA isolates were characterized by pulsed-field gel electrophoresis (PFGE), and presence of virulence determinants was detected by multiplex PCR. Results In 2005, and within the period of a week three patients were septic with MSSA. The three babies were premature with extremely low birth weight (<1000 g). Two were twins and had late onset sepsis but no major risk factors. The other baby had early onset sepsis (second day of life) and the possible risks were umbilical venous catheter and mechanical ventilation. In all cases the disease was abrupt, and two of them showed signs of necrotizing enterocolitis, disseminated intravascular coagulation, evolution to septic shock and death within 15 to 48 h. One of the twins has a more extended disease with multi organic failure and death in a week. Blood cultures were positive for MSSA in two of the babies only. The isolates were identical by PFGE and positive for the LukE–LukD, gamahemolysin variant, beta-hemolysin and SEL toxic determinants. Active surveillance for SA was performed by culturing the anterior nares of parents and health care workers (HCW) as well as the environment of the NICU, but no identical isolates were found. The outbreak was controlled by enhanced infection control measures.
women (vagina and the rectum swabs). There were 250 GBS positive mothers, which delivered 253 newborns and received (199 women) or not received (51 women) the intrapartum antibiotic prophylaxis (IAP) according to CDC protocol. In 183 cases penicillin was used, in 16 cases it was macrolid. Selected parameters were examined retrospectively and statistically analysed. Results The frequency of the colonization with GBS was 11.4%. In 33 neonates (13%), the intrauterine infection of various etiology and localization was diagnosed. Two children (0.8%) were infected with GBS. The frequency of intrauterine infections in neonates whose mothers received IAP (22/199 cases), was statistically significantly lower than the frequency of infections in newborns whose mothers were not selected for it (11/51 cases), p = 0.036. In the group receiving penicillin statistically significantly lower frequency of intrauterine infection was observed, compared with the group receiving macrolid (8.2% v. 37.5%), p = 0.001. In 99 neonates, ear swab was performed. Positive results were obtained in 17 cases (18%). In 4/17 of positive results, the intrauterine infection occurred. Statistically significant differences between the frequency of the intrauterine infection in the groups of neonates colonized and not colonized with pathogens were not shown. Conclusions 1. 2.
3.
Perinatal prophylaxis against GBS does not completely eliminate infection in neonates. Intrapartum antibiotic prophylaxis is not related to a higher risk of the intrauterine infection of another etiology. Penicillin is a better choice than macrolid. Ear swab does not seem to be of diagnostic value for the neonates of GBS positive mothers.
doi:10.1016/j.earlhumdev.2008.09.175 Conclusions The molecular methods used showed that the strains isolated from the babies, carriers and environment belonged to different clones. Therefore it was not possible to determine the routes of transmission of the strains that caused the three infection episodes. Prompt recognition of the risk of spread within the NICU led to prevention of occurrence of new cases, showing that the implementation of enhanced infection control measures can be effective even in high risk units such as NICUs. doi:10.1016/j.earlhumdev.2008.09.174
Abstract UENPS.160 Abscessus caused by methicillin resistant Staphylococcus aureus in newborns Burbuqe Mustafa-Skenderi⁎, Shala Muje, Shaqiri Florim, Mimoza Alishani Q.K.U.K, Prishtine, Yugoslavia Background and aim Infections with MRSA, in recent time show increased tendency in NICU. Materials and methods
Abstract UENPS.159 Perinatal prophylaxis of group B streptococcal infections — The own experiences Bozena Kociszewska-Najman⁎,a, Anna Oslislob Medical University of Warsaw, Warsaw, Poland b The Higher School of Applied Sciences, Ruda Slaska, Poland
Our objective has been to analyze abscesses of skin and soft tissues at patients hospitalized in NICU in time period 2006–2008, symptomatology, laboratory changes, and therapy. Results
a
In many countries, including Poland, maternal group B streptococcal (GBS) screening program is not implemented. In the Obstetrics and Gynecology Clinic I of the Medical University of Warsaw, in accordance with recommendations of the Centers for Disease Control and Prevention (CDC), prophylaxis strategy has been performed since 01.01.2007. The aim of the study was to evaluate chosen procedures for the mother and the newborn based on the analysis of a type and frequency of intrauterine infection in the neonates of GBS positive mothers.
10 cases have been filed, with abscesses of skin and soft tissues from a total of 900 hospitalized, 5 of them were female and 5 were male, birth weight from 2050 g–3400 g. 2 of them have been premature, average 11 days. Most often localized part has been breast — 5 cases, 1 in thoracic part 2 in gluteal part of body, one in calcaneal part and the other one in parotid glandule. In all cases an incision and drainage of abscess has been made, in microbiological analysis of pus MRSA has been isolated, sensitive to Vankomycine. The rate of PCR has been from 36–96. WBC 6–40; 3 cases has been with hypoalbuminaemia and anaemia, in 4 cases blood culture has been positive for MRSA, 1 case in Klebsiella spec, 1 in Citrobacter and 4 others were negative. Therapy has lasted for 2–3 weeks with Vankomycin, Amikacin, and Ceftriaxon. All hospitalized patients had left the hospital in a good health condition.
Materials and methods
Conclusions
The studied population included 2212 pregnant patients hospitalized from 01.01.2007 to 17.04.2008. Bacterial culture was performed in all pregnant
Infections with MRSA are increasing in NICU, more often are in after first week of life, most often localised part was breast, in 60% it has been followed
Background and aim
The aim of the study was to assess IGF-1 influence on PECAM-1 and ICAM-1 adhesion molecules expression on human umbilical endothelial cells (HUVEC).
S67
correlation between ELBW, Gram-negative etiology of n.s. and bad prognosis of ns. in prematures was shown. Birth asphyxia, IVH, PVL, PDA and BPD were often noted in prematures with bad outcome because of n.s.
Materials and methods Conclusions Material for study was obtained from fresh umbilical cord. Cell lines were incubated with IGF-1 concentrations of 50 ng/ml and 200 ng/ml. Ratio of PECAM-1 and ICAM-1 expression revealing cells was obtained using the flow cytometry method. In statistic analysis ANOVA test and Duncan's new multiple range test were used.
Elbw, Gram-negative etiology of nosocomial sepsis as well as birth asphyxia, CNS injuries and chronic lung disease reduce the premature neonates chances of survival. doi:10.1016/j.earlhumdev.2008.09.172
Results It was demonstrated, that IGF-1 concentrations of 50 ng/ml, 200 ng/ml enhance PECAM-1 and ICAM-1 endothelial cells expression (respectively to 57.2 ± 4.8%, 76.1 ± 1.5% and 91.7 ± 5.0%, 86.8 ± 4.7%) compared to control group (respectively: 20.9 ± 0.5% and 26.6 ± 0.5%). Conclusions Insulin-like growth factor-1 enhances PECAM-1 and ICAM-1 adhesion molecules expression on HUVEC cells, activating the endothelium.
Abstract UENPS.157 Neonatal group B ß hemolytic streptococci colonization: Prevalence, serotypes and antimicrobial susceptibility Rasa Tameliene⁎,a, Ruta Nadišauskieneb, Egle Barcaiteb a Department of Neonatology Kaunas Medical University, Lithuania b Department of Obstetrics and Gynecology Kaunas Medical University, Lithuania Background and aim
doi:10.1016/j.earlhumdev.2008.09.171
To determine the prevalence of group B streptococcus (GBS) colonization among newborns, the serotype distribution and antimicrobial susceptibility of GBS isolates, to evaluate GBS transmission from mother to neonate.
Abstract UENPS.156 A ten year study of nosocomial sepsis in preterm neonates treated in the university NICU
Materials and methods
Jakub Behrendt, Malgorzata Stojewska, Jolanta Balicz, Urszula Godula-Stuglik⁎ NICU, Department of Pediatrics, Silesian Medical University, Zabrze, Poland
A prospective cross-sectional study carried out at the Department of Obstetrics and Gynecology and the Department of Neonatology of Kaunas University Hospital. Samples were collected from the lower vagina and the anorectum of pregnant women at 35–37 weeks of gestation or at delivery and from the ear canal and throat of the neonates within 5–15 min of their lives. The distribution of serotypes of the GBS identified was determined using specific antisera and antimicrobial susceptibility was investigated by disc-diffusion method as described by the National Committee for Clinical Laboratory Standards (NCCLS).
Background and aim Determination of morbidity rate of n.s. among prematures admitted to the NICU in Zabrze, analysis of the symptoms and outcome according to the sex, birth weight, gestational age, other perinatal and postnatal risk factors and etiology of nosocomial sepsis (n.s.). Materials and methods Within 10 years (1997–2006) 742 neonates with symptoms of n.s. were admitted to the NICU (26% of all hospitalized neonates), among them 432 (58.2%) prematures. N.s. was diagnosed in 185 (43%) of cases. Neonates comprised 1) those admitted to NICU at the age of 1 or 2 days, who did not show clinical and microbiological symptoms of sepsis, they developed sepsis in the course of treatment and tested positive for the presence of bacteria or in blood, 2) preterms at the age of 5 or more days, born without infection and stayed at other hospital prior to admission to the NICU. They showed clinical symptoms of sepsis and had positive blood cultures. ELBW in 20%, VLBW in 62%, GA < 28 weeks in 28%, IUGR in 12%, severe birth asphyxia in 29% were noted. Mother of septic prematures had abnormal course of pregnancy in 78% and in 75% complications of delivery.
Results GBS colonization was detected in 53 (6.4%) of 827 newborns. Colonization in earth canal was found in 15 (28.3%) of them, in the throat — 9 (17%) and both were recorded in 29 (54.7%) of the newborns studied. The most common serotypes were III (37.7%), Ia (32%), V (9.4%), IV (5.7%), II (5.7%), Ib (3.7%), VI (2.1%) and unidentified (3.7%) All isolates were susceptible to penicillin whereas 3.8% showed resistance to erythromycin. The overall maternal colonization and vertical transmission rates were 15.3% and 28.4%, respectively. Conclusions Neonatal GBS colonisation was estimated similar to those reported from other industrialized countries. The most frequent serotypes identified are III and Ia. Intrapartum antibiotic prophylaxis has been shown to be effective in reducing the incidence GBS colonization in newborns. Standardized strategy for the prevention of early onset GBS disease in the newborn is necessary in Lithuania. doi:10.1016/j.earlhumdev.2008.09.173
Results Clinical symptoms of n.s. included pneumonia (95%), hepatomegaly (82%), gastrointestinal disorders (79%), shock (70%), DIC (32%), meningitis (30%), and pyuria (12%). Abnormal laboratory findings as metabolic acidosis (84%), increase of CRP (89%), WBC > 20.0G/l (46%), leukopenia 4.0 G/l (9%), trombocytopenia (52%), stab cells > 5% (40%), hyperbilirubinemia (15%), and glycemia disorders (20%) were noted. The dominating types of bacteria from the blood were Klebsiella pn. (61), Staph. epid. MR (49) and Pseudomonas aer. (27). Other MR staphylococcal strains (15), S. aureus (8), Streptococcus foecalis (8), Serratia marcescens (7), Enterobacter (6), Acinetobacter baumanii (4) were stated in 26% of n.s. prematures. More than 80% of preterms were intubated before they developed n.s., 94% received TPN, 26% were operated because of congenital defects. Mortality rate was 19.4% (36 cases), a significant
Abstract UENPS.158 Nosocomial Staphylococcus aureus fulminant sepsis in a neonatal intensive care: Absence of clonal spread Elsa Paulino⁎,a, Rosalina Barrosoa, Maria Miragaiab, Maria João Britoa, Luisa Sanchoa, Teresa Conceiçãob, Marta Aires-de-Sousac, Teresa Sardinhaa, Helena Carreiroa, Herminia Lencastred a Fernando Fonseca Hospital, Amadora, Portugal b Instituto de Tecnologia Quimica e Biológica (ITQB), Oeiras, Portugal c Escola Superior da saúde da Cruz vermelha Portuguesa, Lisboa, Portugal d Rockefeller University, New York, United States
S68
Abstracts
Background and aim Staphylococcus aureus (SA) is a well-known nosocomial pathogen among patients in neonatal intensive care units (NICUs) and is associated with substantial morbidity and mortality. Methicillin-susceptible S. aureus (MSSA) is frequently endemic, but there are reports of clusters of epidemics of disease among hospitalized neonates, both in well-baby nurseries and in NICUs. Materials and methods Retrospective review of clinical file of three patients died with SA infection in a period of a week in the NICU as well as records of active surveillance was performed. The MSSA isolates were characterized by pulsed-field gel electrophoresis (PFGE), and presence of virulence determinants was detected by multiplex PCR. Results In 2005, and within the period of a week three patients were septic with MSSA. The three babies were premature with extremely low birth weight (<1000 g). Two were twins and had late onset sepsis but no major risk factors. The other baby had early onset sepsis (second day of life) and the possible risks were umbilical venous catheter and mechanical ventilation. In all cases the disease was abrupt, and two of them showed signs of necrotizing enterocolitis, disseminated intravascular coagulation, evolution to septic shock and death within 15 to 48 h. One of the twins has a more extended disease with multi organic failure and death in a week. Blood cultures were positive for MSSA in two of the babies only. The isolates were identical by PFGE and positive for the LukE–LukD, gamahemolysin variant, beta-hemolysin and SEL toxic determinants. Active surveillance for SA was performed by culturing the anterior nares of parents and health care workers (HCW) as well as the environment of the NICU, but no identical isolates were found. The outbreak was controlled by enhanced infection control measures.
women (vagina and the rectum swabs). There were 250 GBS positive mothers, which delivered 253 newborns and received (199 women) or not received (51 women) the intrapartum antibiotic prophylaxis (IAP) according to CDC protocol. In 183 cases penicillin was used, in 16 cases it was macrolid. Selected parameters were examined retrospectively and statistically analysed. Results The frequency of the colonization with GBS was 11.4%. In 33 neonates (13%), the intrauterine infection of various etiology and localization was diagnosed. Two children (0.8%) were infected with GBS. The frequency of intrauterine infections in neonates whose mothers received IAP (22/199 cases), was statistically significantly lower than the frequency of infections in newborns whose mothers were not selected for it (11/51 cases), p = 0.036. In the group receiving penicillin statistically significantly lower frequency of intrauterine infection was observed, compared with the group receiving macrolid (8.2% v. 37.5%), p = 0.001. In 99 neonates, ear swab was performed. Positive results were obtained in 17 cases (18%). In 4/17 of positive results, the intrauterine infection occurred. Statistically significant differences between the frequency of the intrauterine infection in the groups of neonates colonized and not colonized with pathogens were not shown. Conclusions 1. 2.
3.
Perinatal prophylaxis against GBS does not completely eliminate infection in neonates. Intrapartum antibiotic prophylaxis is not related to a higher risk of the intrauterine infection of another etiology. Penicillin is a better choice than macrolid. Ear swab does not seem to be of diagnostic value for the neonates of GBS positive mothers.
doi:10.1016/j.earlhumdev.2008.09.175 Conclusions The molecular methods used showed that the strains isolated from the babies, carriers and environment belonged to different clones. Therefore it was not possible to determine the routes of transmission of the strains that caused the three infection episodes. Prompt recognition of the risk of spread within the NICU led to prevention of occurrence of new cases, showing that the implementation of enhanced infection control measures can be effective even in high risk units such as NICUs. doi:10.1016/j.earlhumdev.2008.09.174
Abstract UENPS.160 Abscessus caused by methicillin resistant Staphylococcus aureus in newborns Burbuqe Mustafa-Skenderi⁎, Shala Muje, Shaqiri Florim, Mimoza Alishani Q.K.U.K, Prishtine, Yugoslavia Background and aim Infections with MRSA, in recent time show increased tendency in NICU. Materials and methods
Abstract UENPS.159 Perinatal prophylaxis of group B streptococcal infections — The own experiences Bozena Kociszewska-Najman⁎,a, Anna Oslislob Medical University of Warsaw, Warsaw, Poland b The Higher School of Applied Sciences, Ruda Slaska, Poland
Our objective has been to analyze abscesses of skin and soft tissues at patients hospitalized in NICU in time period 2006–2008, symptomatology, laboratory changes, and therapy. Results
a
In many countries, including Poland, maternal group B streptococcal (GBS) screening program is not implemented. In the Obstetrics and Gynecology Clinic I of the Medical University of Warsaw, in accordance with recommendations of the Centers for Disease Control and Prevention (CDC), prophylaxis strategy has been performed since 01.01.2007. The aim of the study was to evaluate chosen procedures for the mother and the newborn based on the analysis of a type and frequency of intrauterine infection in the neonates of GBS positive mothers.
10 cases have been filed, with abscesses of skin and soft tissues from a total of 900 hospitalized, 5 of them were female and 5 were male, birth weight from 2050 g–3400 g. 2 of them have been premature, average 11 days. Most often localized part has been breast — 5 cases, 1 in thoracic part 2 in gluteal part of body, one in calcaneal part and the other one in parotid glandule. In all cases an incision and drainage of abscess has been made, in microbiological analysis of pus MRSA has been isolated, sensitive to Vankomycine. The rate of PCR has been from 36–96. WBC 6–40; 3 cases has been with hypoalbuminaemia and anaemia, in 4 cases blood culture has been positive for MRSA, 1 case in Klebsiella spec, 1 in Citrobacter and 4 others were negative. Therapy has lasted for 2–3 weeks with Vankomycin, Amikacin, and Ceftriaxon. All hospitalized patients had left the hospital in a good health condition.
Materials and methods
Conclusions
The studied population included 2212 pregnant patients hospitalized from 01.01.2007 to 17.04.2008. Bacterial culture was performed in all pregnant
Infections with MRSA are increasing in NICU, more often are in after first week of life, most often localised part was breast, in 60% it has been followed
Background and aim