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Objective:To investigate the serotype features of group B Streptococcus (GBS) vaginal colonization in late pregnancies and their relationship with early-onset neonatal GBS disease (GBS-EOD). Methods:Thirty-two strains were isolated from neonates delivered by GBS-positive mothers and hospitalized for GBS-EOD in Xiamen Maternal and Child Care Hospital from June 2016 to June 2018. Another 266 strains were isolated from vaginal samples from randomly selected late pregnant women who received antenatal screening and delivered in the same hospital during the same period with an allocation ratio of 12∶1. A total of 298 strains from mothers and 32 strains from neonates were involved. Every isolate was serotyped with latex agglutination assay. GBS infection caused by eleven serotypes and the correlation between GBS serotypes in late pregnant women and neonatal GBS-EOD were analyzed. Qualitative variables were compared using Chi-square or Fisher's exact test. A correlation analysis was presented by the column contact number C. Multiple analysis of multiple sample rates was performed with Post hoc testing. Differences between groups were analyzed according to the adjusted standardized residual. Results:A total of nine serotypes were identified among the 298 strains isolated from the mothers. The most prevalent serotype wasⅢ [55.0% (164/298)], followed byⅠb [16.4% (49/298)], Ⅰa [11.1% (33/298)], Ⅴ [9.4% (28/298)], Ⅱ [5.0% (15/298)], non-typable [NT, 1.0% (3/298)], and Ⅵ, Ⅷ and Ⅸ [0.7% (2/298) in each]. Neither Ⅳ nor Ⅶ serotype was identified. The 32 strains isolated from neonates with GBS-EOD belonged to five serotypes, which were Ⅲ [18/32 (56.3%)], Ⅰa [8/32 (25.0%)], Ⅰb [3/32 (9.4%)], Ⅱ [2/32 (6.2%)] and Ⅴ [1/32 (3.1%)]. The positive rates of GBS Ⅲ serotype in neonates with pneumonia, sepsis, and meningitis were 6/13, 7/14, and 5/5. However, no statistically significant difference was observed in the distribution of the five serotypes in GBS-EOD neonates ( P=0.654). Thirty neonates (93.7%) were cured, while two (6.3%) died. There were statistically significant differences among neonatal GBS-EOD caused by vertical transmission with Ⅰa, Ⅰb, Ⅱ, Ⅲ and Ⅴ, Ⅵ, Ⅷ, Ⅸ and NT serotypes ( P=0.046, contingency coefficient: 0.183). Further analysis showed that the adjusted absolute value of the standardized residual of serotype Ⅰa was 2.7 (>2), and the difference was statistically significant. However, the adjusted absolute value of the standardized residual of serotype Ⅲ was only 0.1, which was not statistically significant. Conclusions:Serotype Ⅲ is the most prevalent GBS serotype in late pregnant women and GBS-EOD neonates, and also the predominant serotype in infants with early-onset meningitis. Serotype Ⅰa could be highly vertically transmitted, while the virulence of serotypes Ⅲ and Ⅰa strains of GBS are the strongest.
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Objective To study the clinical manifestations and antibiotic sensitivity features of early-and late-onset invasive infections caused by group B Streptococcus (GBS). Methods A total of 96 infants with invasive GBS infections were enrolled prospectively from seven tertiary hospitals of GBS Infection Research Cooperative Group in southwest Fujian, such as Xiamen Maternal and Child Care Hospital, etc., from January 2016 to June 2018. According to the onset time of infection after birth, they were divided into early-onset GBS disease (GBS-EOD) group (<7 d, n=67) and the late-onset GBS disease (GBS-LOD) group (7-89 d, n=29). Clinical manifestations, disease spectrum, complications and outcomes of the two groups were compared. Drug sensitivity test was carried out using disk diffusion test. Chi-square or Fisher's exact test, two independent sample t-test or Mann-Whitney U tests were used for statistical analysis. Results (1) The average ages at onset in GBS-EOD and GBS-LOD groups were (15.8±6.7) h (0.5-142.0 h) and (25.0±8.1) d (9-89 d), respectively. The incidence of tachypnea, pallor, fever and convulsion were noted in 68.7% (46/67) vs 44.8% (13/29), 52.2% (35/67) vs 17.2% (5/29), 23.9% (16/67) vs 65.5% (19/29) and 7.5% (5/67) vs 48.3% (14/29) of GBS-EOD and GBS-LOD groups with χ2 values of 6.282, 10.199, 15.146 and 21.237 (all P<0.05). The main clinical manifestations of GBS-EOD were tachypnea and pallor, while most of the patients in the GBS-LOD group developed fever and convulsions. (2) The incidence of pneumonia, sepsis, meningitis, sepsis complicated by septic joints, pneumonia complicated by sepsis, sepsis complicated by meningitis and pneumonia complicated by sepsis and meningitis were noted in 43.3% (29/67) vs 20.7% (6/29), 9.0% (6/67) vs 17.2% (5/29), 0.0% (0/67) vs 3.4% (1/29), 0.0% (0/67) vs 6.9% (2/29), 31.3% (21/67) vs 13.8% (4/29), 6.0% (4/67) vs 31.0% (9/29) and 10.4% (7/67) vs 6.9% (2/29) of GBS-EOD and GBS-LOD groups. There was a statistically significant difference in the disease spectrum between the two groups (Fisher's exact test, all P<0.001). Compared with the GBS-LOD group, the GBS-EOD group had a higher incidence of pneumonia [85.1% (57/67) vs 41.4% (12/29), χ2=19.116, P<0.001] and a lower incidence of meningitis [16.4% (11/67) vs 41.4% (12/29), χ2=6.922, P=0.009]. Complications such as acute respiratory distress syndrome (ARDS), pulmonary hemorrhage, shock and persistent pulmonary hypertension of the newborn (PPHN) occurred much more in the GBS-EOD group than the GBS-LOD group [28.4% (19/67) vs 6.9% (2/29), 13.4% (9/67) vs 0.0% (0/29), 11.9% (8/67) vs 10.3% (3/29), 4.5% (3/67) vs 0.0% (0/29), χ2=13.683, P<0.001]. (3) Among the 96 patients, 23 (24.0%) had meningitis and 73 (76.0%) developed pneumonia and sepsis. Meningitis resulted in a higher fatality rate [17.4% (4/23) vs 4.1% (3/73), χ2=4.564, P=0.035] and longer average hospital stay [(37.2±12.6) vs (14.1±5.3) d, t=7.831, P<0.001] than pneumonia and sepsis. Seven out of the 19 meningitis survivors developed intracranial complications. (4) The overall fatality rate in this study was 7.3% (7/96) and no significant difference was found between GBS-EOD and GBS-LOD group [7.5% (5/67) vs 6.9% (2/29), χ2=0.010, P=0.982]. Among the 67 GBS-EOD infants, 58 (86.6%) occurred within 24 h and five of them died, but no death was reported in the other nine cases occurred after 24 h. (5) Totally 96 strains of GBS were isolated with 100% sensitivity to penicillin, ampicillin, cefazolin and meropenem, and 97% to vancomycin. Around 79.3%-91.0% of GBS isolates were resistant to clindamycin and erythromycin. Conclusions Clinial features vary greatly in GBS-LOD and GBS-EOD cases. Infants with meningitis have poor prognosis. The drug resistance rate of GBS to erythromycin and clindamycin are relatively high.
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Objective@#To analyze clinical features, treatment, prognosis and risk factors for death of capillary leak syndrome (CLS) in neonates.@*Methods@#This retrospective study involved 68 neonates with CLS treated in the Department of Neonatology, Women and Children's Hospital, School of Medicine, Xiamen University from January 2013 to December 2017. Clinical data, including features, causes, treatment and outcomes of those CLS cases were analyzed. Chi-square test and multivariate logistic regression analysis were performed.@*Results@#Among the 68 cases consisting of 49 males and 19 females, 86.7% (59/68) were born at ≥ 35 gestational weeks. Fifty-three neonates (77.9%) developed symptoms within three days after admission. Forty-two cases (61.8%) had respiratory distress syndrome and 35 (51.5%) had septicemia. The mortality rate was 23.5% (16/68). Among the survivors, 38.5% (20/52) showed abnormal cranial MRI. Univariate analysis with Chi-square test showed that neonatal death due to CLS was associated with the lactic acid level >10 mmol/L, oliguria lasting for 12 h or anuria for 8 h, no negative fluid balance occured within seven days, adrenaline infusion >0.6 μg/(kg·min) and administration of 3% sodium chloride. Multivariate logistic regression analysis showed that lactic acid level, oliguria/anuria duration and the time achieve negative fluid balance were independent risk factors for neonatal death of CLS.@*Conclusions@#Neonatal CLS is a condition with high fatality rate and poor prognosis. Respiratory distress syndrome and septicemia are the common causes. The prognosis of CLS might be improved by treatment with 3% sodium chloride. Lactic acid level, oliguria/anuria duration and the time achieve negative fluid balance are independent risk factors for neonatal death due to CLS.
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Group B Streptococcus (GBS) is an important pathogen which may result in miscarriage, intrauterine infection and puerperal infection. Neonatal GBS infection may lead to septicemia, pneumonia and meningitis. GBS can be divided into a variety of serotypes according to the antigenic structure of capsular polysaccharide, and different serotypes of GBS vary in ethnicity, geographical distribution, pathogen virulence and pathogenic species. The distribution and identification of GBS serotypes, and their relationships with genotypes, drug resistance, virulence factors and vaccine preparation of GBS were reviewed.
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ObjectiveTo investigate the incidence and pathogen distribution of neonatal early-onset sepsis (EOS) following exposure to antenatal antibiotics.MethodsOne hundred and eighty-four neonates who were admitted to Maternal and Child Care Hospital of Xiamen and identified as having EOS from January 2010 to December 2015 were enrolled. The clinical data were retrospectively analyzed. According to antenatal antibiotic exposure time, the infants were divided into the antibiotics group (≥4 hours) and the control group (0.05). Compared with the no-screening group, the positive rate of GBS decreased [7.6% (5/66) vs 18.6% (22/118)] and the positive rate of fungal infection increased [7.6%(5/66) vs 1.7% (2/118)] in the screening group (χ2=4.141,P=0.042;χ2=4.000,P=0.046). The distribution of other pathogenic bacteria such as coagulase-negativeStaphylococci andE. coli was not significantly different between the two groups (P>0.05, respectively). Drug resistance rates ofStaphylococcus (Staphylococcus aureus and coagulase-negativeStaphylococcus) to oxacillin and piperacillin-sulbactam were higher in the screening group than in the no-screening group [82.6% (19/23) vs 52.9% (18/34),χ2=5.302; 78.3% (18/23) vs 47.1% (16/34),χ2=5.549; bothP<0.05], and no vancomycin resistant bacterial strains were found.ConclusionsAntenatal antibiotic exposure may be effective in reducing the occurrence of prematurity, asphyxia,and GBS infection, but it increases the rate of fungal infection, and is not effective in reducing the incidence of complications and mortality or in changing the distribution of the other pathogens in EOS. Rational indications and timing of antenatal antibiotic exposure should be taken into consideration to reduce drug resistance.
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Objective To evaluate the value of procalcitonin(PCT)in different periods for diagno-sis of early-onset of neonatal bacterial infection.Methods One hundred and ninety-five newborns with intra-uterine infection risk factors were divided into two groups:infection group(24cases)and non-infection group(171cases).The levels of PCT,C-reactive protein(CRP)and WBC were measured in 2hours,6to 12hours,12to 36hours and more than 48hours after birth.The sensitivity and specificity of PCT in different periods in the diagnosis of early-onset infection were analyzed.Results There were no significant differ-ences in the positive rate of PCT,CRP and WBC in infection group in 2hours after birth(P﹥0.05).The sensitivity and specificity for diagnosis of early-onset infection of PCT were 91.7% and 86.5% at 6to 12hours after birth,which were higher than those of CRP and WBC.After birth in 12to 36hours was the physiologic peak of PCT,so it couldn′t have higher sensitivity and specificity.According to threshold of 0.5ng/ml,2ng/ml,and 10ng/ml for PCT,the sensitivity was 100%,91.7% and 100% respectively,and the specificity was 5.8%,53.8%and 95.9%respectively.Conclusion PCT in 6to12hours after birth,ac-cording to threshold of 2ng/ml,can reach higher sensitivity and specificity for diagnosis of early-onset neo-natal bacterial infection.
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Objective To investigate the effect of EDTA combined with ciprofloxacin on Pseudomonas aeruginose biofilm in vivo.Methods Pseudomonas aeruginosa was inhaled into the lung of guinea pigs and colonized,formed biofilm.After 7 days,the model was treated with ciprofloxacin,EDTA alone,or a combination of both for 7 days.The number of colony in the lungs is measured by agar plate.The pathological change of the lung is observed by hematoxylin and eosin (HE) staining and scanning electron microscope.Results EDTA combined with ciprofloxacin make the number of bacteria in the lungs reduced from l05 CFU/g to 10 CFU/g(t =24.67,P＜0.05),the lung lesion was less-sever histophathologically.Conclusion The combination of EDTA with ciprofloxacin has significant activity to remove mucoid PA biofilm in vivo.