Neonatal septicaemia

Antibiotic regimens for early-onset neonatal sepsis

BACKGROUND

Neonatal sepsis is a major cause of morbidity and mortality. It is the third leading cause of neonatal mortality globally constituting 13% of overall neonatal mortality. Despite the high burden of neonatal sepsis, high-quality evidence in diagnosis and treatment is scarce. Possibly due to the diagnostic challenges of sepsis and the relative immunosuppression of the newborn, many neonates receive antibiotics for suspected sepsis. Antibiotics have become the most used therapeutics in neonatal intensive care units. The last Cochrane Review was updated in 2004. Given the clinical importance, an updated systematic review assessing the effects of different antibiotic regimens for early-onset neonatal sepsis is needed.

OBJECTIVES

To assess the beneficial and harmful effects of different antibiotic regimens for early-onset neonatal sepsis.

SEARCH METHODS

We searched the following electronic databases: CENTRAL (2020, Issue 8); Ovid MEDLINE; Embase Ovid; CINAHL; LILACS; Science Citation Index EXPANDED and Conference Proceedings Citation Index - Science on 12 March 2021. We searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs.

SELECTION CRITERIA

We included RCTs comparing different antibiotic regimens for early-onset neonatal sepsis. We included participants from birth to 72 hours of life at randomisation.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias. We used the GRADE approach to assess the certainty of evidence. Our primary outcome was all-cause mortality, and our secondary outcomes were: serious adverse events, respiratory support, circulatory support, nephrotoxicity, neurological developmental impairment, necrotising enterocolitis, and ototoxicity. Our primary time point of interest was at maximum follow-up.

MAIN RESULTS

We included five RCTs (865 participants). All trials were at high risk of bias. The certainty of the evidence according to GRADE was very low. The included trials assessed five different comparisons of antibiotics. We did not conduct any meta-analyses due to lack of relevant data. Of the five included trials one trial compared ampicillin plus gentamicin with benzylpenicillin plus gentamicin; one trial compared piperacillin plus tazobactam with amikacin; one trial compared ticarcillin plus clavulanic acid with piperacillin plus gentamicin; one trial compared piperacillin with ampicillin plus amikacin; and one trial compared ceftazidime with benzylpenicillin plus gentamicin. None of the five comparisons found any evidence of a difference when assessing all-cause mortality, serious adverse events, circulatory support, nephrotoxicity, neurological developmental impairment, or necrotising enterocolitis; however, none of the trials were near an information size that could contribute significantly to the evidence of the comparative benefits and risks of any particular antibiotic regimen. None of the trials assessed respiratory support or ototoxicity. The benefits and harms of different antibiotic regimens remain unclear due to the lack of well-powered trials and the high risk of systematic errors.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to support any antibiotic regimen being superior to another. Large RCTs assessing different antibiotic regimens in early-onset neonatal sepsis with low risk of bias are warranted.

Antibiotic regimens for late-onset neonatal sepsis

BACKGROUND

Neonatal sepsis is a major cause of morbidity and mortality. It is the third leading cause of neonatal mortality globally constituting 13% of overall neonatal mortality. Despite the high burden of neonatal sepsis, high-quality evidence in diagnosis and treatment is scarce. Due to the diagnostic challenges of sepsis and the relative immunosuppression of the newborn, many neonates receive antibiotics for suspected sepsis. Antibiotics have become the most used therapeutics in neonatal intensive care units, and observational studies in high-income countries suggest that 83% to 94% of newborns treated with antibiotics for suspected sepsis have negative blood cultures. The last Cochrane Review was updated in 2005. There is a need for an updated systematic review assessing the effects of different antibiotic regimens for late-onset neonatal sepsis.

OBJECTIVES

To assess the beneficial and harmful effects of different antibiotic regimens for late-onset neonatal sepsis.

SEARCH METHODS

We searched the following electronic databases: CENTRAL (2021, Issue 3); Ovid MEDLINE; Embase Ovid; CINAHL; LILACS; Science Citation Index EXPANDED and Conference Proceedings Citation Index - Science on 12 March 2021. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-RCTs.

SELECTION CRITERIA

We included RCTs comparing different antibiotic regimens for late-onset neonatal sepsis. We included participants older than 72 hours of life at randomisation, suspected or diagnosed with neonatal sepsis, meningitis, osteomyelitis, endocarditis, or necrotising enterocolitis. We excluded trials that assessed treatment of fungal infections.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias. We used the GRADE approach to assess the certainty of evidence. Our primary outcome was all-cause mortality, and our secondary outcomes were: serious adverse events, respiratory support, circulatory support, nephrotoxicity, neurological developmental impairment, necrotising enterocolitis, and ototoxicity. Our primary time point of interest was at maximum follow-up.

MAIN RESULTS

We included five RCTs (580 participants). All trials were at high risk of bias, and had very low-certainty evidence. The five included trials assessed five different comparisons of antibiotics. We did not conduct a meta-analysis due to lack of relevant data. Of the five included trials one trial compared cefazolin plus amikacin with vancomycin plus amikacin; one trial compared ticarcillin plus clavulanic acid with flucloxacillin plus gentamicin; one trial compared cloxacillin plus amikacin with cefotaxime plus gentamicin; one trial compared meropenem with standard care (ampicillin plus gentamicin or cefotaxime plus gentamicin); and one trial compared vancomycin plus gentamicin with vancomycin plus aztreonam. None of the five comparisons found any evidence of a difference when assessing all-cause mortality, serious adverse events, circulatory support, nephrotoxicity, neurological developmental impairment, or necrotising enterocolitis; however, none of the trials were near an information size that could contribute significantly to the evidence of the comparative benefits and risks of any particular antibiotic regimen. None of the trials assessed respiratory support or ototoxicity. The benefits and harms of different antibiotic regimens remain unclear due to the lack of well-powered trials and the high risk of systematic errors.

AUTHORS' CONCLUSIONS

Current evidence is insufficient to support any antibiotic regimen being superior to another. RCTs assessing different antibiotic regimens in late-onset neonatal sepsis with low risks of bias are warranted.

Study of Antibiotic Susceptibility among Bacterial Isolates in Neonatal Intensive Care Unit of a Tertiary Care Hospital: A Descriptive Cross-sectional Study

Introduction:

Neonatal sepsis is a major cause of neonatal morbidity and mortality worldwide, especially in developing countries like Nepal. Antibiotic resistance among microorganisms poses new challenges in the treatment of neonatal sepsis. The present study is conducted with the objectives of determining clinico-bacteriological profile and antibiotic susceptibility among isolated bacteria in a neonatal intensive care unit.

Methods:

A descriptive cross-sectional study was conducted from January 1, 2017, to December 31, 2019, in the neonatal intensive care unit of a tertiary care hospital after obtaining ethical clearance from Institutional Review Committee (Ref: 2020-064). The sample size was calculated and 77 neonates with culture-proven sepsis were included in the study. The antibiotic susceptibility tests of the isolates were done by Kirby-Bauer disc diffusion method. Data entry was done in Statistical Packages for the Social Sciences version 20.

Results:

Of the 841 specimens (blood, cerebrospinal fluid, urine, tracheal aspirate and pus) processed for culture, bacteria were isolated in 84 (10.0%) specimens. Among the 84, gram-negative bacilli were the predominant isolates 76 (90.5%); of which Acinetobacter baumannii was the most common 27 (32.1%). Both the Gram-negative and the Gram-positive bacteria showed high resistance to Penicillin and Cephalosporins. Gram-negative bacteria showed maximum sensitivity to Colistin, Carbapenems, Tigecycline and Fluoroquinolones. Gram-positive bacteria showed maximum susceptibility to Amikacin, Vancomycin and Carbapenems.

Conclusions:

Judicious use of antibiotics based on the updated knowledge of prevalent organisms in the local hospital setting and their antibiotic sensitivity pattern is of utmost importance for the effective treatment of neonatal sepsis.

Antibiotic regimens for neonatal sepsis - a protocol for a systematic review with meta-analysis

BACKGROUND

Sepsis is a major cause of morbidity and mortality among neonates and infants. Antibiotics are a central part of the first line treatment for sepsis in neonatal intensive care units worldwide. However, the evidence on the clinical effects of the commonly used antibiotic regimens for sepsis in neonates remains scarce. This systematic review aims to assess the efficacy and harms of antibiotic regimens for neonatal sepsis.

METHODS

Electronic searches will be conducted in MEDLINE, Embase, The Cochrane Library, CINAHL, ZETOC and clinical trial registries (clinicaltrials.gov and ISRCTN). We will include randomised controlled trials of different antibiotic regimens for sepsis of neonates and infants. Eligible interventions will be any antibiotic regimen. Two reviewers will independently screen, select, and extract data. The methodological quality of individual studies will be appraised following Cochrane methodology. Primary outcomes will be 'all-cause mortality' and 'serious adverse events'. Secondary outcomes will be 'need for respiratory support', 'need for circulatory support', 'neurodevelopmental impairment', ototoxicity, nephrotoxicity and necrotizing enterocolitis. We plan to perform a meta-analysis with trial sequential analysis.

DISCUSSION

This is the study protocol for a systematic review on the effects of different antibiotic regimens for neonatal sepsis. The results of this systematic review intent to adequately inform stakeholders or health care professionals in the field of neonatal sepsis, and to aid appropriate development of treatment guidelines.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO reference number: CRD42019134300.

Network-based analysis of diagnosis progression patterns using claims data

In recent years, several network models have been introduced to elucidate the relationships between diseases. However, important risk factors that contribute to many human diseases, such as age, gender and prior diagnoses, have not been considered in most networks. Here, we construct a diagnosis progression network of human diseases using large-scale claims data and analyze the associations between diagnoses. Our network is a scale-free network, which means that a small number of diagnoses share a large number of links, while most diagnoses show limited associations. Moreover, we provide strong evidence that gender, age and disease class are major factors in determining the structure of the disease network. Practically, our network represents a methodology not only for identifying new connectivity that is not found in genome-based disease networks but also for estimating directionality, strength, and progression time to transition between diseases considering gender, age and incidence. Thus, our network provides a guide for investigators for future research and contributes to achieving precision medicine.

Factors which affect mortality in neonatal sepsis

AIM

Neonatal sepsis is an important cause of mortality and morbidity in newborns. The causative agents may be different in different units and may change in time. It was aimed to examine the microbiological agents leading to sepsis, clinical features and antibiotic resistances in babies with sepsis hospitalized in our unit in a two-year period.

MATERIAL AND METHODS

The clinical features, microbiological and laboratory results, antibiotic resistance patterns and mortality rates of the newborns with sepsis followed up in our unit between 2010 and 2011 were examined in the patient record system.

RESULTS

351 babies diagnosed with sepsis among 3219 patients hospitalized in the neonatal intensive care unit were included in the study. The mean gestational age was found to be 30.1±4.1 weeks, the mean birth weight was found to be 1417.4±759.1 g and the mean hospitalization time was found to be 43.6±34.4 days. Blood cultures were found to be positive in 167 (47.6%) patients, urine cultures were found to be positive in 6 (7.1%) patients and cerebrospinal fluid cultures were found to be positive in 34 (9.6%) cases. Candida grew in 5 patients (2 patients with early-onset sepsis and 3 patients with late-onset sepsis). The most common cause of sepsis was found to be staphylococci (coagulase negative staphylococcus was found in 65 patients (51%) and Staphylococcus aureus was found in 38 patients (39%). 49.6% (n=63) of the gram positive bacteriae and 60% (n=21) of the gram negative bacteriae were resistant to antibiotics. Six (7.1%) of the patients who were infected with these bacteriae were lost. In total 24 babies were lost because of sepsis. The bacteriae which caused to mortality with the highest rate included E. coli, coagulase negative staphylocicci, S. aureus and Klebsiella. Low birth weight, mechanical ventilation and parenteral nutrition were found to be significant risk factors in terms of mortality.

CONCLUSIONS

Staphylococci were found to be the most common agents in neonatal sepsis. Low birth weight, mechanical ventilation and parenteral nutrition are significant risk factors in terms of mortality.

Disseminated, large-sized neonatal pneumatoceles: the wait-and-see strategy

Pulmonary pneumatoceles are thin-walled, air-filled cysts that develop within the lung parenchyma. Most often, they occur as a sequel of acute pneumonia, commonly caused by Staphylococcus aureus in children. Limited data are available about infective pulmonary cysts in newborns. We report a case of a newborn, who developed multiple pneumatoceles after Escherichia coli pneumonia.

Cardiopulmonary morbidity of streptococcal infections in a PICU

AIM

The streptococci are important bacteria that cause serious childhood infections. We investigated cardiopulmonary morbidity associated with streptococcal infection and pediatric intensive care unit (PICU) admission.

METHODS

A retrospective study between 2002 and 2013 of all children with a laboratory isolation of streptococcus.

RESULTS

There were 40 (2.3%) PICU patients with streptococcal isolations including Streptococcus pyogenes (Group A streptococcus, GAS, n = 7), Streptococcus agalactiae (Group B streptococcus, GBS, n = 5), Streptococcus pneumoniae (SP, n = 20), alpha-hemolytic (n = 4), beta-hemolytic (n = 2) and gama-hemolytic (n = 2) streptococci. Comparing among GAS, GBS and SP, respiratory isolates were more likely positive for GAS or SP (P = 0.033), whereas cerebrospinal fluid was more likely positive for GBS (P = 0.002). All GAS and GBS, and the majority of SP (90%) were sensitive to penicillin. All SP specimens were sensitive to cefotaxime and vancomycin. These infections were associated with high PICU mortality of 43%, 20% and 25%, respectively. Isolation of streptococci was associated with a 30% mortality and high rates of need for mechanical ventilatory and inotropic supports. Patients with GAS, SP or any streptococcal isolation had relative risks [95% confidence interval (CI), P value] of PICU deaths of 7.5 (CI 3.1-18.1, P < 0.0001), 4.5 (CI 2.0-9.8, P < 0.0002) and 5.7 (CI 3.4-9.5, P < 0.0001), respectively. In SP, older children had significantly higher prevalence of premorbid conditions such as malignancy, mental retardation/cerebral palsy ± seizure disorders, chromosomal or genetic disorders (P = 0.003) than children <5 years of age. Serotypes were available for some of these specimens that included 19A, 6B, 3 and 6C. There were four SP deaths with multiorgan system failure and hemolytic uremic syndrome (two 19A and two serotype 3).

CONCLUSIONS

Severe streptococcal infections are associated with significant morbidity and mortality despite treatment with systemic antibiotics and intensive care unit support. GAS and SP affect the lungs of children, whereas GBS more likely causes meningitis in infants. The expanded coverage of newer polyvalent pneumococcal vaccines can probably prevent infections by serotypes 19A, 19F, 6B and 3.

Neonatal bacterial septicaemia at the Mount Hope Women's Hospital, Trinidad

This retrospective study to determine the incidence of bacterial septicaemia in neonates at the Mount Hope Women's Hospital, Trinidad during a 2-year period, 1996 to 1997, included all neonates whose blood or cerebrospinal fluid cultured positive for bacteria. There were 9866 live births (LB), 102 of whom were diagnosed with bacterial sepsis, an incidence of 10/1000 LB. Thirty-one neonates had a positive culture for group B Streptococcus, an incidence of 3/1000 LB. Gram-negative organisms accounted for 63% of positive cultures. There were three outbreaks of nosocomial infection, two caused by Enterobacter spp with mortality rates of 37% and 50% and one outbreak caused by Pseudomonas aeruginosa with a mortality rate of 25%. The overall mortality rate was 27% (27/102), 63% were boys and 58% were preterm. The incidence of neonatal bacterial sepsis of 10/1000 LB is the highest recorded for the Caribbean and indicates that infection might be an important cause of the high perinatal mortality rate.

Neonatal group B streptococcal infection at the University Hospital of the West Indies, Jamaica: a 10-year experience

AIM

To describe the incidence, clinical presentation and outcome of neonatal group B streptococcal (GBS) infection at the University Hospital of the West Indies (UHWI).

METHODS

A 10-year retrospective review of all inborn neonates admitted to the neonatal unit of UHWI with GBS infection between 1 January 1991 and 31 December 2000 was conducted. Differences in maternal and neonatal characteristics between early- and late-onset disease (EOD, LOD) were determined.

RESULTS

There were 32,029 live births and 29 neonates were admitted for GBS infection, an incidence of 0.91/1000 live births (95% CI 0.58-1.23/1000). Twenty-one (72%) neonates had EOD, a rate of 0.66/1000 live births (95% CI 0.38-0.94/1000) and eight (28%) had LOD, a rate of 0.23/1000 (95% CI 0.08-0.42/1000). Seventeen of the 21 (81%) cases of EOD occurred within the 1st 24 hours of life. The most common clinical diagnosis was septicaemia (17, 61%), followed by pneumonia (8, 28%) and meningitis (3, 11%). All five (100%) babies whose mothers' membranes were ruptured for >18 hours had EOD. The babies of all six (100%) women with intrapartum pyrexia went on to have EOD. A greater proportion of babies (63%) with LOD were preterm and of low birthweight. The most common presenting symptom was respiratory distress which occurred more frequently in neonates with EOD, p=0.006. One neonate died, giving a case fatality rate of 3.6%.

CONCLUSION

Although the incidence of GBS infection is relatively low at UHWI, further reduction in the incidence might be achieved by implementation of measures to prevent perinatal transmission.

Trends in epidemiology of neonatal sepsis in a tertiary center in Korea: a 26-year longitudinal analysis, 1980-2005

There were many reports of longitudinal changes in the causative organisms of neonatal sepsis in Western countries but few in Asia. We aimed to study longitudinal trends in the epidemiology of neonatal sepsis at Seoul National University Children's Hospital (SNUCH), a tertiary center in Korea, and compared the results to previous studies of Western countries. The medical records of all of the neonates who were hospitalized at SNUCH from 1996 to 2005 with positive blood cultures were reviewed. We also compared the findings to previous 16-yr (1980-1995). One hundred and forty-nine organisms were identified in 147 episodes from 134 infants. In comparison with the previous 16-yr studies, there was a decrease in the number of Escherichia coli infections (16.2% vs 8.7%: odds ratio [OR] 0.495; 95% confidence interval [CI], 0.255-0.962; P = 0.035), but an increase in Staphylococcus aureus (16.6% vs 25.5%: OR 1.720; 95% CI, 1.043-2.839; P = 0.033) and fungal infections (3.3% vs 18.7%: OR 6.740; 95% CI, 2.981-15.239; P < 0.001), predominantly caused by Candida species. In conclusion, the incidence of sepsis caused by E. coli decreases, but S. aureus and fungal sepsis increases significantly. Compared with Western studies, the incidence of sepsis caused by S. aureus and fungus has remarkably increased.

Clinical microbiology of early-onset and late-onset neonatal sepsis, particularly among preterm babies

Prematurity has got special challenge for clinicians and also other medical staff, such as microbiologists. Immature host defense mechanisms support early-onset sepsis, which can be very serious with very high mortality. While the past decade has been marked by a significant decline in early-onset group B streptococcal (GBS) sepsis in both term and preterm neonates, the overall incidence of early-onset sepsis has not decreased in many centers, and several studies have found an increase in sepsis due to gram-negative organisms. With increasing survival of these more fastidious preterm infants, late-onset sepsis or specially nosocomial bloodstream infection (BSI) will continue to be a challenging complication that affects other morbidities, length of hospitalization, cost of care, and mortality rates. Especially the very low birthweight (VLBW) infants sensitive to serious systemic infection during their initial hospital stay. Sepsis caused by multiresistant organisms and Candida spp. are also increasing in incidence, has become the most common cause of death among preterm infants. This review focuses on the clinical microbiology of neonatal sepsis, particularly among preterm babies, summarizing the most frequent bacterial and fungal organisms causing perinatally acquired and also nosocomial sepsis.

Aetiology, risk factors and immediate outcome of bacteriologically confirmed neonatal septicaemia in Mulago hospital, Uganda

BACKGROUND

Neonatal septicaemia remains a major cause of morbidity and mortality. The aetiology, risk factors and outcome of this problem need to understood.

OBJECTIVE

To determine the aetiology, risk factors and immediate outcome of bacteriologically confirmed neonatal septicaemia in Mulago hospital.

METHODS

Blood cultures were aseptically obtained from neonates presenting with clinical sepsis by WHO criteria to Mulago during a five month period between July and November 2002. Blood was placed in Brain Heart Infusion media and incubated within 30 minutes. Subcultures were plated daily up to 7 days on blood, chocolate and MacConkey agar and incubated in aerobic and 5% carbon dioxide conditions. Pure colonies were identified by Gram stain and biochemical tests and antibiotic sensitivities were obtained.

RESULTS

Gram positive organisms were predominant (69.2%) followed by E. coli (17%) and Group B Streptococci (GBS) (7%). Staphylococcus aureus and E. coli dominated isolates in early and late onset sepsis. S. aureus was more sensitive to gentamicin than to cloxacillin. The sensitivity of E. coli to ceftriaxone was 94.1%. Factors significantly associated with neonatal septicaemia were male sex, history of convulsions, hypoglycaemia, lack of antenatal care, late onset sepsis and umbilical pus discharge. Mortality in sepsis cases was 18.1%, and 84% of deaths occurred in the first 2 days of admission. Hypoglycaemia was significantly associated with death (p < 0.01).

CONCLUSION

S. aureus predominates the aetiology of neonatal septicaemia followed by E.coli. Most deaths occur in the first 48 hours of admission and hypoglycaemia is significantly associated with death.

Serum IL-1beta, IL-6, IL-8, and TNF-alpha levels in early diagnosis and management of neonatal sepsis

Aim. To determine serum IL-1β, IL-6, IL-8, and TNF-α levels in neonatal sepsis at the time of diagnosis and after therapy, and to show the meaningful on the follow up. Methods. This prospective study was performed on newborns who were hospitalized for neonatal sepsis and who were classified as culture-proven sepsis (n=12), as culture-negative sepsis (n=21), and as healthy newborns (n=17). Results. At the time of diagnosis, serum IL-1β, IL-6, IL-8, and TNF-α levels of culture-proven sepsis were significantly higher than those of the control groups (P<.05). At the time of diagnosis, IL-1β, IL-6, IL-8, and TNF-α levels of culture-proven sepsis and culture-negative sepsis were significantly higher than levels at the seventh day after antibiotic treatment. Conclusion. Serum IL-1β, IL-6, IL-8, and TNF-α are mediators of inflammation and can be used at the diagnosis and at the evaluation of the therapeutic efficiency in neonatal sepsis.

Disinfection with 10% povidone-iodine versus 0.5% chlorhexidine gluconate in 70% isopropanol in the neonatal intensive care unit

AIM

The finding that 10% povidone-iodine skin disinfectant may compromise thyroid function in premature infants prompted its replacement with 0.5% chlorhexidine gluconate solution in 70% isopropanol. The objective of this study was to compare the incidence rates of true infection and contamination associated with the use of these two disinfectants in the neonatal intensive care unit.

METHODS

The study population comprised two cohorts of infants admitted to our neonatal intensive care unit: 1) in 1992-1993 when only 10% povidone-iodine was used as a skin disinfectant, and 2) in 1995-1996 when only 0.5% chlorhexidine gluconate solution in 70% isopropanol was used. A retrospective chart review was conducted to determine whether all documented positive blood, CSF and suprapubic aspirate cultures indicated true infection or contamination. True infection was defined as clinical symptoms and/or laboratory abnormalities suggestive of sepsis, with positive blood, CSF or suprapubic aspirate cultures.

RESULTS

1146 infants were admitted during the study periods, 507 during the first period and 639 during the second. In the early group, 17.6% of infants had major malformations, 72.0% were premature and 25.2% had weights of < 1500 g. Corresponding percentages for the latter group were 16.0%, 80.6% and 32.9%, respectively. No statistically significant differences were found between the two research periods in rate of infants with positive blood cultures, true infections, or contamination.

CONCLUSION

The use of 0.5% chlorhexidine gluconate solution in 70% isopropanol as a skin disinfectant is justified in neonatal intensive care units because it is not associated with an increased incidence of infections as opposed to 10% povidone-iodine and is devoid of detrimental effects.

Role of cytokines (interleukin-1beta, 6, 8, tumour necrosis factor-alpha, and soluble receptor of interleukin-2) and C-reactive protein in the diagnosis of neonatal sepsis

AIM

To investigate whether the serum levels of interleukin-1beta, 6, 8, tumour necrosis factor-alpha and the soluble receptor of IL-2 are useful in the diagnosis of neonatal sepsis, and whether their diagnostic power is increased when in combination with classical markers such as C-reactive protein and white blood cell count.

METHODS

Blood samples were collected at admission from 40 neonates with suspected infection. Patients were included in different groups according to the bacteriological and laboratory results: Group I consisted of 20 newborns with positive blood cultures and other biological tests suggestive of infection. Group II included 20 neonates with negative blood cultures and biological tests not suggestive of infection. The control group included 20 healthy neonates with no clinical or biological data of infection.

RESULTS

Mean values of C-reactive protein were significantly higher in Group I. No differences were found between the groups for white blood cell count, with the exception of the presence of leucocytosis in Group II. Levels of interleukin-1beta, 6, 8, tumour necrosis factor-alpha, soluble receptor of interleukin-2, and C-reactive protein were significantly higher in infected neonates than in the control groups. Detection sensitivity and specificity were 80 and 92% for C-reactive protein, 60 and 87% for interleukin-1beta, 61 and 80% for interleukin-6, 62 and 96% for interleukin-8, 54 and 92% for tumour necrosis factor-alpha and 63 and 94% for soluble receptor of interleukin-2. The discriminant analysis showed that the best combination for sepsis diagnosis was C-reactive protein + interleukin-8 + soluble receptor of interleukin-2, with a sensitivity of 85% and a specificity of 97.1%.

CONCLUSION

Our study suggests that no individual test can on its own identify infected neonates, and that although the combination of C-reactive protein, interleukin-8 and the soluble receptor of interleukin-2 exhibits a high specificity, its sensitivity is limited.

Invasive group B streptococcal infections in Sweden: incidence, predisposing factors and prognosis

OBJECTIVES

To study the incidence, clinical manifestations, concomitant conditions and case-fatality rate in patients with invasive group B Streptococcus (GBS) infections in the Göteborg area (mean population 582,666) of Sweden during 1981-95.

DESIGN

Patients were identified from the records of the Department of Clinical Bacteriology. Clinical data were obtained from hospital records.

RESULTS

GBS was isolated from blood, cerebrospinal fluid or other sterile body fluids from 211 patients with 215 infectious episodes; 108 in neonates, and 107 in non-neonates. The incidence was 2.4/100,000 per year, with the highest rates in neonates and in persons 65 years old or older. The incidence in neonates was 0.92/1,000 live births. The most common manifestation was septicemia with unknown focus. Of the neonates, 54% were full term and had no underlying conditions. Of the non-neonates, 15% had no underlying conditions. The most common underlying conditions were preterm delivery in neonates, and arteriosclerotic disease and diabetes mellitus in non-neonates. The case-fatality rates were 13% in neonates and 16% in non-neonates.

CONCLUSIONS

GBS is an important pathogen in neonates and in adults with concomitant conditions. The morbidity and mortality rates necessitate research to develop GBS vaccines both for women of fertile age and for patients with a wide variety of underlying diseases.

Neonatal bacteraemia: a population-based study

The aims of this study were to explore the incidence of neonatal bacteraemia and identify the risk factors among neonatal intensive care unit (NICU) patients. The study included 3339 neonates admitted to the NICU of Ioannina University Hospital, North-Western Greece, during the 10-y period 1989-98. Logistic regression was used to assess the contribution of different risk factors to bacteraemia. A diagnosis of bacteraemia was made in 90 neonates (2.7%), 10 of whom (11%) died. Gram-negative bacilli, coagulase-negative Staphylococci and Streptococci were the most common pathogens: 42%, 34% and 17%, respectively. Premature rupture of membranes was the main risk factor for early-onset sepsis (relative risk 6.28) and respiratory distress syndrome was the main risk factor for late-onset sepsis (relative risk 5.70). The relative size of neonates for their gestational age did not appear to influence the risk of infection. Case fatality was higher for early- than for late-onset sepsis (relative risk 6.59). In conclusion, certain conditions were confirmed to predispose patients to neonatal bacteraemia; neonatal morbidity and mortality can be reduced by intervening to control these predisposing factors.

No increase in rates of early-onset neonatal sepsis by non-group B Streptococcus or ampicillin-resistant organisms

OBJECTIVE

We assessed the impact of a risk-based approach to group B Streptococcus (GBS) prophylaxis on the rates of early-onset neonatal sepsis (EONS).

STUDY DESIGN

A retrospective cohort study of neonates born at a tertiary-care hospital from 1990 to 1996 was performed. Cases of EONS were identified among neonates born in a period without GBS prophylaxis (1990-1992) and compared with those born in a period with GBS prophylaxis (1993-1996). The antibiotic susceptibility data on each organism isolated in the blood culture were obtained.

RESULTS

In the period without prophylaxis, 99 cases of EONS were identified among 25,934 neonates for a rate of 3.8 per 1000 births. In the period with prophylaxis, 90 cases of EONS occurred among 34,262 neonates for a rate of 2.6 per 1000. The rate of GBS-EONS significantly decreased between the 2 periods (from 1.9 to 1.1, P =.01). There was a trend toward a decrease in the rate of EONS caused by non-GBS gram-positive organisms (from 1.2 to 0.7, P =.06). There was no significant increase in the rate of EONS caused by gram-negative or ampicillin-resistant organisms.

CONCLUSIONS

A risk-based approach to GBS prophylaxis reduced the incidence of GBS-EONS at a tertiary-care hospital. This decrease was not accompanied by an increase in the incidence of EONS by non-GBS or ampicillin-resistant organisms.

[Severe neonatal bacterial infections]

The prognosis of septicemic forms of early and late neonatal sepsis is severe with a high rate of mortality especially in premature infants. The evaluation of severity is difficult because of the non specificity of the clinical signs and mortality seems to be a good means of evaluation. A study was conducted in France on the mortality due to infection in neonatal intensive care units and neonatology wards during the third trimester 2000. Among 18 units, the mortality rate was 9.3% of admissions, corresponding to 11 early onset sepsis and 17 nosocomial infections. Death in primitive infections is essentially due to group B streptococci and E. coli with a more important risk in low gestational age infants. The nosocomial infections arise almost only in premature infant. Prognosis of infections due to Staphylococcus coagulase negative staphylococci, most frequent pathogens is good but mortalities rate is higher for enterobacteriacae--40% and for Pseudomonas, 62%.

Clinico-bacteriological study of neonatal septicemia in Hubli

Septicemia is a leading cause of neonatal morbidity and mortality in India. In a study of 242 infants with septicemia conducted between March 1996 & June 1997 at Hubli, Karnataka, 43.39% infants had 'very early onset' sepsis (VOS), 40.08%, had 'early onset' sepsis (EOS), and 16.53% 'late onset' sepsis (LOS). 54.55% neonates had birth weight below 2000 g and 39.67% were born before 37 weeks of gestation. The cardiorespiratory signs and jaundice were the most frequent clinical features. The blood culture positivity rate was 64.87%. Klebsiella species was the commonest causative pathogen found and multidrug resistance was frequent. The overall mortality rate was 47.52% and the case fatality rate in LOS was higher than in VOS and EOS (p < 0.001). The mortality was significantly higher in neonates with lower birth weight and lower gestational age (p < 0.001). The study underlines the importance of monitoring the various features of neonatal septicemia, as well as the drug resistance of the pathogens from the nurseries.

Umbilical vein interleukin 6 and tumor necrosis factor alpha plasma concentrations in the very preterm infant

OBJECTIVE

To examine the relationship between umbilical vein plasma concentrations of interleukin 6 (IL-6) and tumor necrosis factor (TNF)-alpha and early neonatal sepsis in the very preterm infant, and the histopathologic findings of chorioamnionitis in the placentas from these pregnancies.

METHODS

A prospective study was conducted in 43 very preterm, singleton infants delivered at or before 32 weeks of gestation. IL-6 and TNF-alpha were measured by enzyme-linked immunoassay. Placentas from these pregnancies were histologically examined for the presence of chorioamnionitis. Infants were prospectively classified as confirmed sepsis group, clinical sepsis group or control group. IL-6 and TNF-alpha plasma concentrations were not normally distributed, so they were transformed to their natural log values for statistical analysis.

RESULTS

The enrolled infants had a mean gestational age of 27.2 +/- 2.7 weeks and a mean birth weight of 956 +/- 325 g. Three (7%) infants had confirmed sepsis, 18 (42%) were in the clinical sepsis group and 22 (51%) were in the control group. IL-6 concentrations but not TNF-alpha were significantly higher (P < 0.05) in the confirmed (8.9 +/- 1.7) and clinical sepsis (5.5 +/- 2.4) groups in comparison with the control group (2.1 +/- 1.6). We examined 42 placentas. Twenty-three (55%) had no evidence of chorioamnionitis, 1 (2%) had mild grade, 8 (19%) had a moderate grade and 10 (24%) had a severe grade of chorioamnionitis. IL-6 was significantly elevated in the moderate (5.9 +/- 1.6 vs. 1.9 +/- 1.6) and severe grade (7.2 +/- 2.3 vs. 1.9 +/- 1.6) of chorioamnionitis, in the presence of acute deciduitis (6.0 +/- 2.7 vs. 2.1 +/-1.8), chorionic vasculitis (6.8 +/- 2.1 vs. 2.2 +/- 1.9) and funisitis (7.3 +/- 1.9 vs. 2.7 +/- 2.3) (P < 0.05) TNF-alpha plasma concentrations were not significantly different.

CONCLUSION

An elevated umbilical vein IL-6 concentration is a good indicator of sepsis syndrome in the very preterm infant and also correlates with histologic chorioamnionitis in these pregnancies.

Neonatal gram-negative bacteremia

A 22 months prospective study of neonatal gram-negative bacteremia was undertaken in a 15 bed NICU to find out the incidence and antibiotic resistance patterns. Clinically suspected 1326 cases of neonatal sepsis were studied during this period. More than 25% of the cases were microbiologically positive for sepsis. Among 230 (67.2%) cases of gram-negative bacteremia, the predominant isolates were Pseudomonas aeruginosa (38.3%), Klebsiella pneumoniae (30.4%), Escherichia coli (15.6%) and Acinetobacter sp. (7.8%). Fifty-nine per cent of the neonates were born in hospital while 41% were from community and referral cases. Lower respiratory tract infection, umbilical sepsis, central intravenous line infection and infection following invasive procedures were the most commonly identified sources of septicemia. Prematurity and low birth weight were the main underlying conditions in 60% of the neonates. Total mortality was 32%. Increased mortality was mainly associated with neutropenia, nosocomial infection and inappropriate antibiotic therapy. Resistance was increasingly noted against many antibiotics. The isolates were predominantly resistant to extended spectrum cephalosporins (25%-75%), piperacillin (68%-78%), and gentamicin (23%-69%). The commonest microorganisms causing gram-negative bacteremia were Pseudomonas aeruginosa followed by Klebsiella pneumoniae. The community-acquired bacteremia was mainly due to E. coli. The proportion of preterm and low birth weight babies was significantly high, and the major contributing factor in total mortality. Sensitivity to different antibiotics conclusively proved that a combination of ampicillin + sulbactam with amikacin or ampicillin + sulbactam with ciprofloxacin is most effective.

Neonatal group B streptococcal disease in Finland: a ten-year nationwide study

BACKGROUND

Group B Streptococcus (GBS) is the most common cause of invasive infections in newborns. GBS bacteria are typed on the basis of capsular polysaccharides or surface-localized proteins. Both polysaccharides and protein antigens have been suggested as potential vaccine candidates.

METHODS

A prospective nationwide laboratory-based study of invasive GBS infections in children younger than 3 months of age was conducted in 1985 through 1994. Isolates were serotyped by immunodiffusion in agar gel with HCl extracts and rabbit antisera. Clinical diagnoses and case fatalities were verified from the patient records or the national hospital discharge register.

RESULTS

There were 485 cases registered during the 10-year period. The incidence of disease was 0.76/1000 live births. The case fatality rate was 8.0%. Of the 485 cases 398 (83%) were early onset and 87 (17%) late onset infections. The most common clinical diagnosis was bacteremia (77%) without an identified focus of infection. Other diagnoses included meningitis (17%), pneumonia (3%), osteomyelitis or septic arthritis (2%), pyelonephritis or cellulitis. Serotyping of 395 isolates revealed that 47% were of serotype III or III/R, 23% of Ia/c, 11% of Ib, 6% of II/R, 8% of IV, 1% of V and 7% were nontypable.

CONCLUSIONS

The clinical picture of GBS disease and serotype distribution are similar to what has been reported from other countries. Serotypes III and III/R dominated (47% of all infections), especially in late onset disease. On the basis of these results a GBS vaccine including at least the Ia, Ib, II and III components would provide coverage against 88% of GBS serotypes causing neonatal disease in Finland.

C-reactive protein (CRP) response patterns in neonatal septicaemia

C-reactive protein (CRP) is an unreliable diagnostic tool in the early diagnosis of neonatal septicaemia. However, serial measurements have been shown to be useful in monitoring the effectiveness of treatment. The aim of the present study was to investigate whether a specific CRP response pattern to different groups of pathogens could be identified during treatment of neonatal septicaemia. Serial CRP measurements from day 1 to 4 in monomicrobial blood culture-proven episodes of septicaemia were reviewed. In 4416 admissions, 180 out of 206 positive blood cultures were monomicrobial; 121 monomicrobial septic episodes were eligible for final analysis of the CRP response during treatment. A low median (M) value (day 1 to 4) was identified in coagulase-negative staphylococci (CONS) (M=23 mg/l), contrasting with high median values in Staphylococcus aureus (M=58 mg/l), group B streptococci (M=51 mg/l), Escherichia coli (M=51 mg/l) and Candida species (M=76 mg/l) (p<0.001). Median CRP values in the two groups were different for each of the treatment days 1 to 4 (p<0.001). An increase (p<0.001) in CRP during the 24 h before initiation of treatment was a sign of late-onset CONS septicaemia. In episodes where antimicrobial treatment failed, CRP levels were moderately elevated the day prior to treatment start and increased continuously thereafter, whereas successful treatment was generally accompanied by a decline in CRP in less than 4 days. The CRP response to CONS is significantly less pronounced than to other commonly encountered pathogens in neonatal septicaemia. A rise in CRP beyond the third day of empirical treatment should give rise to a suspicion of fungal infection or ineffective antibacterial treatment.

Rapid conversion of naive to effector T cell function counteracts diminished primary human newborn T cell responses

The reduced incidence of graft versus host disease following the use of human cord blood as a source of stem cells for bone marrow reconstitution challenges our understanding of the immunocompetence of newborn T cells. Newborn CD4+ T cells express mainly the CD45RA phenotype and have been considered to respond comparably to adult CD4+ T cells exhibiting the CD45RA phenotype. We compared the in vitro kinetics of phenotypic conversion of newborn and adult CD4+CD45RA+ T cells to CD4+CD45RO+ T cells. The cytokine profile and B cell helper activity of the converted CD4+CD45RO+ T cell population were also determined. Newborn CD4+CD45RA+ T cells were converted to CD4+CD45RO+ with significantly faster time kinetics than adult CD4+CD45RA+ T cells, following either phytohaemagglutinin (PHA) or anti-CD2 activation. Freshly purified newborn naive T cells did not produce IL-2, IL-4 or interferon-gamma (IFN-gamma) following stimulation, whereas adult naive T cells secreted IL-2 and adult-derived CD4+CD45RO+ T cells secreted all three cytokines under the same stimulatory conditions. However, newborn and adult CD4+CD45RA+ T cells, following primary stimulation and maturation in vitro, acquired the ability to secrete a Th1-type cytokine profile of IL-2 and IFN-gamma after secondary stimulation. Newborn CD4+ naive T cells that acquired the CD45RO phenotype in vitro also gained B cell helper activity equivalent to that of adult in vitro matured CD4+ naive T cells. These findings suggest that newborn and adult CD4+CD45RA+ T cell subsets are differentially responsive to various stimuli. They show that newborn CD4+CD45RA+ naive T cells can transform more quickly than their adult counterparts into functionally equivalent CD4+CD45RO+ T cells, a process that may be important to counteract the immature immune environment which exists in the newborn.

Mortality from early onset group B streptococcal infection in the United Kingdom

AIMS

To assess the assumption that group B streptococcal infection is less common in the United Kingdom than it is in the United States.

METHODS

All stillbirth and neonatal death records in the former Northern Health Region were scrutinised to determine how many babies had died of infection in 1981-96, and what had been the cause.

RESULTS

Fifty one of 630 206 live born babies had died of confirmed group B streptococcal infection after becoming symptomatic within 48 hours of birth (0.8 neonatal deaths per 10,000 live births). There were a further 27 deaths from infection without a confirmed microbiological diagnosis, and 17 stillbirths from confirmed group B streptococcal infection.

CONCLUSIONS

The incidence of death from early onset infection was marginally higher than the officially estimated rate for the United States before widespread prophylaxis was attempted. Strategies for perinatal prevention deserve greater attention in the United Kingdom.

Antibiotic susceptibility of blood culture isolates after nearly two decades with netilmicin and ampicillin in neonatal septicaemia

The aim of the study was to investigate the in vitro antibiotic susceptibility of blood culture isolates after almost 20 years with ampicillin and methicillin as empirical treatment for neonatal septicaemia. All blood culture isolates and their antibiograms obtained in a single tertiary neonatal intensive care unit from 1 January 1989 to 31 December 1994 were reviewed. Two hundred and six blood cultures from 181 infants containing 223 bacterial and 11 fungal isolates were identified during 4416 admissions. Fifteen (6.7%) of the bacterial isolates were resistant to ampicillin and netilmicin. Fourteen per cent of the staphylococcal spp. were susceptible to penicillin while more than 90% were susceptible to netilmicin. The coagulase-negative staphylococci (CONS) were resistant to netilmicin, methicillin and gentamicin in 12%, 49% and 65%, respectively. Eighty-nine per cent of the methicillin-resistant CONS were susceptible to netilmicin as opposed to 17% to gentamicin (p<0.001). Except for one strain of Acinetobacter sp., all Gram-negative bacteria were susceptible to netilmicin. Our data show that the ampicillin-netilmicin combination still provides a high in vitro coverage (93%) against bacteria identified in blood cultures from newborns in our unit. Netilmicin has a significantly better in vitro effectiveness against CONS than gentamicin.

Blood culture isolates during 6 years in a tertiary neonatal intensive care unit

Blood culture results obtained in a single tertiary neonatal intensive care unit are reviewed. In 4416 admissions occurring over 6 y we identified 206 positive cultures (4.7/100 admissions) growing 234 bacterial and fungal isolates in 182 infants. Very early and early onset positive cultures comprised 17% and 22% each. Gram-positive bacteria dominated in very early (61%), early (91%) and late onset (78%) cultures with coagulase-negative staphylococci (CONS) as the most frequent isolate in all groups (22%, 46% and 55%, respectively). The 3 most frequent isolates following CONS were in very early onset cultures Escherichia coli (19%), anaerobic bacteria (17%) and group B streptococci (GBS) (14%), in early onset cultures Staphylococcus aureus (28%), Enterococci (7%), E. coli (6%) and Viridans streptococci (6%) and in late onset cultures S. aureus (15%), Candida species (8%) and E. coli (5%). Infants < or = 999 g birthweight, representing 6% of the admissions, contracted 37% of the positive blood cultures and nearly half (44%) of the CONS isolates. In these patients, a significant increase (p < 0.001) in the number of positive cultures/100 admissions and in the proportion of positive cultures in conjunction with an intravascular catheter were seen (p < 0.001). An intravascular catheter was more often present when CONS were isolated as compared to other organisms (p < 0.05). 23 positive cultures (11.2%), most frequently E. coli, were associated with a fatal outcome. Our microbiological pattern is dominated by a gram-positive flora, which is in agreement with recent European and North American reports, but differs from earlier Scandinavian studies in the proportion of CONS and GBS reported.

Decline in sepsis-associated neonatal and infant deaths in the United States, 1979 through 1994

BACKGROUND

Infant mortality in the United States has continued to decline in recent years, but changes in sepsis-associated deaths among infants have not been evaluated previously.

METHODS

Data from US death records were analyzed for the period 1979 through 1994 to assess trends in sepsis-associated deaths among newborns and older infants.

RESULTS

Annual neonatal mortality associated with sepsis declined by 25% from 50.5 deaths per 100 000 live births in 1979 through 1981 to 38.0 deaths per 100 000 live births in 1992 through 1994. Although infant mortality associated with sepsis declined from 71.7 to 56.4 per 100 000 live births over the same period, this decline was attributable to lower sepsis-related mortality among newborns. The rates of sepsis-associated deaths declined for both preterm and term deliveries. Approximately 2260 infants (1521 of whom were newborns) died of sepsis per year in 1992 through 1994. Sepsis-associated death was more likely to occur among infants who were male, black, preterm, or born in the South. Among black infants, the racial gap in sepsis-associated mortality was greater for term than for preterm infants.

CONCLUSIONS

Despite declines in the overall sepsis-related mortality among newborns, racial and regional gaps in mortality persisted over the 16-year study period. Almost half of the sepsis-related deaths occurred among infants who were born prematurely. Disproportionate rates of prematurity among blacks and infants born in the South may have contributed to persistently high sepsis-related mortality in these groups. Future efforts to reduce the incidence of sepsis-associated deaths will depend on targeting higher risk populations and reducing prematurity.

Predisposing conditions and pathogens in bacteremia in hospitalized children

Between 1985 and 1995, 1037 bacteremic episodes were recorded in a pediatric tertiary care center and analyzed retrospectively. Gram-positive bacteria accounted for 719 episodes (68%), gram-negative bacteria for 303 (29%), fungi for 16 (2%), and anaerobes for 12 (1%). In 526 (51%) patients, primarily neonates and oncology patients, a predisposing condition was present. In 390 (38%) episodes a clinical source of infection was documented. Mortality was highest in Pseudomonas bacteremia (45%). Since the bacterial spectrum differed widely between patient groups, the choice of empirical antimicrobial therapy should be based on any underlying condition present in the patient and the clinical source of infection. As anaerobes were rarely isolated. the routine use of anaerobic blood cultures in patients without predisposing conditions does not seem warranted.

Increase of staphylococci in neonatal septicaemia: a fourteen-year study

All cases of neonatal septicaemia during 1981-94 were studied at Orebro Medical Centre Hospital, Sweden. One hundred and thirty-two children fulfilled laboratory and clinical criteria for neonatal septicaemia and were included. Staphylococcus aureus (n = 41), Group B streptococcus (GBS) (n = 32) and coagulase-negative staphylococci (CoNS) (n = 27) were the dominating aetiologies. The annual incidence of septicaemia increased significantly, from 2.3 cases during the first 7-year period to 3.3 per 1000 live births during 1988-94. This increase was caused by S. aureus and CoNS, which mainly affected premature children and had an onset more than 48 h after delivery. GBS, on the other hand, slightly decreased and affected full-term children within 48 h. The overall mortality was 11%. CoNS isolated during the latter 7-year period were more resistant to antibiotics than those isolated during 1981-87; resistance to methicillin increased from 14 to 45% and to gentamicin from 0 to 20%. These changes in aetiology and antibiotic susceptibility should be considered when selecting antibiotic treatment in neonatal septicaemia.

Fatal sepsis caused by Corynebacterium amycolatum in a premature infant

Corynebacterium amycolatum has not been reported as a cause of human infections up to now, but usually the bacterium is misidentified in clinical specimens as Corynebacterium xerosis. We report the first case of neonatal sepsis due to Corynebacterium amycolatum with a fatal outcome in a premature infant.

Neonatal bacterial sepsis in a neonatal intensive care unit: a 5 year analysis

OBJECTIVE

To study the pattern of neonatal sepsis in a neonatal intensive care unit (NICU) during a 5 year period and assess the relationship between maternal risk factors and early onset sepsis (EOS).

METHODOLOGY

The study reported here was a retrospective analysis of 209 episodes of septicaemia and 5 episodes of bacterial meningitis in 198 newborn infants, 22 of whom died. Eighty-one infants had EOS (< or = 72 h) and 117 infants had late onset sepsis (LOS > 72 h). All infants had clinical evidence of sepsis, a computerized haematological score for sepsis of 4 or greater, and either treatment with antibiotics for 7 days or more or had earlier death due to sepsis. The organisms causing neonatal sepsis were analyzed according to the day of onset, gestational age, birthweight and year of infection.

RESULTS

Sepsis occurred in 5.6 per 1000 live births and 3.8% of NICU admissions. There were 81 episodes of EOS and 128 of LOS. Coagulase negative staphylococci (CONS) 38.8%, group B Streptococcus (GBS) 20.1% and Gram-negative bacilli (GNB) 20.1% were the common causes of sepsis; and GBS (50.6%) and CONS (60.9%) were the most common organisms in EOS and LOS, respectively. The mean gestational age and birthweight were higher in babies with EOS than compared with LOS. The higher likelihood of probable rather than definite infection in infants with EOS was related to more mothers in the EOS group receiving intrapartum antibiotics. GNB infection was more common in their babies.

CONCLUSIONS

GBS and CONS were the most common causes of EOS and LOS, respectively. The use of maternal intrapartum antibiotics interferes with neonatal blood culture results. Because blood cultures are not always positive in neonatal septicaemia, a combination of clinical, haematological and other microbiological evidence should be used when diagnosing neonatal septicaemia.

Early-onset sepsis in very low birth weight neonates: a report from the National Institute of Child Health and Human Development Neonatal Research Network

OBJECTIVE

Early-onset sepsis (occurring within 72 hours of birth) is included in the differential diagnosis of most very low birth weight (VLBW) neonates. To determine the current incidence of early-onset sepsis, risk factors for disease, and the impact of early-onset sepsis on subsequent hospital course, we studied a cohort of 7861 VLBW neonates (401 to 1500 gm) admitted to the 12 National Institute of Child Health and Human Development (NICHD) Neonatal Research Network centers during a 32-month period (1991-1993).

METHODS

The NICHD Neonatal Research Network maintains a prospectively collected registry on all VLBW neonates born or cared for at participating centers. Data from this registry were analyzed retrospectively.

RESULTS

Blood culture-proven early-onset sepsis was uncommon, occurring in only 1.9% of VLBW neonates. Group B streptococcus was the most frequent pathogen associated with early-onset sepsis (31%), followed by Escherichia coli (16%) and Haemophilus influenzae (12%). Decreasing gestational age was associated with increased rates of infection. Antibiotic therapy for suspected sepsis is frequently initiated at birth in VLBW neonates. Almost half of the infants in this cohort were considered to have clinical sepsis and continued to receive antibiotics for 5 or more days, despite a negative blood culture result in 98% of cases. These findings underscore the difficulty of ruling out sepsis in the symptomatic immature neonate and the special concern for culture-negative clinical sepsis in the face of maternal antibiotic use. Neonates with early-onset sepsis were significantly more likely to have subsequent comorbidities, including severe intraventricular hemorrhage, patent ductus arteriosus, and prolonged assisted ventilation. Although 26% of VLBW neonates with early-onset sepsis died, only 4% of the 950 deaths that occurred in the first 72 hours of life were attributed to infection. For those infants discharged alive, early-onset sepsis was associated with a significantly prolonged hospital stay (86 vs 69 days; p <0.02).

CONCLUSIONS

Early-onset sepsis remains an important but uncommon problem among VLBW preterm infants. Improved diagnostic strategies are needed to enable the clinician to distinguish between the infected and the uninfected VLBW neonate with symptoms and to target continued antibiotic therapy to those who are truly infected.

Neonatal bacterial septicemia in a tropical area. Four-year experience in Guadeloupe (French West Indies)

During a four-year study (1987-1990) at the Neonatal Department, University Hospital Pointe-à-Pitre (French West Indies), blood culture was systematically performed on all admitted newborns. The incidence of septicemia was 48 of 1000 admissions and 8.9 of 1000 inborn live births. Among the 107 neonatal positive blood cultures, group B streptococcus accounted for 37% of blood culture isolates and was the most frequent cause of septicemia. The overall mortality rate was 8.4%. The incidence of neonatal bacterial septicemia was among the high rates reported in the literature. The incidence of neonatal bacterial septicemia is discussed as a public health problem in perinatology in Guadeloupe in spite of good medical care. A review of the literature on bacterial septicemia in tropical or developing countries compared to the Guadeloupean experience allows speculation that this problem might be underestimated in third world countries.

Clinical profile of klebsiella septicemia in neonates

A detailed clinical study of 51 consecutive cases of neonatal klebsiella septicemia was carried out prospectively over a 20 months period. The incidence was 6.27 per 1000 live births. Majority (85.5%) were either preterms or small for date. Almost fifty percent babies had associated perinatal risk factors. Mean age of onset was 5.7 +/- 2.2 days. General symptoms were the earliest to occur at mean age of 5.7 days followed by respiratory, alimentary, hematological and neurological symptoms at 6.2, 6.3, 6.6 and 7.9 days respectively. About half of the neonates had associated complications; commoner being meningitis (20%), bleeding manifestations and sclerema (17.6% each) and pneumonia (15.7%). Cefatoxime was found to be the drug of choice (86% sensitivity). Nine babies (17.6%) died during the study period at a mean age of 9.1 +/- 3.2 days. Mean duration of hospital stay in rest of neonates was 27.9 +/- 12.1 days. Neurological symptoms were commoner in late onset disease. Bleeding manifestations, sclerema and granulocytopenia were seen exclusively in preterms. Presence of respiratory symptoms, bleeding, sclerema, shock and granulocytopenia were identified as poor prognostic factors in neonatal klebsiella septicemia.

Properties and type antigen patterns of group B streptococcal isolates from pigs and nutrias

All 59 group B streptococcal cultures isolated from pigs and nutrias reacted with group B-specific antiserum and gave a positive CAMP reaction in the zone of staphylococcal beta-lysin. Most of the cultures were pigmented; all cultures hydrolyzed Na hippurate and utilized salicin, maltose, and saccharose but not esculin, mannitol, or inulin. Fifty-three percent of the group B streptococci from pigs and none of those from nutrias were lactose positive. Serotyping revealed that most of the group B streptococci from pigs were of serotype III and most of those from nutrias were of type Ia/c. Protein c was present as c beta antigen. All group B streptococci were susceptible to penicillin and bacitracin (10 U), and most of the porcine cultures were resistant to tetracycline. According to these results, group B streptococci from pigs and nutrias differ from bovine and human group B streptococci and seem to play no role in cross-infections between animals or between animals and humans.

S-fimbriae mediated adhesion of Escherichia coli to human buccal epithelial cells is age independent

S-fimbriated Escherichia coli, which cause sepsis and meningitis in the newborn, bind to sialic acid-containing glycoprotein structures on the surface of human buccal epithelial cells. The dependence of this binding on host age was examined. S-fimbriated E. coli adhered in comparable numbers to cells in newborns, infants, children and adults (23.0 +/- 8.6; 23.1 +/- 11.5; 24.7 +/- 7.9; 28.9 +/- 8.8). Thus, the increased susceptibility of neonates to infections caused by S-fimbriated E. coli cannot be explained by enhanced adhesion to epithelial cells.

Neonatal sepsis in Pakistan. Presentation and pathogens

The case records of all neonates admitted to the neonatal unit at Aga Khan University Hospital (Karachi) in a 30 month period (Nov. 86-April 89) were analysed. Of 60 neonates with confirmed sepsis, 33 (55%) had non-nosocomial infection (NNC) whereas 27 (45%) had nosocomial sepsis (NC). The most common organisms causing early-onset NNC sepsis were Klebsiella species (53%) and Escherichia coli (10%), whereas the organisms causing late-onset NNC sepsis included Salmonella parathypi (21%), Group A Streptococcus (21%), Escherichia coli (14%) and Pseudomonas species (14%). Klebsiella was the most common organism causing NC sepsis, others being Staphylococcus aureus (15%) and Serratia species (15%). The mortality in NC sepsis, early-onset and late onset NNC sepsis was 44%, 26% and 43%, respectively. Risk factors associated with NNC sepsis included low birthweight, prematurity and prolonged and complicated deliveries. There was a high incidence of drug resistance to ampicillin and gentamicin among gram-negative organisms causing sepsis (mean 67%).

Neonatal sepsis in an intensive care unit and results of treatment

Incidence and fatality of neonatal sepsis in intensive care units have been relatively high despite progress in the management of very ill neonates and combined treatment of sepsis with antibiotics. Between 1985 and 1989 944 children (632 premature babies and 312 term babies) were treated in the intensive care unit of the University Children's Hospital of Kiel. The incidence of sepsis was 5% (congenital sepsis 4%, sepsis acquired after birth 1%). Pneumonia occurred in 4% (congenital pneumonia in 2%, postnatal pneumonia in 2%). Early diagnosis and treatment with piperacillin plus cefotaxime reduced the mortality rate of sepsis to 2%. Sepsis never developed under treatment with piperacillin plus cefotaxime. Early recognition of neonatal sepsis by a good blood culture technique and beginning of treatment on first suspicion of sepsis with cefotaxime and piperacillin can improve the results especially in intensive care patients.

Breast feeding and protection against neonatal sepsis in a high risk population

Protection against neonatal sepsis by breast feeding was investigated in a developing community. A case-control study was carried out with 42 cases from a hospital and 270 controls, matched for age and socioeconomic conditions from the community. Exclusive breast feeding was extremely rare, most babies being partially breast fed and a few being given formula feed or animal milk. A highly significant odds ratio of 18 was obtained, showing that even partial breast feeding protects against neonatal sepsis in such a population.

Neonatal Haemophilus influenzae infections

Nine cases of neonatal Haemophilus influenzae septicaemia were recorded in Finland during 1985-9; incidence was 2.8/100,000 live births, and 1.6% of all cases of neonatal septicaemia. The onset of the disease was early in all cases, ranging from 0-6 hours after delivery. Seven of the infants were preterm and three died (overall mortality 33%). H influenzae was isolated from blood in seven of the cases, and in two neonates with clinical signs of septicaemia it was found on several surface sites and the placenta. One of the eight strains of H influenzae was capsular type b and biotype I, the rest being non-typable--a distribution similar to those previously reported. Four of the uncapsulated strains were of biotype III, and three were of biotype II. None of the strains of H influenzae was of biotype IV, which has been reported to be characteristic of neonatal and genital isolates of H influenzae. All nine mothers had some sign of infection at the time of or shortly after delivery. H influenzae was isolated from five mothers: from the blood (n = 1) or from the placenta or cervix (n = 4). The use of intrauterine devices may be a possible risk factor for neonatal H influenzae infections; two of the mothers had such devices in place during their pregnancies.

Epidemiology of neonatal disorders of respiration

It is well known that signs of respiratory distress or disease (RD), such as high breathing frequency, chest wall retractions, grunting, and cyanosis, are common in newborn infants. The signs may be very transient or develop into a potentially life-threatening condition. When they are first observed, they often have a very ambiguous prognostic significance.

Incidence and etiology of neonatal septicaemia and meningitis in western Sweden 1975-1986

In a retrospective study of neonatal septicaemia and meningitis in a defined region of western Sweden 1975-1986, 231 cases were identified. The incidence was 2.8/1000 live births. The case-fatality rate was 15%. thirty-three patients had meningitis. Only 55 patients (24%) had no known risk factors. Preterm delivery was a most important risk factor for both morbidity and mortality. The most common causative organisms were group B streptococci, Staphylococcus aureus and aerobic Gram-negative rods, together isolated from 82% of the patients. The cases were approximately equally divided between very early, early and late onset infections. Group B streptococci were over-represented in very early onset infections in all birthweight groups and aerobic Gram-negative rods were the most common isolates from low birthweight infants with late onset infections. However, group B streptococci, Staphylococcus aureus and Gram-negative rods were found in all birthweight and gestational age groups. Thus, initial antimicrobial therapy must be equally broad in all neonates with suspected septicaemia.