Serum cholesterol and bowel flora in the newborn.

Bottle-fed infants have a total serum cholesterol of 147 mg/100 ml on the fifth day of life and their stools contain more Escherichia coli than Lactobacilli organisms. The ratio of these bacteria can be reversed by adding bicarbonate or Lactobacilli to feeds. This change is associated with a decrease in total cholesterol to a mean 119 mg/100 ml over the next 3 days. Lactobacilli organisms predominate in the stools when serum cholesterol is low and may play a role in the metabolism of cholesterol.

Improved specificity of in vitro anti-HIV antibody production: implications for diagnosis and timing of transmission in infants born to HIV-seropositive mothers.

In vitro anti-HIV antibody production (IVAP), initially introduced as a method for diagnosis of human immunodeficiency virus type 1 (HIV-1) infection in infants, has been limited in its application because of poor specificity and sensitivity early in life. The aims of this study were to improve the specificity of the IVAP assay and to evaluate its sensitivity in conjunction with assays of HIV culture, polymerase chain reaction (PCR), and p24 antigen. To prevent false-positive reactions resulting from maternal serum-derived cytophilic anti-HIV IgG, additional preculture and washing steps for peripheral blood mononuclear cells (PBMCs) were introduced that resulted in dramatic improvement in specificity of IVAP. The sensitivity of the revised IVAP at age < 3 months in 20 infected infants was, however, only 25%; of 15 infected infants initially negative in IVAP, 13 became positive at a mean estimated age of 4.4 +/- 1.8 months. When correlated with virological assays, a failure to respond in IVAP at age < 1 month was often associated with negative virological identification, whereas a positive IVAP response at age < 3 months was always associated with positive results in all virological assays. Moreover, conversion from negative IVAP to positive responses occurred subsequent to, and not concurrently with, a positive virological identification of infected infants. The revised IVAP methodology renders this assay potentially useful as an additional tool not only for the diagnosis of HIV infection, but for estimating timing of maternal-infant HIV transmission as well.

Malassezia furfur skin colonization in infancy.

Malassezia furfur, a lipophilic yeast, has become recognized as a cause of sepsis in infants receiving parenteral fat emulsions via indwelling deep venous catheters. Colonization of infants' skin may be a prerequisite to colonization of the intravascular catheter and subsequent infection with M furfur. Three hundred ninety-three surveillance cultures were performed on 146 infants during their first 12 weeks of hospitalization in the intensive care unit (ICU) or the neonatal transitional unit (NTU). In addition, 47 full-term newborn infants and 38 healthy infants in the well-baby clinic were cultured. Colonization rates were greatest (48%) during the second month of hospitalization for the infants in the ICU/NTU group. In contrast, 0 of 47 newborn infants and 2 of 38 healthy infants were colonized. Prematurity and a prolonged length of stay were identified as risk factors for colonization.

Recovery of HIV-related retroviruses from Italian patients with AIDS or AIDS-related complex and from asymptomatic at-risk individuals.

Human retroviruses have been detected in supernatants of cultures of Ficoll-enriched lymphocytes from peripheral blood, lymph nodes and bone marrow of (a) 32 out of 42 patients with Acquired Immunodeficiency Syndrome (AIDS), (b) 34 out of 64 patients with AIDS-related Complex (ARC), (c) 9 out of 18 asymptomatic children born from Human Immunodeficiency Virus (HIV) seropositive mothers, and (d) 9 out of 28 asymptomatic drug abusers or hemophiliacs. Virus detection was monitored by assaying culture supernatants for the presence of Mg++-dependent reverse transcriptase (R.T.) activity. A number of these virus-positive sups were passaged repeatedly in cultures of phytohemagglutinin-stimulated and Interleukin-2 (IL-2) treated fresh lymphocytes from healthy blood donors. Occasionally, multiple samples were obtained at varying time intervals from the same patient and consistently yielded detectable retroviral activity. Several isolates were characterized as closely related if not identical to HIV, HTLV-IIIB strain, since cells from either patients' own lymphocyte cultures or subcultures infected with passaged virus were stained in an indirect immunofluorescent assay with both patients sera and monoclonal antibody against p24 antigen of the HTLV-IIIB strain. Representative isolates, grown on fresh lymphocytes of healthy donors and metabolically labelled with 35S-cysteine, were also analyzed in a radioimmunoprecipitation assay (RIPA) against patients' sera to define their antigenic pattern, which was widely superimposable to that obtained with HTLV-IIIB-infected H9 cells. DNA from lymphocytes infected with 2 representative isolates were Southern-blotted and probed with an insert from a plasmid containing the entire genome of the HTLV-IIIB strain. The hybridization patterns were comparable with those obtained with DNA from H9-infected cells.

Explanation for false-positive urine cultures obtained by bag technique.

OBJECTIVE: To test whether a urine bag technique, previously shown in circumcised male infants 1 month to 1 year of age to yield no false-positive cultures, would give similar results in newborns (females and circumcised and uncircumcised males). DESIGN: Prospective study in which periurethral and urine specimens were obtained from healthy newborns. After the periurethral specimen was obtained, the perineum was washed and a urine bag applied. The urine bag was removed immediately after voiding and the urine was cultured. SETTING: Normal newborn nursery and pediatric hospital. SUBJECTS: Ninety-eight healthy full-term newborns (49 female and 49 male) admitted to the normal nursery during a 4-month period. MAIN RESULTS: Isolation of a pathogen from the bag urine reflected periurethral flora. In 20 (95%) of the 21 urine specimens from which a pathogen was isolated, the same pathogen was detected on the periurethra. Sixteen of the 21 urine cultures were falsely positive (> 10(4) colony-forming units of pathogen per milliliter). In 50 (98%) of the 52 urine samples that yielded no growth, the periurethral culture was also negative. In the remaining 25 urine samples in which nonpathogens were detected, the periurethra yielded nonpathogens or no growth. Thus, if a pathogen was isolated from a bag urine sample, the same pathogen was detected on the periurethra 95% of the time. Conversely, if the bag urine sample was negative for a pathogen, the periurethral culture was negative 100% of the time. The presence of a pathogen on the periurethra was more common in female than male neonates (16 of 49 vs four of 49; P = .004), and none of the 14 circumcised male neonates had a pathogen detected on their periurethra or in their urine. CONCLUSION: This study explains the finding of false-positive cultures with the bag technique. Pathogens detected in bag urine samples reflected pathogens on the periurethra. Until a bag collection technique that avoids contamination by periurethral flora can be developed, urethral catheterization and suprapubic aspiration remain the methods of choice for obtaining a urine specimen in female and uncircumcised male neonates.

Influence of age on faecal carriage of P-fimbriated Escherichia coli and other gram-negative bacteria in hospitalized neonates.

The aerobic faecal flora of 953 infants aged over 5 days was studied on discharge from 22 neonatal wards in Swedish hospitals. Klebsiella/enterobacter was isolated from 74% of infants and dominated the aerobic gram-negative flora in 19 wards. Escherichia coli was carried by 42% and showed a slight dominance in two wards. Initially klebsiella/enterobacter dominated the flora but became increasingly mixed with and taken over by E. coli, carriage increasing from 21% in infants discharged after 5-7 days to 57% after 3 weeks or later. Among infants with E. coli, P-fimbriated strains were demonstrated in 23% (range 0-67) and were independent of age. Occasional clustering of such strains was observed in 3/22 wards during the study period. It is postulated that the general and local colonization patterns observed reflect differences between individual strains of E. coli and klebsiella in both their capacity for transmission and their persistence in the newborn gut. The role of P-fimbriae in intestinal colonization of neonates by E. coli was, however, not supported.

The bacterial flora of neonates in intensive care-monitoring and manipulation.

Unlike healthy babies, newborns hospitalized in the neonatal intensive care unit (NICU) are colonized with bacterial flora that reflects their exposure to pathogens in the NICU, not bacterial acquired from mother in the perinatal period. For example, nosocomial Gram-negative bacilli, such as klebsiella, enterobacter, and citrobacter but not Escherichia coli tend to colonize the gastrointestinal tract. Colonization with Gram-negative bacilli generally is a prerequisite for nosocomial infection with these pathogens, but surveillance cultures may not be a cost effective approach to predicting which babies will ultimately become ill. However, screening cultures to detect the emergence of antibiotic-resistant Gram-negative bacilli facilitate containment and guide empiric antibiotic therapy, and surveillance cultures are necessary to detect colonized babies when nosocomial Gram-negative bacilli become epidemic in the NICU. Such cultures are inexpensive and easy to perform if appropriate selective media are used. Surveillance cultures to detect coagulase-negative staphylococci, which numerous investigators claim are increasingly important NICU pathogens, are of little value since colonization is virtually universal in the first week of life. Documentation of colonization with group B streptococci or Staphylococcus aureus also cannot be justified on a routine basis. Screening for methicillin-resistant S. aureus, however, may be indicated since early detection of these strains can limit dissemination in the NICU. Research aimed at restoring colonization resistance with elements of normal bacterial flora or preventing colonization by nosocomial pathogens is in its infancy.

Outbreak of colonization of neonates with Enterobacter sakazakii.

An outbreak of colonization of 11 neonates with Enterobacter sakazakii occurred in a neonatal intensive care unit from the 10 September to 17 October 1984. During this period Ent. sakazakii was isolated from throat and rectal swabs and tracheal aspirates, but not from blood, of the neonates. The duration of colonization ranged from 2 to 8 weeks. The isolates were resistant to amikacin and to tobramycin, but sensitive to gentamicin. Four of the 11 colonized neonates had clinical signs of severe sepsis and one of meningitis and four died in spite of intensive chemotherapy. The source and the mode of spread of Ent. sakazakii remained unknown as it was not found on the hands of staff or in the inanimate environment of the unit. Ent. sakazakii may be implicated in severe infections in neonates and should be included when screening clinical specimens.

Screening for enteropathogenic Escherichia coli.

In an attempt to identify the prevalence of enteropathogenic Escherichia coli (EPEC) carriage and to minimize the chances of admitting a baby to the neonatal wards with unsuspected EPEC infection, 27,174 maternity patients admitted in labour and 4049 neonates admitted to the Special Care Baby Unit (SCBU) were screened for intestinal carriage of common EPEC serotypes. Two hundred and sixty-five (1%) maternity patients were positive, of whom 8 (3%) had diarrhoea. Of the babies born to these mothers, 10 (3.8%) were infected with EPEC and in each the serotype was the same as the mother's. Nine neonates (0.2%) admitted to the SCBU were also found to be infected with EPEC. Seven of the 19 babies (37%) had diarrhoea. Symptomatic mothers or babies were nursed in isolation. During the 8 year period under study no incidents of cross-infection with EPEC occurred.

Colonization with coagulase-negative staphylococci in two neonatal units.

Episodes of septicaemia due to coagulase-negative staphylococci (CNS) were more frequent in a level III than in a level II neonatal unit in Stockholm, Sweden. Colonization with CNS during the first 2 weeks of life was investigated in 10 infants from each unit. As the use of antibiotics differed between the two units, the aim was to correlate colonization and antimicrobial resistance patterns to antibiotic usage. Antimicrobial susceptibility of CNS to isoxazolylpenicillins, co-trimoxazole, erythromycin, clindamycin, chloramphenicol and gentamicin was determined. Selected isolates were typed with restriction endonuclease analysis of plasmid DNA and of genomic DNA. Infants were frequently colonized with multiple strains and species of CNS, and transmission of strains from patient to patient occurred within the unit. Qualitative and quantitative differences in antibiotic use were not correlated with colonization. The prevalence of resistant isolates, mostly of Staphylococcus haemolyticus, was higher in the level II unit with lower use of antibiotics. Staphylococcus epidermidis, which is generally more virulent, prevailed in the level III unit, where there were more severely ill children and invasive procedures were more frequently performed.

Asymptomatic neonatal contamination with herpes simplex virus.

Frequent maternal vaginal and/or lesion cultures for herpes simplex virus (HSV) were obtained from a high-risk maternal population during the course of pregnancy and from oropharyngeal samples of their newborn infants on the first day of life to determine (1) the incidence of asymptomatic neonatal contamination with HSV and (2) the relationship of neonatal with maternal colonization. Four hundred ninety-nine maternal cultures were obtained from 85 patients. The mean number of cultures per patient was six with a range from one to 12. Thirty-three mothers had 41 positive cultures. Fifty-two women had 301 negative cultures. Cord blood HSV-enzyme-linked immunosorbent assay (ELISA) titers were not different in the two groups of infants (geometric mean titer 1152 and 800, respectively). One infant from each maternal group had a positive oropharyngeal HSV culture. Both infants were asymptomatic. One was delivered by elective cesarean section at term to a mother with four positive cultures obtained during pregnancy. Fetal membranes were intact until delivery. The second infant with a positive oropharyngeal culture on the first day of life was born vaginally to a mother with seven negative cultures during pregnancy. Repeat cultures on both infants during the first week of life were negative. These data indicate that asymptomatic neonatal contamination with HSV does occur in oropharyngeal samples obtained on the first day of life. The data also suggest that there is a poor relationship of viral excretion during pregnancy or the mode of delivery with neonatal contamination. Further data are required to determine the incidence of asymptomatic neonatal contamination and the relationship of maternal with neonatal cultures.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute phase reactants in neonatal bacterial infection.

The C-reactive protein (CRP) level was evaluated in 142 infants requiring investigation for suspected infection. After excluding two neonates because of incomplete data, there remained 140 neonates, of whom 16 had septicemia. Fifteen of 16 had increased CRP levels. The CRP value was not elevated in any baby (n = 5) who had positive blood cultures for Staphylococcus epidermidis, all of whom had an uneventful clinical course. The CRP level was elevated in all six babies with meconium-aspiration syndrome, but was normal in five infants whose viral cultures were positive. Ninety-nine percent of uninfected babies had normal CRP values. Overall, CRP was a valuable test for diagnostic confirmation of bacterial infection. Elevated CRP level was always accompanied by at least one abnormality in the other tests performed. Although the study was not intended to predict clinical onset of bacterial disease, our results suggest that the CRP level, because of a high negative predictive value, may be useful in ruling out bacterial infection.

Natural transmission of group B Streptococcus during delivery.

This is a study of group B Streptococcus during labor of 121 patients in whom group B Streptococcus was isolated in the vagina and/or rectum before delivery. The intrapartum vaginal culture was positive in 55.2% of the antepartum carriers (32/58). When the vaginal culture during delivery was positive, the group B Streptococcus was isolated in the amniotic fluid 2 h after the rupture of membranes in 81% of the cases. The newborns of antepartum carriers, when the labor developed naturally, were colonized by group B Streptococcus in 69.2% of cases when the intrapartum vaginal and/or amniotic fluid cultures were positive (9/13), while only 5.6% of the newborns of antepartum carriers but with negative cultures during delivery were colonized by group B Streptococcus (1/18). The most frequent positive neonatal culture was in the umbilicus (83.3%) followed by the external ear (62.5%).

Bacteriological nasal flora in newborns indicating health and/or development of infection.

During delivery, a fetus otherwise sterile during the intrauterine life, comes in contact with bacterial flora of the mother's birth canal, and then also with the ward personnel's skin and respiratory system flora. Due to the absence of competitive bacteriological flora, the nasal cavity is gradually colonized by microorganisms, especially those with a capacity of adhesion to epithelial cells of respiratory nasal mucosa. Bacteriological flora of the newborn's nasal flora was observed on days 1 and 3 postpartum, in an attempt to determine whether a finding of pathogenic bacterial flora in newborn's nasal mucosa indicates a localized infection only or points to the possible development of generalized infection. Bacteriological nasal flora was monitored in infants born by spontaneous delivery and in those born by cesarean section. In mothers of infants born by spontaneous delivery, bacteriological flora from the cervix uteri was investigated. Results of the study performed by usual methods revealed Escherichia coli and Staphylococcus aureus to prevail in the pathogenic flora. Gram-negative microorganisms were found to be good indicators of local infection of newborn's nasal mucosa, regardless of the absence of clinical symptoms.

A study of microbial flora of conjunctival sac in newborns.

During the period from July to August 1987, the microbial flora in conjunctival sac of 93 newborns (186 eyes: normal vaginal delivery) and 19 newborns (38 eyes: cesarean section delivery) in nursery of Ewha Womans University Hospital were investigated for isolation and identification of bacteria on delivery day and on two days after birth. The results of the investigation are as follows: 1. Of 186 eyes (normal vaginal delivery), bacterial growth of one species was shown in 40 eyes (21.5%) on delivery day and in 64 eyes (34.4%) on two days after birth. Bacterial growth of two species shown in 10 eyes (5.4%) on delivery day and in 10 eyes (5.4%) on two days after birth. 2. Of 38 eyes (cesarean section delivery), bacterial growth of one species was shown in 2 eyes (5.3%) on delivery day and in 20 eyes (52.6%) on two days after birth. Bacterial growth of two species was shown 2 eyes (5.3%) on two days after birth. 3. Several kinds of bacterial species were isolated in normal vaginal delivery and cesarean section delivery. Staphylococcus epidermidis, Escherichia coli, Staphylococcus aureus were isolated.

Carriage of beta haemolytic streptococci (BHS) in pregnant women and acquisition by neonates.

Beta Haemolytic Streptococci(BHS) carriage rate in pregnant women during labour and its acquisition by their newborns just after birth was investigated in 60 mother baby pairs. The carriage rate of group B Streptococci (GBS) was 11.6%, acquisition rate by newborns of carrier and non-carrier mothers was 85.7% and 1.8% respectively. A total of 28.5% newborns were carrying GBS on all the skin sites and were heavily colonized and therefore, at higher risk of developing early onset of Streptococcal infections. Penicillin G and Ampicillin were most effective antibiotics against GBS.

[Microbial colonization and succession on the faucial mucosa in newborn infants rooming in with their mothers in a maternity hospital]. / Mikrobnaia kolonizatsiia i suktsessiia na slizistoi obolochke zeva u novorozhdennykh detei pri sovmestnom s mater'iu prebyvanii v akusherskom statsionare.

The formation of microflora on the laryngeal mucosa in newborn infants during the first 5 days of their life was studied in one of the maternity hospitals of Moscow. In this work modern methods of the isolation and identification of aerobic and anaerobic microorganisms were used, and the results thus obtained were computer-processed. In the maternity hospital of the "mother-child" type the microbial colonization of the laryngeal mucosa by normal and opportunistic microorganisms was noted in newborn infants. A wave-like course of the formation of laryngeal microflora, indicative of microbial succession occurring in the child, was revealed. The attempt to establish the cases of microbial interference between the species colonizing the laryngeal mucosa revealed that it was very rarely observed in 5-day-old newborns. This feature was seemingly the cause of low resistance of the larynx to colonization in newborn infants, which determined frequent colonization of their laryngeal mucosa with Staphylococcus aureus and Klebsiella.

[Microbial colonization and succession in the large intestine of newborn infants during their stay with mothers at the maternity hospital]. / Mikrobnaia kolonizatsiia i suktsessiia v tolstoi kishke u novorozhdennykh detei pri sovmestnom s mater'iu prebyvanii v rodil'nom dome.

Formation of microflora in the large intestine of 5-day old infants was studied in one of the Moscow maternity homes. The up-to-date procedures for isolation and identification of aerobic and anaerobic organisms were used in the study and the findings were processed on a computer. In the newborns of the maternity home of the "mother-infant" type there was observed colonization of the large intestine with aerobic and anaerobic organisms. A wave-like dynamics in the formation of the symbiotic microflora was revealed. It reflected the phenomenon of the microbial succession in the infants. The attempts to detect microbial interference between the species colonizing the large intestine showed that it was extremely rare in the 5-day old infants. This was likely the reason of the low intestine resistance to the colonization in the newborns which in its turn defined the frequent colonization of the intestine mucosa with S. aureus and the organisms of the Klebsiella, Enterobacter and Citrobacter group.

[Development of intestinal flora in neonates].

The development of faecal bacterial flora was studied using quantitative anaerobic and aerobic culture methods to determine the differences between various types of feeding. Enterobacteria first colonized predominantly in neonatal intestine, and their viable counts on the first day of life were between 10(8)-10(10) per gram faeces. In the breast-fed group, enterobacteria decreased gradually and their level on the 6th day of life was about 10(6) per gram faeces. Bifidobacteria began to increase after 2 or 3 days of life and outnumbered other bacteria, amounting to about 10(10) per gram faeces on the 6th day. In the bottle-fed group, enterobacteria maintained their high counts despite the increase of bifidobacteria, and their counts (10(9.3 +/- 1.1)/g) on the 6th day still exceeded those of bifidobacteria (10(8.4 +/- 1.6)/g). At 1 and 3 months of age, bifidobacteria were the most prevalent organisms in all feeding groups. However, the numbers of other bacteria such as enterobacteria were significantly greater in the bottle-fed infants than in the breast-fed infants. In the breast-fed formula supplemented group, bacterial colonization of the intestine was in the middle range between the breast-fed group and the bottle-fed group. In addition to the microbiological study, physicochemical properties of faeces and milk (i.e. pH and buffering capacity) were examined to explore their effects on the faecal bacterial flora. Faeces from breast-fed infants had a lower pH and lower buffering capacity than those from bottle-fed infants. The buffering capacity of formula was almost twice as much as that of human milk. It is postulated therefore, that low buffering capacity of human milk seems to produce an acidic environment in the intestine, which is favourable for the growth of bifidobacteria and unfavourable for the growth of potential pathogenic bacteria such as enterobacteria. These results suggest that breast feeding is beneficial for protection against intestinal and/or systemic infection.