Aim-To serially characterise aerobic and anaerobic stool microflora in extremely low birthweight infants and to correlate colonisation patterns with clinical risk factors. Methods-Stool specimens from 29 infants of birthweight <1000 g were collected on days 10, 20, and 30 after birth. Quantitative aerobic and anaerobic cultures were performed. Results-By day 30, predominant species were Enterococcus faecalis, Escherichia coli, Staphylococcus epidermidis, Enterbacter cloacae, Klebsiella pneumoniae, and Staphylococcus haemolyticus. Lactobacillus and Bifidobacteria spp were identified in only one infant. In breast milk fed (but not in formula fed) infants, the total number of bacterial species/stool specimen increased significantly with time (2.50 (SE 0.34) on day 10; 3.13 (0.38) on day 20; 4.27 (0.45) on day 30) as did quantitative bacterial counts; Gram negative species accounted for most of the increase. On day 30, significant inverse correlations were found between days of previous antibiotic treatment and number of bacterial species (r=0.491) and total organisms/g of stool (r=0.482). Gestational age, birthweight, maternal antibiotic or steroid treatment, prolonged rupture of the membranes, and mode of delivery did not seem to aVect colonisation patterns. Conclusions-The gut of extremely low birthweight infants is colonised by a paucity of bacterial species. Breast milking and reduction of antibiotic exposure are critical to increasing fecal microbial diversity.

No abstract

OBJECTIVE:To determine the effects of repeated application of an occlusive ointment on the skin of very low birth weight infants. STUDY DESIGN:Nineteen neonates of 26 to 30 weeks gestational age were randomly assigned to receive topical Aquaphor ointment twice daily for 2 weeks or to receive standard skin care. Skin quality, fluid requirements, and skin bacterial colonization counts were assessed. RESULTS:Infants treated with Aquaphor had significantly improved skin condition scores versus controls (p ϭ 0.002). Aquaphor improved skin scores over time (p ϭ 0.012) in treated infants, whereas skin scores of untreated infants worsened before eventually healing. There were no significant differences in total fluid requirements, urine output, serum sodium concentrations, skin bacterial counts, fungal counts, or colonization patterns between treated and control infants in either gestational age cohort. CONCLUSION:Aquaphor ointment, used during the first two postnatal weeks, improved skin condition in infants of 26 to 30 weeks' gestation without changing skin bacterial flora. We speculate that improved skin condition may limit transepidermal water loss and decrease portals of entry for pathogens, thereby potentially decreasing fluid and electrolyte imbalances and sepsis in very low birth weight infants.Neonatal intensive care unit (NICU) providers are continually challenged by the task of providing skin care to the very low birth weight (VLBW) infant. Intact skin is the premature infant's principal barrier to infection, absorption of chemicals, and fluid loss. 1 Skin permeability is inversely proportional to the degree of prematurity. 1 Increased skin permeability predisposes the VLBW infant to increased transepidermal water loss (TEWL), to absorption of commonly used topical agents such as povidone-iodine and alcohol, and to mechanical and thermal injury and infection. 2 The large ratio of surface area to body weight, in conjunction with an immature stratum corneum, compounds TEWL. 3 Increased TEWL can, in turn, result in clinically significant fluid and electrolyte imbalances in the first postnatal days.VLBW infants are prone to skin breakdown as a result of accidental epidermal stripping. Skin breakdown can augment the rate of TEWL, while providing a portal of entry for microorganisms that can lead to bacteremia. Infants born at Ͻ28 weeks' gestation, or with birth weight of Ͻ1000 gm, and aged Ͻ2 postnatal weeks old are at greatest risk for iatrogenic complications related to the integrity of their skin.Most NICU guidelines for the care of the skin of the VLBW infant are based on empirical or anecdotal data. There are several studies that measure efforts to decrease TEWL. These studies include the use of paraffin wax wraps, 3,4 plastic blankets, 3,5 humidity, 6 and artificial skin barriers. 7-9 All these methods have been shown to reduce TEWL. There have been few studies regarding the safe use of emollient therapy for this at-risk population, and most of the infants studied have been of Ͼ30 weeks' gestation. 10,11 Acc...

Clostridium difficile, the primary cause of nosocomial diarrhea in the United States and many other industrialized countries, is recognized as a major health concern because of its ability to cause severe intestinal disease leading to complications such as relapses and infections due to vancomycin-resistant enterococci. The disease results from two toxins, toxins A and B, produced by this pathogen. In this study, we evaluated the TOX A/B TEST, a new 1-h enzyme immunoassay (EIA) that detects toxins A and B. We compared the test with the tissue culture assay, which is recognized as the “gold standard” forC. difficile testing. Evaluations were performed in-house at TechLab, Inc. (Blacksburg, Va.) and off-site at four clinical laboratories. Of 1,152 specimens tested, 165 were positive by the TOX A/B TEST and tissue culture and 973 were negative by both tests. The sensitivity and specificity were 92.2 and 100%, respectively. The positive and negative predictive values were 100 and 98.6%, respectively, and the correlation of the TOX A/B TEST with tissue culture was 98.8%. When discrepant samples were resolved by culture, the sensitivity and specificity were 93.2 and 98.9%, respectively. The positive and negative predictive values were 100 and 98.8%, respectively, with a correlation of 99.0%. There were no specimens that were positive by the TOX A/B TEST and negative by tissue culture. Fourteen specimens were negative by the TOX A/B TEST but positive by tissue culture. Of these, two were negative by toxigenic culture, five were positive by toxigenic culture, and seven were not available for further testing. There were no indeterminate results, since the test does not have an indeterminant zone. In a separate study, 102 specimens that were positive by tissue culture and the TOX A/B TEST were examined in toxin A-specific EIAs. Two specimens that presumptively contained toxin A-negative, toxin B-positive (toxA−/toxB+) isolates were identified. One specimen was from a patient with a clinical history consistent with C. difficile infection. Isolates obtained from these specimens by selective culture on solid media and in broth tested toxA−/toxB+ when grown in brain heart infusion dialysis flasks, which stimulate in vitro production of both toxins. Our findings show that the TOX A/B TEST is suitable as a diagnostic aid for C. difficile disease because it correlates well with tissue culture and detects isolates that may be missed with toxin A-specific EIAs.

The protein II (P.11) outer membrane proteins of Neisseria gonorrhoeae, which have been implicated in gonococcal pathogenesis, have been previously shown to undergo a type of phase variation in which expression of any of several different forms of the proteins may be switched on or off. We identified six electrophoretically distinct forms of P.11 proteins (designated P.IIa through P.11f) within strain FA1090, and we isolated colonial variants of FA1090 that expressed only one of the six different P.11 protein forms. Two monoclonal antibodies that bound specifically and differentially to P.11 proteins were produced. One antibody bound to proteins P.IIb and P.Ild and was bactericidal for all colonial variants expressing P.IIb. The second antibody bound to P.IIa and was bactericidal for colonial variants expressing P.IIa. P.JI protein profiles of survivors of antibody killing indicated that multiple P.11 protein species may be expressed on a single bacterium and that P.11 protein switching in the gonococcus is nonrandom. 453 on August 5, 2020 by guest http://iai.asm.org/ Downloaded fromImmun. 31:965-970.