Stool microflora in extremely low birthweight infants.
OBJECTIVE
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 affect 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.
Gewolb
I H
IH
Division of Neonatology-UMMS Rm N5W68, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD 21201-1554, USA. igewolb@peds05.ab.umd.edu
Schwalbe
R S
RS
Taciak
V L
VL
Harrison
T S
TS
Panigrahi
P
P
D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D001420:Bacteria, Aerobic / Q000302:isolation & purification*; D001421:Bacteria, Anaerobic / Q000302:isolation & purification*; D001644:Bifidobacterium / Q000302:isolation & purification; D001903:Bottle Feeding; D001942:Breast Feeding; D015331:Cohort Studies; D016972:Enterobacter cloacae / Q000302:isolation & purification; D013293:Enterococcus faecalis / Q000302:isolation & purification; D004926:Escherichia coli / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology*; D006801:Humans; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D007711:Klebsiella pneumoniae / Q000302:isolation & purification; D007778:Lactobacillus / Q000302:isolation & purification; D013210:Staphylococcus / Q000302:isolation & purification; D013212:Staphylococcus epidermidis / Q000302:isolation & purification
D000900:Anti-Bacterial Agents