Ability of normal vaginal flora to produce detectable phosphatidylglycerol in amniotic fluid in vitro.
OBJECTIVE
To determine if bacteria are capable of producing phosphatidylglycerol in amniotic fluid (AF) and the number of colony forming units (CFU) of bacteria necessary to produce this result.


METHODS
Eleven species of bacteria and one species of yeast, common to the female genital tract and implicated in chorioamnionitis, were selected. Amniotic fluid was collected from 21 women and inoculated with 10(8) CFU/mL of each isolate. Aliquots of AF were tested at 0, 4, 12, and 24 hours for colony counts and the presence of phosphatidylglycerol by thin-layer chromatography.


RESULTS
The mean gestational age (+/- standard deviation) of the 21 study patients was 33 weeks and 1 day (+/- 4 weeks). Among the 12 species studied, Escherichia coli produced phosphatidylglycerol, at a concentration of 1.75 x 10(8) CFU/mL, beginning 12 hours after incubation.


CONCLUSIONS
Escherichia coli is capable of producing phosphatidylglycerol in AF in vitro and is present in the vagina in 24% of normal pregnant patients. Our findings question the validity of using vaginal pool AF specimens for phosphatidylglycerol determination. Therefore, we recommend that patients presenting with preterm premature rupture of membranes be evaluated by amniocentesis to determine fetal lung maturity with phosphatidylglycerol and the lecithin-sphingomyelin ratio.
Lambers
D S
DS
Department of Obstetrics and Gynecology, Good Samaritan Hospital, Cincinnati, Ohio, USA.
Brady
K
K
Leist
P A
PA
Setser
C
C
Helmchen
R
R
D000653:Amniotic Fluid / Q000737:chemistry*; D002821:Chorioamnionitis / Q000382:microbiology*; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000378:metabolism*; D005260:Female; D005865:Gestational Age; D006801:Humans; D066298:In Vitro Techniques; D010715:Phosphatidylglycerols / Q000032:analysis / Q000378:metabolism*; D011247:Pregnancy; D013292:Streptococcus agalactiae / Q000378:metabolism; D013997:Time Factors; D014621:Vagina / Q000382:microbiology*
D010715:Phosphatidylglycerols