low virulence organisms , normal flora of vagina or
obvious pathogens such as E.Coli, Mycoplasma, Ureaplasma
bacteria ascending from vagina, breaching cervical defenses (mucus plug etc.)
bacterial colonization of intrauterine space through intact or ruptured membranes
maternal and fetal acute inflammatory response,
clinically evident in 0.5-10% of pregnancies
|General Gross Description|
membranes and chorionic plate appear cloudy and occasionally have a yellow or green tint
in severe cases the umbilical cord may have small yellow round lesions on its surface which represent foci of PMN's (small abscesses)
|General Microscopic Description|
Chorioamnionitis: membranes (amnion and chorion + parietal decidua) show neutrophilic infiltrate. PMN's originate from maternal vessels in parietal decidua and migrate into chorion and then amnion.
Chorionitis: chorionic plate shows neutrophilic infiltrate. PMN's orginate from maternal intervillous space and migrate into subchorionic fibrin, chorion itself and then amnion
Funisitis: umbilical cord shows neutrophilic infiltrate. PMN's orginate in the fetal vessels of the umbilical cord and migrate sequentially through the muscular layers of the vessel and then into the Wharton's jelly.
Chorionic vasculitis: chorionic vessels show neutrophils in wall. PMN's originate in the fetal vessels of the chorionic plate and migrate through the walls of the fetal vessels toward the amniotic fluid
Gibbs and Sweet "Maternal and Fetal Infections" (chapter 42) in Creasy and Resnik, Maternal Fetal Medicine: Principles and Practices 3rd edition; Philadelphia: WB Saunders, 1994, p644-646.
This link will directly take you to the relevant new literature
||Synopsis by: Linda Ernst (T88260M41000)