Chorioamnionitis
Encyclopedia
Chorioamnionitis is an inflammation
of the fetal membranes (amnion
and chorion
) due to a bacteria
l infection
. It typically results from bacteria ascending into the uterus from the vagina and is most often associated with prolonged labour
. Risk of developing chorioamnionitis increases with each vaginal exam during final month of pregnancy and during labor.[3]
Exclusions:
examination of the fetal membranes.
Infiltration of the chorionic plate by neutrophils is diagnostic of (mild) chorioamnionitis. More severe chorioamnionitis involves subamniotic tissue and may have fetal membrane necrosis
and/or abscess
formation.
Severe chorioamnionitis may be accompanied by vasculitis
of the umbilical vessels (due to the fetus' inflammatory cells) and, if very severe, funisitis (inflammation of the umbilical cord's connective tissue).
and cerebral palsy
.
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
of the fetal membranes (amnion
Amnion
The amnion is a membrane building the amniotic sac that surrounds and protects an embryo. It is developed in reptiles, birds, and mammals, which are hence called “Amniota”; but not in amphibians and fish , which are consequently termed “Anamniota”. The primary role of this is the protection of the...
and chorion
Chorion
The chorion is one of the membranes that exist during pregnancy between the developing fetus and mother. It is formed by extraembryonic mesoderm and the two layers of trophoblast and surrounds the embryo and other membranes...
) due to a bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
l infection
Infection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
. It typically results from bacteria ascending into the uterus from the vagina and is most often associated with prolonged labour
Childbirth
Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
. Risk of developing chorioamnionitis increases with each vaginal exam during final month of pregnancy and during labor.[3]
Background
The fetal membranes consist of two parts:- The outer membrane is the chorionChorionThe chorion is one of the membranes that exist during pregnancy between the developing fetus and mother. It is formed by extraembryonic mesoderm and the two layers of trophoblast and surrounds the embryo and other membranes...
. It is closest to the mother and physically supports the much thinner amnion. - The inner membrane is the amnionAmnionThe amnion is a membrane building the amniotic sac that surrounds and protects an embryo. It is developed in reptiles, birds, and mammals, which are hence called “Amniota”; but not in amphibians and fish , which are consequently termed “Anamniota”. The primary role of this is the protection of the...
. It is in direct contact with the amniotic fluidAmniotic fluidAmniotic fluid or liquor amnii is the nourishing and protecting liquid contained by the amniotic sac of a pregnant woman.- Development of amniotic fluid :...
, which surrounds the fetusFetusA fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
.
Diagnosis
Clinical
Chorioamnionitis is diagnosed clinically in the setting of:- maternal feverFeverFever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
. - uterineUterusThe uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...
tendernessTendernessTenderness can mean:* a tendency to express warm, compassionate, or affectionate feelings* delicate or intimate physical contact* tenderness – pain or discomfort when an affected area is touched-Other:...
in the presence of confirmed premature rupture of membranes (PROM).
Exclusions:
- maternal upper respiratory infection.
- maternal urinary tract infectionUrinary tract infectionA urinary tract infection is a bacterial infection that affects any part of the urinary tract. Symptoms include frequent feeling and/or need to urinate, pain during urination, and cloudy urine. The main causal agent is Escherichia coli...
.
Pathologic
Chorioamnionitis can be diagnosed from a histologicHistology
Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...
examination of the fetal membranes.
Infiltration of the chorionic plate by neutrophils is diagnostic of (mild) chorioamnionitis. More severe chorioamnionitis involves subamniotic tissue and may have fetal membrane necrosis
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
and/or abscess
Abscess
An abscess is a collection of pus that has accumulated in a cavity formed by the tissue in which the pus resides due to an infectious process or other foreign materials...
formation.
Severe chorioamnionitis may be accompanied by vasculitis
Vasculitis
Vasculitis refers to a heterogeneous group of disorders that are characterized by inflammatory destruction of blood vessels. Both arteries and veins are affected. Lymphangitis is sometimes considered a type of vasculitis...
of the umbilical vessels (due to the fetus' inflammatory cells) and, if very severe, funisitis (inflammation of the umbilical cord's connective tissue).
Treatment
Treatment consists of:- antibiotics (amoxicillinAmoxicillinAmoxicillin , formerly amoxycillin , and abbreviated amox, is a moderate-spectrum, bacteriolytic, β-lactam antibiotic used to treat bacterial infections caused by susceptible microorganisms. It is usually the drug of choice within the class because it is better absorbed, following oral...
+ gentamicinGentamicinGentamicin is an aminoglycoside antibiotic, used to treat many types of bacterial infections, particularly those caused by Gram-negative organisms. However, gentamicin is not used for Neisseria gonorrhoeae, Neisseria meningitidis or Legionella pneumophila...
+ metronidazoleMetronidazoleMetronidazole is a nitroimidazole antibiotic medication used particularly for anaerobic bacteria and protozoa. Metronidazole is an antibiotic, amebicide, and antiprotozoal....
) for the mother, and - quickly delivering the baby.
Associations
Chorioamnionitis is a risk factor for periventricular leukomalaciaPeriventricular leukomalacia
Periventricular leukomalacia is a form of white-matter brain injury, characterized by the necrosis of white matter near the lateral ventricles. It can affect newborns and fetuses; premature infants are at the greatest risk of the disorder...
and cerebral palsy
Cerebral palsy
Cerebral palsy is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement....
.
External links
- Overview at Cleveland ClinicCleveland ClinicThe Cleveland Clinic is a multispecialty academic medical center located in Cleveland, Ohio, United States. The Cleveland Clinic is currently regarded as one of the top 4 hospitals in the United States as rated by U.S. News & World Report...
. - Cerebral palsy inflammation link (29 November 2003) at BBCBBCThe British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
.