Chorioamnionitis (Chp. 26)

Prevalence of chorioamnionitis

1-5% of all pregnancies 50-70% of VLBW infants 80% of PPROM

Two types of chorioamnionitis

1. Acute chorioamnionitis 2. Subclinical chorioamnionitis

Management of the exposed chorioamnionitis infant

1. All receive full septic work up (even if they appear healthy) 2. All receive broad spectrum antibiotics until early-onset sepsis ruled out.

Neonatal complications associated with subclinical chorioamnionitis

1. Brain injury 2. Chronic lung disease 3. ROP 4. NEC

Obstetric management of chorioamnionitis

1. Broad-spectrum antibiotics for at least 24 hours 2. Prompt delivery of fetus 3. Antenatal steroids controversial

Neonatal complications associated with acute chorioamnionitis

1. Early-onset sepsis at birth 2. Respiratory distress 3. Cardiovascular instability

Microbes responsible for acute chorioamnionitis

1. GBS 2. E.Colo 3. Strep. viridans

Factors associated with development of clinical chorioamnionitis

1. Maternal colonization of GBS 2. GBS bacteriuria 3. Nulliparity 4. Internal monitoring devices 5. Meconium stained amniotic fluid 6. Serial vaginal exams 7. Increased duration of labor 8. Increased duration of ROM

Clinical chorioamnionitis diagnosis criteria

1. Maternal fever >100.4 PLUS (2) 1. Maternal leukocytosis 2. Maternal and fetal tachycardia 3. Uterine tenderness 4. Foul-smelling or purulent amniotic fluid

Microbes responsible for subclinical chorioamnionitis

1. Ureaplasma urealyticum 2. Mycoplamsa hominis 3. Gardneerella vaginalis

Most common organisms recovered in culture-proven chorioamnionitis?

1. Ureaplasma urealyticum 2. Mycoplasma hominis

How do microbes usually invade the intrauterine space?

Ascending through the cervix from lower genital tract.

How to identify microorganisms in amniotic fluid

Broad-range PCR

Potential sites of intra-amniotic infection

Chorio-decidual space, fetal membranes, placenta, amniotic fluid, umbilical cord, fetus

What antibiotics are contraindicated in maternal chorioamnionitis management?

Co-amoxiclav & erythromycin

Is clinical or histologic chorioamnionitis more common?

Histologic

Histologic chorioamnionitis

Inflammation of the chorion and amnion (placenta)

Chorioamnionitis

Intra-amniotic infection

What symptom can occur from placement of epidural

Maternal Fever (usually occurs within 4-6 hours)

Risk factors associated with chorioamnionitis

Maternal morbidity, preterm birth, early-onset neonatal sepsis, BPD, ROP, periventricular leukomalacia

Why is it difficult to identify women with chorioamnionitis?

Microbial invasion can be chronic and clinically silent.

Clinical chorioamnionitis

Term when characteristic clinical signs of chorioamnionitis are present