Table of Contents
Definition / general | Terminology | Epidemiology | Pathophysiology | Etiology | Clinical features | Radiology description | Prognostic factors | Case reports | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Electron microscopy descriptionCite this page: Kowalski PJ. Necrotizing funisitis. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/placentanecrotizingfun.html. Accessed January 24th, 2021.
Definition / general
- Definition: in long standing inflammatory processes, a fetal inflammatory response resulting in tissue necrosis and the accumulation of cellular debris that extends into the substance of the umbilical cord
Terminology
- Use of "funisitis" as a generic descriptor of inflammation without further comment as to its location (umbilical artery or vein, Wharton jelly, etc.) is generally discouraged
- Inflammation may be localized to umbilical vein (phlebitis) or umbilical arteries (arteritis)
- Inflammation at the periphery or surface of the umbilical cord may also be a primary pattern (peripheral funisitis), distinct from necrotizing funisitis
Epidemiology
- Not well documented but seen as a sequela in a minority of severe cases of chorioamnionitis or umbilical vasculitis
Pathophysiology
- Microorganisms gain access to the placenta or umbilical cord either by ascending from the endocervical canal, by the maternal bloodstream or by direct inoculation, such as from a diagnostic procedure
- In response, cytokines IL8, interferon gamma, complement components or leukotriene B4 are released by endothelium, mast cells and macrophages, creating a chemoattractant chemical gradient for neutrophils
- Chemical gradient may be augmented by certain peptides released by microorganisms
- Activated neutrophils marginate against the vascular endothelium and transmigrate through the vascular wall into the connective tissue of Wharton jelly
- Eventually, immune complexes from microbiologic antigens precipitate and elicit a maternal antibody response through the transplacental passage of antibodies
Etiology
- Due to various longer term infections involving a wide range of bacteria, viruses, fungi or parasites
- Classically described with congenital syphilis infection
Clinical features
- Typically seen in association with chorioamnionitis (maternal inflammatory response including fever, tachycardia, leukocytosis or foul smelling amniotic fluid)
Radiology description
- Inflammation induced calcifications within Wharton jelly can be distributed as a spiraled "barber's pole" on maternal radiographs
Prognostic factors
- More severe inflammatory response is seen when funisitis is present in preterm infants, possibly accounting for some differences in gestational age related morbidity (Hum Pathol 2001;32:623)
- Histopathologic severity may help predict certain neonatal outcomes (Placenta 2015;36:1490)
Case reports
- 24 year old woman with prolonged fetal bradycardia complicated by necrotizing funisitis (ISRN Obstet Gynecol 2011;2011:320246)
- 24 year old woman with necrotizing funisitis associated with Actinomyces meyeri infection (Pediatr Pathol 1994;14:927)
- Necrotizing funisitis and herpes simplex infection of placental and decidual tissue (Hum Pathol 1994;25:715)
Treatment
- Antibiotic therapy, particularly if symptoms of chorioamnionitis are present
Gross description
- Cut surface of an involved umbilical cord may show concentric circles or chalky calcified arcs surrounding one or more umbilical vessels, distributed in successive "waves"
- External surface of an involved umbilical cord is generally unremarkable unless accompanying peripheral funisitis is present
Microscopic (histologic) description
- Tissue necrosis and the progressive accumulation of inflammatory cells, cellular debris and fluid into the umbilical cord substance
Microscopic (histologic) images
Electron microscopy description
- Necrotic debris and inflammation can be seen surrounding one or more umbilical vessels, often appearing as concentric "waves"
- Presence of immune complexes aggregated as arcs around vessels are analogous to the precipitin arcs seen in an Ouchterlony immunodiffusion assay
- Calcification of the immune complexes or cellular debris can be partially or entirely encircling the vessel(s)