Necrotizing funisitis associated with Ureaplasma urealyticum infection: A clinicopathologic analysis of 14 cases

Abstract

Introduction: Necrotizing funisitis is a distinct lesion of the umbilical cord associated with chorioamnionitis and bloodborne fetal infection. The lesion may be a response to microorganisms in Wharton's jelly. A common microorganism detected in chorioamnionitis is Ureaplasma urealyticum (U. urealyticum). This study hypothesizes that U. urealyticum DNA will be present in Wharton's jelly in necrotizing funisitis.

Methods: Necrotizing funisitis was identified retrospectively from a 2-year pathology database and confirmed in review. Paraffin fixed embedded tissue sections of the lesion were prepared for polymerase chain reaction (PCR) by using primers to identify U. urealyticum. Twenty matched controls without funisitis were similarly processed. Clinical data included serological tests of common bloodborne infections in the mothers and infants, and U. urealyticum PCR results in the urine of the neonates.

Results: Fourteen cases of necrotizing funisitis were identified in 7,416 examined placentas. Nine of these umbilical cords were positive by PCR for U. urealyticum (64.3%). Nineteen of twenty control cases were negative. Eight of ten neonates (80%) also had positive urine PCR tests for U. urealyticum. No infants or mothers had evidence of bloodborne fetal infection.

Discussion: U. urealyticum DNA was present in Wharton's jelly by PCR testing in the majority of the necrotizing funisitis lesions tested. This result supports a possible causative role for U. urealyticum in many cases of necrotizing funisitis.

Keywords: Necrotizing funisitis; Placenta; Polymerase chain reaction; Preterm birth; Ureaplasma urealyticum.