Rapid, Simultaneous Detection of Clostridium sordellii and Clostridium perfringens in Archived Tissues by a Novel PCR-Based Microsphere Assay : Diagnostic Implications for Pregnancy-Associated Toxic Shock Syndrome Cases

Abstract EN

Clostridium sordellii and Clostridium perfringens are infrequent human pathogens; however, the case-fatality rates for the infections are very high, particularly in obstetric C.

sordellii infections (>90%).

Deaths from Clostridium sordellii and Clostridium perfringens toxic shock (CTS) are sudden, and diagnosis is often challenging.

Formalin-fixed, paraffin-embedded (FFPE) tissues usually are the only specimens available for sudden fatal cases, and immunohistochemistry (IHC) for Clostridia is generally performed but it cannot identify species.

A clear need exists for a rapid, species-specific diagnostic assay for FFPE tissues.

We developed a duplex PCR-based microsphere assay for simultaneous detection of C.

sordellii and C.

perfringens and evaluated DNA extracted from 42 Clostridium isolates and FFPE tissues of 28 patients with toxic shock/endometritis (20 CTS, 8 non-CTS, as confirmed by PCR and sequencing).

The microsphere assay correctly identified C.

sordellii and C.

perfringens in all known isolates and in all CTS patients (10 C.

sordellii, 8 C.

perfringens, 2 both) and showed 100% concordance with PCR and sequencing results.

The microsphere assay is a rapid, specific, and cost-effective method for the diagnosis of CTS and offers the advantage of simultaneous testing for C.

sordellii and C.

perfringens in FFPE tissues using a limited amount of DNA.