The Brief case: Misidentification of Cardiobacterium valvarum as Biosafety Level 3 organism Francisella tularensis by VITEK® automated system and diagnostic approach using a "rule out or refer" algorithm.
Stefan Schlabe, Galina Asseva, Nicolle Hertel et al.
✦ AI-curated · Sources linked
Case in brief
A bacterial isolate initially misidentified as Francisella tularensis by the VITEK® automated system was ultimately confirmed to be Cardiobacterium valvarum. The misidentification posed a significant challenge due to the potential implications of a BSL-3 organism. Clinical evaluation, culture, biochemical tests, and susceptibility testing led to the ruling out of F. tularensis, with final confirmation achieved through 16S rRNA sequencing.
Diagnostic / clinical pearl
Clinicians should remain cautious of automated identification systems, particularly when dealing with closely related or rare microorganisms, and consider traditional microbiological techniques alongside modern methods.
Why it matters
This case underscores the importance of a comprehensive diagnostic approach, especially when the potential for misidentification involves high-risk pathogens.