Summary Klebsiella pneumoniae is the most clinically relevant species of this genus, known to cause both community-acquired and nosocomial infections worldwide. In the past two decades, a distinct ...hypervirulent strain of K pneumoniae , characterised by its hypermucoviscous phenotype, has emerged as a clinically significant pathogen responsible for highly invasive infections. We present a case of osteomyelitis due to hypervirulent K pneumoniae reported in the USA. Genomic testing of the K pneumoniae isolate was performed due to the striking clinical presentation of the infection as well as the hypermucoid nature of the isolates, raising the suspicion for possible infection with the hypervirulent strain. Whole-genome sequencing and additional PCR testing demonstrated the isolate to be a K1 serotype, sequence type 23 strain expressing rmpA and rmpA2 . Given the multiple reports of this pathogen causing invasive infections, clinicians should be aware of the possible presentation of metastatic and severe infection, including osteomyelitis, due to the hypervirulent strain of K pneumoniae not typical of classic K pneumoniae variants. In this Grand Round, we review the clinical features of hypervirulent K pneumoniae and its link to invasive infections, and discuss the need for improved awareness and identification of the pathogen.
The detection of blood stream infections is one of the most important functions of the clinical microbiology laboratory. Sepsis is a clinical emergency, and mortality increases if commencement of ...appropriate antimicrobial therapy is delayed. Automated blood culture systems are the most sensitive approach for detection of the causative agent of sepsis. Several laboratory methods have been developed to expedite identification of organisms directly from positive blood culture broth. The principle and analytical performance characteristics of these methods are described in this review.