Eleanor Dunlop¹, Nazheef Mohammed¹, Sally Appleton¹, Renu Vohra¹

¹Microbiology department, QML pathology, Murarrie, QLD, Australia. 

Capnocytophaga species are fastidious, Gram-negative bacteria associated with sepsis in immunocompromised patients. Capnocytophaga canimorsus and Capnocytophaga sputigena are the most frequently reported Capnocytophaga species in the literature of which C. canimorsus is part of the normal oral flora of animals and C. sputigena of humans ¹. 

In response to a recent increase in laboratory detection, a review of Capnocytophaga bacteraemias at QML was undertaken.

A retrospective audit of blood culture results with Capnocytophaga species reported over the past 5 years was performed. 

14 positive blood culture sets were identified representing 10 clinical cases of Capnocytophaga species infection. Of these, 8 were C. canimorsus, one C. sputigena and one was a novel Capnocytophaga species identified by 16s rRNA PCR and sequencing. The average time to positivity for C. canimorsus isolates was 84 hours (10 – 117 hours).

In 8 of the 10 cases, isolates were successfully identified with the use of MALDI-ToF MS. All isolates were susceptible to beta lactams and fluoroquinolones. 

Due to prolonged time to positivity, extending incubation time for potential zoonotic infections should be considered. Educating clinicians that turn-around-time for results may be extended for Capnocytophaga infections.

1.       Supavit Chesdachai, Don Bambino Geno Tai, Zachary A Yetmar, Anisha Misra, Natalie Ough, Omar Abu Saleh, The Characteristics of Capnocytophaga Infection: 10 Years of Experience, Open Forum Infectious Diseases, Volume 8, Issue 7, July 2021, ofab175, https://doi.org/10.1093/ofid/ofab175

Author contribution statement: We certify that all authors have contributed to this work.