1.A Case of Scratched Infection by Capnocytophaga canimorsus Diagnosed Early with Microscopic Peripheral Blood Smear Examination
Hiroko KAJIKAWA ; Mitsuyasu IKEDA ; Rina YAMAKAWA ; Kaori TOMARU ; Kouji IKEBE ; Kayoko YAMAMOTO ; Manani SASATANI ; Seishi MIZUNO ; Takashi FUJII ; Masaaki SAKURAYA ; Kenichi YOSHIDA
Journal of the Japanese Association of Rural Medicine 2016;65(4):843-849
Capnocytophaga canimorsus is a spindle-shaped facultatively anaerobic Gram-negative rod in the oral cavity of dogs and cats. C. canimorsus rarely infects humans through an animal bite or scratch. However, it leads to severe sepsis once infection occurs, and the fatality rate is estimated to be up to 30%. The patient was a 56-year-old man with fatigue and fever. Sepsis with thrombocytopenia was suspected from the blood examination results. We decided to conduct microscopic examination of a non-stained peripheral blood smear and identified bacteria; therefore, Gram stain was immediately performed and spindle-shaped Gram-negative bacilli were detected. Additionally, the patient had a history of a bite and scratch by his cat. We suspected C. canimorsus infection from the microscopic examination findings and history. Moreover, we determined early that the pathogenic bacterium was C. canimorsus by blood culture. With immediate and proper treatment based on these results, we could rescue this septic patient with disseminated intravascular coagulation. Microscopic examination of non-stained peripheral blood smear is helpful for the early diagnosis of C. canimorsus infection.