The Characteristics of Capnocytophaga Infection: 10 Years of Experience

Abstract

Background Capnocytophaga is a Gram-negative, facultative anaerobe. Human infection is rare but can lead to devastating outcomes. C. canimorsus can cause sepsis following an animal bite, whereas human-oral associated Capnocytophaga infections were reported in immunocompromised patients. Current data on these infections is not robust. Our goal is to provide a contemporary description of a unique characteristic of Capnocytophaga infections. Methods We performed a retrospective review of all patients with Capnocytophaga infection from January 2010 to August 2020 at three main hospitals of Mayo Clinic in Rochester, Minnesota, Scottsdale, Arizona, and Florida. We collected baseline demographic data, clinical characteristics, microbiological data, and outcomes of C. canimorsus and human-oral associated Capnocytophaga infection. Results Among 82 patients with Capnocytophaga infection, 46 patients (56.0%) had bacteremia. The most common species identified in this group was C. sputigena (57.9%), followed by C. canimorsus (34.8%). Patients with human-oral associated Capnocytophaga bacteremia were often immunocompromised, presented with neutropenic fever, and had worse six months all-cause mortality compared to C. canimorsus bacteremia (36.4% vs. 6.2%, p=.03). They also had a higher beta-lactamase production rate (36.4% vs. 0.0%, p=.02). Among patients without bacteremia, the main clinical syndrome was polymicrobial head and neck infections (47.2%). Conclusions Human-oral associated Capnocytophaga bacteremia occurs primarily in immunocompromised patients, particularly those with hematologic malignancy. In contrast, C. canimorsus bacteremia is more likely to present with community-onset infection related to zoonotic exposure. Human-oral associated Capnocytophaga infection without bacteremia is frequently isolated in polymicrobial infection; this phenomenon's significance is yet to be fully understood.

Meningitis caused by Capnocytophaga canimorsus in a COVID-19 patient: a rare complication of dog bites

“…Chesdachai et al . 1 found that meningitis associated with Capnocytophaga bacteremia primarily occurs in immunocompromised patients. Capnocytophaga infection may cause a life-threatening condition.…”

“…Capnocytophaga canimorsus is a fastidious, fermenter, capnophilic, facultative anaerobic, fusiform or filamentous gram-negative rod found in the commensal oral microbiota of dogs and cats 1 . It was first reported as a cause of meningitis and septicemia in the 1970s.…”

“…Transmission to humans may occur after a bite and rarely after dog/cat licking of pre-existing wounds 3 . Infections related to feline exposure are less frequent 1 , 2 , 4 . Most of the infections occur in men over the age of 50 with a history of dog bites and immunocompromise 2 , 3 .…”

Capnocytophaga canimorsus Bloodstream Infection Associated with an Urticarial Exanthem

“…Of the nearly 500 documented cases of C. canimorsus infection as of 2014, the fatality rate was approximately 6.2% to 26% [1,7,8]. A variety of clinical presentations have been described, with the most common being sepsis.…”

“…Other reported clinical presentations include meningitis, endocarditis, cellulitis, and eye infections [1]. Infections with the organism are typically treated with beta-lactam/beta-lactamase inhibitor, 3 rd /4 th generation cephalosporins, or carbapenems [6,7]. Our case illustrates a less common presentation of Capnocytophaga infection presenting with mild constitutional symptoms and an urticarial exanthem in a patient with history of a dog bite that occurred several weeks prior to the patient first seeking medical attention, diabetes, but no specific immunocompromising factors.…”