[A fatal septic shock due to Capnocytophaga canimorsus and review of literature]

The Great pretender: the first case of septic shock due to Capnocytophaga canimorsus in Sardinia. A Case report and review of the literature

Capnocytophaga canimorsus (C. canimorsus) is an emerging pathogen in critical care. C. canimorsus is a Gram-negative bacillus, commonly isolated as a commensal microorganism of the oral flora of healthy dogs and cats. A 63-year-old woman came to the emergency department with fever, chills, and malaise 2 days after a minor dog bite. After admission to the medicine ward, she developed respiratory failure and livedo reticularis. In the intensive care unit (ICU), she presented full-blown septic shock with thrombocytopenia, coagulopathy, severe acute kidney injury, and liver injury. We describe the first case of septic shock with Multiple Organ Dysfunction Syndrome related to Capnocytophaga canimorsus infection in Sardinia and its treatment in a tertiary hospital ICU. We also review recent literature on the relevance of C. canimorsus in human disease and critical illness.

[Capnocytophaga spp. peritonitis in a peritoneal dialysis: A case report]

INTRODUCTION

Capnocytophaga spp. is a slow-growing bacterium that forms a part of the normal oral flora of dogs and cats. In peritoneal dialysis, only seven cases have been reported. We report the observation of a case of peritonitis with Capnocytophaga spp. in a patient on peritoneal dialysis who lives with a cat.

CASE REPORT

A 64-year-old woman with chronic end stage renal disease due to chronic interstitial nephropathy on automated peritoneal dialysis has been admitted for diffuse abdominal pain. The dialysis fluid was cloudy with 11,250 elements/mm³, of leukocytes. Direct examination was negative. The C-reactive protein was 165mg/L. Intraperitoneal probabilistic antibiotic therapy was initiated 1g of cefazolin and 1g of ceftazidime per day. After eight days, aerobic culture was negative, the anaerobic one was positive to gram negative bacilli, but the identification could not be possible with MALDI-TOF mass spectrometry. Antibiotic therapy was continued by ceftazidime for 21 days. The evolution was marked by the improvement of the clinical and biological state of the patient. The germ was finally identified using the genomic 16S rRNA sequencing technique. This is Capnocytophaga spp. Investigation then revealed that the patient's cat sometimes entered her room at the time of connection of peritoneal dialysis.

CONCLUSION

The case of our patient once again reveals the diagnostic difficulties posed by Capnocytophaga spp. Innovative techniques, such as MALDI-TOF-MS or genomic sequencing of ribosomal RNA, should be further used in peritoneal dialysis in the diagnosis of peritonitis.

Capnocytophaga canimorsus - a potent pathogen in immunocompetent humans - systematic review and retrospective observational study of case reports

Purpose: Severe and fatal Capnocytophaga canimorsus infection has been described in immunocompromised patients. Data of C. canimorsus infection in immunocompetent and risk factors of severe courses are missing. Our aims were to describe the epidemiology of C. canimorsus infection and to identify potential risk factors of sepsis and fatal outcome.Methods: Observational study and systematic review of all cases reported in immunocompetent subjects between 2002 and 2019.Results: A total of 128 cases of C. canimorsus infection in immunocompetent individuals were reported. Male gender comprised 74.2%, the median age was 58 years and 47.7% were admitted with sepsis. Case-fatality rate was 29.7% and especially high in septic patients (55.7%). Transmission by bite (OR = 2.37, 95% CI: 1.05-6.52) and incubation time ≤3 d (OR = 7.98; 95% CI: 2.33-27.34) were identified as risk factors of sepsis on admission, and early wound cleansing as protective (OR = 0.42; 95% CI: 0.14-0.96). Sepsis (OR = 23.67; 95% CI: 2.85-197.89) and septic shock (OR = 45.50; 95% CI: 3.08-676.55) were risk factors of fatal outcome, whereas early wound cleansing (OR = 0.05; 95% CI: 0.01-0.72), initial penicillin therapy with beta-lactamase inhibitors (OR = 0.48; 95% CI: 0.16-0.92) and surgical removal of infectious focus (OR = 0.38; 95% CI: 0.06-0.95) were protective factors.Conclusions: Immunocompetent patients with C. canimorsus infection frequently develop sepsis. A shorter incubation period in cases of sepsis might be related to higher infectious dose. Fatal outcome may be prevented by early wound cleansing, initial use of penicillins in combination with beta-lactamase inhibitors and surgical removal of an infectious focus.

Being Licked by a Dog Can Be Fatal: Capnocytophaga canimorsus Sepsis with Purpura Fulminans in an Immunocompetent Man

Bite infections caused by Capnocytophaga canimorsus are rare. Severe and fatal infections are more frequently reported in patients with immunodeficiency, splenectomy or alcohol abuse. We describe the case of a 63-year-old man who developed flu-like symptoms and presented after some delay with severe sepsis and purpura fulminans. He was found to be infected with C. canimorsus without a bite injury and did not demonstrate immunodeficiency or any other typical predisposition. Despite extensive intensive care, his conditions deteriorated and he died from multiorgan failure.