Capnocytophaga infection

Capnocytophaga infection is a bacterial infection transmitted by a dog or cat bite/scratch. Risk factors for infection are prior splenectomy, alcoholism, and other causes of impaired immunity. Cellulitis may be followed by septicemia after the lick, bite, or scratch of an infected cat or dog.

CASES/YEAR
225 (US); 4,500 (Global)
CATEGORY
Zoonoses
AGENT TYPE
Bacteria
OTHER NAMES
Dysgonic fermenter-2 infection; DF-2 infection; Capnocytophaga canimorsus infection;
ACUITY
Acute-Moderate
INCUBATION
1-5 days
INITIAL SYMPTOMS
Cellulitis of wound from dog or cat bite/scratch followed by fever and sepsis;
PRECAUTIONS
COMMENTS
Risk factors for infection are prior splenectomy, alcoholism, and other causes of impaired immunity. Cellulitis may be followed by septicemia after the lick, bite, or scratch of an infected cat or dog. Meningitis, endocarditis, and septic arthritis have also been reported. Patients may develop a rash, thrombocytopenia, petechiae, acute renal failure, disseminated intravascular coagulation, gangrene, and shock. [ID, p. 58, p. 1755] Sepsis and meningitis are the most common presentations. The case-fatality rate for septicemia is 13% to 33%, but rates as high as 60% to 80% have been reported in patients with septic shock and organ failure. Other complications are hemolytic uremic syndrome, glomerulonephritis, acute renal failure, and pneumonia. [PPID, p. 2820] Endocarditis is rare. [ABX Guide]
DIAGNOSTIC
Presumptive dx: filamentous Gram negative rods on stain of blood smear or buffy coat; Slowly growing microbes that require 5% to 10% CO2; [PPID, p. 2820-1]
SCOPE
Global
SIGNS & SYMPTOMS
  • >fever
  • H thrombocytopenia
  • S cellulitis or rash, circinate
  • S petechiae and ecchymoses
  • S rash (exanthem)
  • S urticaria
  • X lung infiltrates
  • X pleural effusions
  • *acute renal failure
  • *arthritis
  • *bleeding tendency
  • *endocarditis
  • *glomerulonephritis
  • *meningitis
  • *osteomyelitis
  • *peripheral neuropathy
  • *pneumonia
  • *sepsis
  • *shock
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Animal Bite
RESERVOIR
Cats, Dogs
RISK FACTORS
  • Asplenic patients
  • Handle dog or cat (bite or scratch)
DRUG LINK
Merck Manual: Human and Mammal Bites
REFERENCES FOR CASES/YEAR
1. (US) There are about 1 million dog bites in the US every year, and C canimorsus is the main human pathogen isolated. "We reviewed clinical and epidemiologic features of 56 human Capnocytophaga canimorsus isolates submitted during a 32-year period to California's Microbial Diseases Laboratory for identification." [CDC: EID Journal. Feb. 2006] Estimated 150-300 cases/year in the US; [PPID, p. 2820]
2. (Global) Guesstimate: global cases/yr = 20 X US cases/yr.