Fatal Dog Bite in the Absence of Significant Trauma

Abstract

Sudden and unexpected nontraumatic death in individuals with asplenia or hyposplenia is usually due to fulminant bacterial sepsis, most often involving Streptococcus pneumoniae, Neisseria meningitidis, and Hemophilus influenzae. We report a case of a previously well 40-year-old man who died 5 hours after hospital admission. At autopsy Waterhouse-Friderichsen syndrome was identified and Capnocytophaga canimorsus was subsequently isolated on antemortem blood cultures. Infection of humans with this organism is most often due to dog bite or contact. Upon specific inquiry it was ascertained that 2 days before admission the deceased had suffered a superficial bite to his hand by his pet Staffordshire Bullterrier dog. His relevant history included a previous splenectomy following blunt abdominal trauma. Asplenia and hyposplenia at autopsy should prompt microbiological testing with consideration of unusual organisms such as C. canimorsus. Although histories of animal contact or injury are often not available at the time of autopsy, this should also be considered in cases of apparent fulminant sepsis. In individuals with asplenia or hyposplenia, dog bites do not have to involve excessive tissue trauma, vascular compromise, or blood loss to be lethal.

Unexpected death involving the spleen – an overview

“…28 Following splenectomy unusual bacterial causes of sepsis such as Capnocytophaga canimorsus may be lethal. 29 Other bacterial causes of splenic rupture include Clostridium perfringens with gas gangrene 30 as well as Salmonella paratyphi 31 and non-typhoid Salmonella. 32 Splenic abscesses may predispose to rupture and if found at autopsy should initiate a careful search for evidence of Reported examples have included a 15-year-old girl with embolized mitral valve vegetations that led to fatal rupture of a Haemophilus parainfluenzae splenic abscess, and a middle aged woman with Streptococcus mitis.…”

“…28 Following splenectomy unusual bacterial causes of sepsis such as Capnocytophaga canimorsus may be lethal. 29 Other bacterial causes of splenic rupture include Clostridium perfringens with gas gangrene 30 as well as Salmonella paratyphi 31 and non-typhoid Salmonella. 32…”

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

“…In the period 1990–2022, 125 articles described 207 cases of C. canimorsus infection (Supplemental Table). 12 …”

Bite Injuries to the Hand: Microbiology, Virology and Management

“…A rarer anaerobic gram-negative rod, Capnocytophaga canimorsus , is present in cat and dog mouth flora and has been seen to cause bacteraemia and sepsis, as well as unexpected death, particularly in the immunocompromised (including asplenia), and should be considered if a fever is present [17, 49-51] Bites involving salt or fresh water species, and even contamination with these solutions, have been shown to grow Mycobacterium species, particularly Mycoplasma marinum [52, 53]. Streptobacillicus moniliformis causes rat bite fever, more commonly seen in Asia, but related to rodent bites including squirrels, ferrets and mice.…”