Exposure to domestic cats: risk factor for Pasteurella multocida peritonitis in liver cirrhosis?

Pasteurella multocida is most commonly associated with acute skin and soft tissue infections following an animal bite or scratch. Peritonitis caused by P. multocida in patients with cirrhosis is rarely reported. We present a case of spontaneous bacterial peritonitis with P. multocida in a patient with cirrhosis, squamous cell cancer of the head and neck, and nontraumatic domestic cat exposure. Nasopharyngeal colonization with P. multocida, with subsequent transient bacteremia and seeding of the peritoneum in immunocompromised (particularly cirrhotic) cat-owners, could play an important pathogenetic role in the development of spontaneous bacterial peritonitis. A review of the literature showed that in nine of 13 patients with cirrhosis and P. multocida peritonitis, exposure to domestic animals was reported. The mortality rate is high in this setting, even with prompt antibiotic treatment. Preventive strategies for immuno-compromised patients should include minimization of animal contact, especially cats, which have a high carriage rate (70-90%) of P. multocida.