Cirrhosis, cellulitis and cats: a 'purrfect' combination for life-threatening spontaneous bacterial peritonitis from Pasteurella multocida

Pasteurella Multocida Infection in Humans

Pasteurella multocida (P. multocida) is an immobile, anaerobic, Gram-negative coccobacillus fermenting bacterium. This pathogen is commonly prevalent in the upper airways of healthy pets, such as cats and dogs, but was also confirmed in domestic cattle, rabbits, pigs, birds, and various wild animals. Infection in humans occurs as a result of biting, scratching, or licking by animals and contact with nasopharyngeal secretions. Inflammation at the site of infection develops within the first day from the injury. It is usually confined to the skin and subcutaneous tissue but, in particular situations, may spread to other organs and manifest as a severe systemic infection. Careful history-taking and microbiological confirmation of the infection enable diagnosis and appropriate treatment. Any wound resulting from an animal bite should be disinfected. The preferred and highly effective treatment against local P. multocida infection is penicillin or its derivatives. The prognosis for P. multocida infections depends on the infected site and the patient's comorbidities.

Disseminated Pasteurella multocida in a patient with liver cirrhosis and spontaneous bacterial peritonitis – The role of cirrhosis-associated immune dysfunction

Disseminated Pasteurella multocida infection is rare and usually occurs in patients who are immunocompromised. Patients with liver cirrhosis seem to be particularly vulnerable; potentially related to cirrhosis associated immune dysfunction syndrome, frequently present in this population. While many patients report pet cat or dog bites or scratches, some patients develop infection even without obvious exposure, just from being in contact with animals. We present a patient with cellulitis and spontaneous bacterial peritonitis by Pasteurella multocida in whom infection disseminated and the patient developed bacteremia that seeded in the right acromioclavicular joint. We hypothesize that the port of entry for infection in our patient was contact with a pet cat through a chronic open leg wound. The patient was treated with intravenous ceftriaxone 2 g daily for 6 weeks and attained complete recovery.

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Pasteurella multocida is an opportunistic pathogen in immunocompromised patients.

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Pasteurella multocida must be suspected in any infection from an animal exposure.

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Liver cirrhosis patients are at risk due to cirrhosis-associated immune dysfunction.

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Spontaneous bacterial peritonitis is a rare complication of Pasteurella multocida.

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Liver cirrhosis or immunosuppressed patients with pets at home are at increased risk.

Amoxicillin-tolerant Pasteurella multocida strain isolated from chronic dermohypodermitis after suboptimal exposure to amoxicillin is not associated with reduced growth rate

Pasteurella multocida is rarely observed in human chronic infections. A Pasteurella multocida strain was isolated from a skin biopsy of chronic dermohypodermitis in a 21-year-old woman without an immunocompromised state. As this strain was viable one month after a cat scratch despite treatment by amoxicillin-clavulanic acid, we compared this strain's growth rate, amoxicillin Minimal Inhibitory and Bactericidal Concentrations (MIC and MBC), resistance to serum and ability to activate neutrophil granulocytes with those of control strains isolated during acute infections in humans without previous antibiotics exposure. This particular strain was not more resistant to serum and did not induce a lower phagocytic activity than control strains. It did not grow more slowly than control strains even after suboptimal exposure to amoxicillin. This particular strain was tolerant to amoxicillin but tolerance did not appear sufficient alone for the induction of a chronic infection in a host without an immunocompromised state.

Pasteurella multocida Bacteremia and Peritonitis in a Patient With Cirrhosis: A Life-Threatening Case From a Prick of a Cactus

A 58-year-old male with nonalcoholic steatohepatitis cirrhosis presents with right lower extremity cellulitis, abdominal tenderness, and severe sepsis after sustaining puncture injury from a cactus on a property with feral cats. Blood cultures and diagnostic paracentesis were consistent with spontaneous bacterial peritonitis due to Pasteurella multocida, a gram-negative coccobacillus found in the respiratory tract of domestic animals. The patient received timely antibiotic coverage with resolution of spontaneous bacterial peritonitis and sepsis after 14-day treatment. This case emphasizes the life-threatening nature of systemic Pasteurella multocida infection as well as an indirect way of acquiring a zoonotic infection in a patient with end-stage liver disease.

Review article: spontaneous bacterial peritonitis--bacteriology, diagnosis, treatment, risk factors and prevention

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection in patients with cirrhosis and ascites.

AIM

To review the known and changing bacteriology, risk factors, ascitic fluid interpretation, steps in performing paracentesis, treatment, prophylaxis and evolving perspectives related to SBP.

METHODS

Information was obtained from reviewing medical literature accessible on PubMed Central. The search term 'spontaneous bacterial peritonitis' was cross-referenced with 'bacteria', 'risk factors', 'ascites', 'paracentesis', 'ascitic fluid analysis', 'diagnosis', 'treatment', 'antibiotics', 'prophylaxis', 'liver transplantation' and 'nutrition'.

RESULTS

Gram-positive cocci (GPC) such as Staphylococcus, Enterococcus as well as multi-resistant bacteria have become common pathogens and have changed the conventional approach to treatment of SBP. Health care-associated and nosocomial SBP infections should prompt greater vigilance and consideration for alternative antibiotic coverage. Acid suppressive and beta-adrenergic antagonist therapies are strongly associated with SBP in at-risk individuals.

CONCLUSIONS

Third-generation, broad-spectrum cephalosporins remain a good initial choice for SBP treatment. Levofloxacin is an acceptable alternative for patients not receiving long-term flouroquinolone prophylaxis or for those with a penicillin allergy. For uncomplicated SBP, early oral switch therapy is reasonable. Alternative antibiotics such as pipercillin-tazobactam should be considered for patients with nosocomial SBP or for patients who fail to improve on traditional antibiotic regimens. Selective albumin supplementation remains an important adjunct in SBP treatment. Withholding acid suppressive medication deserves strong consideration, and discontinuing beta-adrenergic antagonist therapy in patients with end-stage liver disease and resistant ascites is standard care. Liver transplant evaluation should be undertaken for patients who develop SBP barring contraindications.

Antimicrobial resistance and virulence gene profiles in P. multocida strains isolated from cats

Cats are often described as carriers of Pasteurella multocida in their oral microbiota. This agent is thought to cause pneumonia, conjunctivitis, rhinitis, gingivostomatitis, abscess and osteonecrosis in cats. Human infection with P. multocida has been described in several cases affecting cat owners or after cat bites. In Brazil, the cat population is approximately 21 million animals and is increasing, but there are no studies of the presence of P. multocida in the feline population or of human cases of infection associated with cats. In this study, one hundred and ninety-one healthy cats from owners and shelters in São Paulo State, Brazil, were evaluated for the presence of P. multocida in their oral cavities. Twenty animals were positive for P. multocida , and forty-one strains were selected and characterized by means of biochemical tests and PCR. The P. multocida strains were tested for capsular type, virulence genes and resistance profile. A total of 75.6% (31/41) of isolates belonged to capsular type A, and 24.4% (10/41) of the isolates were untypeable. None of the strains harboured toxA, tbpA or pfhA genes. The frequencies of the other genes tested were variable, and the data generated were used to build a dendrogram showing the relatedness of strains, which were clustered according to origin. The most common resistance profile observed was against sulfizoxazole and trimethoprim-sulphamethoxazole.

Pasteurella multocida infection in cats: ABCD guidelines on prevention and management

OVERVIEW

Pasteurella species are part of the normal oral flora of cats. They are also a common cause of infection in this species and an important zoonotic agent. INFECTION IN CATS: Pasteurella species are commonly isolated from subcutaneous abscesses and pyothorax in cats. They may also cause secondary lower respiratory tract infection and have been associated with spinal empyema and meningoencephalomyelitis. INFECTION IN HUMANS: Disease in humans mainly occurs after a cat bite or scratch, but may also be transmitted via respiratory secretions from cats in close contact with a person. Signs of local infection after a cat bite appear in a few hours (3-6 h). Severe disease and a fatal outcome mostly occur in immunocompromised people, but have also been reported in immunocompetent healthy individuals. Cat ownership by immunocompromised people may carry a risk.

Pasteurella multocida: from zoonosis to cellular microbiology

In a world where most emerging and reemerging infectious diseases are zoonotic in nature and our contacts with both domestic and wild animals abound, there is growing awareness of the potential for human acquisition of animal diseases. Like other Pasteurellaceae, Pasteurella species are highly prevalent among animal populations, where they are often found as part of the normal microbiota of the oral, nasopharyngeal, and upper respiratory tracts. Many Pasteurella species are opportunistic pathogens that can cause endemic disease and are associated increasingly with epizootic outbreaks. Zoonotic transmission to humans usually occurs through animal bites or contact with nasal secretions, with P. multocida being the most prevalent isolate observed in human infections. Here we review recent comparative genomics and molecular pathogenesis studies that have advanced our understanding of the multiple virulence mechanisms employed by Pasteurella species to establish acute and chronic infections. We also summarize efforts being explored to enhance our ability to rapidly and accurately identify and distinguish among clinical isolates and to control pasteurellosis by improved development of new vaccines and treatment regimens.