Case StudyPathogenic Bacteriology2009

Case #7, 34, 64

Evelyn Loi

Hien Dang

Jose Cervantes Jr.

Case Summary

8:00am 65-year-old woman bitten by her cat on

dorsal aspect of the right middle finger. 4:00pm

swelling and pain the finger and dorsum of the right hand.

pain in the axilla, red streaking up the forearm, and chills.

Body temperature: 38oC

Lab Aspiration of abscess sent for culture

Operating room Incision and drainage of abscess

Key Information Pointing to Diagnosis

Age

Body temperature 38oC

Arm Red streaking Pain in axilla

Hand Erythema Swelling Warmth Tenderness of finger

Elevated WBC 12,000 /microliter

Classification,Gram Stain Results, and Microscopic Appearance of Pathogen

1. Which organism was isolated on culture of the abscess? Family: Pasteurellacaea Genus: Pasteurella Species: multocida

Gram – Coccobacilli Bipolar staining Fermentative Non-motile Facultative anaerobe

Diagnosis/Isolation/Identification/ of Pathogen

Media No growth on Mac plate Growth on Chocolate and Blood Agar

Biochemical testing Oxidase + Indole + Catalase+ Nitrate + Urease -

Diseases and Pathogenesis of Disease Caused by P. multocida

Virulence Factor Endotoxin Capsule

What is the reservoir of this organism? How do humans most commonly become infected by this organism?

Upper respiratory tract of pets and farm animals as NF Bites or scratches inflicted by dogs and cats

Diseases caused by Pasteurella

Soft tissue inflammation Purulent wounds, cellulitis, abscesses

Deep soft-tissue inflammation Tenosynovitis Septic arthritis Osteomyelitis

Which other clinical syndromes can be caused by this organism? Systemic infection (rare)

Endocarditis Meningitis

Eyes Conjunctivitis Corneal ulcer

Respiratory Pharangitis Pneumonia (patients with underlying pulmonary disease)

Therapy and Prognosis of Patient Infected with P. multocida

Cat bites are worse than dog bites because of their small, sharp and penetrative teeth.

Aggressive organism Symptoms appear within 24 hours Sensitive to antibiotics

Antibiotics Highly sensitive to Penicillin Chloramphenicol Tetracyclin Ciprofloxins

How can infection with this organism be prevented?

Young infants should avoid contact with the saliva of dogs and cats

Inform immunocompromised patients and children about Pasteurella infection and animal exposure

Don’t pet strange animals Never bother an animal that is eating or

sleeping Be sure household pets are up to date on

their vaccinations Seek medical advice if there is redness,

swelling, or pain if you suffer an animal bite.

Primary Research Article Contributing to the Understanding of the Disease caused by Pasteurella multocida Freshwater, A. (2008). Why Your Housecat’s Trite Little Bite Could Cause You Quite a Fright: A Study of Domestic

Felines on the Occurrence and Antibiotic Susceptibility of Pasteurella multocida. Zoonoses and Public Health. 55:507-513.

Purpose Identify potential antibiotic resistance Examine carriage rate

Materials and Methods Specimen collection

409 veterinary clinics, humane shelters, private residence Cats’s gingival margins

Culture and ID of specimens CBA, MacConkey

Antibiotic susceptibility testing Penicillin and Penicillin derivatives

G-tests Age, breed, food type, gingival scale, lifestyle and sex

G test No significant relationship between individual factors and the presence of

P. multocida Carriage rate is 90%

Susceptibility testing Penicillin (Penicillin derivatives) is still the suitable method to treat cat

bite wounds Canine bites far outnumber cat bites

20-80% of all cat bite wounds become infected 3-18% of dog bite wounds become infected

Results & Discussion

Antimicrobials SusceptibilityBenzylpenicillin 100%Amoxicillin-clavulanate

100%

Cefazolin 98.37%Azithromycin 94.02%

Table 1 % Susceptibility in 409 isolates of Pasteurella multocida

Biochemical test ResultCatalase production +Glucose acidification +Nitrate reduction +Indole production +Mannitol fermentation +MacConkey agar -Arginine dihydrolase production -B-Galactosidase production -Esculin production -Glucose fermentation -Protease production (gelatin hydrolysis)

-

Urease production -Table 2 Characterization of Pasteurella multocida

Take Home Message

Pasteurella multocida Diseases usually involves domestic animals such as cats and dogs Typical symptoms

abscess and cellulitis at local wounds Fever Elevated white blood cells

Diagnostics Antimicrobial susceptibility testing

Pasteurella can be aggressive (symptoms within 24 hours) however it can be treated easily. Penicillin

Prevention Inform children and immunocompromised individuals about Pasteurella infection and

animal exposure. Transmission

animal bite, scratches, licks, and inhalation

References

Freshwater, A. (2008). Why Your Housecat’s Trite Little Bite Could Cause You Quite a Fright: A Study of Domestic Felines on the Occurrence and Antibiotic Susceptibility of Pasteurella multocida. Zoonoses and Public Health. 55:507-513.

Bryant, Barbara J. et al. (2007). Pasteurella multocida bacteremia in asymptomatic plateletpheresis donors: a tale of two cats. Transfusion. 47: 1984-1989.

Green, Bryant T. et al. (2001). Pasteurella multocida Meningitis: Case Review of the last 11 Y. Scand J Infect Dis. 34:213-217

Loiez, Caroline et al. (2002). Pasteurella multocida and Intrauterine Device: A Woman and her Pets. Scand J Infect Dis. 34:473-474

Wade, T. et al. (1999). Pasteurella multocida meningitis in infancy- (a lick may be as bad as a bite). Eur J Pediatr 158: 875-878

Kimura, Ryosuke et al. (2004) Pasteurella multocida septicemia caused by close contact with a domestic cat: case report and literature review. J Infect Chemoter. 10: 250-252

McQueen, Nancy. Winter 2009. Pasteurellacaea.