Contributors: Rosanna Marsella, David Scarff
Species: Feline | Classification: Diseases
Introduction Pathogenesis Diagnosis Treatment Outcomes Further Reading
Introduction
- Most common feline bacterial skin infection.
- Cause: common sequela to a bite or scratch.
- Signs: subcutaneous swelling, discharging pus.
- Diagnosis: history, clinical signs.
- Treatment: responds to drainage and antibiotic therapy.
- Prognosis: generally good.
Print off the Owner factsheet on abscesses Cat bite abscesses (and castration All about neutering) to give to your client.
Presenting Signs
- Pyrexia.
- Lameness in affected limb.
- Lethargy and depression.
Pathogenesis
Etiology
- Organisms normally found within cats' mouths are also found within abscesses.
- Pasteurella multocida Pasteurella multocida, Bacteroides spp Bacteroides fragilis, beta-hemolytic streptococci, and fusiform bacilli.
- For non-healing wounds consider atypical mycobacteria.
Predisposing Factors
General
- An intact male cat with access to the outside environment will fight for sexual favors.
- Cats in a population dense area will fight to maintain territory.
- Immunosuppressed individuals, eg with feline leukemia virus Feline leukemia virus or feline immunodeficiency virus Feline immunodeficiency virus, may show more severe signs, or fail to respond to appropriate therapy.
Pathophysiology
- Cat bites and scratches are major cause → subcutaneous bacterial infection.
- Bacteria are injected under the skin.
- The small puncture wound heals rapidly.
- Over the next 2-4 days bacteria multiply.
- Normal defense mechanisms may fully clear the infection.
- The infection may be walled off by fibrous tissue and rupture to the surface exuding cream → green pus with fetid odor.
- Infection may spread locally or hematogenously, leading to cellulitis, local lymphadenopathy or other organ involvement.
Timecourse
- 2-4 days.
Diagnosis
Presenting Problems
- Subcutaneous swelling.
- Fever.
- Lameness.
- Pain.
Client History
- Owner reports cat fight within previous 2-4 days.
- Swelling typically on head, shoulder, tail base or hindlimb.
- Off food.
- Recently moved to new area → territorial disputes.
Clinical Signs
- Subcutaneous swelling, often painful, situated typically on the head or neck, tail base or a distal limb.
- Regional lymphadenopathy.
- May be few systemic signs.
- May be fever, anorexia, depression and malaise.
- Lameness.
- Pain over affected site, often severe.
- Cellulitis.
Diagnostic Investigation
Hematology
- Mature neutrophilia Hematology: neutrophil.
Bacteriology
- May be considered in non-responsive cases.
- Aerobic and anaerobic culture necessary Bacteriology. Include culture for mycobacteria. Negative anaerobic culture does not rule out anaerobic infection.
Differential Diagnosis
- Concurrent infection with feline leukemia virus infection Feline leukemia virus disease or feline immunodeficiency virus infection Feline immunodeficiency virus disease.
- Other non-infectious causes of lameness.
- Other puncture wounds, eg penetrating foreign body.
- Mycoses.
- Sterile panniculitis.
- Mycobacteria spp infection Mycobacterium tuberculosis.
- Actinomyces spp infection Actinomyces viscosus.
- Nocardia spp infection Nocardia spp.
Treatment
Standard Treatment
- If already ruptured, clip and clean abscess with saline, dilute chlorhexidine Chlorhexidine or dilute hydrogen peroxide Benzoyl peroxide.
- Liberal surgical drainage in non-ruptured abscesses will require general anesthesia General anesthesia: overview or heavy sedation Sedation or sedative protocol.
- Cases which require extensive incisions will merit bandaging. If this is not possible place drain or leave open wound, eg side of face.
- Oral antibiotics for 5-7 days. Choose bactericidal (clindamycin Clindamycin licensed for this use, but bacteriostatic) antibiotics with activity against the more frequently encountered organisms. Therapeutics: antimicrobial drug
- Non-steroidal anti-inflammatories in cases with pyrexia and pain Analgesia: NSAID.
Subsequent Management
Treatment
- May get overlying skin necrosis necessitating debridement.
Outcomes
Prognosis
- Good in cats with healthy immune systems.
Expected Response to Treatment
Reasons for Treatment Failure
Further Reading
Publications
Refereed papers
- Recent references from PubMed and VetMedResource.
- Hoshuyama S, Kanoe M, Amimoto A (1996) Isolation of obligate and facultative anaerobic bacteria from feline subcutaneous abscesses. J Vet Med Sci 58 (3), 273-274 PubMed.
- Walker R D, Walshaw R, Riggs C M et al (1995) Recovery of two mycoplasma species from abscesses in a cat following bite wounds from a dog. J Vet Diagn Invest 7 (1), 154-156 PubMed.
- Beale K M (1995) Nodules and draining tracts. Vet Clin North Am Small Anim Pract 25 (4), 887-900 PubMed.
- Kanoe M, Kido M, Toda M (1984) Obligate anaerobic bacteria found in canine and feline purulent lesions. Br Vet J 140 (3), 257-262 PubMed.
- Ihrke P J (1984) Therapeutic strategies involving antimicrobial treatment of the skin in small animals. J Am Vet Med Assoc 185 (10), 1165-1168 PubMed.
- Love D N, Jones R F & Bailey M (1979) Description of strains of Peptostreptococcus anaerobius isolated from subcutaneous abscesses in cats. J Gen Microbiol 112 (2), 401-403 PubMed.