Addressing Cat Bite Abscesses
Posted by Arnold Plotnick, DVM on 9/7/2007 in Scratching Post Articles
Although cats living together indoor occasionally fight over territory or for owner attention, it rarely leads to serious injury. However, when cats encounter other cats outdoors, fights are likely to occur – usually over territory.
A cat’s sharp teeth can produce puncture wounds when they bite. But the full damage goes beyond the wound due to the tremendous amount of bacteria inside a feline mouth.
Let’s run down the dangerous scenario:
The puncture wound seals quickly and bacteria injected into the skin become trapped.
The bone marrow sends out many white blood cells to help fight this infection.
The white blood cells and bacteria accumulate to form a painful pocket of pus just beneath the skin.
This collection of pus is an abscess. Abscesses are common in cats, owing to the tough, elastic nature of feline skin, which readily seals over contaminated puncture wounds, allowing for pus to accumulate beneath the skin.
Trauma and infection are not the only concerns regarding cat bite injuries. Feline feuds can result in the transmission of several life threatening infectious diseases from one cat to the other. Examples include feline leukemia (FeLV) virus, feline immunodeficiency (FIV) virus, Bartonella and rabies. Even worse: some of these infectious diseases, particularly Bartonella and rabies pack zoonotic powers – meaning that these infections can be transmitted to humans.
The diagnosis of an abscess is based on history and physical examination findings by your veterinarian. Top candidates for abscesses are cats who spend time outdoors, especially intact males who are more likely to roam and tussle over turf rights than neutered males or spayed females.
Unfortunately, detecting bites in a cat can be difficult because cats often appear to look fine after an encounter. Over the next two to four days after a fight, bacteria deposited in the wound begin to multiply. The cat develops a fever, becomes lethargic and often stops eating. Many cats are taken to the veterinarian at this stage, where the abscess appears as either a firm or soft painful swelling.
If not discovered in this early stage, the abscess will continue to swell, burrowing through tissues and accumulating more pus. The abscess may then burst through the overlying skin, releasing creamy yellow or brownish, often foul-smelling pus. Overlying hair may become matted with dried discharge.
Common locations for abscesses are the face and neck, tail, back and legs – although any part of the body can be bitten during a fight. If a bite wound occurs in a location that does not have much loose skin, such as a leg, the infection can dissect its way through the tissues, causing diffuse swelling instead of a discrete collection of pus. This diffuse swelling is called cellulitis.
The goal of treatment is to prevent further contamination by cleaning the wound, removing dead tissue and treating for infection. The earlier a cat receives treatment, the better the chance that the wound will heal without complication.
In most cases, a cat is anesthetized so an incision can be made into the abscess. The wound is then flushed with an antibacterial solution to further remove pus and other debris. If detected and addressed at an early stage, lancing and flushing (plus antibiotics) may be all that is required.
If discovered at a later stage, where significant tissue damage has occurred beneath the skin, your veterinarian may need to debride the wound (that is, remove dead or compromised tissue). In some cases, the veterinarian may find it necessary to insert a drain (a piece of soft rubber tubing that exits at the lowest point of the wound) to allow any future accumulation of fluid or pus to escape.
After debriding – if the wound is large – sutures may be required to partially close it, however, most wounds are left open to drain and heal on their own. Very large skin defects may require some type of reconstructive skin surgery after the infection has resolved. Once an abscess is opened up so that pus can drain, most cats immediately begin feeling better.
Antibiotics are vital because oral bacteria are literally injected below the skin during the biting process and nearly all of these wounds are infected. Penicillin derivatives are the antibiotics of choice. Pus that has a particularly putrid smell usually indicates that anaerobic bacteria – bacteria that thrive in environments where oxygen is low or absent – are involved in the infection. In these cases, antibiotics known to be effective against anaerobes should be administered. A short course – perhaps 5 to 10 days – is typically all that is required.
Occasionally, some bite wound infections do not respond to initial antibiotic therapy, and a bacterial culture and sensitivity test may be required to determine which specific bacteria are infecting the wound and which antibiotics are most effective.
The prognosis for a properly treated abscess is excellent. Yet, cats who engage in frequent fights are at high risk for contracting serious illnesses, such as FeLV and FIV. Cats who contract these viruses may then spread them to other cats in future encounters.
Cats with FeLV or FIV also have weakened defenses against infection, and may have difficulty defeating an infection if bitten by other cats. Outdoor cats should be regularly tested for these viruses. Although the majority of cats will test positive within several weeks of being bitten by an infected cat, a cat that tests negative should be retested no sooner than 90 days after exposure, to rule out false negative results obtained during incubation of the virus.
Cats who go outdoors should also be current on their vaccinations, especially rabies and FeLV. A vaccine against FIV was introduced several years ago and is gaining popularity.
The best prevention is to keep your cat indoors – supervising his outdoor access by teaching him tolerate a harness and walk on a leash or provide him with a safe and sturdy outdoor enclosure. Neutering will also reduce a male cat’s desire to roam and get into fights.
Signs of an Abscess
Cats tend to mask pain. Please give your cat a thorough head-to-tail inspection each day and consult your veterinarian if your cat exhibits any of these signs:
Poor or absent appetite
Visible puncture wounds
Swelling or lump on skin
Limping (may indicate a bite on a leg)
Pain or reluctance to be picked up or touched
Fever (a healthy cat’s temperature ranges between 100 and 101 degrees Fahrenheit)
Swollen lymph nodes