Introduction
Wounds that won’t heal on cats can be very concerning for pet owners. A wound that persists longer than expected could indicate an underlying problem. Signs like continued bleeding, swelling, redness, pain, or discharge may suggest the wound has become infected or is not healing properly. This can lead to further complications if not treated. Understanding the various causes of poor wound healing in cats is the first step to getting your pet the care they need for recovery.
Common Causes of Non-Healing Wounds
There are several common causes of non-healing wounds in cats:
Infection
Infected wounds occur when bacteria, viruses, or fungi enter a wound and begin to multiply. Signs include pus, redness, swelling, odor, and pain. Infections prevent proper healing and need to be treated with antiseptics and antibiotics (Calfee, 2002).
Underlying Disease
Diseases like diabetes, kidney failure, and hyperthyroidism can impair wound healing. Poor blood circulation, reduced immunity, and nutritional deficits contribute. Underlying illness may need to be managed to allow wounds to heal.
Poor Blood Supply
Adequate blood flow delivers oxygen and nutrients necessary for healing. Areas with compromised circulation, like pressure points or limbs with arterial disease, tend to have non-healing wounds.
Foreign Objects
Foreign material like wood splinters, glass, gravel, or plant awns lodged in wounds prevent proper healing. Wounds should be thoroughly flushed and foreign objects removed.
Cancer
Feline injection site sarcomas, squamous cell carcinomas, and other skin cancers can lead to chronic non-healing wounds. Biopsies help diagnose cancer, which requires specific treatment.
Signs of Infection
Some of the common signs of an infected wound in cats include:
Pus – The presence of pus, which is a yellow or greenish fluid composed of dead cells, bacteria, and debris, is a telltale sign of infection. Pus will often ooze or drain from the wound site.
Redness – An infected wound will often appear more red and inflamed around the edges. This is caused by increased blood flow and inflammation to fight the infection.
Swelling – Swelling around the wound often occurs as the cat’s immune system responds to the infection. This is due to fluid and inflammation in the tissue.
Pain – The area around the wound will likely be painful. The cat may whimper or cry out if the area is touched. There may be reluctance to move the affected body part.
Heat – An infected wound and the surrounding tissue often feels hot to the touch due to increased blood flow to the area.
Foul Odor – An infected wound may produce a foul, unpleasant odor from the bacteria and dying tissue present.
According to VCA Animal Hospitals, if signs of infection are present, a veterinarian should examine the cat right away to determine the appropriate treatment.
Underlying Diseases
Certain diseases in cats can impair wound healing. Diabetes is one of the most common diseases that delays wound healing. Cats with uncontrolled diabetes often have poor blood circulation and a weakened immune system, which inhibits the body’s ability to deliver nutrients, oxygen, and infection-fighting cells to the wound site (Source).
Kidney disease is another condition that impairs wound healing in cats. Reduced kidney function leads to the buildup of waste products in the blood, resulting in impaired immunity, poor wound oxygenation, and nutritional deficiencies – all factors that are important for proper wound healing (Source).
Hyperthyroidism can also delay wound healing due to the increased metabolism in cats with this disease. The excess thyroid hormones raise the cat’s basal metabolic rate, increasing their nutritional requirements. Meeting these demands is necessary for providing the nutrients required for tissue repair and regeneration (Source).
Finally, Cushing’s disease impairs wound healing because it leads to immune dysfunction and poor wound oxygenation. Getting the disease under control with medication can help improve wound healing in affected cats (Source).
Poor Blood Supply
An adequate blood supply is critical for delivering oxygen and nutrients required for proper wound healing. Damage to blood vessels near the wound site can disrupt blood flow and lead to poor wound healing. Cats that have suffered trauma, surgery complications, or blood clots are at risk for impaired blood supply.
Anemia, a deficiency of healthy red blood cells, also reduces oxygen delivery to tissues and can delay healing. Causes of anemia include blood loss, cancer, kidney disease, and nutritional deficiencies. Blood clots related to heart disease or hypercoagulability can also restrict blood flow.
If poor blood supply is suspected, a veterinarian may recommend bloodwork to check red blood cell levels, clotting times, and markers of organ function. They may also suggest imaging tests like Doppler ultrasound to assess blood flow. Treating underlying diseases and surgical techniques to repair blood vessels may help resolve poor circulation.
Foreign Objects
Foreign objects like foxtails, grass awns, splinters, glass, and thorns can lodge in a cat’s skin and cause non-healing wounds (VCA Animal Hospitals). These objects create wounds by penetrating the skin. If they remain embedded in the wound, they will irritate the surrounding tissue and prevent proper healing.
Foxtails and grass awns are especially problematic as their barbed shape allows them to burrow deeper into the skin. Splinters may also embed themselves deeply in a puncture wound. Cats who go outside are prone to getting foxtails, grass awns, and splinters stuck in their paws or face.
Foreign material causes inflammation and infection around the wound. Signs include pain, swelling, redness, heat, and pus draining from the wound. The cat may constantly lick at the area trying to dislodge the object. Foreign objects need to be surgically removed so the wound can heal. Leaving them in place leads to chronic infection and tissue damage.
Cancer
Certain types of cancer can lead to non-healing wounds in cats. Squamous cell carcinoma and mast cell tumors are two of the most common cancers that cause persistent skin lesions and ulcers in felines. Squamous cell carcinoma often appears as crusted, non-healing sores on the head, nose, ears, eyelids, or mouth. Mast cell tumors lead to hairless, raised lumps or ulcers on the skin that continuously break open and bleed. Biopsies are required to confirm cancer diagnoses.
According to the Cornell Feline Health Center, lymphoma is another cancer that impairs wound healing in cats [1]. Lymphoma causes fragile blood vessels and low platelet counts, making it difficult for blood to clot and wounds to heal. Cats with lymphoma can be treated with steroids and chemotherapy to help manage the disease.
Diagnosis
To diagnose the underlying cause of a non-healing wound in cats, veterinarians will perform a thorough physical exam, looking for signs of infection, foreign objects, or tumors. They may also recommend the following diagnostic tests:
Blood tests can look for issues like diabetes, kidney or liver disease, cancer, and infections that may impair wound healing.
Imaging such as X-rays, ultrasound, or CT scans can detect foreign bodies like glass or splinters. Imaging can also identify bone involvement, tumors, and fluid buildup.
Biopsies of the wound tissue can diagnose cancer or other disorders impairing healing.
Treatment
The treatment for a non-healing wound in cats will depend on the underlying cause. According to the VCA Animal Hospitals, the first step is to identify and address any underlying factors impairing healing such as poor blood supply, foreign objects, infection, or cancer (VCA Animal Hospitals). Some common treatments include:
– Addressing any underlying illnesses like kidney disease or diabetes that could be affecting wound healing.
– Surgical exploration and removal of any foreign objects stuck in the wound according to the WSAVA 2018 Congress (WSAVA 2018 Congress).
– Prescribing antibiotics if infection is present. Antibiotics may be given orally or topically.
– Debridement of any necrotic tissue in the wound bed, which can host infection and prevent healing according to the WSAVA (WSAVA 2018 Congress).
– Tumor removal surgery, radiation, or chemotherapy if underlying cancer is found.
– Improving blood supply to the area with surgery or medication if poor circulation is impairing healing.
– Bandaging and protection of the wound site to keep it clean while healing.
– Skin grafts or flaps if the wound is very large or deep.
Consulting a veterinarian is important, as they can properly diagnose the cause of impaired healing and prescribe appropriate treatment. With proper treatment of the underlying issue, many non-healing wounds in cats can go on to fully resolve.
Prevention
There are several steps cat owners can take to help prevent non-healing wounds in cats:
Keep cats indoors – Keeping cats inside reduces their risk of trauma from fights with other animals, getting hit by cars, and other outdoor hazards that can cause wounds.
Check for foreign objects – Carefully inspect wounds and ensure no foreign material like grass, dirt, glass, or wood splinters are trapped in the wound as these can prevent healing.
Monitor wounds – Check wounds daily for signs of infection like pus, swelling, redness, and pain. Contact your vet if you notice any concerning changes.
Routine vet care – Keep your cat up to date on vaccines and have your vet examine any wounds at your cat’s regular checkups. Vets can debride, clean and close wounds properly.
Proper nutrition – Feed your cat a nutritious diet to support wound healing and immune system function.
Reduce stress – Limit stressful situations during wound healing as stress can impair the healing process.
