Sepsis in Cats: Causes, Diagnosis and Treatment

Sepsis is likely underdiagnosed in cats, as many patients present in a different way than we’d expect. For this reason, both veterinarians and owners should be educated on feline sepsis and how an affected cat may behave.

Septic cats are at high risk of passing away, and it can be challenging to treat them effectively. However, there are effective therapy options available and many cats can make a complete recovery.

What is Sepsis in Cats?

Sepsis refers to a whole-body infection and the body’s inflammatory response to it.

Many patients will go into septic shock, whereby blood pressure becomes dangerously low and there is the potential for organ damage.

Understanding Blood Infections and Systemic Inflammation

Bacteria or toxins entering the bloodstream will cause a rapid and intense inflammatory response.

This is intended to be protective, but it can lead to reduced oxygen reaching the organs and cause organ damage.

‘SIRS’ means Systemic Inflammatory Response Syndrome. Sepsis is the medical term used to describe an infection that triggers an excessive inflammatory response.

How Sepsis Differs from a Localised Infection

When it comes to sepsis, the infection is not confined to a single area, but rather elicits a whole-body response. The widespread damage becomes quickly life-threatening.

Common Bacteria That Cause Sepsis in UK Cats

Some of the more commonly implicated bacteria in the UK include E. Coli, Staphylococcus, Streptococcus, Pasteurella and Enterococcus.

What Causes Sepsis in Cats?

There is not one specific cause of sepsis, and many infections can lead to a septic infection.

Untreated Wounds or Abscesses

Cats, especially those who go outside, are prone to wounds and abscesses.

These are often the result of a cat fight or catching their skin on barbed wire or sharp glass. If untreated, there is the potential for these localised infections to spread.

Urinary Tract or Kidney Infections

We see urinary tract infections more often in senior cats. Pyelonephritis (kidney infections) are less common and tends to be a result of bacteria travelling up from the bladder.

Signs of a UTI can include frequent urination, bloody urine, and excessive thirst. This can be confused with cystitis, an inflamed bladder not associated with infection.

Dental or Oral Infections Spreading to the Bloodstream

Again, advanced periodontal disease is more commonly seen in elderly cats.

While they don’t tend to refuse food, an owner may notice signs such as a preference for wet food, drooling, bad breath and red gums.

Post-Surgical or Post-Injury Complications

Although rare, sepsis is a potential complication when it comes to surgery.

This is especially true when an incision is made internally, such as a cystotomy (opening up the bladder) or an ileostomy (opening up the small intestine).

Weakened Immune Systems in Elderly or Sick Cats

Old and unwell patients are at a higher risk of sepsis, as their immune system is less capable of fighting off infections.

Many of these patients have chronic underlying conditions (such as kidney disease or hyperthyroidism) that can complicate matters further.

What Are the Symptoms of Sepsis in Cats?

Interestingly, the signs of sepsis in cats won’t always present as expected, which can make it tricky to diagnose.

Early Signs: Fever, Rapid Heart Rate, and Lethargy

The expected early signs, while typically seen in dogs, may not occur in cats, or may be missed.

This is possibly because the cat hides or sleeps more, and owners fail to detect these more subtle signs.

Some cats will experience vomiting and diarrhoea. A loss of appetite, fever, rapid breathing, high heart rate, and abdominal pain can also occur. Some owners confuse these signs with a viral infection or poisoning.

Advanced Symptoms: Collapse, Breathing Difficulty, or Cold Extremities

As the sepsis progresses, the signs become a lot more obvious. The cat is weak and they can have pale gums, cold paws, and altered breathing. Their pulse may be slow, even as low as 100 beats per minute.

When to Treat It as an Emergency in the UK

Sepsis in cats is always an emergency. If it is suspected, an emergency vet should be contacted immediately.

The sooner the cat sees a vet and treatment is begun, the better their prognosis.

How Do Vets Diagnose Sepsis?

Your vet will focus on how your cat is presenting at the clinic, their medical history, and the results of their physical exam. However, more than this is required to make a definitive diagnosis.

Physical Examination and Vital Signs

Cats are often weak and won’t put up much of a ‘fight’ on the consult table. Many have dry gums, an abnormal body temperature, and weak pulses.

Blood Tests and Cultures to Identify Infection

Your vet will look for changes in the white blood cell count and should also assess a blood film to visualise the blood cells and check for toxic changes.

A biochemistry profile can be run to evaluate protein levels and to check for organ failure.

Sometimes a blood culture is run, but this can be costly, and results take several days. A positive blood culture proves there is a septicaemia, and identifying the bacteria present can ensure antibiotic therapy is targeted.

Imaging

Your vet may recommend imaging, including a chest X-ray and abdominal ultrasound, particularly if they are looking to identify the source of the infection.

What is the Treatment for Sepsis in Cats?

Treatment varies for every patient, but certain principles remain true for most.

Immediate Hospitalisation and Intravenous Fluids

The sooner the cat is admitted to the clinic, the better, so aggressive fluid therapy can be started.

This counteracts the low blood pressure, improves circulation and hydration, and reduces toxin load on the body.

Some cats who are anaemic may also be given extra red blood cells intravenously.

Broad-Spectrum Antibiotics and Oxygen Support

Antibiotics are the cornerstone of therapy, as they fight off the intruding bacteria. Ideally, a culture and sensitivity test is run, and while waiting on results, broad-spectrum antibiotics are administered.

Oxygen should be delivered to the patient, as the blood is less capable of delivering oxygen to the tissues and organs.

Addressing the Underlying Infection Source

When possible, we want to identify where the bacteria have entered the body- the initial source.

This way, we can provide tailored therapy. Abscesses need to be drained, or leaking intestinal repairs require surgical correction.

Nutrition and Pain Relief During Recovery

Nutrition is key for maintaining strength and preventing muscle atrophy and hypoglycaemia. Cats should be offered very tempting food, and many are tube-fed- at least in the initial recovery phase.

For many patients, pain is a common occurrence. This needs to be recognised and controlled as much as possible, to allow for rest and a comfortable recovery.

Prognosis and Recovery in the UK

Prognosis is guarded, and not every patient will recover, even if treated promptly. If the septicaemia progresses to septic shock, the prognosis is even worse.

What to Expect After Treatment

Cats can take several weeks to get back to some normalcy after sepsis, as their body have been through a lot.

Those who develop organ failure may have lifelong disease, and this can significantly affect their quality of life and lifespan.

Follow-Up Visits and Blood Monitoring

Patients will be seen regularly in the first week or two after discharge. The vet will monitor for recurrence and ensure they are coping well.

This can include blood tests to monitor organ function and assess for markers of infection or inflammation.

Long-Term Care and Immune Support

For several weeks after discharge, cats need a low-stress, peaceful home where they can recuperate.

Offer a high-quality diet that is easily digestible, and ideally one containing additional antioxidants and probiotics.

Those with chronic underlying health issues may need to be exclusively fed a prescription diet or to take regular medicine.

They will also need regular check-ups and routine blood exams to monitor any disease progression.

How Can You Prevent Sepsis in Cats?

It is not possible to prevent sepsis in every patient, but certain interventions lower the chances of development.

Regular Health Checks and Vaccinations

Basic feline preventative healthcare includes annual vaccinations and vet checks.

Not only can this help prevent infectious disease, but it also provides an opportunity to detect medical issues early on.

Cleaning and Treating Wounds Quickly

Any wound should be assessed in a veterinary hospital, particularly those likely to become infected, such as cat bite wounds.

Clean wounds with salt water and organise an appointment at your local clinic.

Monitoring Post-Surgery Recovery at Home

The first week or two after surgery is when the risk of sepsis is highest.

Keep a close eye on your cat for any unexpected signs, and it is sensible to keep them indoors. Monitor wounds for signs such as redness, oozing, or a bad smell.

Maintaining Good Dental Hygiene

In the ideal world, you’d brush your cat's teeth daily. This won’t always be possible, and even managing it a couple of times a week can be beneficial.

When to Call an Emergency Vet in the UK

We are blessed in the UK to have a wide availability of 24/7 emergency services.

Don’t hesitate to contact your nearest provider if you have any suspicion that your cat is developing sepsis.

Learn More About Sepsis in Cats

If you have any questions about this life-threatening condition or want to discuss your own pet, please contact our team.

Sepsis in Cats FAQs

What causes sepsis in cats?

Sepsis is a severe inflammatory response triggered by a bacterial infection entering the bloodstream.

What are the early warning signs of sepsis?

Early signs include a fever, changed behaviour, rapid heart rate and stomach upset. Be aware, though, these signs can occur in many other, less serious conditions.

Can sepsis in cats be cured?

Yes, recovery is possible. The treatment consists of supportive care and antibiotics, and the sooner therapy begins, the better the prognosis.