Pancytopaenia in cats: a devastating problem in 2021

In May 2021 veterinary experts in the U.K. began to identify an unexplained surge in cats of a problem termed pancytopaenia. Some brands of cat food were recalled as this outbreak was investigated. We looked at what pancytopaenia is, the possibility of a link to particular cat foods at that time and how, as a cat carer, you might have responded.


Pancytopaenia in cats: should I be worried?

This is the questionnaire we began with when we first published advice about the wave of affected cats that occurred in 2021:

Should you be worried? Two questions to get you quickly to an answer:

  • Has your cat been on food from the Applaws, AVA or Sainsbury’s range? Note that not all foods from these brands are involved.
  • Is your cat showing any signs of illness?
  • Has your cat been on food from the Applaws, AVA or Sainsbury’s range? Note that not all foods from these brands are involved.
  • Is your cat showing any signs of illness?

If you can answer ‘No’ to both of these questions, you can put your mind at rest.

If you answered ‘Yes’ to the first question, head to the top of our FAQs to check whether the particular food you’ve been feeding is involved. If so, move that food out of reach of your cats, retrieve the packaging and read on to learn more.

That answer related to a time when a number of diets were being recalled as suspect while attempts were made to pinpoint a cause.

If you answered ‘Yes’, but only to the second question, then our advice will always err on the safe side: contact your primary vet care provider or schedule a consultation with our Vet on the Net team for more guidance.

And that answer remains – and always will be – advice for the best. 

  • Stop feeding those foods immediately and contact the manufacturer (there are links in our FAQs) for advice on the recall
  • Identify a suitable new diet and introduce this gently, taking three or more days to build up to the full feeding amount. Try and keep to the same format (that is, dry or wet food, loaf or pâte) and meet any dietary aims you have for your cat. You may need to contact your own vet or consult with one of our team to discuss suitable alternatives.
  • You might feel that you would prefer to try raw foods, given the circumstances. However, the lack of white cells when pancytopaenia is present means your cat could be at particular risk of contracting infection from uncooked foods, so for now that looks unadvisable.
  • If your cat seems perfectly well, you need to decide whether you are content just to monitor or if you’d like to have blood tests. You may need a series of tests, perhaps two weeks apart, to be sure of any trends. Be aware that if your cat is insured but not showing any signs of illness, you should contact your insurers first to know if the costs would be covered under your policy.
  • If your cat is off colour or showing any of the signs listed, contact your primary care vet to discuss the best course of action for you (and if appropriate, the costs involved), as a matter of urgency.

There is good information on food safety and the recall at the Pet Food Manufacturers Association.

The rest of this article remains, published for information and updated to reflect the position as it was in 2021:

What is pancytopaenia?

Pronounced pan–sigh-toe-pee-nee-ya, this word literally means all-cells-low or lacking. It describes three key components of the blood (red cells, white cells and platelets) falling to dangerously low levels, either because they haven’t been made by the bone marrow (the main site for the manufacture of these particles) or because they have been used up or destroyed.

So, pancytopaenia is not a diagnosis, it’s a word that describes a lack of vital blood components but it doesn’t tell us the cause. We know ‘what’ is happening, but not the ‘why’ or ‘how’.

Pancytopaenia has been recognized in cats for decades, occurring from time to time due to a variety of diseases. Bone marrow is known to be damaged by certain viruses or cancers and by sepsis, toxins and immune conditions.

What is different about this is the sudden spike in cases around the country, in a pattern that doesn’t fit with the usual viral, cancerous or immune-mediated causes, but does suggest one common cause.

What are the signs of pancytopaenia in cats?

If we look at what the different cells and particles in the blood do, we can understand the signs we might see when their levels are seriously low.

  • Red blood cells carry oxygen from the lungs to all other tissues around the body. A lack of oxygen causes weakness and lethargy, with pallor and an increase in the rate of breathing as the body tries to compensate.
  • White blood cells form a vital part of the body’s defences against infection, so a lack of them means the risk of infections, causing fever and lethargy.
  • Platelets are an essential part of normal blood clotting. We might hear enough of clots and thrombosis to think that clotting is always bad but, at micro levels, the body is continually preventing and repairing minor bleeds. A failure to clot means haemorrhages, perhaps internally, perhaps where they can be seen externally as bruising, as blood in urine or stool, or bleeding from the eyes, nose, mouth or bottom. Lethargy, weakness and loss of appetite result from the loss of blood.

To summarise, the initial signs are usually:

  • A non-specific lethargy, weakness or loss of appetite…

… progressing to: 

  • Paler than normal mucous membranes (which include the gums, tongue, roof of the mouth and the conjunctivae which line the eyelids) – though this can be quite difficult to assess in cats
  • Bleeding or bruising
  • Collapse

Is pancytopaenia serious?

Sadly, the answer is yes. About 2 out of 3 cats who are understood to have been affected have died, despite some of them receiving extensive support and care.


Who is looking into pancytopaenia in cats?

The Royal Veterinary College (RVC) is a veterinary school in London that offers student training and first-opinion veterinary care, while its Queen Mother Hospital for Animals (QMHA) is one of the largest and most advanced veterinary hospitals in the world, providing advanced referral and research facilities. Read their information and advice here: RVC Pancytopaenia update but in summary:

On June 16th, they released this statement (abridged):

“We can confirm that we are aware of a series of cases of fatal pancytopenia in cats in the UK……after noticing an increase in cats presenting with pancytopenia in May.

Based on the evidence to date, the one aspect of these cases that formed a consistent pattern was the diet of the affected individuals.

Most cats show some non-specific signs for around two days before being seen by a vet. We encourage owners to contact their veterinary practice if they are worried that their cat may be affected. “Given this apparent association with diet, we welcome the Food Standards Agency’s product recall notice”.

Once this was identified, an urgent safety warning was issued, recalling specific cat food products.

In the last September 2021 update, there had been 565 cases known to the RVC (bear in mind that not all cases in the country will be have been known to them) of which, tragically, 63% had died. The number of new cases had fallen sharply from August onwards.

As the statement from the RVC above says, in the cats whose diet was known, this appears to have been the common factor – they had all eaten food from one of three different brands with the same manufacturer. A recent update from the Food Standards Agency does report finding mycotoxins in a small number of food samples; these are toxins produced by moulds and, though they are quite commonly found in foodstuffs and have not been confirmed as the cause, the RVC information now refers to a particular group of moulds known as trichothecenes.



Where can I find a list of the cat foods recalled because of the pancytopaenia outbreak?

Find the full lists of recalled foods at the Food Standards Agency and Food Standards Scotland

How do I contact the manufacturer to arrange the recall?

You can find links to the three affected manufacturers and their associated retail outlets here:

Applaws (dry cat food only)

AVA from Pets at Home

Sainsbury’s Hypoallergenic Dry Cat Foods

and a statement from their supplier Fold Hills Food, here. 

Will my vet know what to do?

You and your vet can find advice on testing and treatment at the RVC’s Pancytopaenia page, as well as updates on the progress of their research.

 Updated 24th November 2021