What this means
A dog's skin is covered in fur, so bruises are easiest to see where the coat is thinner: the belly, the groin, the armpits, the inside of the ears or the gums. They look like blue, purple or dark red areas, and sometimes like tiny red dots that do not fade when pressed. If you remember a clear knock, a fall or your dog being held by a leg, a small bruise may be explained. Bruises with no known cause are not.
Blood can also leak when the body is worse at stopping bleeding. That happens when there are too few platelets, when they do not work as they should, when the substances that make blood clot are missing, or when the immune system attacks the body's own cells. A dog like that may have not only bruises but also a wound that will not stop bleeding, blood in the urine, stools or vomit, nosebleeds or bleeding gums.
That is why bruises of unclear origin, or bleeding, are always worth showing to a vet, even if your dog seems bright and eats. Write down where the bruises are, when they appeared, whether there are more of them, and whether your dog could have swallowed anything poisonous, such as rodent poison. If the bruises are wide or spreading, or your dog is lethargic or has pale gums, that is urgent.
Possible causes
These are things that can cause this sign. It is not a diagnosis, and they are not equally likely for your dog.
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A knock or injury
A fall, a blow or a hard squeeze can leave a bruise in that spot. If you know what happened and the bruise is small, that usually explains it, but it is still worth telling the vet.
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An attack by the immune system
When the immune system starts destroying blood cells, the blood clots less well. A dog may have bruises, tiny red dots in the skin or gums, and be lethargic.
About the condition: Autoimmune disorders -
Inherited clotting disorders
Some dogs are born lacking substances that make blood clot. Even a small injury can bleed for a long time, and blood can leak into the joints or muscles.
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A disorder of platelet function
There may be enough platelets, but they do not work as they should, so bleeding is slow to stop. Bruises or long bleeding can follow even a slight injury.
About the condition: Thrombocytopathy -
Late bleeding after a procedure
Bleeding after a tooth extraction or another veterinary procedure can start not at once but hours or days later. Before any procedure it is worth telling the vet if this has happened to your dog before.
About the condition: Delayed bleeding after a procedure -
Swallowed rodent poison
Some rodent poisons interfere with blood clotting, and the signs can show only after several days. If you suspect your dog swallowed some, go at once and take the packaging with you.
About the condition: Poisoning
What else to watch for
These observations help your vet build the picture faster. Note down what you saw and when.
- Where on the body the bruises or red dots are, and whether there are more of them
- Whether you know of a fall, a knock or another reason that would explain a bruise
- Whether the gums and the inside of the eyelids are pink or pale
- Whether there is blood in the urine, stools or vomit, or from the nose
- Whether wounds bleed for longer than usual
- Whether your dog could have swallowed poison or medicines
When to book a routine visit
Show bruises of unclear origin, or any bleeding, to a vet as soon as you can, even if your dog seems well. If the bruises are more than small, are spreading, the gums are pale or your dog is lethargic, go straight away.
Related conditions
Conditions whose entries mention this sign. The list is somewhere to read on, not a way to reach a diagnosis.
- Autoimmune disorders Blood and immunity This is an umbrella term for conditions in which the immune system, instead of defending the body against germs, starts attacking the dog's own tissues. The skin, blood cells, joints or internal organs can be affected, so these diseases can look very different from one another. What the condition is and what caused it is for the vet to determine.
- Hemophilia A Blood and immunity Hemophilia A is an inherited blood-clotting disorder in which the body lacks one of the clotting factors, so blood clots too slowly. Even a minor injury can bleed for a long time, and blood can also leak into the joints or muscles. Bleeding that will not stop is life-threatening, so the dog then needs a vet immediately.
- Thrombocytopathy Blood and immunity Thrombocytopathy is a blood clotting disorder in which the blood has enough platelets but they do not work as they should, so bleeding is slow to stop. It can be inherited or arise from another illness or certain drugs. In such a dog even a small wound or a veterinary procedure can lead to prolonged bleeding, so it is worth telling the vet about it beforehand.
- Von Willebrand disease Blood and immunity Von Willebrand disease is an inherited bleeding disorder in which the body lacks a protein that helps platelets stick together and plug a damaged blood vessel, or the protein doesn't work properly. As a result even a small wound can bleed for longer than normal, and the disease varies in severity, sometimes only coming to light after an injury or a procedure. Genetic tests exist for some forms.
- Delayed bleeding after a procedure Blood and immunity This is a condition in which bleeding after a tooth extraction or another veterinary procedure starts not straight away but hours or even days later. At first everything can look fine, so before any procedure it is worth telling the vet if this has happened to your dog before. Bleeding that starts later can be dangerous, and then the dog needs a vet immediately.
- Anaplasmosis Infections Anaplasmosis is a tick-borne bacterial infection whose bacteria settle inside white blood cells. In Lithuania it is spread, like Lyme disease, by the castor bean tick. Some infected dogs show no signs, while others develop a fever and a limp within a few weeks of the tick bite; what caused the illness is for a vet to establish.
- Poisoning General health Poisoning happens when a dog swallows, breathes in or absorbs through its skin a substance that harms its body. Much of what is found in a home and garden is dangerous to a dog: rodent bait, antifreeze, chocolate, grapes and raisins, the sweetener xylitol, preparations meant for people. Even if the dog seems well, it needs a vet immediately.
Body systems: Blood and immunity Infections General health