Blood tests can be done to look for antibodies in your blood. Antibodies are substances produced by your immune system (the body's defence against illness and infection) to attack germs.
In Sjögren's syndrome, the immune system produces antibodies that attack healthy areas of the body. These can be found during a blood test.
But not everyone with Sjögren's syndrome has these antibodies, so you may still have the condition even if a blood test doesn't find them.
Checking the layer of tears on your eyes
An eye doctor (ophthalmologist) may carry out a test to look at the layer of tears that forms across the front of your eyes.
This involves harmless coloured drops being placed in your eyes to make the layer of tears easier to see for a short time. Your doctor then looks at your eyes using a special microscope with a light.
If the layer of tears is very patchy, it could be a sign of Sjögren's syndrome.
Removing a piece of lip tissue
In people with Sjögren's syndrome, clumps of white blood cells, which are produced by the immune system, can form inside the cells where spit (saliva) is produced.
To check for this, a very small piece of tissue from the inside of your lip may be removed and looked at under a microscope. This is known as a lip biopsy.
Local anaesthetic is injected into your lip to numb it for the procedure.
Occasionally, some other tests may be carried out. These may include:
- a spit test – you spit as much saliva as you can into a cup over a five-minute period and the amount is then measured or weighed
- measuring how many tears you produce – small strips of paper are placed in your lower eyelid for five minutes to see how much of the paper is soaked with tears
Producing less saliva or fewer tears than normal can be a sign of Sjögren's syndrome.