Sjogren's syndrome, a chronic autoimmune disease, affects mainly women and in 2011 halted the career of Australian Open 2017 finalist Venus Williams.

WHAT IS SJOGREN'S SYNDROME?

An autoimmune disease where the tear and salivary glands are attacked by the body's own immune cells. It is the second most common autoimmune disorder after rheumatoid arthritis.

It is a debilitating disease that can greatly impair a person's quality of life. US tennis champion Venus Williams once said it left her feeling "beat up" daily .

WHO DOES IT AFFECT?

It's estimated 90 per cent of sufferers are women: on average they are diagnosed between 40 and 50 years of age. According to the Australian Sjogren's Syndrome Association it strikes up to 0.5 per cent of all Australians.

WHAT CAUSES IT?

Viral infections, hormones, genetics and stress trigger autoimmune diseases. In 2014, University of Western Australia researchers found chronic cytomegalovirus (CMV) infection - a member of the herpes family that causes mild flu-like symptoms - can trigger sjogren's syndrome.

IS IT LIFE THREATENING?

It is generally not fatal if complications are diagnosed and treated early. Sjogren's syndrome patients must be monitored carefully for development of internal organ involvement, related autoimmune diseases and other serious complications. The incidence of lymphomas (cancer of the lymph nodes) is significantly higher in people with sjogren's. In one study, the incidence of lymphoma was 44 times higher.

IS THERE A CURE?

No and treatment is aimed at relieving the symptoms.

SYMPTOMS:

• Dry eyes, few or no tears, redness, burning, light sensitivity, eye fatigue and itching
• Dry mouth, difficulty chewing, swallowing food or speaking, a burning feeling of the tongue, altered taste and the need to frequently drink fluids
• Bacterial growth in the mouth, dental decay, periodontal disease and oral yeast infections
• Dry ear and nose, sometimes middle ear problems and a reduced sense of smell
• Fatigue and/or depression, vaginal dryness, joint pain and swelling, numbness and pins and needles, muscle weakness, dizziness, nausea, vomiting, early satiety and abdominal bloating, kidney stones.

(Source: The Australian Sjogren's Syndrome Association, Garvan Institute of Medical Research)