Ankylosing spondylitis is a type of arthritis that leads to chronic pain and discomfort, usually in the spine.

It is important to understand the early signs and symptoms of the disorder, as well as how it progresses. Understanding ankylosing spondylitis (AS) may help people know when they should see a doctor and what to expect from their diagnosis.

This article aims to provide a visual guide to how AS affects the body and how this changes over time.

There is no single test to diagnose AS. Doctors will often use X-rays, CT scans, and MRIs to find evidence of inflammation in key areas, such as the joint between the sacrum and ilium.

Doctors will also want to gather more information about the type of back pain the person is experiencing. People with AS usually have symptoms before the age of 45, and their symptoms develop gradually, usually over a period of 3 months or more.

People with AS also commonly suffer from back pain that gets worse while they sleep, and then starts to feel better once they are in motion. The pain caused by AS will often not improve from resting, and tends to get better with exercise and physical motion.

Doctors will often ask people whether these situations apply to them and then move on to imaging to confirm that it is AS.

There is also a blood test that looks for a gene called the HLA-B27 gene. While having the gene does not mean that someone will have the disorder, it does appear in many cases.

When to see a doctor

Anyone experiencing symptoms linked to AS would benefit from a visit to their doctor. The doctor may run tests themselves or refer the individual to a rheumatologist for testing.

People who have been diagnosed with AS, even those with minor symptoms that can be managed at home, should continue to see a rheumatologist at least once a year. These checkups allow a doctor to track the progress of the disorder, and to monitor for complications that may not be showing symptoms.

Treatment for AS involves many different approaches designed to make the symptoms manageable.

A typical treatment plan will include physical approaches, such as exercise, physical therapy, and practicing correct posture. These plans can also include medication and applying heat or cold to relax muscles and reduce pain. Severe cases may require corrective surgeries to keep the spine in place.

Because AS has the potential to progress over time, doctors often use medications that will help slow this progression as much as possible. Research published in Arthritis & Rheumatology suggests that using drugs called nonsteroidal anti-inflammatory drugs (NSAIDs) greatly benefit people with AS, as they reduce the inflammation that causes symptoms.

Other drugs called tumor necrosis factor inhibitors are also commonly used alongside NSAID treatment. These drugs inhibit a protein called TNF-a, which plays a key role in the symptoms of AS.

Oral glucocorticoids may also be prescribed for some people with AS. These are drugs that help to suppress an overactive immune system and have anti-inflammatory effects. They are not popular because of their side effects, however, and the latest research suggests not using glucocorticoids when treating AS.

AS affects everyone differently. Some people hardly notice their symptoms and can manage them from home while others are severely affected by them.

It is important for people with AS to see a doctor or rheumatologist regularly to check on the progression of any symptoms, and to follow their treatment plan. Doing so provides people with AS the best chance of managing their symptoms.