What is negative by HLA B27?

Spondyloarthritis

In particular, the clinical features include the following symptoms.

Inflammatory back pain

In about 75% of patients with spondyloarthritis, the disease begins with back pain that typically begins slowly in the lumbar spine area, which increases at rest and decreases during physical activity. Often there is nocturnal pain, especially in the second half of the night. This is usually accompanied by a landed morning stiffness. Although inflammatory back pain is a major characteristic of spondyloarthritis, only about 5% of all patients who present with chronic back pain actually have spondyloarthritis. On the other hand, not all spondyloarthritis patients develop back pain.

Ankylosis

The term Ankylosis derives from the Greek expression for "stooped". What is meant is a stiffening of the spine due to ossification of the ligaments that extend over the spine and stabilize it, as well as the joints between the sternum, ribs and spine. The first sign of this is often the loss of the natural curvature of the spine: the curvature decreases in the deep spine area while it increases in the thoracic spine. If the course is very difficult, the cervical spine can be bent forward (see illustration).

Preventing the disease from progressing to stiffening of the spine is a major concern in the treatment of spondyloarthritis patients.

Fractures

Long-standing spondyloarthritis often results in osteoporosis, a reduction in bone density. The result can be broken bones that affect the spine. Osteoporosis arises on the one hand because of the restricted mobility and on the other hand as a result of the inflammatory reaction.

Peripheral arthritis

Joint inflammations that do not affect the spine often occur on the lower extremities, i.e. on the legs, and here typically asymmetrically, i.e. affecting different joints on both sides. Upper limb involvement is common in psoriatic arthritis.

Dactylitis

Dactylitis is the involvement of all joints of a finger or toe in the "beam". In contrast to rheumatoid arthritis, this also affects the end joints of the fingers. Dactylitis is typically seen in reactive, psoriatic, or undifferentiated arthritis.

Pain in the front chest, pelvic and shoulder girdles

Pain in the anterior chest wall occurs in around 15% of those affected by inflammation of the sternocostal (sternum-ribs), sternoclavicular (sternum-clavicle) and manubriosternal (joint between the upper and lower sternum parts) joints.

Shoulder and hip joint involvement is found in around 30% of all patients.

Enthesitis

Enthesitis (from the Greek for -itis = inflammation and enthetos = attached, inserted) is the inflammation of the enthesia, i.e. the attachment points of tendons, ligaments, fasciae and joint capsules on the bones. It is a characteristic of spondylarthritis.

The most common enthesitis affects the insertion of the Achilles tendon or the so-called plantar fascia (tendon plate under the foot that extends from the ball of the foot to the heel), which leads to back or lower heel pain. Other typical places are e.g. the iliac crest (upper edge of the iliac bone) or the anterior upper surface of the shin, the so-called shin plateau.

Enthesitis in the early stages can only be visualized in an MRI or ultrasound.

Eye involvement

Uveitis occurs in up to 30% of patients who are often HLA-B-27 positive. It manifests itself in pain and redness with increased tear production and sensitivity to light in the affected eye. In this case, an ophthalmologist must be consulted quickly and treatment should be carried out in order to avoid permanent eye damage.

Skin manifestation

Nail and skin changes are typical of spondylarthritis. Psoriasis with the accompanying nail changes often occurs with psoriatic arthritis.

Gastrointestinal tract involvement

Inflammatory gastrointestinal tract infections are common and can manifest themselves in bloody, slimy diarrhea.

Heart and lung involvement

In rare cases, arrhythmias can occur in the heart, which can lead to dizziness and palpitations.

Breathing difficulties can occur in advanced stages due to restricted mobility of the chest wall.

Kidney involvement

Very rarely, kidney function impairments due to protein deposits in the kidney (so-called amyloidosis) can occur.

Laboratory chemical characteristics

There is no laboratory parameter that is conclusive for spondyloarthritis. The inflammation parameters CRP (C-reactive protein) and ESR (sedimentation rate) can be increased in up to 40% of cases.

HLA-B27 is an inherited trait, like a blood group, that gives birth to the predisposition to develop certain rheumatic diseases. HLA-B27 is often positive in spondyloarthritis, but on the other hand it is not proof of the disease, as it occurs in up to 10% of the healthy population. If you have this property, so to speak, this type of blood group, you have an increased risk of developing rheumatic spinal disease, but you can also stay healthy with it for the rest of your life. Conversely, there are patients with rheumatic spinal disease in whom this HLA B27 cannot be detected.

Imaging

Structural changes can be shown in the conventional X-ray image. However, since these are only the result of inflammation, abnormalities in the initial phase of the disease are not photographed.

Sacroiliitis, i.e. inflammation of the sacrum and iliac joints, is a main distinguishing feature of spondyloarthritis and only becomes visible on x-rays a few years after the onset of the disease. Typical signs are superficial destruction of tissue structures (so-called erosions), calcium deposits (so-called sclerosis), changes in the joint space or bone stiffening (so-called ankylosis). The decisive factor is the classification of the radiological abnormalities according to the so-called New York scheme.

On the spine you can see a flattening and later calcification of the vertebral bodies at the front edge (so-called Romanus lesion). As the disease progresses, bones, so-called syndesmophytes, can develop, which later give the spine the appearance of a bamboo stick (see illustration).

In contrast to the X-ray image, magnetic resonance tomography also enables early stages of the inflammation to be shown.