Juvenile ankylosing spondylitis (JAS) is a chronic inflammatory disorder belonging to the group of juvenile-onset spondyloarthritides. It occurs prior to the age of 16 years and primarily leads to enthesopathy, spinal abnormalities, and peripheral joint inflammation.
Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease that causes pathologic changes both axially and in the regions of ligament and tendon attachments to the skeleton . Juvenile ankylosing spondylitis (JAS) affects children and adolescents younger than 16 years of age and presents considerably differently than adult-onset AS. One of the first mentions of JAS in the scientific literature was by Moll and Wright in 1976 which described a pediatric disease that mainly leads to an inflammation of the entheses and peripheral joints, possibly progressing to axial involvement  .
The initial manifestations with which JAS patients present are that of monoarthritis or oligoarthritis that usually involves peripheral enthesitis, tarsal disease, and, relatively rarely, sacroiliitis and spinal inflammation . The predominance of lower extremity involvement is irrefutable in JAS and arthritis tends to be asymmetric. Disease progression is also fluctuant. Some patients may experience one occurrence of asymmetric arthritis that responds to treatment and does not recur, whereas others may face a progressive disease that will eventually cause serious sequelae to the affected structures . Even though it is a rare clinical manifestation diagnosed in approximately 1/5 of JAS patients, acute anterior uveitis may coexist and so may additional extra-articular manifestations, including conduction heart disease, valvular disease, and lung disease   . Spinal involvement usually appears years after the early symptoms have been observed, mostly after an average period of 6 to 8 years . Nonspecific complaints which may also be reported by the young patients include a kyphotic appearance due to progressed disease that has affected the spine, weight loss, decreased appetite, fatigue, and dyspnea.
Entire Body System
Increased Susceptibility to Infections
increased susceptibility to infections, liver disease), children who receive methotrexate therapy should be regularly monitored with kidney, liver function, and blood studies. [rarediseases.org]
One of the first mentions of JAS in the scientific literature was by Moll and Wright in 1976 which described a pediatric disease that mainly leads to an inflammation of the entheses and peripheral joints, possibly progressing to axial involvement. [symptoma.com]
Reactive arthritis was suspected due to conjunctivitis, arthritis and a previous episode of watery diarrhea. An ophthalmologic examination showed no evidence of uveitis. [ncbi.nlm.nih.gov]
knee M08.061 Unspecified juvenile rheumatoid arthritis, right knee M08.062 Unspecified juvenile rheumatoid arthritis, left knee M08.069 Unspecified juvenile rheumatoid arthritis, unspecified knee M08.07 Unspecified juvenile rheumatoid arthritis, ankle [icd10data.com]
Years ago, there were three types of juvenile rheumatoid arthritis that were recognized. In the United States, juvenile rheumatoid arthritis was also referred to as JRA, or juvenile arthritis. [verywell.com]
Juvenile Arthritis (JA) is a term used to categorize the different types of arthritis affecting children. The most common type of JA is Juvenile Rheumatoid Arthritis (JRA). [spineuniverse.com]
Low Back Pain
Juvenile ankylosing spondylitis affected youths in their early teens, who presented most commonly with appendicular joint complaints rather than low back pain. [ncbi.nlm.nih.gov]
The 1984 Modified New York Criteria for the diagnosis of AS are used to diagnose JAS as well and include: Clinical manifestations: Lumbar spine motion restriction (sagittal and frontal planes) 3 months of low back pain that improves with exercise and [symptoma.com]
Low back pain may travel down the back into the butt and thighs. The hips and back may feel stiff, tender, and painful. If the chest (thoracic spine) is affected, AS can make it difficult to take a deep breath. [spineuniverse.com]
Joint swelling 6wks: Jia/jra - general guide 1. [healthtap.com]
Joint swelling is common but is often first noticed in larger joints such as the knee. Stiffness. You might notice that your child appears clumsier than usual, particularly in the morning or after naps. Fever, swollen lymph nodes and rash. [mayoclinic.org]
JRA causes joint swelling, pain and stiffness that can last anywhere from a few months to a lifetime, depending on the individual. JRA is classified as an autoimmune disorder, a condition in which the body’s immune system attacks itself. [nynjcmd.com]
It causes joint swelling, pain, stiffness, and loss of motion. It can affect any joint, but is more common in the knees, hands, and feet. In some cases it can affect internal organs as well. [medlineplus.gov]
The joint problems involve large joints, such as the hips and sacroiliac joints. Swelling of entire toes or fingers, resulting in sausage digits, also occurs. [northshore.org]
(Level of evidence 4) 4.0 4.1 4.2 4.3 4.4 4.5 Giles LGF. et al., The clinical anatomy and management of back pain series, Volume 2 Clincal Anatomy and Management of Thoracic Spine Pain, Butterworth Heinemann, 2000: 61-66. [physio-pedia.com]
Lumbosacral Back Pain
ILAR Criteria Patients are said to have enthesitis-related arthritis if they have arthritis or enthesitis and two of the following Sacroiliac joint tenderness [either at time of presentation or in history] Inflammatory lumbosacral back pain Presence of [boneandspine.com]
Diagnosis of both juvenile and adult ankylosing spondylitis, similarly to other spondyloarthritides, is frequently delayed, with up to 10 years passing from the occurrence of the initial symptoms to the definitive diagnosis . JAS is often underdiagnosed or misdiagnosed, and the wider medical community displays a lack of adequate level of information regarding such rheumatic conditions.
The 1984 Modified New York Criteria for the diagnosis of AS are used to diagnose JAS as well and include:
- Lumbar spine motion restriction (sagittal and frontal planes)
- ≥ 3 months of low back pain that improves with exercise and aggravates by rest
- Restriction of chest expansion compared to the normative population
- ≥ grade 2 bilateral sacroiliitis
- grade 3 or 4 unilateral sacroiliitis
The diagnosis of JAS is made when at least one clinical manifestation and at least one radiologic parameter are present.
Sacroiliitis is usually diagnosed radiographically. The disadvantage of this imaging modality is that sacroiliac joint involvement will be depicted on an X-ray late in the course of the disease. Due to this reason, magnetic resonance imaging (MRI) scans has been gaining ground in the depiction of sacroiliitis in pediatric patients with suspected JAS. According to a study by Bollow et al., an MRI scan is considerably more sensitive to diagnose sacroiliac involvement in JAS patients than a plain radiograph .
Nine of the 10 patients exhibited the genetic marker HLA B27, but only one patient was homozygous for HLA B27. This prevalence of homozygosity among HLA B27 positive persons could be expected to occur by chance alone. [ncbi.nlm.nih.gov]
If your child has HLA-B27, she may have a genetic susceptibility (increased chance) of developing JAS. But it's important to remember that while most people with JAS do have HLA-B27, only a few people with HLA-B27 ever actually have JAS. [childrenshospital.org]
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- Wright and Moll. Seronegative Polyarthritis. Amsterdam. Elsevier/North Holland Publishing.1976.
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- Weisman M, Reveille M, van der Heijde D. Ankylosing spondylitis and the spondyloarthropathies. In: Burgos-Vargas R, editor. A companion to rheumatology. 3rd ed. Mosby: St Louis.2006;94-106.
- Huppertz H, Voight I, Muller-Scholden J, et al. Cardiac manifestations in patients with HLA B-27-associated juvenile arthritis. Pediatr Cardiol.2000;21:141-147.
- Camiciottoli G, Trapani S, Ermini M, et al. Pulmonary function in children affected by juvenile spondyloarthropathy. J Rheumatol. 1999;26:1382-1386.
- Feldtkeller E, Khan MA, van der Heijde D, et al. Age at disease onset and diagnosis delay in HLA-B27 negative vs positive patients with Ankylosing Spondylitis. Rheumatol Int.2003; 23:61-66.
- Bollow M, Braun J, Hamm B, et al. Use of contrast-enhanced MR imaging to detect sacroiliitis in children. Skeletal Radiol.1998; 27:606-616.