Although musculoskeletal complaints, is quite prevalent in childhood, but JIA is a rare in comparison to adult arthritis.
Definition: inflammatory arthritis, persisting more than 6 weeks, occurring before the age of 16 years, for which no apparent cause can be found.
The diagnosis is basically a matter of exclusion of other known causes of arthritis in this age group like "anxiety, metabolic, Rickets, tumor, sepsis, hematological, reactive arthritis, trauma, lupus, serum sickness,... etc.".
JIA are classified according to pattern of arthritis, in the 1st few months of the disease into:
1- Oligo-arthritis: (either persistent oligo-arthritis or it extended to poly-arthritis).
It is the most common form, affect four or fewer mainly the large joints of lower limbs, mainly affecting the girl of preschool age.
Prognosis in general is good, but 30% of cases may progress to severe poly-arthritis {extended}, and 50% have positive ANA, HLA-DR5, which carry a high risk of asymptomatic chronic anterior Uveitis, which obligate regular ophthalmologicl slit lamp examination to early detect this serious complication.
2- Poly-articular type: of two types:
a- RF –ve polyarthritis: "commoner than RF+ve poly-articular".
Mainly affecting girl of preschool age, the arthritis usually symmetrical affecting large and small joints of upper and lower limbs.
(It may be ANA +ve with risk of chronic uveitis).
C. spine is commonly involved, early fusion of c. spine and mandible may occur ,resulting in short stiff neck with recessed chin, which usually carry subsequent dental problems in adulthood.
About 2/3 of patients may have residual damage of affected joints into adult life, some cases may have severe, damaging arthritis.
b- RF +ve polyarthritis: Mainly in older girls, usually over 8 years, similar to severe adult RA, mainly having vasculitis, erosive and damaging arthritis with rheumatoid nodule, may continue to adult RA, there is an increased association with HLADR4.
3- Psoriatic arthritis: In child with skin or nail psoriasis or family history of psoriasis or dactylitis. The arthritis usually asymmetrical oligo-articular, and may associated with Uveitis.
4- Enthesitis-related arthritis: Oligo-articular, mainly older , adolescent boys, mainly affecting lower limbs joints, asymmetrically, with enthesitis. May have a family history of sero-negative arthropathies, Uveitis and inflammatory bowel disease. It is equivalent to adult AS, but spondylitis is rare in childhood. 75% having HLA-B27, most of them evolve to adult ankylosing spondylitis.
5- Systemic arthritis " still s " : Least common, affecting both gender equally, it could occur in any age, but mainly in very young age group.
Systemic extra-articular manifestations more dominant than arthritis itself. Lymphoadenopathy, hepatosplenomegally, and pleuro-pericardial effusion are the main systemic manifestations, making the malignancies and sepsis are the main differential diagnosis. But the presence of characteristic spiking fever and evancent skin rashes are helpful clues for diagnosis. Remission may occur after few
months, but about 1/2 of the cases have recurrent attacks, about 1/3 the arthritis may run into severe chronic form with subsequent secondary amyliodosis may occur.
6- Other articular form: either not fit to any above categories , or may belong to more than one category.
Complications: There are special features of physical, psych. and social morbidity in JIA:
1- Uveitis: It is very serious complication, because it is potentially blinding at this complication is asymptomatic and even may occur in absence of active synovitis. So regular, frequent slit lamp examination is a must for early detection of this serious complication especially in those with oligo-articular of ANA +ve cases.
2- Growth disturbance: due to
a- generally the growth suppression, due to active disease.
b- by long term glucocorticosteroid therapy.
c- local effects of synovitis may diminish or accelerate epiphysial growth.
d- early fusion of epiphysis [short limbs, micrognathia].
3- Loss of schooling and family disruption, social and psych. conseq. for child and family.
Management:
* Team approach: The ideal management is through well trained medical team of " pediatricians, rheumatologists, surgeons, social workers, occupational workers, nursing staff, psychologists and others ".
* Education about the nature of the disease, importance of physiotherapy, regular control and evaluation, providing school education in case of school absence, this education programs should be directed to the parents and school staff.
* Active physiotherapy, to prevent deformities, contracture, and relief pain. Rest is indicated in early active disease, but you should avoid prolong rest to get rid of contractures, especially the knee and hip, knee joints, so it is important to instruct the patient and parents about the periodic prone position to avoid such contractures, the aim is to keep the child ambulant as early as possible, with strengthening exercises, stretching exercises, sometimes in swimming pool "hydrotherapy" is highly essential to prevent contractures and maintain range of motion.
Drug therapy:
* NSAID doses are used according to body wt. for pain and symptoms relief.
* It is well tolerated and relatively safer in children in comparison to adult, this might be due to rapid hepatic metabolism and renal excretion, higher ability for mucosal repair, (Asprin should be avoided due to possibility of Reye s disease).
* If synovitis persist or there is enthesitis does not respond to above measures, intra-articular or intra-lesional corticosteroid is beneficial.
* Early consideration of slow acting anti rheumatic disease, especially in RF +ve polyarthritis, systemic polyarthritis, extended oligo-arth., severe psoriatic arth., and severe persistent oligo-arthritis, which not respond to above measures. Methotrixate and sulfasalazine are the most effective agents.
Etanrecept is of benefit in persistent poly-articular JIA.
* Long term corticosteroid, should be never used as a routine line in treatment, it should be reserved only for children with: life threatening systemic disease, for the children with chronic Uveitis not responding to local therapy. But should be considered an alternate day treatment or short courses with early tapering, to avoid side effects, especial growth suppression [as small as dose of 3mg/day can inhibit growth in children under 5 years], corticosteroid do not arrest the disease progression.
* Surgery: indicated mainly, for released of contractures, in form tenotomies, osteotomies to correct mal-alignment. Total hip arthroplasty, can be considered in severe and damaged hip joint, but should be done after the growth has been ceased.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .