Kembara Xtra - Medicine - Juvenile Idiopathic Arthritis

Kembara Xtra - Medicine - Juvenile Idiopathic Arthritis 
The most prevalent chronic pediatric rheumatologic condition is juvenile idiopathic arthritis (JIA).
JIA has been linked to serious disability.
- Age of onset: 16 years - Common symptoms: discomfort, warmth, redness, and restricted range of motion in the joints
six weeks or more of symptoms before a diagnosis
Seven subgroups of rheumatoid arthritis (ILAR) were identified based on clinical features during the first six months of illness:
- 10% of cases are systemic, with a febrile start that lasts for about two weeks with a rash, serositis, hepatosplenomegaly, or lymphadenopathy.
- Polyarticular rheumatoid factor (RF) (+): 2-7%; five or more joints involved; both large and small joints; RF positive on two tests conducted around three months apart. 
- 5 (big and small) joints are involved in polyarticular RF () (10–30%).
Oligoarticular: 30-60%; 1 to 4 joints involved; risk for chronic uveitis in antinuclear antibody (+) positive females; axial skeletal involvement in older boys. Types: Psoriatic arthritis: 5%; arthritis with psoriasis or arthritis with more than two of the following: (i) persistent (40%): knee, ankle, and elbow; (ii) extended type (20%): >4 joints after first 6 months psoriasis in a first-degree relative, dactylitis, and pitting of the nails (1)
- Arthritis and enthesitis, or one of these plus at least two of the following, is 1–11% more common. sacroiliac or lumbosacral discomfort, Reiter syndrome, acute symptomatic anterior uveitis, human leukocyte antigen (HLA)-B27 (+), history of ankylosing spondylitis, sacroiliitis with inflammatory bowel disease, acute symptomatic anterior uveitis, and acute anterior uveitis in first-degree relatives,
arthritis in a boy older than 6 years of age – Undifferentiated arthritis (11-21%): This type of arthritis exhibits symptoms that fall under two or more of the categories above but not all of them.
Musculoskeletal, hematologic, lymphatic, immunologic, dermatologic, ophthalmologic, and gastrointestinal (GI) systems are among those that are impacted. Synonyms include juvenile rheumatoid arthritis (JRA), juvenile chronic arthritis, juvenile arthritis, and Still disease.

EPIDEMIOLOGY

Males and females are equal; instances begin in childhood and affect 54% of children between the ages of 0 and 5.
Incidence
In affluent countries, 2 to 20/100,000 children under the age of 16
Prevalence
Children aged 16 to 150 per 100,000 in wealthy countries.


PATHOPHYSIOLOGY AND ETIOLOGY
Dysregulation of cellular and humoral immunity. T cells are important.
Genetic propensity; genetic loci IL2RA/CD25 and VTCN1 have been implicated
Environmental triggers that may be contagious include parvovirus B19 or the rubella virus (3).

 Complement or immunoglobulin insufficiency

Female gender: 3:1 risk factors

CONDITIONS OFTEN Associated with

Additional autoimmune diseases, chronic anterior uveitis (iridocyclitis), inadequate nutrition, and development problems


DIAGNOSIS
Age onset of 16 years and duration of objective arthritis (swelling or limited range of motion of a joint with heat, discomfort, or tenderness and no other form of pediatric arthritis) in 1 joints for >6 weeks are the clinical criteria.

HISTORY Fever, lethargy, malaise, myalgias, weight loss, morning stiffness, rash, arthralgias, and arthritis lasting at least six weeks

PHYSICAL EXAMINATION Rash, rheumatoid nodules (uncommon), lymphadenopathy, hepato- or splenomegaly, enthesitis, dactylitis (mostly in psoriatic type), loss of musculoskeletal landmarks, reduced range of motion, soreness, pain with motion, warmth

Legg-Calvé-Perthes, toxic synovitis, growing pains, and Perthes disease are among the several diagnoses.
Osteomyelitis, viral infections, mycoplasma infections, septic arthritis, and Lyme illness
Reactive arthritis: rheumatic fever, postinfectious, and Reiter syndrome
Hemoglobinopathies, hemarthrosis, rickets, osteoid osteoma, neuroblastoma, leukemia (especially acute lymphocytic leukemia), and inflammatory bowel disease
Vasculitis, Kawasaki disease, and Henoch-Schönlein purpura
sarcoidosis, systemic sclerosis, dermatomyositis, mixed connective tissue disease, systemic lupus erythematosus, and collagen diseases
Farber illness Unintentional or intentional trauma

DETECTION & INTERPRETATION OF DIAGNOSIS
Initial examinations (lab, imaging)
CBC: lymphopenia, reactive thrombocytosis, anemia, normal or raised leukocyte count (systemic), liver function test (LFT; hepatic involvement), and renal function studies (prior to treatment with nephrotoxic medications)
ESR and C-reactive protein are frequently elevated, and C-reactive protein is frequently disproportionately high. Myeloid-related proteins (MRP 8/14) are linked to flare-ups. ANA-positive patients have an increased risk of uveitis; ANA is positive in up to 70% of cases of oligoarticular JIA.
HLA-B27 positive: enthesitis-related arthritis; RF (+): 2-10% (typically polyarticular); poor prognosis; diagnostic radiography, MRI, ultrasound, and CT; no one modality has superior diagnostic value; radiograph of affected joint(s): early changes: soft tissue swelling, periosteal reaction, juxtaarticular demineralization; later changes: joint space loss, articular surface erosions, subchondral cyst MRI is more sensitive to monitoring disease activity and clinical reaction to treatment in peripheral joints, where it can measure synovial enlargement and cartilage deterioration.

Tests in the Future & Special Considerations
When analyzing dual energy x-ray absorptiometry results, use pediatric (rather than adult) controls.

Other/Diagnostic Procedures
Synovial biopsy: if synovial fluid cannot be aspirated or if infection is suspected despite a negative synovial fluid culture. Ultrasound: Check for inflammation.
Interpretation of Tests
Synovial biopsy results in the invasion of tiny lymphocytes and mononuclear cells, hyperemia, and synovial cell hyperplasia.

GENERAL MEASURES/TREATY
The main objectives are to manage the disease while it is active, reduce extra-articular symptoms, and achieve clinical remission.
All patients need routine ocular exams to detect asymptomatic eye disease, especially in the first three years after diagnosis and every three to four months for patients with oligoarticular JIA and ANA-positive patients.
Electric blanket or moist heat for morning stiffness
For contractures, splints
Weight-bearing or aquatic treatment as aerobic exercise to increase functional capability

First Line: MEDICATION

NSAIDs (ibuprofen, naproxen, celecoxib) are adequate in about 50% of cases, and their full effects take two to three months to take effect.
 cautiously: may exacerbate bleeding diatheses; use cautiously in hypovolemic and renal insufficiency situations; take with food.
Significant medication interactions include the potential to reduce serum anticonvulsant levels, inhibit the effects of loop diuretics, and increase serum methotrexate levels with NSAIDs.
- Intra-articular long-acting corticosteroids are effective right away; they reduce contractures, joint degeneration, and synovitis.[B]
Patients with oligoarthritis who do not respond well to a two-month NSAID trial or who have poor prognoses are indications.

5 joints - If high disease activity or a failed NSAID trial of one to two months, methotrexate 

Next Line

Disease-modifying antirheumatic drugs (DMARDs) like methotrexate, sulfasalazine, leflunomide, and tumor necrosis factor (TNF) antagonists (etanercept, infliximab, adalimumab) are necessary for 30–40% of patients; newer biologic therapies like IL-1 and IL-6 receptor antagonists are currently being researched.
10 mg/m2/week PO or SC of methotrexate
Etanercept: 0.8 mg/kg (maximum 50 mg/dose) given SC once every week or 0.4 mg/kg SC twice a week (maximum 25 mg/dose) for oligoarticular and HLA-B27 spondylarthritis
Infliximab: 5 mg/kg every six to eight weeks
Adalimumab: 20 mg SC every two weeks if you weigh between 15 and 30 kg; 40 mg SC every two weeks if you weigh over 30 kg.
Rituximab is prescribed for polyarticular RF+ patients who have failed two TNF-inhibitors. Tocilizumab is prescribed for RF-pJIA patients who have failed two TNF-inhibitors. Children with a history of arthritis in at least four joints and significant active arthritis despite treatment with methotrexate or arthritis in at least five joints and any active arthritis after a sufficient trial of methotrexate should start taking TNF-inhibitors.

IL-1 receptor antagonist, anakinra. Children who require a second medicine in addition to systemic glucocorticoids for the treatment of systemic rheumatoid arthritis and active fever should start receiving anakinra.

QUESTIONS FOR REFERENCE
For help managing JIA, speak with a pediatric rheumatologist.
Orthopedics when necessary for articular problems

Physical therapy is recommended in order to preserve range of motion, build muscle strength, and prevent abnormalities. Ophthalmology is also recommended for ongoing screening.
Occupational therapy to preserve and enhance age-related functional abilities Behavioral health if living with illness is challenging

SURGICAL AND OTHER PROCEDURE
For severe diseases, total hip and/or knee replacement
In the event that splinting or traction is unsuccessful, soft tissue release should be performed.
Rarely is a synovectomy performed.


CONSIDERATIONS FOR ADMISSION, THE INPATIENT, AND NURSING

To help with examination and workup, hospitalize a patient if they are unable to move around, show indications of pericarditis, have a persistent fever, or are confused about their diagnosis.
- Surgery is required
Release after the serositis and fever have subsided.

CONTINUING CARE AFTERCARE RECOMMENDATIONS
Based on medication and disease activities, patient monitoring
Aspirin and/or other salicylates: transaminase and salicylate levels weekly for 1 month, then every 3 to 4 months; methotrexate: monthly LFTs, CBC, BUN, and creatinine; NSAIDs: periodic urinalysis, LFTs, and renal function tests.

PATIENT EDUCATION Psychosocial needs; school-related concerns; behavioral coping mechanisms for discomfort and disobedience; readily accessible medical services; support groups
Functional capacity (maintaining muscle and joint function, disease control) is dependent on the effectiveness of therapy.
Patients with active disease at 6 months, polyarticular disease, a protracted pauciarticular disease course, female gender, RF (+), ANA (+), chronic morning stiffness, fast erosion appearance, and hip involvement have a poor prognosis.

Blindness, band keratopathy, glaucoma, low stature, micrognathia if the temporomandibular joint is affected, severe joint disease, disseminated intravascular coagulation, and hemolytic anemia are complications.
NSAIDs: leukopenia, renal disease, peptic ulcer, gastrointestinal bleeding, and CNS responses
Osteoporosis, avascular necrosis, DMARDs: bone marrow suppression, hepatitis, renal disease, dermatitis, mouth ulcers, retinal toxicity (antimalarials; rare), TNF antagonists: increased risk of infection, Methotrexate: Folate supplementation lessens hepatic/GI symptoms; may lessen stomatitis, and MAS: decreased blood cell precursors resulting from histiocytes degradation of marrow.