Juvenile Idiopathic Arthritis (JIA) Dr Urmila Dhakad Assistant professor Dept of Rheumatology KGMU, Lucknow 23-06-15 Definition - Juvenile Idiopathic Arthritis • Arthritis of unknown aetiology that begins before the 16th birthday and persists for at least 6 wks. • Previously known as juvenile rheumatoid arthritis (JRA) and juvenile chronic arthritis (JCA). Criteria for the diagnosis of JIA All three conditions must be met Arthritis persisting for longer than 6 weeks Arthritis beginning before 16 years of age Exclusion of other conditions associated with or mimicking arthritis Classification of JIA Based on symptoms presented during 1st 6 months of ds 1. Systemic onset JIA ( 10-15% ) 2. Oligo-articular JIA ( 50 % ) a. Persistent oligo-articular JIA b. Extended oligo-articular JIA 3. Polyarticular JIA (RF negative) ( 15-20% ) 4. Polyarticular JIA (RF positive) ( ≤5% ) 5. Psoriatic arthritis (5-10%) 6. Enthesitis related arthritis ( 5-10% ) 7. Undifferentiated arthritis ( 10-15% ) Systemic onset JIA (SOJIA) • Quotidian, high spiking fever(> 2 wk) associated with systemic features Evanescent, non-fixed, erythematous rash Hepato-splenomegaly Serositis Generalized lymphadenopathy. Systemic onset JIA (SOJIA) • Boys > girls. • Myalgias and abdominal pain during fever peaks. • Arthritis - symmetrical and polyarticular; it may be absent at onset and develop during disease course. Erythematous & evanescent rash of SOJIA. Frequently, rash is obvious only at height of fever and sometimes confined to axillary region, ant chest wall and inside both thighs. Systemic onset JIA (SOJIA) • Lab test - inflammatory response characterized by leukocytosis, hyperferritinemia, microcytic anaemia, thrombocytosis, high ESR and CRP . • Diagnosis of SOJIA can be difficult, especially at presentation, and D/D includes bacterial or viral infection, malignancy, and other rheumatic ds. Oligoarticular JIA • Oligoarthritis - arthritis that affects 4 or less joints, in absence of other features ( psoriasis, RF positivity, high spiking fever). Characterized by – Female predilection Early onset asymmetric arthritis (before 6 years of age) Positive ANA & HLA associations. High risk for developing chronic iridocyclitis Categories of Oligoarticular JIA Persistent oligoarthritis - disease remains confined to 4 or less joints. Extended oligoarthritis - arthritis extend to > 4 joints after first six months of ds. • Involvement of UL joints & high ESR at onset have been identified as predictors for evolution to extended type. Polyarticular JIA (RF negative) • Arthritis that affects 5 or more joints during first 6 months of disease in absence of RF. • Two clinical phenotypes can be identified: (1)Form that is closely similar to adult-onset RF negative RA. characterized by symmetric synovitis of large & small joints, high ESR and negative ANA. Polyarticular JIA (RF negative) (2) second form that resembles ANA +ve early- onset oligoarthritis in every aspect other then number of joint involved during first 6 months of disease. characterised by early age at onset, +ve ANA, asymmetric arthritis, female predominance, high incidence of chronic iridocyclitis. Polyarticular JIA (RF positive) • Similar to adult RA. RF is by definition positive. • Accounts for a small (≤5%) percentage of pts with JIA. • Primarily affects girls and usually presents in late childhood or adolescence. • It can be rapidly progressive and destructive. • Rheumatoid nodules are common. • failure to thrive more frequent than in RF –ve type. • Only JIA category in which Anti CCP are found. Psoriatic arthritis (PsA) • Diagnosis of PsA requires simultaneous presence of arthritis and a typical psoriatic rash or • If psoriasis is absent, presence of arthritis plus any 2 of following: A) Family history of psoriasis in a first-degree B) Dactylitis (swelling of one or more digits ) C) Nail pitting. relative; Enthesitis related arthritis • An undifferentiated spondyloarthritis. • Typically begins after age of 6 years, affects boys > girls. • Characterised initially by LL arthritis & enthesitis (inflammation at insertion of tendon/ligament/fascia ). • Most common sites of enthesitis are at insertion of achilles tendon to calcaneum and insertions of plantar fascia (calcaneum, base of 5th metatarsal & metatarsal heads), and around & below patella. Enthesitis related arthritis • Hip involvement is frequent at presentation. • Symptoms of sacroilitis and spinal arthritis are uncommon at presentation. • Uveitis - red eyes, photophobia and pain. • Family history of similar disease is often +ve. • HLA-B27 found in 50% of pts, while ANA is -ve. Undifferentiated arthritis • A category that includes patients who do not fulfill inclusion criteria for any category, or fulfill the criteria for more than one category. • About 10-15% of all JIA cases are included in this category. Clinical features of JIA • Pain • joint swelling • limping • Early morning stiffness Investigations in children with arthritis • No diagnostic tests exist. It is a clinical diagnosis. • Investigations have important role in excluding a wide range of differential diagnoses. • RF & ANA - are of no use for diagnosis. should only be used after diagnosis has been made. RF - help sub-classify children with polyarthritis ANA - determining risk of chronic ant uveitis. • Full blood count • Acute phase response (CRP and ESR) • ASO titers and other serology for infection. • Coagulation studies (haemophilia) • Autoantibodies (CTDs are suspected) • Biochemistry -for muscle enzymes, endocrinopathies. • Urine analysis and uinary catecholamines: to exclude renal involvement or neuroblastoma • Imaging -including plain x-rays of affected jts may be useful to exclude fracture, AVN, osteomyelitis, neoplasm and bone dysplasia. • USG of jts is useful to confirm effusion and USG of abdomen may help to exclude neuroblastoma. • Aspiration of jt for synovial fluid microscopy and culture is must in suspected septic arthritis. Differential diagnosis of JIA Child presenting with a single inflammed joint Septic arthritis : Staph aureus, H influenzae (non- immunised), M tuberculosis, Salmonella (sickle cell ds), Pseudomonas (puncture wounds). Reactive arthritis: secondary to extra-articular bacterial / viral infections e.g. strep, enteric bacteria, hepatitis B, parvovirus, EBV, varicella. Haemarthrosis: trauma or bleeding diathesis Malignancy: leukaemia or lymphoma should always be considered. Most common is ALL. Solid tumour A child presenting with > 1 inflamed joint Connective ts diseases: SLE, Dermatomyositis, Sarcoidosis, MCTD, HSP. Reactive arthritis Malignancy Immunodeficiency associated arthritis IBD associated arthritis Other: chronic recurrent multifocal osteomyelitis, cryopyrin-associated periodic syndromes. Child presenting with prominent systemic features Connective tissue diseases, Neoplasia Infection, Inflammatory bowel disease Auto-inflammatory disorders: o characterised by recurrent fever and arthritis often accompanied by abdominal pain & rash. o Results of gene mutations and so present from birth or at a very early age. o Familial Mediterranean fever, hyper-IgD syndrome, cryopyrin associated periodic fever syndromes, TNF receptor associated syndromes. Treatment of JIA Goals of Treatment of JIA • Suppression of inflammation • Pain management • Preservation of muscle strength • Prevention of jt destruction, muscle atrophy, asymmetric growth and other long-term sequelae. Treatment of JIA Non-steroidal anti-inflammatory drugs (NSAIDs) Used in higher doses relative to body weight, than in adults because children have increased rates of metabolism and renal excretion. Majority of early JIA patients respond partialy to NSAIDs and need more aggressive treatment. • Glucocorticoids Intra-articular steroids - Single injection resolves signs of inflammation for several months Pulses of IV methylprednisolone - For control of severe systemic arthritis. lifesaving in case of pericarditis with tamponade or MAS. Oral steroids - Chronic use can lead to adverse effects: growth and immune suppression, cataract, DM, AVN, vertebral collapse and Cushing syndrome. Disease modifying anti-rheumatic drugs (DMARDs) Methotrexate - effective in approximately 70% of children with polyarthritis but much less so in systemic arthritis Sulfasalazine - particularly effective in ERA. Also efficacious in oligoarthritis and polyarthritis. Leflunomide Biologicals – • Whose ds is not controlled with NSAIDs, steroids and DMARDs or who are intolerant of it. • Significantly alter natural history and stopped progression of ds in a substantial portion of pts. • Adverse events: infections, neutropenia, and increased aminotransferase levels TNF alpha blockers – Etanercept, Infliximab. polyarthritis/extended oligoarthritis. less effective in patients with systemic JIA. Anti IL-1 drugs – Anakinra, Canakinumab. effective in pts with SOJIA Anti IL-6 drugs – Tocilizumab. efficacious in severe, persistent SOJIA Other drugs • Hydroxychloroquine - RF positive polyarthritis. • Cyclosporine A - efficacious in treating MAS associated with SOJIA. • Cyclophosphamide – severe recalcitrant SOJIA for whom even biological therapies are not working. • Autologous stem cell transplantation - recalcitrant SOJIA unresponsive to all other therapies. Complications of JIA (1) Macrophage activation syndrome (MAS): • Occur in aprox. 7% of pts with systemic JIA. • Secondary haemophagocytic histiocytosis occurring in active ds. • Associated with high morbidity and mortality. Characterised by – Diffuse intravascular coagulation. Hepatosplenomegaly Pancytopenia Abrupt decrease in ESR High serum levels of ferritin, liver enzymes and triglycerides. Bone marrow examination shows active Phagocytosis by macrophages and histiocytes. Treatment - MP pulse therapy and cyclosporine. (2) Chronic anterior uveitis: Most important complication of oligoarthritis. Often clinically silent and insidiously progressive. It is especially associated with +ve ANA. Every 3 monthly eye check up is suggested. (3) Growth disturbance, atrophy, contrature, and mis-alignment are major concerns in chronic arthritis. Successful control of ds and decreased use of steroids have reduced this complication (4) Cardiac disease: Pericardial involvement occurs almost exclusively with systemic-onset disease. Myocarditis and endocarditis are much rarer (5) Osteoporosis – JAO and growth arrest lines are common. Generalised OP may be observed, especially in patients with a polyarticular course. Other complicationsof JIA (6) Intercurrent infections (7) Anaemia (7) Secondary amyloidosis Summary • Diagnosis - typical clinical features, persistent swelling of 1 or more jts, before 16th b’day, without any clear cause. • Mimickers of JIA-septic arthritis, osteomyelitis, neoplasia ( ALL), neuroblastoma and lymphoma. • Subtypes -oligoarthritis, extended oligoarthritis, ERA, PsA, RF -ve & RF +ve polyarthritis and SOJIA. • No pathognomonic investigations for diagnosis. Laboratory investigations may be helpfulTo exclude differential diagnoses (mimickers) To sub-classify JIA To monitor disease • Multidisciplinary treatment is required including nursing staff, physiotherapists, occupational therapists and psychologists. • Treatment for JIA - usually proceeds in a stepwise escalating approach, beginning with NSAIDs and I/A steroids, early use of DMARDs for higher risk JIA groups. • Biologicals - Anti TNF, IL-1 and IL-6, for SOJIA which cannot be treated effectively with methotrexate. • Complications of JIA - chronic ant. uveitis, dental decay, anaemia, osteoporosis and growth disturbance. • Life threatening complications & adverse effects of Tx include sepsis, MAS, Reye syndrome and amyloidosis. Multiple choice questions (MCQs) MCQ - 1 Following is true about systemic onset JIAA. It usually occurs in children under 5 yrs of age B. Fever lasts for more then two weeks C. Only cervical lymphadenopthy is seen D. ANA is always present E. DIC is a recognized complication MCQ - 2 Following are true about oligo-articular JIA except– A. More common in females B. It is usually seen after the age of 8 years C. High risk for developing chronic iridocyclitis D. Associated with ANA positivity MCQ-3 All are true for Enthesitis related arthritis except A. Typically begins after age of 6 years B. It affects boys more than girls. C. Characterised initially by upper limb arthritis D. HLA-B27 found in 50% of patients E. ANA is negative. MCQ-4 All are complications of JIA except A. Intercurrent infections B. Pulmonary embolism C. Anaemia D. Osteoporosis E. Chronic anterior uveitis MCQ - 5 All are feutures of Macrophase activating syndrome except A. Hepatosplenomegaly B. Pancytopenia C. Abrupt decrease in ESR D. Low serum level of ferritin E. Elevated levels of liver enzymes and triglycerides.