Systemic onset juvenile rheumatoid arthritis (formerly called Still's disease) is a subset of juvenile rheumatoid arthritis (JRA) that describes patients with: Intermittent fever +/- rash Arthritis Children with this illness comprise between 10 and 15 percent of all cases of JRA.
Disseminated intravascular coagulation (DIC) or Macrophage activation syndrome (MAS) May occur within the first few days or weeks following: 1. Initiation of therapy with NSAIDs or gold salts 2. Viral and bacterial infections Or may occur without any evident initiating event.
DIAGNOSIS: A diagnosis of exclusion Combination of intermittent daily fevers greater than 38.5°C and arthritis For at least six weeksMay be delayed Hallmark
Laboratory findings: Acute phase response Neutrophilic leucocytosis: count in the 20,000 to 30,000/mm3 range Marked reactive thrombocytosis Anemia: commonly present and often profound Elevated serum ferritin levels Minor transaminitis
SOJRA may be the most difficult form of JRA to diagnose for the following reasons:
First: Arthritis may not be evident early in the course of the disease. Arthritis is important to make a definite diagnosis
Second: Children often appear quite ill with: High spiking fevers Rashes Markedly elevated WBC counts Anemia Hence, initially thought to have an infection But, with no response to antibiotics And with >6weeks duration * *
An ill child with nausea, fever, and an erythematous rash over the extremities Viral exanthems in childhood Parvovirus Rubella EB rarely HBV
DD of polyarthritis and a maculopapular rash Connective tissue disease: Infections: Drug-induced: e.g. SLE, Still’s, dermatomyositis, vasculitis Viral: hepatitis B, rubella, parvovirus, EB virus Bacterial as meningococcal infection, leptospirosis Miscellaneous: Angioimmunoblastic lymphadenopathy Erythema multiforme, serum sickness
Third: Children may have: Fevers Markedly elevated WBC counts Anemia Lymphadenopathy Hence, leukemia considered Clues to differentiation include
Systemic onset JRA is not associated with: Thrombocytopenia Lymphocytosis Extreme pain* LN biopsy shows reactive hyperplasia
c Five-year old boy with a 6 months’ history of fever ( 40 o C), weight loss and polyarthritis On examination: ill, pale and irritable, got apprehensive on any attempt to examine his joints. He had generalized lymphadenopathy. There was swelling and tenderness of his wrists, elbows, knees, ankles and feet joints.
His labs showed ESR 140 Hb 2.3; MCV 56 WBC 2.9 Platelets 50 Serum albumin 2.1 ALT, AST: normal Urine: free ANA negative
Treatment: NSAIDs: Indomethacin Corticosteroids: used judiciously to minimize toxicity (below 0.5 mg/kg per day of prednisone or its equivalent) and the duration of therapy should be less than six months Methotrexate with a usual maximum oral dose of 15 mg per week.
Course and prognosis: Highly variable, but in general: The child who appears well after six months has a substantial probability of remaining well. Poorer functional outcomes may occur in those with more than six months of fever, thrombocytosis, or corticosteroid therapy