Other Rheumatologic Diseases

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Other Rheumatologic Diseases




Systemic-Onset Juvenile Idiopathic Arthritis (SoJIA; Still’s Disease) and Adult-Onset Still’s Disease (AoSD)



Among the major types of juvenile idiopathic arthritis (JIA; formerly juvenile rheumatoid arthritis [JRA]), cutaneous manifestations are most common in SoJIA, psoriatic arthritis (see Chapter 6), and rheumatoid factor (RF)-positive polyarthritis (rheumatoid nodules and other findings similar to rheumatoid arthritis [RA]; see below).


SoJIA can develop at any age prior to 16 years and affects both sexes equally; AoSD has peaks in the second and fourth decades and affects women more often than men.


Both SoJIA and AoSD are characterized by daily spiking fevers (especially in the late afternoon/early evening) accompanied by an evanescent eruption of salmon-pink macules and slightly edematous papules and plaques (Fig. 37.1A,B); these lesions are usually asymptomatic and favor sites of pressure or trauma, often occurring in a linear array.



Less common skin findings include periorbital edema and persistent pruritic papules and plaques that are scaly, violaceous to reddish brown in color, and linear in configuration (Fig. 37.1C).


Additional features include a prodromal sore throat and arthralgias/myalgias, arthritis (usually polyarticular; ± carpal ankylosis in AoSD), lymphadenopathy, hepatosplenomegaly, and serositis; occasionally patients may develop macrophage activation syndrome (also characterized by markedly elevated ferritin).


Leukocytosis with neutrophilia, thrombocytosis, anemia, elevated ESR/CRP, and extremely high serum ferritin levels (e.g. >4000 mg/ml) are common laboratory findings, whereas ANA and RF are usually absent.


DDx: infections (e.g. parvovirus B19), rheumatic fever, serum sickness-like reactions, urticarial vasculitis, Schnitzler’s syndrome (in adults; see Chapter 14), other autoimmune connective tissue diseases, hereditary periodic fever syndromes (see Table 3.2).


Rx: NSAIDs (for mild disease), systemic CS, methotrexate, antagonists of IL-1 (e.g. anakinra, canakinumab) or IL-6 (e.g. tocilizumab), and TNF inhibitors (the latter especially for arthritis).


Apr 22, 2016 | Posted by in Dermatology | Comments Off on Other Rheumatologic Diseases

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