Arthritis Cure An anti-inflammatory diet emphasizes increasing foods that reduce inflammation and minimizing foods that promote inflammation in the body.
1Division of Pediatric Rheumatology, Rainbow Babies & Children''s Hospital, University Hospitals Case Medical Center, 11100 Euclid Avenue, Cleveland, OH 44106, USA
Systemic juvenile idiopathic arthritis (sJIA) constitutes a small part of juvenile idiopathic arthritis (JIA), yet has a disproportionally higher rate of mortality. Despite being grouped under JIA, it is considered to be a multifactorial autoinflammatory disease. The objective of this paper is to review the epidemiology, pathogenesis, genetics, clinical manifestations, complications, therapy, prognosis, and outcome of sJIA. The presentation and clinical manifestations of sJIA have not changed much in the past several decades, but the collective understanding of the pathogenesis and the development of new targeted therapies (particularly the biologic agents) have transformed and improved the disease outcome for children with sJIA.
In 1897, Sir George Fredrick Still described 22 children, 12 of whom had a unique constellation of symptoms that included chronic arthritis, adenopathy, splenomegaly, and fevers . Initially bearing his name, and later known by other names (systemic juvenile rheumatoid arthritis, systemic juvenile chronic arthritis), this entity is now known as systemic arthritis . To allow for improved identification and research the International League of Associations of Rheumatology (ILAR) proposed a classification for JIA [2, 3]. To fulfill the criteria for systemic juvenile idiopathic arthritis (sJIA) a child must be under 16 years of age and have “arthritis in one or more joints with or preceded by fever of at least 2 weeks''s syndrome, or acute anterior uveitis, or a history of one of these disorders in a first-degree relative, (d) the presence of IgM rheumatoid factor on at least 2 occasions at least 3 months apart” . Despite being included under the inclusive umbrella of juvenile idiopathic arthritis (JIA), it is likely that sJIA is a different disease, for it appears to be unlike the other forms of JIA both in clinical presentation and its pathogenesis  (refer to section under pathogenesis). In the following sections we will review the epidemiology, pathogenesis, genetics, clinical manifestations, complications, therapy, prognosis, and outcome of sJIA.
By definition, sJIA can present at any point until the age of 16; however, in a recent study by Behrens et al., 74 out of 136 patients presented between 0–5 years of age, and age 2 was the most common age at presentation (n = 17) . Several studies showed that gender distribution is roughly equal [5, 6]. Ethnic composition seen in sJIA patients from Behrens et al.''s study, culturing healthy peripheral blood mononuclear cells with serum of sJIA patients caused an increase in IL-1 secretion; an increased production of IL-1β protein from mononuclear cells of active sJIA patients was also seen . IL-1β appears to have a pivotal role and may be responsible for the elevation in IL-6 .
IL-6 has an important role in affecting the systemic manifestations as well as arthritis in sJIA. Elevation of IL-6 in both peripheral blood and synovial fluid is seen; its expression seems to correlate with disease activity and parallel the fever curve . Acute phase reactants (such as C-reactive protein (CRP), serum amyloid A, fibrinogen, and ferritin) are stimulated by IL-6 . It appears to be responsible for the anemia seen in sJIA, as well as promote the production of hepcidin . Hepcidin is produced by the liver and is responsible for transmembrane iron transport; when elevated, it prevents the release of iron from the macrophages, hepatocytes, and enterocytes to the plasma, thus causing a decrease in serum iron levels . In addition, IL-6 may activate osteoclasts and cause osteoporosis, as well as instigate cartilage damage .
Other cytokines that may for 1 last update 2020/05/25 play a role in sJIA are interleukin-18 (IL-18) , myeloid-related protein (MRP)-8 and MRP-14 [29, 30], macrophage migratory inhibitory factor (MIF) , and interleukin 4-1098 T/G polymorphism . In addition, dysregulation in the expression of anti inflammatory cytokine interleukin-10 (IL-10) (via promoter polymorphism) seems to play an important part in sJIA . Other cytokines that may play a role in sJIA are interleukin-18 (IL-18) , myeloid-related protein (MRP)-8 and MRP-14 [29, 30], macrophage migratory inhibitory factor (MIF) , and interleukin 4-1098 T/G polymorphism . In addition, dysregulation in the expression of anti inflammatory cytokine interleukin-10 (IL-10) (via promoter polymorphism) seems to play an important part in sJIA .
Innate immune abnormalities in sJIA make it likely to be grouped with the autoinflammatory diseases , and indeed, according to the fourth international congress on the systemic autoinflammatory diseases, sJIA is a complex multifactorial autoinflammatory disease . The lack of strong major histocompatibility complex association can be seen both in sJIA and autoinflammatory diseases .
Pyrin (also known as marenostrin) is a 781 amino acid protein encoded by the familial Mediterranean fever gene (MEFV) found on chromosome 16p [36, 37]. Pyrin plays a role in the downregulation of inflammation [38, 39]. A registry of MEFV gene mutations is kept in the online database Infevers , and approximately 180 sequence alterations have been identified, out of which, 5 mutations are the most common ones . When MEFV gene mutations occur, pyrin''s disease [46–49]. A higher rate of MEFV gene mutations was seen in patients with sJIA in comparison with ethnically matched population (P < 0.01) . Interestingly, even when only one allele is affected by mutations or polymorphism, subclinical inflammation can be seen [50, 51]. It is possible that mutations in the MEFV gene prompt a carrier to either develop sJIA or have a more severe course. In a recent study by Ayaz, the MEFV mutation frequency in sJIA patients was seen in 14.28% (significantly higher than in the general population (P < 0.01)); the most common mutation was M694, which appeared in frequency of 10% .
It has been postulated that a genetic association between sJIA and macrophage activation syndrome (MAS) exists via a mutated perforin gene (PRF1) [52–54] and polymorphism of both MUNC13-4  and interferon regulatory factor 5 (IRF5)  genes. However, Donn et al. studied genes known to be associated with the familial form of hemophagocytic lymphohistiocytosis (HLH) (HLH and MAS will both be discussed more under the section on complications) and did not see an increased susceptibility to sJIA . Only a limited number of genes were analyzed, and furthermore, the genetic association of MAS in an existing sJIA patient was not studied .
Arthritis Curehow to Arthritis Cure for The most common presenting feature is fever, followed by arthritis and rash. Less frequent are lymphadenopathy, pericarditis, and hepatosplenomegaly [5, 58]. Most patients present with laboratory findings indicative of inflammation: elevated erythrocyte sedimentation rate (ESR) and CRP [5, 58], leuko- and thrombocytosis, and elevation in liver transaminases, as well as anemia . Elevation of D-dimers [5, 59], ferritin, and aldolase  is seen.
Some patients''s study showed different patterns. The classic pattern is only seen in 37% of the patients during initial presentation; others exhibit morning fevers (12%), bi-daily fevers (15%), intermittent fevers (27%), and unremitting fevers (5%) , as well as not reaching 39°C [5, 62]. In addition to the fevers, some children rapidly defervesce and attain subnormal temperatures [8, 64, 65]. While the child is febrile, other symptoms such as arthritis, rash or serositis can worsen and cause significant disturbance of daily life; however, once the child has defervesced, it is not unusual to see a resumption of regular activities [8, 62, 66].
Arthritis Curehow to Arthritis Cure for Arthritis is the second most common presenting symptom , and arthralgias can precede the arthritis [65, 66]. According to Behrens et al., 88% of children presented with arthritis . In those cases where arthritis was not found initially, it typically appeared within a few months; infrequently the arthritis will not present until several years later . In Behrens et al.''s study 10% of the patients presented with pericarditis . According to Modesto et al., serositis (not specified) was seen in 14% of those who had good prognosis and 16% of those with bad prognosis . It is typically recurrent but benign . It often develops early in the course of sJIA and can manifest itself before the appearance of arthritis [8, 66, 87]. Children who have pericarditis may have nonspecific findings such as tachycardia and dyspnea, but may also have a friction rub . Pericarditis may be an ominous sign of evolving myocarditits, which has more serious and potentially fatal complications of cardiomegaly, congestive heart failure, and arrhythmias [65, 88–90]. In a 1992 study by Goldenberg et al., which investigated symptomatic cardiac manifestations in JRA, 13 out of 172 patients were identified (11 of whom had sJIA); from the sJIA patients, pericarditis was recorded in 5, myopericarditis in 4 and isolated myocarditis in 2 patients . Asymptomatic pleuritis and pleural effusions can present together with pericarditis or independently [8, 65].
Peritonitis is a rare manifestation of sJIA and was seen in two children, one during the first week of presentation, and the other 10 years after diagnosis .
Arthritis Curehow to Arthritis Cure for Although rare, central nervous system manifestations such as seizures, meningismus, as well as irritability and decreased level of consciousness were previously described . Ocular manifestations can be seen in sJIA, and uveitis is one of the complications . A case report by Ishihara et al. described a patient with sJIA who developed bilateral panuveitis 3 years after her initial presentation . In addition, Brown''s by Wagener et al. . In a cross-sectional study, Van Der Net et al. described restrictive pulmonary function in 8 out of 17 patients showing decreased total lung capacity; in 2 additional patients normal (yet lower) total lung capacity was seen . Obstruction was not seen, as the Tiffeneau index (FEV1/FVC × 100%) was > 83% in all of the patients . Interstitial pulmonary disease was reported by Athreya et al. . Pulmonary hypertension was described in one case report , and pulmonary interstitial and intra-alveolar cholesterol granulomas were described in a 2001 case report .
The clinical presentation of sJIA and Kawasaki disease (KD) can be similar in young children. In a recent study from Binstadt et al., 5 out of 12 sJIA patients who had an echocardiogram that fully evaluated the coronary arteries on initial presentation had coronary artery dilation, and out of these, 2 patients had initially fulfilled the KD criteria . Interestingly, a study by Maeno et al. showed that significant elevation of IL-18 levels was seen in sJIA, but not in KD or other types of JIA .
With nonspecific clinical and laboratory findings, the differential diagnosis of sJIA is extensive and should include infectious as well as post infectious etiologies, connective tissue diseases, vasculitis, malignancies, and autoinflammatory syndromes .
Serum amyloid A is an acute phase reactant which is elevated with inflammatory processes. It is the precursor for serum amyloid A protein [104, 105]. Amyloidosis is one of the most severe complications of sJIA. For unknown reasons, amyloidosis tends to be very rare in North America and yet affects a larger percentage of individuals in the UK and Turkey (7.4% and 16%, resp.) [106, 107]. Deposition of the protein has an effect on vital organs such as the kidney, liver, gastrointestinal tract, and heart . Upon biopsy of rectal mucosa, subcutaneous fat, gum, or kidney, amyloidosis can be histologically recognized by using Congo red stain, which reveals eosinophilic deposition; when employing polarized light, the characteristic apple-green birefringence surfaces [105, 108, 109]. The first clinical sign of amyloidosis is proteinuria, but it is often missed and nephrotic syndrome is seen [8, 105]. Other symptoms that may suggest amyloidosis are: hypertension, hepatospenomegaly, and abdominal pain [8, 105]. Unless the inflammatory process of sJIA is successfully suppressed and amyloidosis reverses, death from progressive renal failure in those children with amyloidosis can result [8, 105]. Immonen et al. examined the long-term outcome of 24 patients with amyloidosis; sJIA was seen in 11/24 patients (46%). The overall 5 year survival rate was 88%, and 10-year survival rate was 75%. Out of the 24 patients with all subclasses of JIA, 10 died. Although the mortality for the different types of JIA was not specified, overall, a higher mortality was seen in patients who were treated solely with corticosteroids, while those who were treated with disease modifying antirheumatic drugs and/or cytotoxics had a better survival (P = 0.001) .
In 1985 Hadchouel et al. described a life-threatening complication of sJIA  for which the term MAS was later coined . Uninhibited production and activation of both macrophages and T lymphocytes cause fever, rash, pancytopenia, hepatic insufficiency, coagulopathy, lymphadenopathy, and neurological dysfunction [113, 114]. MAS is not a unique entity, but rather a term used to describe a form of secondary HLH when it is seen in a rheumatic illness [115–117]. The incidence of MAS in the context of sJIA is estimated to be anywhere from 6.7%–13% [60, 118], and mortality rate ranges between 8–22% [118, 119]. As the symptomology of MAS is almost identical to that of sJIA, it is very difficult to diagnose. Some of the laboratory findings that are useful in distinguishing the two are the presence of cytopenias and normal ESR noted in MAS . Nevertheless, it was recently shown that multiple sJIA patients had evidence of hemophagocytosis on bone marrow examination but did not have any clinical findings . It is now believed that sJIA and MAS are possibly the two extremes of similar entities, where sJIA represents hidden or inactive MAS [4, 5].
Historically, the management of sJIA included the use of nonsteroidal antiinflammatory drugs (NSAIDs), intravenous immune globulin (IVIG), corticosteroids, methotrexate, anti-TNF, cyclosporine, thalidomide, cyclophosphamide, and autologous stem cell transplantation [42, 120–123]. IVIG was initially encouraging, but in further studies, it was noted to perhaps be useful only for particular subsets of children with early systemic disease . Although showing significant efficacy in other subtypes of JIA, methotrexate did not show adequate response in sJIA [125–127]. Anti-TNF agents were shown to have only a partial response [128–132]. With the recent expanding understanding of sJIA pathogenesis, the treatment has changed tremendously. A more targeted therapy in the form of biologic blocking agents transformed the treatment of sJIA [133, 134].
In sJIA, NSAIDs are used for the management of pain, stiffness, and fever . Historically, aspirin was used; however, the risk of intoxication  as well as development of Reyes syndrome promoted the replacement of aspirin with other NSAIDs [136–139]. Ibuprofen, meloxicam, naproxen, tolmetin, and celecoxib are approved by the Food and Drug Administration (FDA) for treatment of JIA . Gastrointestinal adverse reactions such as gastritis and duodenitis are common [141, 142]. Pseudoporphyria associated with naproxen therapy can be seen in those children with light complexion and light hair. As permanent scarring may occur, awareness of this adverse reaction is important [143–145].
Although not considered to be disease modifying, systemic corticosteroids are often used when patients experience a preponderance of systemic features . Kimura et al. studied the efficacy and side effects of high-dose alternate day prednisone and concluded that it was a valuable therapy with minimal adverse reactions .
Intravenous pulsed methylprednisolone is also useful in treating sJIA patients. In Adebajo and Hall''s 2008 study, 10/22 (45%) of patients responded well to the therapy, 11/22 (50%) had incomplete response or no response to the therapy, and 1/22 (5%) could not be classified as either . In Lequerré et al., at the last follow up, complete response was seen in 4/20 (20%), partial response seen in 5/20 (25%), and no response seen in 8/20 (40%) of patients (of the 3 patients not accounted for, 1 had a complete response at 3 months but did not have a reported follow up, and two were seen at two months with no response and did not have a reported follow up) . In Ohlsson et al.''s 2009 study, 8/33 (24%) of patients did not have a good response . A recent multicenter report of 46 patients treated with anakinra showed significant improvement; by 1 month of treatment, 86% of patients experienced abatement of fever and rash, and 84%, 63%, 83% and 71% of patients had normalization of CRP, ESR, ferritin levels, and platelet count respectively . In that study complete response occurred only in 59% of the patients, partial response in 39% of the patients, and in 2% lack of response . Two theories have risen to explain the different therapeutic response. Gattorno et al. postulated the existence of further classes in sJIA , and Nigrovic et al. hypothesized less efficacious blockade of IL-1 in an established disease secondary to either chronic inflammation (derived from ample supply of IL-1), or secondary to independent action of IL-17, possibly causing arthritis .
Arthritis Curehow to Arthritis Cure for Rilonacept, the IL-1R-IL1RacP-Fc fusion protein (also known as IL-1 trap), showed immense for 1 last update 2020/05/25 response in an open label pretrial . The selective IL-1β antibody canakinumab treats genetic fever syndromes, thus identifying this agent as a potential therapeutic modality for sJIA .Rilonacept, the IL-1R-IL1RacP-Fc fusion protein (also known as IL-1 trap), showed immense response in an open label pretrial . The selective IL-1β antibody canakinumab treats genetic fever syndromes, thus identifying this agent as a potential therapeutic modality for sJIA .
Tocilizumab is a humanized monoclonal antibody, targeting both membrane bound and soluble IL-6 receptors . By binding to these receptors, signal transduction through glycoprotein 130 is inhibited . In 2003, Yokota reported the first encouraging use of IL-6 inhibition in children . In 2005, a phase II trial with tocilizumab showed JIA 30%, 50%, and 70% improvement according to a core set of response variables in 10/11 (90.9%), 10/11 (90.9%), and 7/11 (63.6%) patients, respectively . This definition of improvement was based upon the ACR Pediatric (ACR Pedi) 30 criteria, alternatively known as JRA, JIA, or Giannini''s long-term extension, abatacept was again reported to have good response rate; the ACR Pedi 30, 50, 70, 90 and inactive disease response rate in patients with sJIA without systemic manifestations were 88%, 88%, 63%, 13%, and 25% correspondingly . In a later report that year, Ruperto et al. discerned improvement in health-related quality of life (HRQOL) in JIA patients treated with abatacept (in which about 20% of the patients that were studied had sJIA) .
An anecdotal report of a combination therapy of anakinra and abatacept in 4 children with recalcitrant sJIA described improvement of their symptoms, with no significant adverse reactions .
There are three different types of antitumor necrosis factor (anti-TNF) therapies: etanercept: a soluble TNFα receptor [169, 179, 180], Infliximab: a chimeric monoclonal TNFα antibody, and Adalimumab: a humanized monoclonal antibody.
The results from Lovell et al.'' flare rate between placebo and etanercept therapy were encouraging, with 7/8 (88%) patients on placebo having a flare, and 4/9 (44%) of those on etanercept having a flare (statistically the 1 last update 2020/05/25 significant P < 0.001) . Several later studies show that patients with sJIA appear to have only partial response to anti-TNF agents [128–132]. The results from Lovell et al.'' flare rate between placebo and etanercept therapy were encouraging, with 7/8 (88%) patients on placebo having a flare, and 4/9 (44%) of those on etanercept having a flare (statistically significant P < 0.001) . Several later studies show that patients with sJIA appear to have only partial response to anti-TNF agents [128–132].
In 2003 Lovell et al. published interim results from an ongoing multicenter study examining etanercept, and reported improvement rates in JRA (30%, 50% and 70%). In the per protocol group at the end of the 2nd year, 30% improvement was seen in 10/12 patients (83%), 50% improvement was seen in 9/12 patients (75%), and 70% improvement was seen in 8/12 patients (67%); in their modified intent-to-treat group (which included the patients who discontinued therapy) 30% improvement was seen in 10/17 patients (59%), 50% improvement was seen in 9/17 patients (53%), and 70% improvement was seen in 8/17 patients (47%) . In Horneff et al.''s criteria of 30%, 50%, and 70% improvement was seen in 48%, 33%, and 11% of the patients, respectively, after 1 month of treatment with etanercept, and after 3 months of treatment, improvement was seen in 63%, 39%, and 24% . In Kimura et al.'' 2009 study, patients were treated initially with etanercept, but if improvement was not seen, patients were switched to therapy with either infliximab or adalimumab. The ACR pedi 30, 50, 70, and 90 criteria were used to assess clinical improvement and were seen in 35 (78%), 28 (62%), 21 (47%), and 14 (31%) of patients, respectively . See Arthritis Curehow to Arthritis Cure for Table 2. In Quartier et al.''s criteria of 30% improvement seen in 48% of patients.
(ii) Giannini''s criteria of 70% improvement seen in 11% of patients.
At 3 months:
(i) Giannini''s criteria of 50% improvement seen in 39% of patients.
(iii) Giannini''s analysis. Out of the 43 patients in this group, 12 patients had systemic JRA.
Arthritis Curehow to Arthritis Cure for ∗ ∗Modified intent-to-treat group consisted of 51 patients (with pauciarticular, polyarticular or systemic JRA): 43 were included in the per protocol group, 7 withdrew secondary to an inadequate clinical response (of these, 4 had systemic JRA), and 1 withdrew secondary to an adverse reaction (that patient had systemic JRA). Out of the 51 patients in this group, 17 patients had systemic JRA.
In a 2003 Lovell et al.''s 2004 study, 17 of the 66 sJIA patients enrolled withdrew from the trial, where inefficacy of therapy was the reason for discontinuation in 14 out of the 17 patients, adverse effects were seen in 2 patients and 1 patient withdrew for other reasons . In Kimura et al.''s 2009 study looked at length of anti-TNF therapy usage (either etanercept or infliximab). At 24 and 48 months 46% and 76% of patients, respectively, had discontinued their medications. Inefficacy was the most common reason for discontinuation in the sJIA group .
In Katsicas and Russo'' 2009 study between remission and both the absence of systemic manifestations at the onset of anti-TNF therapy and improvement after 3 months of therapy. In that study 64% (29/45) of patients showed an improvement after 3 months of treatment, and 73% (33/45) of patients displayed an improvement after 6 months .
Rituximab is a chimeric monoclonal antibody against CD20, targeting B cells. Wouters et al. described a higher B-cell activity in all types of JIA, including sJIA . There are several case reports detailing treatment of sJIA with rituximab. Kasher-Meron et al. describe an 18-year-old female with a 12-year history of sJIA that was recalcitrant to therapy that responded well to therapy with rituximab . A case series by Narváez et al. described three adult patients with unrelenting sJIA (duration of disease between 18–27 years), all of whom had noteworthy improvement with rituximab therapy; with the exception of one patient with hypersensitivity reaction, no other significant adverse reactions were seen . Lastly Feito and Pereda described an 8-year-old female that responded well to rituximab, in both systemic manifestations and articular manifestations .
Cyclosporine is an immunomodulator that inhibits the synthesis of IL-1, IL-2, TNF-γ, and α-interferon [188–190]. The results of a 10-year prospective study looking at the efficacy of cyclosporine A showed benefit for some children with sJIA, but for the majority complete remission was not achieved . In a later surveillance study, out of those patients who were still receiving cyclosporine at their last reported visit, only 5% have achieved full clinical response, while 63% had mild to moderate activity and 32% had severe uncontrolled disease . Associated adverse reactions reported are hypertrichosis, elevated serum creatinine levels, gingival hyperplasia, gastrointestinal irritation, and hypertension .
Thalidomide prevents cytokine synthesis by disturbing mRNA synthesis rather than blockade , and is a known anti-inflammatory agent that suppresses angiogenesis, cell adhesion molecule expression, TNF-α, IL-1, IL-6, and nuclear factor-κG [194–196]. In 2002, Lehman et al. reported on 2 children with intractable sJIA who were treated with thalidomide therapy and had significant improvement . In 2004, Lehman et al. reported of 13 additional children for 1 last update 2020/05/25 who were treated with thalidomide. A response was seen in 11 children, and 10 of them had JRA improvement scores ≥50% in concordance with the preliminary definition of improvement in juvenile arthritis [120, 170]. Statistically significant decrease in prednisone dosage, decrease in ESR, and increase in hemoglobin level were seen . In 2007 a 3-patient case series was reported by Garcίa-Carrasco et al., where after therapy with thalidomide, 3 recalcitrant patients entered remission .Thalidomide prevents cytokine synthesis by disturbing mRNA synthesis rather than blockade , and is a known anti-inflammatory agent that suppresses angiogenesis, cell adhesion molecule expression, TNF-α, IL-1, IL-6, and nuclear factor-κG [194–196]. In 2002, Lehman et al. reported on 2 children with intractable sJIA who were treated with thalidomide therapy and had significant improvement . In 2004, Lehman et al. reported of 13 additional children who were treated with thalidomide. A response was seen in 11 children, and 10 of them had JRA improvement scores ≥50% in concordance with the preliminary definition of improvement in juvenile arthritis [120, 170]. Statistically significant decrease in prednisone dosage, decrease in ESR, and increase in hemoglobin level were seen . In 2007 a 3-patient case series was reported by Garcίa-Carrasco et al., where after therapy with thalidomide, 3 recalcitrant patients entered remission .
In the recent 2011 American College of Rheumatology recommendations for the treatment of sJIA, the recommendations were made by identifying the patient as belonging to one out of two distinct clinical groups: active systemic features (without active arthritis), or active arthritis (without active systemic features), and also by disease activity level and by prognosis. For those patients with both active systemic features and active arthritis, a recommendation was not made, but use of the two recommendations was suggested. Furthermore, recent therapeutic agents, such as IL-6 inhibitors and other IL-1 inhibitors besides anakinra were not included the recommendations as they were not available .
For systemic arthritis with active systemic features but no arthritis, initiating NSAIDs, systemic glucocorticoids, or anakinra as initial therapy is dependent on disease activity and prognostic features. Patients with low disease activity and good prognostic features are recommended the treatment of NSAIDs, followed by glucocorticoids and anakinra. NSAIDs may be omitted for those patients with either poor prognostic features or high disease activity. For patients with high disease activity and without poor prognostic features, initial therapy with systemic glucocorticoids followed by anakinra when not responding well is recommended. For patients with poor prognostic features, initial therapy may be either systemic glucocorticoids or anakinra . Methotrexate was deemed inappropriate for this group, and both thalidomide and calcineurin inhibitors were of uncertain benefit .
Treatment recommendations for systemic arthritis with active arthritis but without active systemic features include up to 1 month of NSAIDs with glucocorticoid joint injections. If no improvement or worsening, methotrexate was the next therapy. After 3 months of methotrexate therapy, dependent on disease activity, the patient can start on either TNFα inhibitor or anakinra. After 4 months of TNFα therapy, if the disease activity is still high or moderate (but with poor prognosis), abatacept was recommended. Calcineurin inhibitors were found to be unsuitable for this group of patients .
The course and outcome of sJIA can vary considerably, ranging from a monocyclic course with good outcome, to a more complicated one which involves considerable morbidity or mortality. In approximately half the patients with sJIA, a monocyclic course is seen, and complete recovery with minimal physical limitations can be achieved within 2–4 years [42, 69, 200]. Waning flares of systemic involvement and mild arthritis can be seen in those with relapsing course . Some patients achieve resolution of their systemic features, but suffer from significant persistent arthritis which tends to resolve after about 5 years . However, approximately 30% of the patients suffer from devastating destructive chronic polyarthritis that is responsible for most of the morbidity and account for the worst prognosis in this disease [69, 202]; resolution of the arthritis does not usually occur by adulthood . These patients tend to have more severe systemic manifestations , and for about 23–30%, systemic features persist for more than 10 years after initial presentation [204, 205].
Systemic manifestations 6 months following presentation, thrombocytosis , hip involvement in the setting of polyarthritis, and generalized lymphadenopathy in those less than 8 years of age  are predictors of poor outcome. Several studies have attempted to stratify the risk for development of destructive arthritis suggest that early course arthritis of the hips, cervical spine, and small joints of the digits can indicate higher risk [203, 207]. In the past, amyloidosis was a significant risk factor for death , but according to Immonen et al., new onset of amyloidosis in sJIA was not seen in Finland since 1991 . MAS is a significant complication, and mortality was seen in 8–22% [118, 119]. Lastly, psychological complications such as depression, anxiety, and social isolation are important patient outcomes .
The clinical symptoms of sJIA have not changed significantly from 1897 when it was first described by Still. The recognition of the unique nature of sJIA in comparison to other types of JIA as well as an increased collective understanding of the pathogenesis, instigated significant advancement in treatment options offered to these children. IL-1 blockade revolutionized the treatment and outcome for sJIA patients. With the discovery of novel and targeted biologics, the pediatric rheumatologist is presented with several choices. In a patient who presents initially with arthritis and systemic features, NSAIDS, steroids, and IL-1 blockers are reasonable considerations depending upon the severity of symptoms and the need for a prompt remission of symptoms. After the initial presentation, for those patients with primarily systemic features, we would continue IL-1 blocker and taper steroids as tolerated. For milder cases with systemic features, thalidomide remains an option. Tocilizumab which was recently approved for sJIA is a choice for those patients that have more severe disease or fail to respond to IL-1 blocking agents, but it remains an indefinite commitment to every two-week infusions at present. For children with a predominantly polyarticular course who no longer have fever and rash, we would consider anti-TNF agents and methotrexate. An individualized approach for each patient is recommended.
The newly gained knowledge and the development of new treatments are changing the lives of children who are suffering from sJIA today. Their prognosis and disease outcome are much better than in previous generations. There is still ample knowledge to be learned in order to create better and more effective therapies.