Retrospective study of 61 patients with adult-onset Still’s disease admitted with fever of unknown origin in China

Adult-onset Still's disease and fever of unknown origin in India

Despite an essential differential diagnosis for fever of unknown origin (FUO) in young adults, adult-onset Still's disease (AOSD) is infrequently considered and remained underdiagnosed in low-middle-income countries. The present study analyzed the clinical, serological, radiological, and pathological characteristics of AOSD presented as FUO in India. A hospital-based retrospective study of patients aged > 13 years admitted with FUO and later diagnosed with AOSD in Postgraduate Institute of Medical Education and Research, Chandigarh (India), was conducted between January 2014 and December 2020. Petersdorf and Beeson's criteria were used to define FUO. The diagnosis of AOSD was made based on Yamaguchi's criteria. Twenty-seven patients (median age 26 years, 14 females) were enrolled. All presented with intermittent fever with a median duration of 10 weeks. The typical features of AOSD at admission were arthralgia (n = 24), hepatosplenomegaly (n = 21), spiking fever ≥ 39 °C (n = 19), lymphadenopathy (n = 18), typical rash (n = 17), and sore throat (n = 11). Leukocytosis (n = 25) and neutrophilia (n = 19) were frequent. Hyperferritinemia was universal (range, 700-145,003 ng/ml; ≥ 2000, n = 23). At admission, AOSD was suspected in only nine FUO cases, while tuberculosis (n = 16), undifferentiated connective tissue disorder (n = 14), and lymphoproliferative disorder (n = 11) were common diagnostic possibilities. Crispin et al. clinical scale detected AOSD in only 15 (55.5%) FUO patients. Whole-body imaging (n = 27), including fluorodeoxyglucose positron emission tomography (n = 12), demonstrated reticuloendothelial organ-system involvement and serositis. Seventeen (63%) patients had macrophage activation syndrome at the time of AOSD diagnosis. AOSD FUO presents with typical but nonspecific features; thus, early differentiation from common causes (e.g., tuberculosis, lymphoma) is difficult. Macrophage activation syndrome is common in AOSD with FUO presentation.

Proposal of a new diagnostic algorithm for adult-onset Still's disease

OBJECTIVE

This study was performed to develop a new diagnostic algorithm for adult-onset Still's disease (AOSD).

METHODS

We conducted a multicenter prospective nationwide case-control study in tertiary Internal Medicine, Rheumatology, and Infectious Diseases departments, to include successively patients with suspected AOSD based on the presence of two or more major criteria of Yamaguchi and/or Fautrel classifications. Patients were classified as AOSD or controls according to a predefined procedure. A receiving operating characteristic curve was used to determine the best cutoff value of the points-based score for disease classification. A diagnostic algorithm was developed to help the physician in the diagnostic approach.

RESULTS

A total of 160 patients were included, 80 patients with AOSD and 60 controls with different diagnoses. Twenty patients with incomplete data were excluded. In the multivariate analysis, 6 items remained independently associated with AOSD diagnosis: typical rash (OR: 24.01, 3 points), fever ≥ 39 °C (OR: 17.34, 3 points), pharyngitis (OR: 10.23, 2 points), arthritis (OR: 9.01, 2 points), NLR ≥ 4 (OR: 11.10, 2 points), and glycosylated ferritin ≤ 20% (OR: 1.59, 1 point). AOSD should be considered if the patient satisfies 7 points with a sensitivity of 92.5%, specificity of 93.3%, and accuracy of 92.8% (area under the curve (AUC): 0.97 [95% CI: 0.94-0.99]). The present points-based score was more accurate and sensitive than the Yamaguchi classification (78.8%, 92.5%, p = 0.01) and Fautrel classification (76.3%, 92.5%, p = 0.004). A typical rash associated with a points-based score ≥ 7 points leads to a very likely disease.

CONCLUSION

The proposed new algorithm could be a good diagnostic tool for adult-onset Still's disease in clinical practice and research. Key Points • A diagnostic algorithm was performed to help the physician in the diagnostic approach of AOSD. • The points-based score included in this algorithm had a high sensitivity and accuracy. • This diagnostic algorithm can be useful in the clinical research.

New insights on multigenic autoinflammatory diseases

Autoinflammatory diseases are disorders of the innate immune system, which can be either monogenic due to a specific genetic mutation or complex multigenic due to the involvement of multiple genes. The aim of this review is to explore and summarize the recent advances in pathogenesis, diagnosis, and management of genetically complex autoinflammatory diseases, such as Schnitzler's syndrome; adult-onset Still's disease; synovitis, acne, pustulosis, hyperostosis, osteitis syndrome/chronic recurrent multifocal osteomyelitis/chronic non-bacterial osteomyelitis; Adamantiades-Behçet's disease; Yao syndrome; and periodic fever with aphthous stomatitis, pharyngitis, and adenitis syndrome. The PubMed database was screened for relevant articles using free text words and specific search strings. The search was limited to English-language articles, reporting the results of studies in humans, published through March 2021. Evidence from literature suggest that these rare multigenic autoinflammatory diseases can present with different clinical features and the diagnosis of these diseases can be challenging due to a combination of nonspecific manifestations that can be seen in a variety of other conditions. Diagnostic delays and disease complications may occur due to low disease awareness and the lack of pathognomonic markers. The pathogeneses of these diseases are complex and in some cases precise pathogenesis is not clearly understood. Conventional treatments are commonly used for the management of these conditions, but biologics have shown promising results. Biologics targeting proinflammatory cytokines including IL-1, IL-6, TNF-α, IL-17A and IL-18 have been shown to ameliorate signs and symptoms of different multigenic autoinflammatory diseases.

Validation of the neutrophil-to-lymphocyte ratio as a new simple biomarker of adult onset Still's disease: A STROBE-Compliant prospective observational study

This study was performed to investigate the role of neutrophil-to-lymphocyte ratio (NLR) in the diagnosis of adult onset Still disease (AOSD) and its performance to improve the sensitivity of the classifications criteria (Yamaguchi and Fautrel Classifications). We conducted a multicenter prospective nationwide case-control study in Internal medicine, Rheumatology and Infectious disease departments, to include successively patients with suspected AOSD (2 or more major criteria of Yamaguchi or Fautrel classifications). All clinical and biological features were collected in a consensual and standardized clinical assessment at baseline and during follow-up. A receiving operating characteristic (ROC) curve was used to reassess the cutoff value of NLR. After determination of the cutoff value for NLR by ROC curve, 2 composite sets (Yamaguchi classification + NLR as a major criterion and Fautrel classification + NLR as a major criterion) were performed and evaluated. One hundred sixty patients were included, 80 patients with AOSD and 60 controls with different diagnoses. Twenty patients with incomplete data were excluded. The cutoff value for NLR equals 4 (area under the curve, AUC: 0.82). The NLR was ≥ 4 in 93.7% (75/80) of AOSD patients with a sensitivity of 93.8% and specificity of 61.7%. The association of NLR as a major criterion with the classification of Yamaguchi or Fautrel improved their sensitivity, respectively for Fautrel (76.3% to 92.5%, P = .004) and Yamaguchi (78.8% to 90%, P = .05). This study validates the NLR as a good simple biomarker of AOSD with a cutoff value of 4 and high sensitivity (93.8%). The addition of NLR (NLR ≥ 4) as a major criterion to the classifications (Yamaguchi and Fautrel) improved significantly their sensitivity and accuracy.

Adult-onset Still's disease in focus: Clinical manifestations, diagnosis, treatment, and unmet needs in the era of targeted therapies

BACKGROUND

Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder of unknown etiology, characterized by a clinical triad of high spiking fever, arthralgia (± arthritis), and evanescent skin rash. Management of AOSD poses several challenges, including difficulty in diagnosis and limited therapeutic options. In this review, we examined whether AOSD and systemic juvenile idiopathic arthritis (SJIA) represent a continuum of the same disease. We also explored the latest available evidence related to prevalence, clinical and laboratory manifestations, complications, diagnostic challenges, novel biomarkers, and treatment options in the era of biologics and identified the unmet needs of patients with AOSD.

METHODS

A comprehensive systematic literature search was performed in the Embase and MEDLINE (via PubMed) literature databases. The search was limited to human studies published in English from inception up to March 2020. Additionally, abstracts presented at various conferences were screened and hand searches were performed. Publications were processed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 123 publications were identified through the literature search, majority of which were case series and retrospective observational studies. AOSD and SJIA are widely considered part of the same disease spectrum owing to similarities in their clinical and biological features. The clinical presentation of AOSD is highly variable, accompanied by a broad spectrum of disease manifestations. Recent evidence suggests that the AOSD disease course can be classified into two distinct categories: "systemic" and "articular." Furthermore, AOSD patients may experience various life-threatening complications, such as macrophage activation syndrome - reported in as high as 23% of AOSD patients and considered to be the most severe complication characterized by a high mortality rate. The ambiguity in presentation and lack of serologic markers make the diagnosis of AOSD difficult, often leading to a delay in diagnosis. Given these limitations, the Yamaguchi and Fautrel criteria are the most widely used diagnostic tools in clinical practice. It has been observed that a clinical diagnosis of AOSD is generally reached by exclusion while investigating a patient with fever of unknown origin. Recent advances have demonstrated a major role of proinflammatory cytokines, such as interleukin (IL)-1, IL-6, IL-18, and IL-37, and other biomarkers in the pathogenesis and management of AOSD. Owing to the rarity of the disease, there are very limited clinical trials evaluating management strategies for AOSD. The current AOSD treatment paradigm includes non-steroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids initially, conventional synthetic disease-modifying anti-rheumatic drugs in steroid-refractory patients, and biologics in those resistant to conventional treatment. Only a few country-specific guidelines for the management of AOSD have been published, and a treat-to-target approach, as previously recommended for SJIA, is still lacking. Canakinumab is the only FDA-approved biologic for the treatment of AOSD.

CONCLUSION

Emerging evidence supports that AOSD and SJIA represent a continuum of the same disease entity. Despite advancements in the understanding of AOSD, it continues to pose a substantial burden on patients and the healthcare systems, and substantial unmet needs exist across key domains such as the pathway to diagnosis, use of biomarkers in clinical practice, and standardized treatment strategies. Further research and collaboration is crucial for optimizing the diagnosis and management of AOSD patients.

Characteristics and Clinical Value of 18F-FDG PET/CT in the Management of Adult-Onset Still's Disease: 35 Cases

While the diagnosis of adult-onset Still’s disease (AOSD) involves the exclusion of differential diagnoses, the characteristics and value of 18F-Fluorodeoxyglucose (18F-FDG) Positron Emission Tomography coupled with CT (PET/CT) in the management of AOSD remain poorly known. Our retrospective study included patients from four centers, fulfilling Yamaguchi or Fautrel criteria, who underwent a PET/CT during an active AOSD. Thirty-five patients were included. At the time of PET/CT, the Yamaguchi criteria were met in 23 of 29 evaluable cases. PET/CT showed bone marrow (74.3%), lymph node (74.3%), and splenic (48.6%) FDG uptake. Despite arthralgia or arthritis in most patients, joints were rarely the sites of 18F-FDG accumulation. The spatial distribution of 18F-FDG uptake was nonspecific, and its intensity could be similar to malignant disease. Lymph node or bone marrow biopsy was performed after PET/CT in 20 patients (57.1%). The intensity of bone marrow; splenic and lymph node hypermetabolism appeared to be correlated with disease activity. Abnormal PET/CT in the cervical lymph nodes and age ≥ 60 years seemed to be predictive factors for monocyclic evolution. The clinical value of PET/CT is not in direct diagnosis; but as an aid in excluding differential diagnoses by searching for their scintigraphic features and guiding biopsy.

Acute severe hepatitis in adult-onset Still's disease: case report and comprehensive review of a life-threatening manifestation

Acute severe hepatitis is a rare complication of adult-onset Still's disease (AOSD). This condition is poorly characterized. We performed a review of the medical literature to describe clinical, biological, pathological, and treatment characteristics from AOSD patients with acute severe hepatitis. Their characteristics were compared with AOSD patients without severe hepatitis. Twenty-one cases were collected including a new case reported here. Patients with severe hepatitis were mostly young adults with a median age of 28 years (range: 20 to 55 years). Overall, patients with severe hepatitis had less arthritis, macular rash, sore throat, lymphadenopathy, or splenomegaly than patients without severe hepatitis. Cytopenia was more frequent in case of severe hepatitis. Most patients were treated with steroids, and the use of biotherapies has increased over the last decade. Despite treatment, 49% of patients required liver transplantation and 24% died. Key Points • Acute severe hepatitis in adult-onset Still's disease (AOSD) is associated with liver transplantation and/or death in, respectively, 43% and 24% of cases. • Severe hepatitis is the inaugural manifestation of AOSD in half of cases. Diagnosis is difficult when extra-hepatic clinical manifestations are lacking. • The mechanism of hepatic necrosis in AOSD with severe hepatitis is unknown. Liver biopsy is not specific and should not delay treatment initiation.

Enfermedad de Still del adulto: características clínicas y pronóstico de una cohorte de pacientes colombianos

Introducción. La enfermedad de Still del adulto (ESA) es una condición médica poco frecuente que puede presentar complicaciones graves; sin embargo, aún no se conocen con claridad sus factores de riesgo, sus factores pronósticos, ni los aspectos asociados a las recaídas y a la refractariedad a esteroides en individuos con esta condición.Objetivos. Describir el comportamiento clínico de la ESA y determinar los factores asociados a la refractariedad a esteroides, a recaídas y a complicaciones en pacientes con esta enfermedad.Materiales y métodos. Estudio retrospectivo de cohortes que incluyó 45 pacientes diagnosticados con ESA entre enero de 2007 y enero de 2017 en 2 hospitales de referencia. Se presentan medidas de resumen. Se realizaron dos análisis de regresión logística, uno crudo y otro multivariado, para identificar posibles factores que expliquen la refractariedad a esteroides, las recaídas y el desarrollo de complicaciones en la población de estudio.Resultados. La edad promedio de los participantes fue 42.13±15.8 años. De los 45 pacientes incluidos, 23 (51.1%) eran mujeres, a 42 (93.3%) se le prescribieron esteroides, y, de estos, 13 (32%) se consideraron refractarios a esteroides. Se presentaron complicaciones en 12 (26.7%) individuos y su frecuencia fue mayor en pacientes con temperatura máxima >39°C. Finalmente, 33 (73.3%) pacientes tuvieron un seguimiento mayor a 1 año, de los cuales, 17 (37.8%) presentaron recaídas, las cuales fueron más frecuentes en individuos refractarios a esteroides o con esplenomegalia. Conclusión. Los pacientes que recibieron cualquier tipo de terapia biológica fueron más refractarios a esteroides; por su parte, la refractariedad a esteroides y la esplenomegalia se asociaron a un mayor número de recaídas, y la temperatura >39°C se asoció a al desarrollo de complicaciones.

Elderly-onset Still's Disease Complicated by Macrophage Activation Syndrome: A Case Report and Review of the Literature

Adult-onset Still's disease (AOSD) usually affects young adults. Some cases of elderly-onset Still's disease (EOSD) have been reported, but its clinical features are unclear. We herein report a 74-year-old woman who developed AOSD with macrophage activation syndrome (MAS). We also reviewed 24 previous EOSD cases in patients over 70 years old and compared the findings with overall AOSD. While the clinical features were similar between the two, including the presence of MAS, disseminated intravascular coagulation was more frequent in EOSD than in AOSD. Furthermore, despite a similar frequency of glucocorticoid use, immunosuppressants and biologics were less frequently administered in EOSD than in AOSD. This report highlights the fact that typical AOSD can develop in elderly patients with some characteristic features.

Racial/Ethnic variations in morbidity and mortality in Adult Onset Still's Disease: An analysis of national dataset

OBJECTIVES

Adult Onset Still's Disease (AOSD) is a rare autoinflammatory disorder. There is relatively little known about the impact of social determinants of health on its outcomes. Our goal is to describe the racial/ethnic variations, morbidity and mortality of AOSD hospitalized patients in the US.

MATERIALS AND METHODS

Adult US hospitalized patients between 2009-13 from a nationwide inpatient sample (NIS) database with AOSD were identified using ICD-9 code 714.2. NIS is the largest all-payer US inpatient database with approximately 8 million hospitalizations yearly. Patients with other autoimmune diseases were excluded. We used descriptive statistics to summarize patient and hospital characteristics. We performed survey-weighted logistic regression models adjusting for confounders to study our primary outcome: in-hospital mortality.

RESULTS

Between 2009-13, 5,820 AOSD patients were hospitalized with a mean age of 53.6 (SE-0.61) years. 3817 (65.6%) were female, 56% white and 3% Asian. Macrophage Activating Syndrome (1.7%), Disseminated Intravascular Coagulation (DIC-1.1%) and Thrombotic Thrombocytopenic Purpura (0.4%), respectively, complicated the hospital course. There were 154 inpatient deaths in study period (mortality 2.6%). Mean age of patients who died in hospital was higher (62.4 years ± 3.1) and 13.9% were Asians. Patients of Asian origin had significantly higher odds of in-hospital death compared to whites (aOR = 6.39, 95% CI 1.77-23.1, p = 0.005). Mortality was significantly higher for patients whose hospital course was complicated by DIC (aOR = 29.69, 95% CI 5.5-160.41, p = 0.006).

CONCLUSIONS

In this national sample of patients hospitalized for AOSD, we found significant variations in In-hospital mortality.

Clinical analysis of 215 consecutive cases with fever of unknown origin: A cohort study

Fever of unknown origin (FUO) is a frequently observed phenomenon in clinical practice. The present study was aimed to investigate potential causes of FUO, thereby improving clinical diagnosis of this disorder.In this retrospective study, clinical data were collected from 215 patients who were diagnosed with FUO between January 2009 and December 2010, and an 18 to 36 months follow-up visit was also performed for these patients.Among these FUO cases, the most common causes of the disease were infectious diseases (IDs) (42.3%), followed by connective tissue diseases (CTDs) (32.1%), miscellaneous (Mi) (10.7%) and neoplasm (N) (6.5%), while the causes for the other 18 cases (8.4%) were still unknown. The most common types of ID, CTD, and N were tuberculosis (16/91, 17.6%), adult onset Still disease (AOSD) (37/69, 53.6%) and non-Hodgkin lymphoma (6/14, 42.9%), respectively.IDs still represent the most common causes of FUO. Regularly intermittent fever with urinary infections and irregularly intermittent fever with infective endocarditis may be regarded as some signs in clinical diagnosis of FUO.

Myocarditis in adult-onset still disease

This study highlights the clinical features, treatments, and outcomes of the rare myocarditis in adult-onset Still disease (AOSD). Among a case series of 57 patients fulfilling either Yamaguchi or Fautrel AOSD criteria and seen between 1998 and 2010, we identified 4 cases of myocarditis. From a comprehensive literature review, we collected 20 additional cases of myocarditis-complicated AOSD. The characteristics of patients with myocarditis were compared with those of AOSD patients without myocarditis.In these 24 myocarditis-complicated AOSD cases, myocarditis occurred early and was present at AOSD onset in 54% of the cases. Myocarditis was often symptomatic (96% of patients) with nonspecific electrocardiographic abnormalities (79% of patients) and a left ventricle ejection fraction ≤50% (67% of patients). Cardiac magnetic resonance imaging and endomyocardial biopsies showed features consistent with myocarditis in 4 patients and a mononuclear interstitial inflammatory infiltrate in 4 others. Steroids alone were effective in 50% of patients with myocarditis. Intravenous immunoglobulins, methotrexate, and tumor necrosis factor-α-blockers were also prescribed and often found effective. Only 1 patient died from cardiogenic shock. Patients with myocarditis-complicated AOSD were younger and more frequently male than patients with AOSD alone. Pericarditis was more frequent in the myocarditis group; white blood cell count, polymorphonuclear cell count, and serum ferritin levels were also higher.Myocarditis is a potentially life-threatening complication of AOSD but responds positively to steroids and other immunomodulatory drugs. Its prognosis remains good (only 1 death occurred), but the condition requires close monitoring of heart function.

Cutaneous manifestations of adult-onset Still's disease: a case report and review of literature

Adult onset Still's disease (AOSD) is a systemic inflammatory disorder of unknown etiology and pathogenesis characterized by high spiking fever, arthralgia or arthritis, sore throat, lymphadenopathy, hepatosplenomegaly, serositis, and transient cutaneous manifestations. Although more common in children, cases are seen also in adults. Cutaneous involvement is common and may be suggestive for the diagnosis. A case of AOSD in a 35-year-old man is reported here, presenting with urticarial maculopapular rash of trunk, high spiking fever, acute respiratory distress syndrome, and myopericarditis. Skin biopsy showed interstitial and perivascular mature CD15(+) neutrophils. A comprehensive review of literature showed that cutaneous involvement occurs in about 80 % of patients, with various clinical presentations. The most common skin manifestation is an evanescent salmon pink or erythematous maculopapular exanthema, predominantly on the trunk and proximal limbs, with rare involvement of face and distal limbs. Less common manifestations include persistent erythematous plaques and pustular lesions. A constant histopathologic finding is the presence of interstitial dermal neutrophils aligned between the collagen bundles. This pattern may provide an easy accessible clue for the definitive diagnosis of AOSD and exclude other diagnosis such as drug eruptions or infectious diseases.

Adult-onset Still's disease

First described in 1971, adult-onset Still's disease (AOSD) is a rare multisystemic disorder considered as a complex (multigenic) autoinflammatory syndrome. A genetic background would confer susceptibility to the development of autoinflammatory reactions to environmental triggers. Macrophage and neutrophil activation is a hallmark of AOSD which can lead to a reactive hemophagocytic lymphohistiocytosis. As in the latter disease, the cytotoxic function of natural killer cells is decreased in patients with active AOSD. IL-18 and IL-1β, two proinflammatory cytokines processed through the inflammasome machinery, are key factors in the pathogenesis of AOSD; they cause IL-6 and Th1 cytokine secretion as well as NK cell dysregulation leading to macrophage activation. The clinico-biological picture of AOSD usually includes high spiking fever with joint symptoms, evanescent skin rash, sore throat, striking neutrophilic leukocytosis, hyperferritinemia with collapsed glycosylated ferritin (<20%), and abnormal liver function tests. According to the clinical presentation of the disease at diagnosis, two AOSD phenotypes may be distinguished: i) a highly symptomatic, systemic and feverish one, which would evolve into a systemic (mono- or polycyclic) pattern; ii) a more indolent one with arthritis in the foreground and poor systemic symptomatology, which would evolve into a chronic articular pattern. Steroid- and methotrexate-refractory AOSD cases benefit now from recent insights into autoinflammatory disorders: anakinra seems to be an efficient, well tolerated, steroid-sparing treatment in systemic patterns; tocilizumab seems efficient in AOSD with active arthritis and systemic symptoms while TNFα-blockers could be interesting in chronic polyarticular refractory AOSD.

Adult-onset still disease: manifestations, treatment, outcome, and prognostic factors in 57 patients

We conducted a retrospective observational study to describe a cohort and identify the prognostic factors in adult-onset Still disease (AOSD). Patients enrolled in this retrospective chart review fulfilled either Yamaguchi or Fautrel criteria. Candidate variables were analyzed with logistic unadjusted and adjusted regression models. Fifty-seven patients were seen in the internal medicine (75%) and rheumatology (25%) departments over a mean period of 8.4 years. The median time to diagnosis was 4 months. The course of AOSD was monocyclic in 17 patients, polycyclic in 25, and chronic in 15. The assessment of glycosylated ferritin (GF) in 37 patients was correlated with early diagnosis. Nine F-fluorodeoxyglucose positron emission tomography (FDG-PET) scans identified the lymph nodes and glands as the main sites of hypermetabolism. Complications were frequent (n = 19), including reactive hemophagocytic syndrome (n = 8). None of the 3 deaths could be attributed to AOSD. Corticosteroid dependence, as predicted by a low GF level, occurred in 23 patients (45%). A quarter of the patients received tumor necrosis factor-α blockers or anakinra with good tolerance. Fever >39.5 °C was predictive of monocyclic AOSD, while arthritis and thrombocytopenia were associated with chronic and complicated AOSD, respectively. The youngest patients had the highest risks of resistance to first-line treatments.AOSD remains difficult to diagnose. Mortality is low despite frequent complications. GF and FDG-PET scans were of value in the diagnostic approach. The condition in highly symptomatic patients evolved to systemic AOSD, whereas more progressive patterns with arthritis predicted chronic AOSD.

[Cardio-respiratory involvement in adult-onset Still's disease]

Cardiopulmonary involvement in adult-onset Still's disease is not as common as cutaneous and articular involvement. Pleuropericarditis is the most frequent thoracic manifestation. Although difficult, diagnosis of other thoracic manifestations, which may reveal the disease, is crucial, due to the high risk to life and the efficacy of new immunosuppressive agents. The pathophysiology involves essentially immunological factors, Still's disease being increasingly seen as an autoimmune inflammatory disease. Pro-inflammatory cytokines such as interleukine (IL) 1, 6 and 18 play a crucial role in macrophage activation, which is central in the pathophysiology of adult Still's disease. The classification of cardiopulmonary manifestations is based on anatomy. Cardiac lesions may involve all the tissues of the heart and the pulmonary arteries. Respiratory lesions may involve the pleura, the lung parenchyma (organizing pneumonitis, infiltrative lung disease, alveolar damage, amyloidosis), and the respiratory muscles, including the diaphragm. Finally, some manifestations may be provoked by the treatment itself. Steroids, the first-line treatment, are very effective in pleuropericarditis. Methotrexate used to be prescribed when steroids failed, but biotherapies such as IL1 and IL6 inhibitors have transformed the prognosis of forms resistant to these drugs.

Metabolomic study of the fever model induced by baker's yeast and the antipyretic effects of aspirin in rats using nuclear magnetic resonance and gas chromatography-mass spectrometry

A metabolomic investigation of baker's yeast-induced fever in rats was carried out. Plasma derived from Sprague-Dawley rats treated by subcutaneous administration of 20% (w/v) baker's yeast was analyzed using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR). Statistical data analysis using t-test and orthogonal partial least-squares discriminant analysis revealed many significant changes in the metabolic data in the plasma of the fever group. Clear separation was achieved between the fever and control groups. Seventeen marked metabolites were found in the fever group. The metabolites, which include amino acids, carbohydrate, organic acids, and fatty acids, mostly contributed to the discrimination of plasma samples from the control and fever groups. These results suggested that fever may involve in the perturbation of amino acid metabolism coupled with energy metabolism, lipid metabolism, and glycometabolism. After determining the antipyretic effects of aspirin on the fever group, four metabolites in the fever rat plasma were found to be signally regulated and recognized as potential biomarkers, including 3-hydroxybutyric acid, gamma-aminobutyric acid, glucose, and linoleic acid. The metabolic relationships that possibly exist between these potential biomarkers were speculated, and the mechanism of baker's yeast-induced fever was illustrated based on the metabolic relationships. This study found that metabolomic approaches such as GC-MS and NMR could be used as potential powerful tools to investigate the biochemical changes and mechanisms in certain pathological states at the metabolism level.