RS3PE: Clinical and Research Development

Development of Remitting Seronegative Symmetrical Synovitis with Pitting Edema Syndrome with Pembrolizumab for Lung Squamous Cell Carcinoma

Immune checkpoint inhibitors (ICIs) can cause immune-related adverse events (irAEs). There are a few case reports of remitting seronegative symmetrical synovitis with pitting edema syndrome (RS3PE) as an irAE. We herein report a 49-year-old Japanese man who developed acute-onset polyarthralgia and edema of the back of both hands and bilateral lower legs after pembrolizumab administration for lung cancer. The patient's lung cancer was in complete remission, leading to the diagnosis of RS3PE induced by pembrolizumab rather than malignancy. When patients show RS3PE during ICI treatment, rheumatologists should consider the possibility of an irAE after excluding malignancy and systemic diseases.

Remitting Seronegative Symmetrical Synovitis With Pitting Oedema Associated With Malignancy: A Case Report

Remitting seronegative symmetrical synovitis with pitting oedema is a rare rheumatological condition, predominating in the elderly male. It is characterised by the abrupt onset of marked pitting oedema, symmetrical distal synovitis, absence of rheumatoid factor and an excellent response to glucocorticoids. RS3PE may be the harbinger of a malignancy so the diagnosis should prompt evaluation and exclusion of such condition; in these cases, the response to glucocorticoids is only partial and treating the neoplasia is essential. The differential diagnosis includes late-onset rheumatoid arthritis, polymyalgia rheumatica and calcium pyrophosphate crystal-related arthritis. We present the case of a patient with remitting seronegative symmetrical synovitis with pitting oedema associated with clear cell renal cell carcinoma.

Anti-interleukin-6 receptor antibody for the treatment of remitting seronegative symmetrical synovitis with pitting oedema: a new outlook?

We present the case of an elderly man with a small-joint polyarthritis, accompanied by pitting oedema, involving hands and feet, raising clinical suspicion of remitting seronegative symmetrical synovitis with pitting oedema (RS3PE). Treatment with corticosteroids was initiated with significant improvement, but unacceptable iatrogeny ensued, and tapering was not possible without disease flare-up. A trial of tocilizumab allowed disease activity control, slow weaning of corticosteroids and, ultimately, its suspension. RS3PE is a rare rheumatological entity, initially thought to be a variant of rheumatoid arthritis (RA), with shared traits with polymyalgia rheumatica (PMR), and other seronegative spondyloarthropathies, thereby implying a shared pathophysiological background. Elevated levels of interleukin 6 (IL-6) are found in patients with RA, have shown to mirror disease activity in PMR and have also been described in the serum and synovial fluid of patients with RS3PE. Tocilizumab, an anti-IL-6 receptor antibody, shows auspicious results in several other rare rheumatic diseases other than RA.

Case Report: Resolution of remitting seronegative symmetrical synovitis with pitting edema during nivolumab therapy for gastric cancer

The anti-programmed cell death-1 (PD-1) antibody nivolumab has been shown to significantly prolong the survival of patients with unresectable advanced or recurrent gastric cancer (AGC). However, immune-related adverse events (irAEs), which show different profiles from those of cytotoxic agents or conventional molecular-targeted drugs including tyrosine kinase inhibitors, have been reported. Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare autoimmune disorder with acute-onset, rheumatoid factor-negative, symmetric synovitis associated with limb edema observed in elderly persons. A case of RS3PE syndrome that developed after administration of nivolumab for advanced gastric cancer is reported. This is the first report of a case of RS3PE syndrome as an irAE caused by nivolumab in a patient with gastric cancer.

Update on Imaging of Inflammatory Arthritis and Related Disorders

Arthritis and other rheumatic disorders are very frequent in the general population and responsible for a huge physical and disability burden to affected patients as well as a major cost to the society. Precise evaluation often relies on clinical data only but additional imaging may be required i) for a more objective assessment of the disease status, such as in rheumatoid arthritis (RA) or ankylosing spondyloarthritis (AS), ii) for providing prognostic information and evaluating response to treatment or iii) for establishing diagnosis, in patients with unclear clinical picture, such as polymyalgia rheumatica (PMR) and large-vessel vasculitis (LVV). Besides radiological techniques (x-rays, ultrasound, and MRI), functional and molecular imaging has emerged as a valid tool for this purpose in several disorders. Bone scanning has long been a method of choice but is now more used as a triage tool in patients with unclear complaints, including degenerative disorders (eg osteoarthritis). ¹⁸F-FDG-PET/CT (FDG) proved efficient in assessing the extent of the disease and response to treatment in RA and related disorders, and to provide accurate diagnosis in some systemic disorders, including PMR and LVV. Based on glucose metabolism, FDG-PET/CT is able to show increased metabolism in peripheral cells involved in inflammation (eg neutrophils, lymphocytes or monocytes/macrophages) but also in fibroblasts that proliferate in the pannus. The lack of specificity of FDG is a limitation and many alternative tracers were developed at the preclinical stage or applied in the clinics, especially within clinical trials. They include imaging of macrophages using translocator protein (TSPO), folate-receptors or other targets on activated cells. These new tools will undoubtedly become more and more available in the everyday clinical workup of patients with rheumatisms. Finally, it should be kept in mind that a very simple tracer, ¹⁸F-fluoride is widely more performant in AS than FDG.

Remitting Seronegative Symmetrical Synovitis with Pitting Edema Syndrome as a Manifestation of Recurrent Ovarian Cancer

We herein report a case of ovarian cancer recurrence detected every time with symptoms of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome. A 46-year-old woman who had a history of ovarian cancer 9 months earlier developed joint pain along with pitting edema in both hands and was diagnosed with RS3PE syndrome. Two and four years after initial surgery for ovarian cancer, symptoms of RS3PE syndrome appeared, and a recurrent site was detected. With resection of the relapsed sites and increased maintenance dose of methylprednisolone, these symptoms improved within a month.

[Paraneoplastic syndromes in rheumatology]

Paraneoplastic syndromes in rheumatology are a group of canonical rare rheumatic diseases with musculoskeletal involvement that occur in close temporal and causal association with malignancies. Knowledge of these possibly enables a prognostically relevant early diagnosis of the underlying malignant disease. In the era of immune checkpoint inhibitor treatment, there are first indications of an increase in the incidence and severity of paraneoplastic syndromes, so that they are becoming of increasing importance for the practicing rheumatologist. These nine syndromes, paraneoplastic arthritis, palmar fasciitis and polyarthritis, remitting seronegative symmetrical synovitis with pitting edema, pancreatic panniculitis with polyarthritis, paraneoplastic vasculitis, cancer-associated myositis, hypertrophic osteoarthropathy (Marie-Bamberger), eosinophilic fasciitis and tumor-induced osteomalacia, usually occur with characteristic courses and sometimes pathognomonic clinical manifestations, which are presented in this article accompanied by the rational use of a diagnostic algorithm for tumor detection. With frequently disappointing therapeutic response to glucocorticoids, nonsteroidal antirheumatic drugs and immunosuppressants, treatment of the underlying malignant disease represents the crucial step in the treatment of paraneoplastic syndromes.

Differentiating between Seronegative Elderly-Onset Rheumatoid Arthritis and Polymyalgia Rheumatica: A Qualitative Synthesis of Narrative Reviews

Elderly-onset rheumatoid arthritis (EORA) is prevalent among older patients, and its incidence is increasing due to aging societies. However, differentiating between EORA and polymyalgia rheumatica (PMR) is challenging for clinicians and hinders the initiation of effective treatment for rheumatoid arthritis among older generations, thereby allowing its progression. Therefore, we conducted a qualitative synthesis of narrative reviews via meta-ethnography regarding seronegative EORA diagnosis to clarify the methods to differentiate seronegative EORA from PMR. Three databases (PubMed, EMBASE, and Web of Science) were searched for relevant reviews published between January 2011 and October 2022. The extracted articles were synthesized using meta-ethnography, and 185 studies were selected following the protocol. Seven reviews were analyzed, and four themes and nine concepts were identified. The four themes included difficulty in differentiation, mandatory follow-up, and factors favoring rheumatoid arthritis and those favoring PMR. Factors favoring seronegative EORA and PMR should be considered for effective diagnosis and prompt initiation of disease-modifying anti-rheumatic drugs. Mandatory and long follow-ups of suspected patients are essential for differentiating the two diseases. The attitude of rheumatologists toward tentatively diagnosing seronegative EORA and flexibly modifying their hypotheses based on new or altered symptoms can aid in effective management and avoiding misdiagnosis.

Polyarthritis presented in a patient with untreated chronic hepatitis B infection

Hepatitis B virus (HBV) infection can cause arthritis, but it is rarely reported. In the current report, we present a case of chronic polyarthritis in a patient with untreated HBV infection. A 63-year-old woman suffering from polyarthritis in her fingers visited our institution. She had experienced exacerbations and remissions of polyarthritis for more than 20 years. She had been diagnosed with rheumatoid arthritis and had been treated with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and nonsteroidal anti-inflammatory drugs by her primary care doctor, but the csDMARDs were discontinued at the request of the patient 10 years before the first visit to our hospital. The blood test showed negative for rheumatoid factor and anticyclic citrullinated peptides antibody but positive for hepatitis B surface antigen. Hepatitis B surface antigen and HBV-Deoxyribo Nucleic Acid (DNA) were increased to 312.6 (IU/ml) and 4.6 (log copies/ml), respectively. Based on the results of abdominal computed tomography and echography, she was diagnosed with liver cirrhosis. Treatment for HBV infection was begun with oral tenofovir at 25 mg/day. The polyarthritis in her fingers gradually disappeared and has not relapsed for 6 months after the initiation of treatment for HBV infection. When polyarthritis is diagnosed, the possibility that chronic HBV infection can be one of the causes of polyarthritis should be considered.

Case Report: Syndrome of Remitting Seronegative Symmetrical Synovitis with Pitting Edema-A Rare but Treatable Condition in Palliative Medicine

The syndrome of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare diagnosis that is often missed due to lack of both definitive diagnostic criteria and awareness of the disease. This case report describes a patient with chronic lymphocytic leukemia whose diagnosis of RS3PE was possibly delayed due to concomitant treatment-related arthralgias. The pathophysiology, presentation, and treatment of RS3PE are discussed. Greater awareness of malignancy-related RS3PE is crucial from a palliative care perspective as typical opioid pain management will prove ineffective and delay appropriate treatment.

Harnessing hyaluronic acid for the treatment of osteoarthritis: A bibliometric analysis

Background: Osteoarthritis (OA) is a common disease which usually occurs in middle-aged and elderly people. Hyaluronic acid (HA) has been widely used to treat OA and related researches on the efficacy and safety of HA in the treatment of OA have been published. Therefore, the purpose of this research was to investigate the subject characteristics of harnessing HA for the treatment of OA and to analyse the relevant trends and hotspots by using a bibliometric approach.

Methods: The articles published from 1 January 2002 to 31 December 2021 were searched in the Web of Science Core Collection (WoSCC) and the relevant information of HA for the treatment of OA was extracted after screening. Then, a total of 2438 publications were analysed by using Microsoft Excel, CiteSpace 5.8.R3, VOSviewer 1.6.18 and the Online Analysis Platform of Literature Metrology (http://bibliometric.com/).

Results: A total of 2438 articles were finally included for analysis. The number of publications increased year by year. A total of 83 coutries and 3319 institutions published 2438 manuscripts in the field of use HA for the treatment of OA. The most productive country was United States with total 689 publications and League of European Research Universities Leru (Belgium) was the leading institution with total 126 publicatios. In terms of authors, the most prominent author was KrausVB, who published 28 papers with the highest H-index (19). In addition, Osteoarthritis and Cartilage had the highest number of publications (152 articles) and the highest number of citations (6450 citations). The co-cited references analysis indicated that the article published by McAlindon in 2014 had the most highest number of citations (91co-citations). What’s more, most research hotspots focused on the efficacy and safety of HA, and regenerative medicine researches such as platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) have attracted more and more attentions of researchers.

Conclusion: This study visually analyzed the historical evolution and future trends of HA for the treatment of OA, and discussed the research priorities. At present, there are still different views on the efficacy of HA for the treatment of OA. Gradually, research hotspots of this field have focused on the regenerative medicine.

Idiopathic remitting seronegative symmetrical synovitis with pitting edema syndrome mimicking symptoms of polymyalgia rheumatica: a case report

Background

Remitting seronegative symmetrical synovitis with pitting edema is a rare rheumatic condition of the elderly population that is well described but whose mechanisms remain little studied. This syndrome is characterized by symmetrical swelling located mainly on the dorsal part of the hands and the feet. Because of possible heterogeneous clinical presentation, it can easily mimic the onset of other rheumatic diseases or appear associated with them. Here we report a case of a patient who developed remitting seronegative symmetrical synovitis with pitting edema with preexisting shoulder and hip girdle pain associated with progressive fatigue, indicating a possible differential diagnosis of polymyalgia rheumatica. We reviewed and compared classification for remitting seronegative symmetrical synovitis with pitting edema and polymyalgia rheumatica and discussed other differential diagnoses.

Case presentation

An 84-year-old Caucasian woman presented to our General Medicine Unit with acute onset of symmetrical hands and feet edema, leading to functional limitation due to pain and stiffness. Additionally, she was complaining about neck, shoulder, and pelvic girdle pain present for about 2 months associated with worsening asthenia. Blood tests showed an elevated level of C-reactive protein and erythrocyte sedimentation rate, as well as absence of anti-cyclic citrullinated peptide antibodies and rheumatoid factor. As all criteria of remitting seronegative symmetrical synovitis with pitting edema syndrome were present, the patient was treated with low-dose prednisone, with a rapid and complete resolution of symptoms. She remains asymptomatic without treatment 2 years after the onset of symptoms, without any evident oncologic etiology.

Conclusions

This case is an example of a classic representation of remitting seronegative symmetrical synovitis with pitting edema syndrome with clinical elements suggesting a concomitant existing early stage of polymyalgia rheumatica. These two entities, classified in the group of seronegative arthritis, can coexist (up to 10% of cases), with remitting seronegative symmetrical synovitis with pitting edema appearing as an initial or late manifestation of polymyalgia rheumatica. It is essential to remind that remitting seronegative symmetrical synovitis with pitting edema is associated with a higher risk of cancer (30%). A proper diagnosis allows the clinician to precisely define the appropriate therapy duration to limit its side effects in the elderly and remain aware of the potential risk of underlying malignancy.

RSЗPE Syndrome: Autoinflammatory Features of a Rare Disorder

Remitting seronegative symmetrical synovitis with pitting edema (RSЗPE) syndrome was first described by McCarty in 1985 and is characterized by pitting edema and an acute symmetrical synovitis of small joints. Self-directed inflammation in autoimmune disorders is caused by an abnormal activation of the adaptive immune system, while in autoinflammatory disorders is due to aberrant activation of the innate immune system without autoantibodies or autoreactive T cells. The role of autoimmunity in the pathogenesis of RSЗPE syndrome is suggested by possible associations with some autoimmune diseases and HLA haplotypes. However, several other features point to a possible role of autoinflammation in RSЗPE syndrome. In this review, the relative contributions of both innate and adaptive immune systems to the pathogenesis of RSЗPE syndrome are discussed.

Remitting seronegative symmetrical synovitis with pitting edema: a case report

Background

Edema occurs in various disorders. One of those is remitting seronegative symmetrical synovitis with pitting edema, a rare syndrome whose pathophysiology is not clearly understood. We report herein a case of refractory edema diagnosed as remitting seronegative symmetrical synovitis with pitting edema.

Case presentation

A 82-year-old Asian male was admitted to the Department of General Internal Medicine with a 2-month history of symmetrical swelling of both hands. Despite treatment with loop diuretic furosemide 40 mg daily, his condition did not respond to the medication and his quality of life deteriorated. An examination of the joints showed tenderness suggestive of synovitis with restricted movements in bilateral proximal interphalangeal joint. Laboratory findings revealed hyperglycemia, elevated erythrocyte sedimentation rate 118 mm/hour, and elevated C-reactive protein 6.58 mg/dL. Plain radiographs of both hands showed soft tissue swelling, changes consistent with osteoarthritis, and no erosions. The diagnosis of bilateral remitting seronegative symmetrical synovitis with pitting edema was made. Treatment with prednisolone 15 mg daily was instituted.

Conclusions

Although remitting seronegative symmetrical synovitis with pitting edema is rare, it should be remembered as a disease that causes edema in the elderly.

Paraneoplastic Arthritides: Insights to Pathogenesis, Diagnostic Approach, and Treatment

ABSTRACT

Paraneoplastic arthritides are a group of inflammatory rheumatic syndromes induced by an occult and manifest malignancy, characterized by a wide range of musculoskeletal signs and symptoms that masquerade other rheumatic diseases such as rheumatoid arthritis. Although the pathogenesis of paraneoplastic arthritides is unknown, immune-mediated mechanisms can induce a paraneoplastic syndrome, with a dominant feature the polyarthritis. Common entities of paraneoplastic arthritides include paraneoplastic polyarthritis, hypertrophic osteoarthropathy, remitting seronegative symmetrical synovitis with pitting edema, palmar fasciitis and polyarthritis, and polyarthritis and panniculitis associated with pancreatic carcinoma. The electronic databases PubMed and Scopus were scrutinized using the following terms: paraneoplastic arthritis, paraneoplastic polyarthritis, or paraneoplastic rheumatic diseases. Abstracts, full articles, and selected references were reviewed. The aim of the present narrative review article was to describe the clinical characteristics, diagnostic evaluation, and management of paraneoplastic arthritides, and highlight the challenges that health care providers may encounter, distinguishing those conditions from other autoimmune rheumatic disorders. Future studies are needed to give insight into the mechanisms associated with paraneoplastic arthritides, leading to the development of novel diagnostic biomarkers.

A Case of Localized Prostate Cancer Associated with Polymyalgia Rheumatica with Marked Symptomatic Improvement after Robot-Assisted Radical Prostatectomy

A 73-year-old man visited our hospital with chief complaints of fever of unknown origin and bilateral shoulder and hip joint pain. He was initially diagnosed with polymyalgia rheumatica (PMR). Although the patient was treated with prednisolone 15 mg/day, his PMR-related symptoms did not improve. Further examination was performed as the patient was suspected of having paraneoplastic syndrome. Assessment results showed prostate cancer without metastases. After undergoing robot-assisted radical prostatectomy, the patient's PMR-related symptoms dramatically improved. Hence, the prednisolone dose was decreased to 4 mg/day. PCa may have triggered the development of PMR through the activation of immune-mediated systemic inflammatory responses.

bFGF could be a biomarker of malignancy in RS3PE syndrome: an ambispective single-center cohort analysis of 51 patients

Objectives

Remitting seronegative symmetrical synovitis with pitting edema (RS₃PE) is a rare inflammatory arthritis, with a higher incidence of malignancy. The aim of this study is to identify biomarkers for predicting malignancy in RS₃PE.

Methods

A total of 51 patients with RS₃PE from September 2007 to May 2019 were retrospectively reviewed and followed for up to 5 years, with 15 patients with osteoarthritis (OA) and 14 patients with elderly-onset rheumatoid arthritis (EORA) as disease controls. Serum levels of angiogenesis cytokines were measured by electrochemiluminescent immunoassay and Luminex Human Magnetic Assay. Clinical data and laboratory parameters were analyzed to identify risk factors for malignancy.

Results

A total of forty-eight RS₃PE patients (94.1%) were available with follow-up data; 8 patients (16.7%) were diagnosed with malignancy, of which 6 patients were hematological tumor; and 2 patients were solid tumors. Serum levels of basic fibroblast growth factor (bFGF) were exclusively higher in RS₃PE patients with malignancy [14.21 (7.52, 23.18) ng/mL] than RS₃PE patients without malignancy [4.32 (2.88, 7.42) ng/mL], OA [3.20 (2.20, 5.30) ng/mL], and EORA [3.20 (2.20, 5.30) ng/mL]. The optimal cut-off value of bFGF for malignancy was 10ng/mL in RS₃PE. Logistic regression analysis indicated that elevation of bFGF was a risk factor for malignancy in RS₃PE.

Conclusions

This study indicated that bFGF was elevated in RS₃PE patients with malignancy and could serve as a biomarker for predicting paraneoplastic RS₃PE.

Remitting seronegative symmetrical synovitis with pitting oedema following BNT162b2 mRNA COVID-19 vaccination

Remitting seronegative symmetrical synovitis with pitting oedema (RS3PE) is a rare inflammatory condition that occurs in older adults. Here, we report a case of an 80-year-old man with no history of rheumatic disease who presented with acute onset of bilateral hand pain, pitting oedema and synovitis after the second dose of the BNT162b2 mRNA C0VID-19 vaccine. Laboratory workup revealed elevated inflammatory markers and negative autoantibodies. Significant improvement was noted with prednisolone. This is the first reported case of RS3PE in an elderly patient with no previous rheumatic disease following mRNA COVID-19 vaccination.

The combined prevalence of classified rare rheumatic diseases is almost double that of ankylosing spondylitis

BACKGROUND

Rare diseases (RDs) affect less than 5/10,000 people in Europe and fewer than 200,000 individuals in the United States. In rheumatology, RDs are heterogeneous and lack systemic classification. Clinical courses involve a variety of diverse symptoms, and patients may be misdiagnosed and not receive appropriate treatment. The objective of this study was to identify and classify some of the most important RDs in rheumatology. We also attempted to determine their combined prevalence to more precisely define this area of rheumatology and increase awareness of RDs in healthcare systems. We conducted a comprehensive literature search and analyzed each disease for the specified criteria, such as clinical symptoms, treatment regimens, prognoses, and point prevalences. If no epidemiological data were available, we estimated the prevalence as 1/1,000,000. The total point prevalence for all RDs in rheumatology was estimated as the sum of the individually determined prevalences.

RESULTS

A total of 76 syndromes and diseases were identified, including vasculitis/vasculopathy (n = 15), arthritis/arthropathy (n = 11), autoinflammatory syndromes (n = 11), myositis (n = 9), bone disorders (n = 11), connective tissue diseases (n = 8), overgrowth syndromes (n = 3), and others (n = 8). Out of the 76 diseases, 61 (80%) are classified as chronic, with a remitting-relapsing course in 27 cases (35%) upon adequate treatment. Another 34 (45%) diseases were predominantly progressive and difficult to control. Corticosteroids are a therapeutic option in 49 (64%) syndromes. Mortality is variable and could not be determined precisely. Epidemiological studies and prevalence data were available for 33 syndromes and diseases. For an additional eight diseases, only incidence data were accessible. The summed prevalence of all RDs was 28.8/10,000.

CONCLUSIONS

RDs in rheumatology are frequently chronic, progressive, and present variable symptoms. Treatment options are often restricted to corticosteroids, presumably because of the scarcity of randomized controlled trials. The estimated combined prevalence is significant and almost double that of ankylosing spondylitis (18/10,000). Thus, healthcare systems should assign RDs similar importance as any other common disease in rheumatology.

Rheumatologische paraneoplastische Syndrome

Rheumatologische paraneoplastische Syndrome sind selten, stellten jedoch eine wichtige Differenzialdiagnose zu klassischen rheumatologischen Krankheitsbildern dar. Durch das Erkennen der eindrücklichen Syndrome mit typischen Labor- und Untersuchungsbefunden ist oftmals eine beschleunigte Diagnose der zugrundeliegenden Malignität und kurative Therapie möglich. In dieser Übersichtsarbeit werden die Charakteristika rheumatologischer paraneoplastischer Syndrome vorgestellt.

Remitting seronegative symmetric synovitis with pitting edema (RS3PE) with painful erythematous nodules

Remitting seronegative symmetric synovitis with pitting edema (RS3PE) is an uncommon syndrome characterised by acute onset severe synovitis of the radiocarpal and small joints of the hands, with associated pitting edema. Discussed here is the case of a 69-year-old man who presented to the emergency department of a tertiary hospital with acute bilateral hand swelling. This was on a background of a recent diagnosis of metastatic adenocarcinoma of the caecum and subsequent hemicolectomy. There was a history of general malaise, fever and lethargy for 5 days prior to the swelling of the hands. On examination, the upper limbs were swollen to the elbow bilaterally. Painful erythematous nodules were noted on the dorsal and palmar aspects of the hands and violaceous periungual discolouration was observed on the right fourth and fifth fingers. Prednisolone was commenced resulting in a dramatic resolution of the articular and cutaneous manifestations within 3 weeks.

Remitting seronegative symmetrical synovitis with pitting oedema after surgical remission of Cushing's syndrome

A 64-year-old woman with refractory cellulitis in the lower legs was referred for inadequate glycaemic control. Physical examination revealed cushingoid features including central obesity. CT of the abdomen revealed a right adrenal mass that was positive on ¹³¹I-adosterol imaging. Findings on endocrine evaluation confirmed a diagnosis of Cushing's syndrome, which was cured with a right adrenalectomy. Two months after surgery, the patient complained of pain and marked swelling of the hands during hydrocortisone replacement therapy (20 mg per day) given for postoperative adrenal insufficiency. Laboratory examination was unremarkable. However, contrast-enhanced T2-weighted MRI of the hands revealed enhanced signals surrounding the flexor tendons, leading to a diagnosis of remitting seronegative symmetrical synovitis with pitting oedema. Prednisolone (15 mg per day) was then initiated, and the symptoms disappeared within a few days. This case illustrates the possibility that successful treatment of Cushing's syndrome may trigger emergence of a glucocorticoid-responsive disease.

An unusual case of remitting seronegative symmetrical synovitis with pitting edema: Case report and literature review

Remitting seronegative symmetrical synovitis with pitting edema is a rare but well-recognized clinical entity that is easily overlooked due to lack of clinical vigilance. It is classically described as an acute onset of symmetrical tenosynovitis of both upper and lower extremities with pitting edema, mostly noted in elderly population. Young patients with other rheumatological diseases and unilateral involvement had also been reported, but symmetrical remitting seronegative symmetrical synovitis with pitting edema in a young patient is a rare observation. We hereby report a case of a remitting seronegative symmetrical synovitis with pitting edema in a young male affected by no rheumatological diseases in the past, typically fulfilling the diagnostic criteria and well responded to low-dose steroid therapy. The salient features of the present case in terms of age, remitting seronegative symmetrical synovitis with pitting edema possibly related to undifferentiated arthropathy, reactive arthritis, or diabetes mellitus.

Nivolumab induced remitting seronegative symmetrical synovitis with pitting edema in a patient with melanoma: a case report

BACKGROUND

Novel immune checkpoint inhibitors have been often utilized for different types of malignancies as salvage therapy with varying success. One obstacle to immune checkpoint inhibitor use is the higher incidence of immune-mediated side effects that can prompt discontinuation of therapy. Remitting seronegative symmetrical synovitis with pitting edema has been described with immune checkpoint inhibitors only once previously. We report a case of a patient who developed remitting seronegative symmetrical synovitis with pitting edema related to immune checkpoint inhibitor therapy and stress that these symptoms can be managed without cessation of immune checkpoint inhibitor therapy.

CASE PRESENTATION

We present a 70-year-old white man who presented with 4 months of progressive inflammatory arthritis with pitting edema. He had been started on nivolumab therapy for his metastatic melanoma with excellent response prior to symptom onset. The symptoms started in his knees and subsequently involved both hands and feet. On evaluation, he was wheelchair bound and completely dependent for all activities of daily living. Evaluation revealed negative serological testing and plain film imaging. Ultrasound demonstrated diffuse flexor tenosynovitis and soft tissue swelling, and a diagnosis of remitting seronegative symmetrical synovitis with pitting edema was made. He was treated with orally administered corticosteroids (0.5 mg/kg per day) which improved his symptoms significantly and allowed him to regain prior independent functioning. His corticosteroids were tapered (0.15 mg/kg per day) but not discontinued and his nivolumab treatment was not interrupted. In follow up he continued to have stable control of his melanoma as well as his remitting seronegative symmetrical synovitis with pitting edema.

CONCLUSIONS

In conclusion we present the first case of nivolumab-induced remitting seronegative symmetrical synovitis with pitting edema that is controlled by maintenance low-dose orally administered corticosteroids allowing for continuation of nivolumab therapy. Clinicians who encounter mild-to-moderate immune checkpoint inhibitor immune-mediated adverse effects can consider maintaining immune checkpoint inhibitor therapy with concomitant low-dose corticosteroids rather than abrupt cessation of the immune checkpoint inhibitor.

SAPHO Syndrome Masquerading as Metastatic Breast Cancer

SAPHO syndrome is a rare clinical entity composed of synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO). We describe a case of SAPHO syndrome masquerading as metastatic breast cancer in a patient with localized breast cancer who presented with cord compression. There was no pathologic evidence of metastatic cancer; however, a bone scan indicated osseous involvement. After multidisciplinary review of images and with additional findings of pustulosis and acne, a clinical diagnosis of SAPHO was made.

Remitting seronegative symmetrical synovitis with pitting edema syndrome complicated with primary lung cancer

Remitting seronegative symmetrical synovitis with pitting edema syndrome has been reported to be associated with malignant tumors. However, few cases occurring with lung cancer have been reported. We here report a case of remitting seronegative symmetrical synovitis with pitting edema syndrome complicated with lung cancer. A 77-year-old man presented with poly arthritis (both shoulders, knees, and hands), swelling of the hands, and an elevated C-reactive protein level. As the patient's rheumatoid factor was negative, he was diagnosed with remitting seronegative symmetrical synovitis with pitting edema syndrome. At the same time, computed tomography revealed a nodule suspicious of lung carcinoma in the right lower lobe. Right lower lobe lobectomy was performed, and the nodule was diagnosed as adenocarcinoma. Pathologically, pleural invasion and visceral pleural dissemination were detected, and the tumor was diagnosed as a primary lung carcinoma, p-T2aN0M1a, stage IV. During the preoperative interval, the remitting seronegative symmetrical synovitis with pitting edema syndrome had been successfully treated with prednisolone 20 mg/day, which was later reduced to 6 mg/day. Eighteen months after surgery, the patient's carcinoembryonic antigen levels increased, and the same symptoms recurred, this time more severely. We performed cranial magnetic resonance imaging and whole body positron emission tomography, but we did not detect any cancer recurrence. To treat the recurred remitting seronegative symmetrical synovitis with pitting edema syndrome, the patient has required not only prednisolone, but also azathioprine; however, the symptoms have not been controlled effectively. In our case, matrix metalloproteinase-3 levels were elevated, as shown in the tumor cells by immunohistochemistry. If higher matrix metalloproteinase-3 levels cause the symptoms, in our case, then remitting seronegative symmetrical synovitis syndrome might be considered a paraneoplastic syndrome. However, we could not conclusively determine if the subsequent reduction in matrix metalloproteinase-3 levels was the result of the surgery or the prednisolone treatment. Furthermore, based on the patient's progress following surgery, it is still not clear if the remitting seronegative symmetrical synovitis with pitting edema syndrome complicated with primary lung cancer in this case may be a paraneoplastic syndrome.