Microscopic polyangiitis (MPA) is an antineutrophil cytoplasmic antibody-associated vasculitis characterised by inflammation in small vessels. Avacopan, an oral C5a receptor inhibitor, has demonstrated efficacy in inducing and sustaining remission in MPA, with the added benefit of reducing glucocorticoid exposure and associated toxicities. Among adverse effects, liver injury is the most common, occurring in 16.7-40.9% of cases in the Japanese cohorts. Drug-induced hypersensitivity syndrome (DIHS) is a rare adverse effect caused by avacopan. We describe a case of a 77-year-old woman with MPA who was initiated on prednisolone 30 mg/day and avacopan as the induction therapy. Disease activity of MPA improved with this induction therapy. However, 7 weeks after initiating avacopan, she developed significant liver dysfunction. Despite the discontinuation of avacopan, she subsequently presented with fever and a generalised rash, leading to a diagnosis of DIHS. Laboratory data revealed reactivation of human herpesvirus 6. Despite the discontinuation of avacopan, liver injury persisted, and liver biopsy findings were consistent with drug-induced hepatitis. Long-term hospitalisation was required for improvement in skin symptoms and liver function. This case highlights a rare but serious adverse event of avacopan in MPA. During avacopan therapy, it is necessary to monitor for delayed severe skin symptoms such as DIHS.
{"title":"Unexpected adverse event caused by avacopan: a case of drug-induced hypersensitivity syndrome in microscopic polyangiitis.","authors":"Hiroki Nibu, Haruki Matsumoto, Yuto Ishizaki, Eisuke Kameoka, Hiroki Irie, Naoki Konno, Yukiko Kanno, Kenta Kodama, Masahito Kuroda, Yoshikazu Motoki, Kazuhiro Tasaki, Tomoyuki Asano, Shuzo Sato, Masayuki Miyata","doi":"10.1093/mrcr/rxaf054","DOIUrl":"10.1093/mrcr/rxaf054","url":null,"abstract":"<p><p>Microscopic polyangiitis (MPA) is an antineutrophil cytoplasmic antibody-associated vasculitis characterised by inflammation in small vessels. Avacopan, an oral C5a receptor inhibitor, has demonstrated efficacy in inducing and sustaining remission in MPA, with the added benefit of reducing glucocorticoid exposure and associated toxicities. Among adverse effects, liver injury is the most common, occurring in 16.7-40.9% of cases in the Japanese cohorts. Drug-induced hypersensitivity syndrome (DIHS) is a rare adverse effect caused by avacopan. We describe a case of a 77-year-old woman with MPA who was initiated on prednisolone 30 mg/day and avacopan as the induction therapy. Disease activity of MPA improved with this induction therapy. However, 7 weeks after initiating avacopan, she developed significant liver dysfunction. Despite the discontinuation of avacopan, she subsequently presented with fever and a generalised rash, leading to a diagnosis of DIHS. Laboratory data revealed reactivation of human herpesvirus 6. Despite the discontinuation of avacopan, liver injury persisted, and liver biopsy findings were consistent with drug-induced hepatitis. Long-term hospitalisation was required for improvement in skin symptoms and liver function. This case highlights a rare but serious adverse event of avacopan in MPA. During avacopan therapy, it is necessary to monitor for delayed severe skin symptoms such as DIHS.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144857295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Traditionally, patients with rheumatic diseases, such as rheumatoid arthritis (RA), were considered unsuitable for joint-sparing surgery. In the present study, we report on bilateral knee joints affected by psoriatic arthritis coexisting with osteoarthritis, with good, albeit short-term, results. A 62-year-old woman was treated for psoriatic arthritis with a biologic (adalimumab). The Disease Activity in Psoriatic Arthritis index was 7.24, indicating low disease activity. She had been suffering from bilateral knee pain for some time and was treated conservatively by her local doctor, but the pain persisted, and she came to visit us. At the initial visit, tenderness in the medial joint line of both knees and hydrarthrosis in the right knee were observed. Preoprative radiographs at the time of the initial examination showed medial-type osteoarthritis in both knees. First, interlocking closed wedge high tibial osteotomy (CWHTO) was performed on the right knee. This was followed 1 year later by right knee implant removal and interlocking CWHTO on the left knee, with implant removal on the left knee 1 year after that. In both knees preoperatively and postoperatively, the joint range of motion and the Knee Injury and Osteoarthritis Outcome Score total improved Considering the patient's background, we considered high tibial osteotomy if the disease activity was controlled. However, if the disease worsens in the future, joint destruction may occur, so careful follow-up is necessary.
{"title":"A case of high tibial osteotomy in a patient with psoriatic arthritis.","authors":"Mikiro Koga, Akira Maeyama, Tetsuro Ishimatsu, Tomonobu Hagio, Terufumi Shibata, Yutaro Yamasaki, Yuki Sugino, Takuaki Yamamoto","doi":"10.1093/mrcr/rxaf007","DOIUrl":"10.1093/mrcr/rxaf007","url":null,"abstract":"<p><p>Traditionally, patients with rheumatic diseases, such as rheumatoid arthritis (RA), were considered unsuitable for joint-sparing surgery. In the present study, we report on bilateral knee joints affected by psoriatic arthritis coexisting with osteoarthritis, with good, albeit short-term, results. A 62-year-old woman was treated for psoriatic arthritis with a biologic (adalimumab). The Disease Activity in Psoriatic Arthritis index was 7.24, indicating low disease activity. She had been suffering from bilateral knee pain for some time and was treated conservatively by her local doctor, but the pain persisted, and she came to visit us. At the initial visit, tenderness in the medial joint line of both knees and hydrarthrosis in the right knee were observed. Preoprative radiographs at the time of the initial examination showed medial-type osteoarthritis in both knees. First, interlocking closed wedge high tibial osteotomy (CWHTO) was performed on the right knee. This was followed 1 year later by right knee implant removal and interlocking CWHTO on the left knee, with implant removal on the left knee 1 year after that. In both knees preoperatively and postoperatively, the joint range of motion and the Knee Injury and Osteoarthritis Outcome Score total improved Considering the patient's background, we considered high tibial osteotomy if the disease activity was controlled. However, if the disease worsens in the future, joint destruction may occur, so careful follow-up is necessary.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143030659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rajaie Namas, Sarah Al Qassimi, Jawahir Alameri, Fatema Alawadhi, Esat Memisoglu, Ahlam Almarzooqi
Diffuse idiopathic skeletal hyperostosis (DISH) and axial spondyloarthritis (axSpA) share similarities in both clinical presentation and radiological findings, making the diagnostic process challenging. We report the case of a 30-year-old male with a long-standing history of back pain with an initial diagnosis of young-onset DISH. However, a diagnosis of axSpA was ultimately pursued based on his age and clinical presentation. This was further supported by improvement in both Ankylosing Spondylitis Disease Activity Score with Erythrocyte Sedimentation Rate (ASDAS-ESR) and Ankylosing Spondylitis Disease Activity Score with C-Reactive Protein (ASDAS-CRP) scores at his 6- and 12-month follow-ups on ixekizumab. Early and accurate diagnosis of axSpA, followed by appropriate treatment, is essential in preventing complications and improving patient outcomes.
{"title":"Young onset chronic inflammatory back pain: A diagnostic dilemma between axial spondylitis and diffuse idiopathic skeletal hyperostosis.","authors":"Rajaie Namas, Sarah Al Qassimi, Jawahir Alameri, Fatema Alawadhi, Esat Memisoglu, Ahlam Almarzooqi","doi":"10.1093/mrcr/rxaf002","DOIUrl":"10.1093/mrcr/rxaf002","url":null,"abstract":"<p><p>Diffuse idiopathic skeletal hyperostosis (DISH) and axial spondyloarthritis (axSpA) share similarities in both clinical presentation and radiological findings, making the diagnostic process challenging. We report the case of a 30-year-old male with a long-standing history of back pain with an initial diagnosis of young-onset DISH. However, a diagnosis of axSpA was ultimately pursued based on his age and clinical presentation. This was further supported by improvement in both Ankylosing Spondylitis Disease Activity Score with Erythrocyte Sedimentation Rate (ASDAS-ESR) and Ankylosing Spondylitis Disease Activity Score with C-Reactive Protein (ASDAS-CRP) scores at his 6- and 12-month follow-ups on ixekizumab. Early and accurate diagnosis of axSpA, followed by appropriate treatment, is essential in preventing complications and improving patient outcomes.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143019147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Familial Mediterranean fever (FMF) is an autoinflammatory disease associated with mutations in MEFV, which encodes pyrin. Patients with FMF present intermittent high fever with elevated inflammatory markers during periodic attacks. While some forms of vasculitis, including immunoglobulin A (IgA) vasculitis and polyarteritis nodosa have been reported in some patients with FMF, Takayasu arteritis (TAK) rarely associated with FMF. In addition, little has been known about the clinical features and pathogenesis of vasculitis with FMF. Here we report a case of FMF with TAK. Our case is remarkable on his clinical course of neck pain with low-grade elevation of serum C-reactive protein during interictal periods of fever attacks. He possessed the dual genetic background of a pathogenic variant of p.M694V in MEFV and HLA-B*52:01, which is susceptible to TAK. Although he was refractory to the combination therapy with colchicine, corticosteroids, and methotrexate, tocilizumab was effective for both recurrent fever attacks and vasculitis. Previous four reports of FMF with TAK as well as our case suggest the pathogenic MEFV mutation could be a predisposing or additional factor that modify the development of TAK. Since both the activity of FMF and TAK responded to tocilizumab in our case, the pathogenesis shared between FMF and TAK was indicated.
{"title":"Successful treatment with tocilizumab in a case of familial Mediterranean fever with Takayasu arteritis.","authors":"Saeka Kondo, Natsuka Umezawa, Yasuhiro Tagawa, Shinsuke Yasuda","doi":"10.1093/mrcr/rxaf027","DOIUrl":"10.1093/mrcr/rxaf027","url":null,"abstract":"<p><p>Familial Mediterranean fever (FMF) is an autoinflammatory disease associated with mutations in MEFV, which encodes pyrin. Patients with FMF present intermittent high fever with elevated inflammatory markers during periodic attacks. While some forms of vasculitis, including immunoglobulin A (IgA) vasculitis and polyarteritis nodosa have been reported in some patients with FMF, Takayasu arteritis (TAK) rarely associated with FMF. In addition, little has been known about the clinical features and pathogenesis of vasculitis with FMF. Here we report a case of FMF with TAK. Our case is remarkable on his clinical course of neck pain with low-grade elevation of serum C-reactive protein during interictal periods of fever attacks. He possessed the dual genetic background of a pathogenic variant of p.M694V in MEFV and HLA-B*52:01, which is susceptible to TAK. Although he was refractory to the combination therapy with colchicine, corticosteroids, and methotrexate, tocilizumab was effective for both recurrent fever attacks and vasculitis. Previous four reports of FMF with TAK as well as our case suggest the pathogenic MEFV mutation could be a predisposing or additional factor that modify the development of TAK. Since both the activity of FMF and TAK responded to tocilizumab in our case, the pathogenesis shared between FMF and TAK was indicated.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This report describes two cases of implant-stable traumatic periprosthetic fractures after total ankle arthroplasty in patients with rheumatoid arthritis. One case with a low body mass index (14 kg/m2) achieved complete bone union with the use of an external fixator, while the other case with a high body mass index (32.83 kg/m2) failed to achieve bone union with the external fixator; however, complete union was achieved utilising secondary internal plate fixation. Although open reduction and internal fixation using a plate is the standard procedure in implant-stable periprosthetic fracture cases, fixation using an external fixator might be suitable for patients with rheumatoid arthritis with low body weight and low body mass index, from the perspective of preventing surgical site complications.
{"title":"Utility of external fixation for traumatic periprosthetic fracture after total ankle arthroplasty in patients with rheumatoid arthritis: A report of two cases.","authors":"Gensuke Okamura, Takaaki Noguchi, Yuki Etani, Kosuke Ebina, Seiji Okada, Jun Hashimoto, Makoto Hirao","doi":"10.1093/mrcr/rxae084","DOIUrl":"10.1093/mrcr/rxae084","url":null,"abstract":"<p><p>This report describes two cases of implant-stable traumatic periprosthetic fractures after total ankle arthroplasty in patients with rheumatoid arthritis. One case with a low body mass index (14 kg/m2) achieved complete bone union with the use of an external fixator, while the other case with a high body mass index (32.83 kg/m2) failed to achieve bone union with the external fixator; however, complete union was achieved utilising secondary internal plate fixation. Although open reduction and internal fixation using a plate is the standard procedure in implant-stable periprosthetic fracture cases, fixation using an external fixator might be suitable for patients with rheumatoid arthritis with low body weight and low body mass index, from the perspective of preventing surgical site complications.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142824885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The involvement of the central nervous system with granulomatosis with polyangiitis (GPA) is uncommon, and the formation of intracranial mass lesions is particularly rare. We describe the case of a Japanese woman in her thirties with GPA initially limited to the upper respiratory tract. Twelve years after the disease was onset, brain magnetic resonance imaging revealed a lobulated mass in the frontal lobe, and computed tomography findings suggested direct extension of granulomatous inflammation from the paranasal sinuses through the cribriform plate. Due to the risk of infection associated with cribriform plate destruction, surgical resection was performed for both diagnostic and preventive purposes. Histopathological examination of the resected intracranial lesion revealed necrotising granulomas without evidence of infection, consistent with GPA. Postoperatively, a moderate dose of prednisolone and rituximab was administered, resulting in clinical and serological remission. This case highlights a rare intracranial manifestation of GPA caused by direct contiguous spread from the paranasal sinuses, which can occur in the absence of systemic symptoms. Although sinonasal involvement is typically regarded as non-severe, the presence of bony destruction may signal a potentially organ-threatening course.
{"title":"Intracranial invasion of granulomatous sinusitis: report of a rare case of granulomatosis with polyangiitis.","authors":"Takumi Saito, Wataru Nakamura, Yujin Nishioka, Erika Matsuda, Mariko Yamana, Rina Takahashi, Masahiro Kogami, Ayako Makiyama, Goh Murayama, Yoshiyuki Abe, Takuo Hayashi, Makio Kusaoi, Kurisu Tada, Ken Yamaji, Naoto Tamura","doi":"10.1093/mrcr/rxaf058","DOIUrl":"10.1093/mrcr/rxaf058","url":null,"abstract":"<p><p>The involvement of the central nervous system with granulomatosis with polyangiitis (GPA) is uncommon, and the formation of intracranial mass lesions is particularly rare. We describe the case of a Japanese woman in her thirties with GPA initially limited to the upper respiratory tract. Twelve years after the disease was onset, brain magnetic resonance imaging revealed a lobulated mass in the frontal lobe, and computed tomography findings suggested direct extension of granulomatous inflammation from the paranasal sinuses through the cribriform plate. Due to the risk of infection associated with cribriform plate destruction, surgical resection was performed for both diagnostic and preventive purposes. Histopathological examination of the resected intracranial lesion revealed necrotising granulomas without evidence of infection, consistent with GPA. Postoperatively, a moderate dose of prednisolone and rituximab was administered, resulting in clinical and serological remission. This case highlights a rare intracranial manifestation of GPA caused by direct contiguous spread from the paranasal sinuses, which can occur in the absence of systemic symptoms. Although sinonasal involvement is typically regarded as non-severe, the presence of bony destruction may signal a potentially organ-threatening course.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145088667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Macrophage migration inhibitory factor as a potential 'missing important factor' driving inflammatory arthritis in adrenocorticotropic hormone deficiency.","authors":"Lisa Wang, Akihiro Nakamura","doi":"10.1093/mrcr/rxae070","DOIUrl":"10.1093/mrcr/rxae070","url":null,"abstract":"","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142831592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Schnitzler syndrome (SchS) is a rare autoinflammatory disorder characterised by recurrent urticaria, monoclonal gammopathy, fever, and arthralgia. We herein report a case of SchS complicated by rheumatoid arthritis (RA). A 78-year-old man presented to our hospital with fever, myalgia, and urticaria, each lasting for ~1 week over the past 8 years. He was diagnosed with SchS based on monoclonal immunoglobulin G gammopathy, chronic urticaria, an intermittent fever, arthritis, high inflammatory markers, and neutrophil infiltration in the dermis on skin biopsy. Although colchicine improved the symptoms slightly, the patient subsequently developed arthritis and was diagnosed with RA based on elevated anti-cyclic citrullinated peptide antibody and rheumatoid factor levels. Methotrexate (MTX), a first-line therapy for RA, was initiated, resulting in a remarkable improvement in both RA and SchS symptoms. This case highlights the rare coexistence of SchS and RA as well as the efficacy of MTX in treating both conditions. Although interleukin (IL)-1 inhibitors are considered the most effective treatment for SchS, they are not approved for SchS in Japan and are expensive. The efficacy of IL-6 inhibitors in SchS has also been reported, and MTX suppresses inflammatory cytokines, including IL-1 and IL-6. As shown in our case, drugs that modulate IL-6 levels, such as MTX, may be a viable treatment option for SchS.
{"title":"A case of Schnitzler syndrome complicated by rheumatoid arthritis treated with methotrexate.","authors":"Kensuke Irino, Yu Kochi, Sakurako Imamura, Chika Nabeshima, Naoya Oka, Takuya Sawabe","doi":"10.1093/mrcr/rxaf026","DOIUrl":"10.1093/mrcr/rxaf026","url":null,"abstract":"<p><p>Schnitzler syndrome (SchS) is a rare autoinflammatory disorder characterised by recurrent urticaria, monoclonal gammopathy, fever, and arthralgia. We herein report a case of SchS complicated by rheumatoid arthritis (RA). A 78-year-old man presented to our hospital with fever, myalgia, and urticaria, each lasting for ~1 week over the past 8 years. He was diagnosed with SchS based on monoclonal immunoglobulin G gammopathy, chronic urticaria, an intermittent fever, arthritis, high inflammatory markers, and neutrophil infiltration in the dermis on skin biopsy. Although colchicine improved the symptoms slightly, the patient subsequently developed arthritis and was diagnosed with RA based on elevated anti-cyclic citrullinated peptide antibody and rheumatoid factor levels. Methotrexate (MTX), a first-line therapy for RA, was initiated, resulting in a remarkable improvement in both RA and SchS symptoms. This case highlights the rare coexistence of SchS and RA as well as the efficacy of MTX in treating both conditions. Although interleukin (IL)-1 inhibitors are considered the most effective treatment for SchS, they are not approved for SchS in Japan and are expensive. The efficacy of IL-6 inhibitors in SchS has also been reported, and MTX suppresses inflammatory cytokines, including IL-1 and IL-6. As shown in our case, drugs that modulate IL-6 levels, such as MTX, may be a viable treatment option for SchS.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144164399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Microscopic polyangiitis (MPA), a form of ANCA-associated vasculitis (AAV), can present a diagnostic challenge when it manifests with atypical symptoms. We report a case of MPA where the predominant clinical feature was myalgia with normal creatine kinase levels, underscoring the importance of a comprehensive diagnostic approach. A 60-year-old male presented with bilateral lower leg myalgia and gait disturbance. Physical examination revealed muscle tenderness and weakness. Magnetic resonance imaging (MRI) with fat-suppressed T2-weighted imaging showed heterogeneous high signal intensity in the lower limb muscles, suggestive of myositis. However, laboratory investigations found normal serum creatine kinase levels, and all tested myositis-specific autoantibodies were negative. A muscle biopsy yielded inconclusive results. In contrast, serology was positive for myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA). Despite preserved kidney function and unremarkable urinalysis, a kidney biopsy was performed, which revealed fibrinoid necrosis in small arteries. This led to a definitive diagnosis of MPA. This case highlights that MPA should be considered a key differential diagnosis in patients presenting with myalgia, particularly in the presence of a positive MPO-ANCA serology. While muscle manifestations occur in ~20% of AAV cases, they are not included in the current classification criteria. Our findings underscore that kidney biopsy remains a critical diagnostic tool for establishing a definitive diagnosis of MPA, even when renal symptoms are minimal, facilitating timely and appropriate immunosuppressive therapy.
{"title":"Myalgia as initial presentation of microscopic polyangiitis: diagnostic utility of kidney biopsy.","authors":"Miyu Wakatsuki, Yuki Oba, Junko Kanda-Kikuchi, Kei Kono, Masayuki Yamanouchi, Tatsuya Suwabe, Yoshifumi Ubara, Izumi Sugimoto, Kenichi Ohashi, Naoki Sawa","doi":"10.1093/mrcr/rxaf062","DOIUrl":"10.1093/mrcr/rxaf062","url":null,"abstract":"<p><p>Microscopic polyangiitis (MPA), a form of ANCA-associated vasculitis (AAV), can present a diagnostic challenge when it manifests with atypical symptoms. We report a case of MPA where the predominant clinical feature was myalgia with normal creatine kinase levels, underscoring the importance of a comprehensive diagnostic approach. A 60-year-old male presented with bilateral lower leg myalgia and gait disturbance. Physical examination revealed muscle tenderness and weakness. Magnetic resonance imaging (MRI) with fat-suppressed T2-weighted imaging showed heterogeneous high signal intensity in the lower limb muscles, suggestive of myositis. However, laboratory investigations found normal serum creatine kinase levels, and all tested myositis-specific autoantibodies were negative. A muscle biopsy yielded inconclusive results. In contrast, serology was positive for myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA). Despite preserved kidney function and unremarkable urinalysis, a kidney biopsy was performed, which revealed fibrinoid necrosis in small arteries. This led to a definitive diagnosis of MPA. This case highlights that MPA should be considered a key differential diagnosis in patients presenting with myalgia, particularly in the presence of a positive MPO-ANCA serology. While muscle manifestations occur in ~20% of AAV cases, they are not included in the current classification criteria. Our findings underscore that kidney biopsy remains a critical diagnostic tool for establishing a definitive diagnosis of MPA, even when renal symptoms are minimal, facilitating timely and appropriate immunosuppressive therapy.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145484403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A 55-year-old woman presented to our hospital with arthritis of the hands. Tests for anti-cyclic citrullinated peptide antibodies and rheumatic factor were negative, and seronegative rheumatoid arthritis was diagnosed. The patient was treated with methotrexate and certolizumab (tumour-necrosis factor-α inhibitor). Disease activity was controlled with the drugs, but after 14 months, erythematous plaques with scaling appeared on the palms and feet. Skin biopsy revealed bullous lesions with aseptic abscess formation, leading to the diagnosis of palmoplantar pustulosis and pustulotic arthro-osteitis. The patient had a family history of palmoplantar pustulosis. The skin lesions improved after discontinuation of certolizumab and treatment with ointments and phototherapy. This case suggests that tumour-necrosis factor-α inhibitors may potentially trigger palmoplantar pustulosis in patients with a family history (genetic factor) of the condition.
{"title":"A patient with certolizumab pegol-induced palmoplantar pustulosis or pustulotic arthro-osteitis: a case report.","authors":"Ayaka Hane, Naoki Sawa, Yuki Oba, Shigekazu Kurihara, Akinari Sekine, Masayuki Yamanouchi, Tatsuya Suwabe, Eiko Hasegawa, Akiko Kishi, Nobukazu Hayashi, Kei Kono, Yutaka Takazawa, Takehiko Wada, Yoshifumi Ubara","doi":"10.1093/mrcr/rxaf069","DOIUrl":"10.1093/mrcr/rxaf069","url":null,"abstract":"<p><p>A 55-year-old woman presented to our hospital with arthritis of the hands. Tests for anti-cyclic citrullinated peptide antibodies and rheumatic factor were negative, and seronegative rheumatoid arthritis was diagnosed. The patient was treated with methotrexate and certolizumab (tumour-necrosis factor-α inhibitor). Disease activity was controlled with the drugs, but after 14 months, erythematous plaques with scaling appeared on the palms and feet. Skin biopsy revealed bullous lesions with aseptic abscess formation, leading to the diagnosis of palmoplantar pustulosis and pustulotic arthro-osteitis. The patient had a family history of palmoplantar pustulosis. The skin lesions improved after discontinuation of certolizumab and treatment with ointments and phototherapy. This case suggests that tumour-necrosis factor-α inhibitors may potentially trigger palmoplantar pustulosis in patients with a family history (genetic factor) of the condition.</p>","PeriodicalId":94146,"journal":{"name":"Modern rheumatology case reports","volume":" ","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145491141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}