DECT Diagnosis of Gouty Tophi with Normal Uric Acid: A Case Report

DECT Diagnosis of Gouty Tophi with Normal Uric Acid: A Case Report | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report DECT Diagnosis of Gouty Tophi with Normal Uric Acid: A Case Report Kyosuke Ota, Satoshi Yabusaki This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8907954/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Introduction Gouty tophi are chronic granulomatous structures composed of monosodium urate (MSU) crystals [1]. While arthrocentesis is the diagnostic gold standard, it is invasive and prone to sampling errors [2]. Dual energy computed tomography (DECT) addresses these limitations by utilizing the distinct X-ray attenuation properties of MSU at different energy levels. Case Presentation A 59-year-old male presented with foot swelling. Based on clinical findings, cellulitis and osteomyelitis were initially suspected, and antibiotic therapy was commenced. Initial magnetic resonance imaging also supported the suspicion of osteomyelitis (Fig.1). However, the symptoms showed no significant improvement until dual energy computed tomography (DECT) identified monosodium urate (MSU) crystals (Fig.2), confirming the diagnosis of gouty tophi. The patient’s symptoms resolved following surgical debridement. Discussion DECT enables precise material decomposition through spectral data analysis, allowing for non-invasive differentiation of MSU from calcium or soft tissues. The technology is highly reliable, with a meta-analysis reporting a sensitivity of 84.7% and specificity of 93.7% for gout diagnosis [3]. DECT’s ability to characterize the chemical composition of periarticular masses is invaluable when clinical markers are atypical or unavailable. By confirming the diagnosis non-invasively, DECT helps prevent misdiagnosis and avoid inappropriate management, such as prolonged antibiotic therapy for a potential infection or unnecessary surgical intervention. Gouty tophi monosodium urate dual energy computed tomography periarticular masses case report Figures Figure 1 Figure 2 Introduction Gouty tophi are chronic granulomatous structures composed of monosodium urate (MSU) crystals [ 1 ]. While arthrocentesis is the diagnostic gold standard, it is invasive and prone to sampling errors [ 2 ]. Dual energy computed tomography (DECT) addresses these limitations by utilizing the distinct X-ray attenuation properties of MSU at different energy levels. Case Presentation A 59-year-old male presented with foot swelling. Based on clinical findings, cellulitis and osteomyelitis were initially suspected, and antibiotic therapy was commenced. Initial magnetic resonance imaging also supported the suspicion of osteomyelitis (Fig. 1 ). However, the symptoms showed no significant improvement until dual energy computed tomography (DECT) identified monosodium urate (MSU) crystals (Fig. 2 ), confirming the diagnosis of gouty tophi. The patient’s symptoms resolved following surgical debridement. Discussion DECT enables precise material decomposition through spectral data analysis, allowing for non-invasive differentiation of MSU from calcium or soft tissues. The technology is highly reliable, with a meta-analysis reporting a sensitivity of 84.7% and specificity of 93.7% for gout diagnosis [ 3 ]. DECT’s ability to characterize the chemical composition of periarticular masses is invaluable when clinical markers are atypical or unavailable. By confirming the diagnosis non-invasively, DECT helps prevent misdiagnosis and avoid inappropriate management, such as prolonged antibiotic therapy for a potential infection or unnecessary surgical intervention. Declarations Funding No Competing Interest The authors declare that they have no conflict of interest. Ethics approval This study was approved by the Ethics Committee of Tomakomai City Hospital in accordance with the Declaration of Helsinki. Consent to Participate Informed consent was waived by the Ethics Committee of Tomakomai City Hospital due to the retrospective nature of this case report. Consent to Publish Informed consent for the publication of this case report was waived by the Ethics Committee of Tomakomai City Hospital. Data Availability All data generated or analyzed during this study are included in this published article. Acknowledgments of people, grants, funds, etc. No References Chhana A, Dalbeth N. The gouty tophus: a review. Curr Rheumatol Rep. 2015;17:19. Neogi T, Jansen TL, Dalbeth N, et al. 2015 Gout classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Ann Rheum Dis. 2015;74:1789–98. Lee YH, Song GG. Diagnostic accuracy of dual-energy computed tomography in the diagnosis of gout: A meta-analysis. Semin Arthritis Rheum. 2017;47:95–101. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8907954","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":616520747,"identity":"44795349-f46c-4da1-8813-ffacd21d0e37","order_by":0,"name":"Kyosuke Ota","email":"","orcid":"","institution":"Tomakomai City Hospital","correspondingAuthor":false,"prefix":"","firstName":"Kyosuke","middleName":"","lastName":"Ota","suffix":""},{"id":616520749,"identity":"0b07b5ee-9dcd-4cbb-aee9-76145d11301b","order_by":1,"name":"Satoshi Yabusaki","email":"data:image/png;base64,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","orcid":"","institution":"Tomakomai City Hospital","correspondingAuthor":true,"prefix":"","firstName":"Satoshi","middleName":"","lastName":"Yabusaki","suffix":""}],"badges":[],"createdAt":"2026-02-18 09:53:30","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8907954/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8907954/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106405746,"identity":"a5a896d0-e4a3-4bd7-84bf-46d73e365d3c","added_by":"auto","created_at":"2026-04-08 09:28:21","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":390475,"visible":true,"origin":"","legend":"\u003cp\u003e(a) T1-weighted and (b) Short Tau Inversion Recovery (STIR) images of the left first toe. Periarticular masses with bone erosion and increased marrow signal intensity (arrowheads) mimic osteomyelitis.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8907954/v1/29c148b6d499e98cb301c4d4.png"},{"id":106405022,"identity":"e7f692ca-a21f-4ec7-a0f3-f0c1d5b569bf","added_by":"auto","created_at":"2026-04-08 09:20:25","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":186849,"visible":true,"origin":"","legend":"\u003cp\u003eColor-coded spectral computed tomography (CT) image (fusion of bone window and monosodium urate (MSU) map) demonstrates MSU deposits (orange-to-red areas) within the masses, confirming the diagnosis non-invasively.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8907954/v1/dd120f1ee4c36e6bfe321a4c.png"},{"id":109164223,"identity":"9068e43b-c939-44e3-a469-b3f877451f33","added_by":"auto","created_at":"2026-05-13 08:02:44","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":857258,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8907954/v1/a7af47a9-7455-4ba3-b98b-7fde6d14d673.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"DECT Diagnosis of Gouty Tophi with Normal Uric Acid: A Case Report","fulltext":[{"header":"Introduction","content":"\u003cp\u003eGouty tophi are chronic granulomatous structures composed of monosodium urate (MSU) crystals [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. While arthrocentesis is the diagnostic gold standard, it is invasive and prone to sampling errors [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Dual energy computed tomography (DECT) addresses these limitations by utilizing the distinct X-ray attenuation properties of MSU at different energy levels.\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eA 59-year-old male presented with foot swelling. Based on clinical findings, cellulitis and osteomyelitis were initially suspected, and antibiotic therapy was commenced. Initial magnetic resonance imaging also supported the suspicion of osteomyelitis (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). However, the symptoms showed no significant improvement until dual energy computed tomography (DECT) identified monosodium urate (MSU) crystals (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), confirming the diagnosis of gouty tophi. The patient\u0026rsquo;s symptoms resolved following surgical debridement.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eDECT enables precise material decomposition through spectral data analysis, allowing for non-invasive differentiation of MSU from calcium or soft tissues. The technology is highly reliable, with a meta-analysis reporting a sensitivity of 84.7% and specificity of 93.7% for gout diagnosis [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. DECT\u0026rsquo;s ability to characterize the chemical composition of periarticular masses is invaluable when clinical markers are atypical or unavailable. By confirming the diagnosis non-invasively, DECT helps prevent misdiagnosis and avoid inappropriate management, such as prolonged antibiotic therapy for a potential infection or unnecessary surgical intervention.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e\n\u003cp\u003eCompeting Interest\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no conflict of interest.\u003c/p\u003e\n\u003cp\u003eEthics approval\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Tomakomai City Hospital in accordance with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003eConsent to Participate\u003c/p\u003e\n\u003cp\u003eInformed consent was waived by the Ethics Committee of Tomakomai City Hospital due to the retrospective nature of this case report.\u003c/p\u003e\n\u003cp\u003eConsent to Publish\u003c/p\u003e\n\u003cp\u003eInformed consent for the publication of this case report was waived by the Ethics Committee of Tomakomai City Hospital.\u003c/p\u003e\n\u003cp\u003eData Availability\u003c/p\u003e\n\u003cp\u003eAll data generated or analyzed during this study are included in this published article.\u003cp\u003eAcknowledgments of people, grants, funds, etc.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eChhana A, Dalbeth N. The gouty tophus: a review. Curr Rheumatol Rep. 2015;17:19.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNeogi T, Jansen TL, Dalbeth N, et al. 2015 Gout classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Ann Rheum Dis. 2015;74:1789\u0026ndash;98.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLee YH, Song GG. Diagnostic accuracy of dual-energy computed tomography in the diagnosis of gout: A meta-analysis. Semin Arthritis Rheum. 2017;47:95\u0026ndash;101.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Gouty tophi, monosodium urate, dual energy computed tomography, periarticular masses, case report","lastPublishedDoi":"10.21203/rs.3.rs-8907954/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8907954/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIntroduction Gouty tophi are chronic granulomatous structures composed of monosodium urate (MSU) crystals [1]. While arthrocentesis is the diagnostic gold standard, it is invasive and prone to sampling errors [2]. Dual energy computed tomography (DECT) addresses these limitations by utilizing the distinct X-ray attenuation properties of MSU at different energy levels.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCase Presentation A 59-year-old male presented with foot swelling. Based on clinical findings, cellulitis and osteomyelitis were initially suspected, and antibiotic therapy was commenced. Initial magnetic resonance imaging also supported the suspicion of osteomyelitis (Fig.1). However, the symptoms showed no significant improvement until dual energy computed tomography (DECT) identified monosodium urate (MSU) crystals (Fig.2), confirming the diagnosis of gouty tophi. The patient’s symptoms resolved following surgical debridement.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDiscussion DECT enables precise material decomposition through spectral data analysis, allowing for non-invasive differentiation of MSU from calcium or soft tissues. The technology is highly reliable, with a meta-analysis reporting a sensitivity of 84.7% and specificity of 93.7% for gout diagnosis [3]. DECT’s ability to characterize the chemical composition of periarticular masses is invaluable when clinical markers are atypical or unavailable. By confirming the diagnosis non-invasively, DECT helps prevent misdiagnosis and avoid inappropriate management, such as prolonged antibiotic therapy for a potential infection or unnecessary surgical intervention.\u003c/p\u003e","manuscriptTitle":"DECT Diagnosis of Gouty Tophi with Normal Uric Acid: A Case Report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-05 17:10:40","doi":"10.21203/rs.3.rs-8907954/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"78a26d02-9dad-4ca2-b5ea-9c7ead6f0b19","owner":[],"postedDate":"April 5th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Withdrawn","date":"2026-05-13T07:41:51+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T08:01:19+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-05 17:10:40","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8907954","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8907954","identity":"rs-8907954","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}