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    <Journal>
      <PublisherName>jmedicalcasereports</PublisherName>
      <JournalTitle>Frontiers in Medical Case Reports</JournalTitle>
      <PISSN>I</PISSN>
      <EISSN>S</EISSN>
      <Volume-Issue>Volume 6; Issue 4</Volume-Issue>
      <PartNumber/>
      <IssueTopic>Multidisciplinary</IssueTopic>
      <IssueLanguage>English</IssueLanguage>
      <Season>(Jul-Aug, 2025)</Season>
      <SpecialIssue>N</SpecialIssue>
      <SupplementaryIssue>N</SupplementaryIssue>
      <IssueOA>Y</IssueOA>
      <PubDate>
        <Year>-0001</Year>
        <Month>11</Month>
        <Day>30</Day>
      </PubDate>
      <ArticleType>Medical Case Reports</ArticleType>
      <ArticleTitle>Respiratory Colonization or Infection? Unraveling The Origin of Methicillin-Sensitive Staphylococcus Aureus Bacteremia in An Immunosuppressed Patient with Systemic Lupus Erythematosus</ArticleTitle>
      <SubTitle/>
      <ArticleLanguage>English</ArticleLanguage>
      <ArticleOA>Y</ArticleOA>
      <FirstPage>1</FirstPage>
      <LastPage>8</LastPage>
      <AuthorList>
        <Author>
          <FirstName>Ling</FirstName>
          <LastName>Qin</LastName>
          <AuthorLanguage>English</AuthorLanguage>
          <Affiliation/>
          <CorrespondingAuthor>N</CorrespondingAuthor>
          <ORCID/>
          <FirstName>Shiyu</FirstName>
          <LastName>Chen</LastName>
          <AuthorLanguage>English</AuthorLanguage>
          <Affiliation/>
          <CorrespondingAuthor>Y</CorrespondingAuthor>
          <ORCID/>
          <FirstName>Lina</FirstName>
          <LastName>Guo</LastName>
          <AuthorLanguage>English</AuthorLanguage>
          <Affiliation/>
          <CorrespondingAuthor>Y</CorrespondingAuthor>
          <ORCID/>
          <FirstName>Chao</FirstName>
          <LastName>Li</LastName>
          <AuthorLanguage>English</AuthorLanguage>
          <Affiliation/>
          <CorrespondingAuthor>Y</CorrespondingAuthor>
          <ORCID/>
          <FirstName>Ying</FirstName>
          <LastName>Ge</LastName>
          <AuthorLanguage>English</AuthorLanguage>
          <Affiliation/>
          <CorrespondingAuthor>Y</CorrespondingAuthor>
          <ORCID/>
        </Author>
      </AuthorList>
      <DOI/>
      <Abstract>This case report describes the clinical course of methicillin-sensitive Staphylococcus Aureus (MSSA) bacteremia in a 44- year old female patient with systemic lupus erythematosus (SLE) under immunosuppressive therapy. The patient was initially hospitalized due to active SLE. After the disease activity was controlled, she developed fever and hypoxemia. Blood cultures and lower respiratory tract secretions both yielded MSSA. Whole-genome sequencing revealed that the bloodstream and respiratory isolates were clonally related. Although chest imaging showed no typical signs of bacterial pneumonia, a comprehensive evaluation found no evidence of MSSA infection in other potential sites, such as the urinary tract or skin and soft tissues. This supports the hypothesis that disruption of the alveolar-capillary barrier may have facilitated the translocation of respiratory tract bacteria into the bloodstream, leading to bacteremia. The respiratory tract is thus considered a potential source of infection. This case highlights the need to remain vigilant for bacteremia caused by pulmonary barrier disruption in immunosuppressed patients, even in the absence of classical imaging features of MSSA pneumonia, and underscores the potential value of genomic epidemiology in infection source tracing.</Abstract>
      <AbstractLanguage>English</AbstractLanguage>
      <Keywords>Methicillin Susceptible Staphylococcus Aureus,Systemic Lupus Erythematosus,Bacteremia,Immunosuppression</Keywords>
      <URLs>
        <Abstract>https://www.jmedicalcasereports.org/ubijournal-v1copy/journals/abstract.php?article_id=15888&amp;title=Respiratory Colonization or Infection? Unraveling The Origin of Methicillin-Sensitive Staphylococcus Aureus Bacteremia in An Immunosuppressed Patient with Systemic Lupus Erythematosus</Abstract>
      </URLs>
      <References>
        <ReferencesarticleTitle>References</ReferencesarticleTitle>
        <ReferencesfirstPage>16</ReferencesfirstPage>
        <ReferenceslastPage>19</ReferenceslastPage>
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      </References>
    </Journal>
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