{"id":10277,"date":"2022-01-28T11:26:49","date_gmt":"2022-01-28T09:26:49","guid":{"rendered":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/infectology\/fever-of-unknown-origin-fuo\/"},"modified":"2022-01-30T08:54:56","modified_gmt":"2022-01-30T06:54:56","slug":"fever-of-unknown-origin-fuo","status":"publish","type":"page","link":"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/infectology\/fever-of-unknown-origin-fuo\/","title":{"rendered":"Fever of unknown origin (FUO)"},"content":{"rendered":"\n

Introduction<\/h4>\n<\/span>\n\n\n

Fever of unknown origin (FUO) is clinically defined as a combination of fever<\/strong> (>38.3\u00b0C) lasting over three weeks<\/strong>, and without a diagnosed etiology despite one week of inpatient investigations<\/strong> (or three outpatient visits).<\/p>\n\n\n<\/span>\n

Classification<\/h4>\n<\/span>\n\n\n

The Durack and Street<\/strong> classification classifies FUO into four entities, with classical FUO being the traditional definition (mentioned above).<\/p>\n\n\n\n

  • Classical FUO <\/li>
  • Hospital-acquired FUO<\/li>
  • Immunocompromised or neutropenic FUO<\/li>
  • HIV-related FUO<\/li><\/ul>\n\n\n<\/span>\n

    Etiology<\/h4>\n<\/span>\n\n\n
    • Infections <\/strong>(most common)
      • Mycobacterial infections<\/li>
      • UTI<\/li>
      • Endocarditis<\/li>
      • EBV<\/li><\/ul>
        • Malaria<\/li><\/ul><\/li>
        • Malignancy <\/strong>(2nd most common)
          • Lymphomas (mostly HL)<\/li>
          • Leukemias<\/li>
          • RCC<\/li><\/ul><\/li>
          • Autoimmune<\/strong>
            • SLE<\/li>
            • Vasculitides<\/li>
            • Crohn disease<\/li>
            • Sercoidosis<\/li><\/ul><\/li>
            • Drug-induced<\/strong>
              • Sulfonamides<\/li>
              • Penicillin<\/li>
              • Quinidine<\/li>
              • Barbiturates<\/li><\/ul><\/li>
              • Everything else<\/strong>
                • DVT<\/li>
                • PE<\/li>
                • Hemolytic anemia<\/li><\/ul>
                  • Factitious fever<\/li><\/ul><\/li><\/ul>\n\n\n\n

                    Mnemonic: IMADE<\/strong><\/p>\n\n\n<\/span>\n

                    Diagnosis<\/h4>\n<\/span>\n\n\n
                    • In-depth medical history and physical examination<\/li>
                    • Labratory
                      • TBC<\/li>
                      • Urinalysis<\/li>
                      • Cultures (blood, urine, stool, throat, CSF)<\/li><\/ul>
                        • Serology (ANAs, ANCAs, RF)<\/li>
                        • Acute phase reactants (ESR, CRP, procalcitonin)<\/li>
                        • TSH<\/li><\/ul><\/li>
                        • Imaging
                          • CXR<\/li>
                          • Echocardiography<\/li>
                          • Chest and abdomen CT<\/li>
                          • MRI<\/li><\/ul><\/li>
                          • Biopsy of lymph nodes and bone marrow<\/li><\/ul>\n\n\n<\/span>\n

                            Treatment<\/h4>\n<\/span>\n\n\n
                            • Avoid antibiotics and antipyrretics unless clinically unstable, and continue the diagnosis and observation.<\/li>
                            • In unstable patients and neutropenic fever
                              • Emperic treatment using fluoroquinolone together with augmentin (amoxicillin+clavulanic acid)<\/li>
                              • In high-risk patients use cefepime or carbapenem as anti-pseudomonal treatment<\/li>
                              • In case of lack of response, consider vancomycin (MRSA), linezolid (VRSA), fluconazole (fungi)<\/li><\/ul><\/li><\/ul>\n<\/span>

                                Introduction<\/h4>

                                Classification<\/h4>

                                Etiology<\/h4>

                                Diagnosis<\/h4>

                                Treatment<\/h4><\/div>","protected":false},"excerpt":{"rendered":"

                                Introduction Fever of unknown origin (FUO) is clinically defined as a combination of fever (>38.3\u00b0C) lasting over three weeks, and without a diagnosed etiology despite one week of inpatient investigations (or three outpatient visits). Classification The Durack and Street classification classifies FUO into four entities, with classical FUO being the traditional definition (mentioned above). Classical […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":10247,"menu_order":3,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-10277","page","type-page","status-publish","hentry"],"yoast_head":"\nFever of unknown origin (FUO) – Meddists<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/meddists.com\/learn\/clinical\/internal-medicine\/infectology\/fever-of-unknown-origin-fuo\/\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" 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