This handout is for fever of unknown origin (fuo). Your care team identified this based on: classic fuo — fever >38.3°c ≥3 wk + diagnostic uncertainty after 3 outpatient visits or 1 wk inpatient (petersdorf 1961 pmid 31271266; durack-street 1991 pmid 1651090).
Other reasons your team may use this plan: nosocomial fuo — hospitalized ≥24 h, fever onset post-admission, no infection on admission (durack-street 1991 pmid 1651090 — dvt/pe, drug fever, c diff, line/surgical site); neutropenic fuo — anc <500 + fever (idsa 2010 pmid 21205990; asco/idsa 2018 pmid 29461916 — emergent empiric within 1 h); hiv-associated fuo — cd4-stratified opportunistic infection / iris / lymphoma differential (durack-street 1991 pmid 1651090).
Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.
| Medication | Starting dose | How | When | What it does |
|---|---|---|---|---|
| cefepime | 2 g IV | IV | q8h (renal-dose adjusted) | IDSA 2010 PMID 21205990 + ASCO/IDSA 2018 PMID 29461916 — first-line antipseudomonal monotherapy for neutropenic fever; within 1 h of presentation |
| vancomycin | 15-20 mg/kg IV | IV | q8-12h, target AUC 400-600 | IDSA 2010 — add for empiric MRSA / coag-negative staph in unstable / line-associated / soft tissue |
| ceftriaxone | 2 g IV | IV | BID for endocarditis empiric | AHA 2023 infective endocarditis empiric pending culture; obtain ≥3 cultures FIRST |
| prednisone | 1 mg/kg PO (typically 60 mg) | PO | daily | Do NOT delay vision-saving steroid in arteritis; biopsy still positive within 7-14 d (Mulders-Manders ESCMID 2019 PMID 31271266) |
| micafungin | 100 mg IV | IV | daily | IDSA 2010 PMID 21205990 + ASCO/IDSA 2018 PMID 29461916 — empiric antifungal for persistent neutropenic fever ≥4 d on broad-spectrum antibiotics |
Plan: Empiric coverage axis — restricted to neutropenic fever, suspected unstable endocarditis, strong GCA (IDSA 2010 PMID 21205990; ASCO/IDSA 2018 PMID 29461916; AHA 2023; ESCMID 2019 PMID 31271266)
Contact your care team if any of the following happen:
Call 911 or go to the nearest emergency room right away if you have:
Repeat workup if undiagnosed; ~20% self-resolve without diagnosis; specialty referrals (rheum, oncology, ID); 4-wk reassessment if undiagnosed
Guideline: Petersdorf NEJM 1961 (PMID 31271266) + Durack-Street 1991 modern classification + Mulders-Manders ESCMID 2019 Diagnostics (PMID 31271266) + Ergul PET-CT FUO 2014 (PMID 29567271) + Bleeker-Rovers PET-CT FUO 2007 (PMID 17220753) + IDSA Neutropenic Fever 2010 (PMID 21205990) + ASCO/IDSA Neutropenic 2018 (PMID 29461916) + Yamaguchi AOSD 1992 (PMID 1578458) + Wright NEJM FUO 2022