Neutropenic Fever Flashcards
Neutropenic fever arises in cancer pts taking chemotherapeutrics that induce _____ and reduce the developmental integrity of the _______
Myelosuppression; GI mucosa
[myelosuppression can lead to a muted and blunted neutrophil-mediated inflammatory response, therefore a fever is the earliest (and maybe the only) sign of infection]
Define neutropenic fever
Temp above 38.5 C (101.4 F) with an absolute neutrophil count (ANC) below 500 cells/microliter
Neutropenic fever constitutes a medical emergency with a 100% mortality rate if not treated for 3 days. 99% of the infectious agents involved with neutropenic fever are normal, endogenous flora. What are some of the most common infectious agents associated with indwelling central venous catheters?
S.aureus
S.epidermidis
Klebsiella spp.
What are some of the fungal infections associated with neutropenic fever?
Candida (most common)
Aspergillus and other fungi may be involved
Pneumocystis and toxoplasma can cause fever but are relatively unusual
What type of physical exam should be avoided if the ANC is <500 cells/microliter
Rectal exam
Microscopic tears occur during rectal exams, allowing a potal for bacteria to enter the body — potentially leads to fulminant sepsis and death w/i 24 hours
[also consider avoiding gynecologic exam in females]
Primary prophylaxis involves administration of antimicrobial drugs to prevent infection in pts at increased risk. What defines a pt as high risk?
Those who are expected to be neutropenic (<500 cells/microliter) for > 7 days
Antibiotics used for primary prophylaxis in high risk pts target P.aeruginosa and other gram negative bacilli. What class is typically used?
Fluoroquinolones — levofloxacin, ciprofloxacin
Cautions with fluoroquinolone use
Prolonged QT interval
Tendon rupture
Promotion of abx resistance
Increased risk for C.diff
What antifungal is used for primary prophylaxis in high risk pts and why?
Fluconazole — primarily targets candida
Advantages to fluconazole — oral and IV formulations, good tolerability, inexpensive generic, less drug-drug interactions vs. other extended spectrum azoles
Cautions to fluconazole use
Narrower spectrum for candida spp.
Fluconazole resistance
No activity against Aspergillus spp.
While fluconazole is the antifungal of choice for primary prophylaxis, what alternative drug class may be used d/t its broader spectrum of coverage and good safety profile?
Echinocandins — caspofungin, micafungin, anidulafungin
[cautions = IV only, higher cost]
Secondary prophylaxis is utilized to prevent recurrent infection, usually in pts with hx of prior fungal infection. What drug is given in this case?
Voriconazole
Voriconazole is a first-line agent for _______
It cannot be given together with certain chemotherapeutics like _____ or ______. Severe neurotoxicity occurs if Voriconazole is given with chemotherapeutic ________.
Aspergillus spp.
Cytarabine; fludarabine; vincristine
Since voriconazole cannot be given together with some chemotherapeutics, one strategy is to suspend it 1 week prior to chemotherapy and to start it again after the dosing regimen.
To continue an antifungal during chemotherapy, _______ or an _______ can be used
Amphotericin B; echinocandin
Empiric therapy is utilized when a suspected neutropenic fever is occurring. What is the general management strategy in this case?
IV abx given until ANC is above 1000 cells/mL
After this is achieved, a switch to oral abx is possible (ONLY if pt is afebrile and tolerating meals w/o emesis)
Combination IV regimens are preferred to single agents