31 Treatment of Infections in the Immunocompromised Host Flashcards
Currently, a little more than half of all documented infections in neutropenic patients are caused by ___________pathogens.
Gram-positive pathogens
This change likely resulted from the popularity of semipermanent venous catheters and from the use of prophylactic regimens that are active against gram-negative rods.
Of gram-positive pathogens, ________________are the most common
Coagulase-negative staphylococci
Bacteria increasing in frequency among neutropenic patients, especially in those receiving hematopoietic stem cell transplant, likely because of their higher incidence of mucositis.
Enterococcus and viridans group streptococci
Organism that are less common unless periodontal or gastrointestinal pathology coexists where they tend to be part of a polymicrobial process.
Anaerobic
Bacterial infections common among patients with Hodgkin lymphoma, other lymphomas, or chronic lymphocytic leukemia primarily suffer from impaired cell-mediated immunity and diminished antibody production
Encapsulated organisms such as Pneumococcus or Haemophilus, Listeria and Nocardia infections
Most frequently isolated fungal pathogen
Candida species
Serves as a reservoir for Candida, with infection resulting from translocation across damaged intestinal epithelium or broad-spectrum antibiotics.
Gastrointestinal tract
Infections caused by angio-invasive molds
Aspergillus and mucormycosis
Endemic to the southwestern United States, in particular Arizona and the San Joaquin Valley in California.
Coccidioides
Endemic in the Ohio and Mississippi River Valleys
Histoplasma
A ubiquitous, endogenous fungus that may cause pneumonia in neutropenic patients and in those with defective cellmediated immunity.
Pneumocystis jiroveci
Virus-associated hemorrhagic cystitis caused by___________ common among hematopoietic stem cell transplant recipients.
BK virus and adenovirus i
Blood cultures should be done before initiation of antibiotic therapy, and periodically thereafter if fever persists.
Ideally, _____ sets of blood samples should be drawn, especially for the initial episode of fever.
Two sets of blood samples
Current recommendations as initial empiric therapy for bacterial infections
Single-drug therapy with an antipseudomonal β-lactam
Piperacillin-tazobactam, imipenem, meropenem, cefepime, and ceftazidime
TRUE OR FALSE
Empiric gram-positive coverage is not routinely recommended among patients with febrile neutropenia but should be considered under certain circumstances
TRUE
Empiric gram-positive coverage is not routinely recommended among patients with febrile neutropenia but should be considered under certain circumstances
Indications for empiric gram-positive coverage
Patients with evidence of central line infection, skin and soft tissue infection, or bacterial pneumonia, or who have a recent history of methicillin-resistant Staphylococcus aureus (MRSA) infection
Patients with hemodynamic compromise and/or critical illness caused by suspected infection
Staphylococcus aureus (MRSA) infection are at increased risk for MRSA infection and should be started on empiric ____________.
Vancomycin
TRUE OR FALSE
Having an indwelling catheter without evidence of infection is an indication for gram-positive coverage.
FALSE
Having an indwelling catheter without evidence of infection is not an indication for gram-positive coverage.
Among patients who are unstable or in whom antibiotic resistance is suspected, it is reasonable to add a second gram-negative antibiotic like
Aminoglycosides
Fluoroquinolones
First-line agents for severe MRSA infections
Vancomycin, linezolid, and daptomycin
A commonly used alternative to vancomycin but causes thrombocytopenia
Linezolid
A good alternative to vancomycin for bloodstream infections but should not be used for pneumonia because of inactivation by surfactant.
Daptomycin
Agents for vancomycin-resistant Enterococcus (VRE)
Linezolid and daptomycin
Quinupristin/dalfopristin**
**not active against Enterococcus faecalis and is further limited by its toxicity profile
First-line therapy for ESBL producing gram-negative bacteria
Carbapenems (imipenem, meropenem, ertapenem)
When is empiric antifungal therapy should be considered in febrile patients
If empiric antibiotic therapy is not effective within 5 to 7 days.
Preparation of Amphotericin that is less nephrotoxic
AmBisome (liposomal amphotericin B)
The first-line treatment for mucormycosis
Liposomal amphotericin
Approved for treatment of C albicans, Cryptococcus neoformans, and Coccidioides immitis
Fluconazole
It is less active against non-albicans Candida species and is completely inactive against Candida krusei.
It also lacks activity against Aspergillus.
The first-line therapy against Aspergillus
Voriconazole
Side effects of voriconazole
Visual abnormalities, hallucinations, and liver function test (LFT) abnormalities
Has shown promise as salvage therapy for both invasive aspergillosis and mucormycosis
Posaconazole
Unlike the other azoles (which cause QT prolongation), this azole actually causes QT shortening
Isavuconazole
First-line agents for invasive Candida infections
Echinocandins
Caspofungin, micafungin, and anidulafungin
Approved for first-line empirical use in febrile neutropenia or as salvage therapy for aspergillosis
Caspofungin
Treatment for Pneumocystis jiroveci pneumonia (PCP)
High-dose trimethoprim-sulfamethoxazole
Option for patients who are allergic to or otherwise intolerant of trimethoprim-sulfamethoxazole
Primaquine-clindamycin
Active against HSV and, at higher doses, against VZV
Acyclovir
Effective in treating herpes simplex and zoster infections and may be administered less frequently but are not available for intravenous administration
Famciclovir and valacyclovir
Effective in treatment of CMV disease and are also active against herpes simplex
Ganciclovir, valganciclovir, and foscarnet
Usually the first-line therapy against CMV but results in marrow suppression
Ganciclovir or valganciclovir
Used to treat RSV pneumonia in immunocompromised patients
Ribavirin plus an adjunctive immunomodulator such as intravenous immunoglobulin
Used if influenza A virus is suspected
Oseltamivir or zanamivir
First-line therapy for tuberculosis
Rifampin, isoniazid, pyrazinamide, and ethambutol
Treatment for Mycobacterium avium-intracellulare complex
Clarithromycin, rifabutin, and ethambutol
Suggested duration of antimicrobials
US: Continue antibiotics until fever resolution and bone marrow recovery (ANC ≥0.5 × 109/L)
Europe: returning to a prophylactic regimen in select patients before the ANC reaches ≥0.5 × 109/L
Type of infection with elevated serum alkaline phosphatase levels and the presence of multiple “bull’s eye” or “target” lesions in the liver on CT
Hepatosplenic candidiasis
Treatment for immune reconstitution inflammatory syndrome
Glucocorticoids
Most commonly isolated organism in indwelling catheter infections
Coagulase-negative Staphylococcus spp.
If the catheter is to be retained, a ______-day course of antibiotics is recommended and antibiotic lock therapy should be strongly considered if feasible.
10- to 14-day
TRUE OR FALSE
Gram-negative, S aureus, and fungal infections of the catheter usually does not necessitate its removal.
FALSE
Gram-negative, S aureus, and fungal infections of the catheter usually necessitate its removal.
Antibiotic therapy for at least 14 days is recommended.
Risk stratification scores for outpatient therapy
- Multinational Association of Supportive Care in Cancer (MASCC) index
- Talcott’s rules
- Clinical Index of Stable Febrile Neutropenia (CISNE) mode
Current recommended outpatient antibiotic regimens
Fluoroquinolone (ciprofloxacin or levofloxacin) combined with amoxicillin-clavulanate or clindamycin (if the patient is penicillin-allergic)
Fluoroquinolones that has more activity against Pseudomonas
Ciprofloxacin
Fluoroquinolones that is more active against gram-positive organisms including viridans streptococci that are commonly involved in mucositis.
Levofloxacin
Effective at preventing recurrent herpes simplex infections in patients receiving chemotherapy
Acyclovir , valacyclovir
Recommended as postexposure varicella prophylaxis for high-risk, nonimmune patients
VZV immunoglobulin
A new antiviral with a mechanism of action distinct from ganciclovir; importantly, it does not cause myelosuppression
Letermovir
TRUE OR FALSE
Immunizations with killed vaccines such as influenza are recommended. Live-attenuated vaccines, such as measles, should be avoided during immunosuppression.
TRUE
Immunizations with killed vaccines such as influenza are recommended. Live-attenuated vaccines, such as measles, should be avoided during immunosuppression.
