31 Treatment of Infections in the Immunocompromised Host

Question 1

Currently, a little more than half of all documented infections in neutropenic patients are caused by ___________pathogens.

Answer 1

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.

Question 2

Of gram-positive pathogens, ________________are the most common

Answer 2

Coagulase-negative staphylococci

Question 3

Bacteria increasing in frequency among neutropenic patients, especially in those receiving hematopoietic stem cell transplant, likely because of their higher incidence of mucositis.

Answer 3

Enterococcus and viridans group streptococci

Question 4

Organism that are less common unless periodontal or gastrointestinal pathology coexists where they tend to be part of a polymicrobial process.

Answer 4

Anaerobic

Question 5

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

Answer 5

Encapsulated organisms such as Pneumococcus or Haemophilus, Listeria and Nocardia infections

Question 6

Most frequently isolated fungal pathogen

Answer 6

Candida species

Question 7

Serves as a reservoir for Candida, with infection resulting from translocation across damaged intestinal epithelium or broad-spectrum antibiotics.

Answer 7

Gastrointestinal tract

Question 8

Infections caused by angio-invasive molds

Answer 8

Aspergillus and mucormycosis

Question 9

Endemic to the southwestern United States, in particular Arizona and the San Joaquin Valley in California.

Answer 9

Coccidioides

Question 10

Endemic in the Ohio and Mississippi River Valleys

Answer 10

Histoplasma

Question 11

A ubiquitous, endogenous fungus that may cause pneumonia in neutropenic patients and in those with defective cellmediated immunity.

Answer 11

Pneumocystis jiroveci

Question 12

Virus-associated hemorrhagic cystitis caused by___________ common among hematopoietic stem cell transplant recipients.

Answer 12

BK virus and adenovirus i

Question 13

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.

Answer 13

Two sets of blood samples

Question 14

Current recommendations as initial empiric therapy for bacterial infections

Answer 14

Single-drug therapy with an antipseudomonal β-lactam

Piperacillin-tazobactam, imipenem, meropenem, cefepime, and ceftazidime

Question 15

TRUE OR FALSE

Empiric gram-positive coverage is not routinely recommended among patients with febrile neutropenia but should be considered under certain circumstances

Answer 15

TRUE

Empiric gram-positive coverage is not routinely recommended among patients with febrile neutropenia but should be considered under certain circumstances

Question 16

Indications for empiric gram-positive coverage

Answer 16

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

Question 17

Staphylococcus aureus (MRSA) infection are at increased risk for MRSA infection and should be started on empiric ____________.

Answer 17

Vancomycin

Question 18

TRUE OR FALSE

Having an indwelling catheter without evidence of infection is an indication for gram-positive coverage.

Answer 18

FALSE

Having an indwelling catheter without evidence of infection is not an indication for gram-positive coverage.

Question 19

Among patients who are unstable or in whom antibiotic resistance is suspected, it is reasonable to add a second gram-negative antibiotic like

Answer 19

Aminoglycosides

Fluoroquinolones

Question 20

First-line agents for severe MRSA infections

Answer 20

Vancomycin, linezolid, and daptomycin

Question 21

A commonly used alternative to vancomycin but causes thrombocytopenia

Answer 21

Linezolid

Question 22

A good alternative to vancomycin for bloodstream infections but should not be used for pneumonia because of inactivation by surfactant.

Answer 22

Daptomycin

Question 23

Agents for vancomycin-resistant Enterococcus (VRE)

Answer 23

Linezolid and daptomycin

Quinupristin/dalfopristin**

**not active against Enterococcus faecalis and is further limited by its toxicity profile

Question 24

First-line therapy for ESBL producing gram-negative bacteria

Answer 24

Carbapenems (imipenem, meropenem, ertapenem)

Question 25

When is empiric antifungal therapy should be considered in febrile patients

Answer 25

If empiric antibiotic therapy is not effective within 5 to 7 days.

Question 26

Preparation of Amphotericin that is less nephrotoxic

Answer 26

AmBisome (liposomal amphotericin B)

Question 27

The first-line treatment for mucormycosis

Answer 27

Liposomal amphotericin

Question 28

Approved for treatment of C albicans, Cryptococcus neoformans, and Coccidioides immitis

Answer 28

Fluconazole

It is less active against non-albicans Candida species and is completely inactive against Candida krusei.
It also lacks activity against Aspergillus.

Question 29

The first-line therapy against Aspergillus

Answer 29

Voriconazole

Question 30

Side effects of voriconazole

Answer 30

Visual abnormalities, hallucinations, and liver function test (LFT) abnormalities

Question 31

Has shown promise as salvage therapy for both invasive aspergillosis and mucormycosis

Answer 31

Posaconazole

Question 32

Unlike the other azoles (which cause QT prolongation), this azole actually causes QT shortening

Answer 32

Isavuconazole

Question 33

First-line agents for invasive Candida infections

Answer 33

Echinocandins

Caspofungin, micafungin, and anidulafungin

Question 34

Approved for first-line empirical use in febrile neutropenia or as salvage therapy for aspergillosis

Answer 34

Caspofungin

Question 35

Treatment for Pneumocystis jiroveci pneumonia (PCP)

Answer 35

High-dose trimethoprim-sulfamethoxazole

Question 36

Option for patients who are allergic to or otherwise intolerant of trimethoprim-sulfamethoxazole

Answer 36

Primaquine-clindamycin

Question 37

Active against HSV and, at higher doses, against VZV

Answer 37

Acyclovir

Question 38

Effective in treating herpes simplex and zoster infections and may be administered less frequently but are not available for intravenous administration

Answer 38

Famciclovir and valacyclovir

Question 39

Effective in treatment of CMV disease and are also active against herpes simplex

Answer 39

Ganciclovir, valganciclovir, and foscarnet

Question 40

Usually the first-line therapy against CMV but results in marrow suppression

Answer 40

Ganciclovir or valganciclovir

Question 41

Used to treat RSV pneumonia in immunocompromised patients

Answer 41

Ribavirin plus an adjunctive immunomodulator such as intravenous immunoglobulin

Question 42

Used if influenza A virus is suspected

Answer 42

Oseltamivir or zanamivir

Question 43

First-line therapy for tuberculosis

Answer 43

Rifampin, isoniazid, pyrazinamide, and ethambutol

Question 44

Treatment for Mycobacterium avium-intracellulare complex

Answer 44

Clarithromycin, rifabutin, and ethambutol

Question 45

Suggested duration of antimicrobials

Answer 45

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

Question 46

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

Answer 46

Hepatosplenic candidiasis

Question 47

Treatment for immune reconstitution inflammatory syndrome

Answer 47

Glucocorticoids

Question 48

Most commonly isolated organism in indwelling catheter infections

Answer 48

Coagulase-negative Staphylococcus spp.

Question 49

If the catheter is to be retained, a ______-day course of antibiotics is recommended and antibiotic lock therapy should be strongly considered if feasible.

Answer 49

10- to 14-day

Question 50

TRUE OR FALSE

Gram-negative, S aureus, and fungal infections of the catheter usually does not necessitate its removal.

Answer 50

FALSE

Gram-negative, S aureus, and fungal infections of the catheter usually necessitate its removal.

Antibiotic therapy for at least 14 days is recommended.

Question 51

Risk stratification scores for outpatient therapy

Answer 51

• Multinational Association of Supportive Care in Cancer (MASCC) index
• Talcott’s rules
• Clinical Index of Stable Febrile Neutropenia (CISNE) mode

Question 52

Current recommended outpatient antibiotic regimens

Answer 52

Fluoroquinolone (ciprofloxacin or levofloxacin) combined with amoxicillin-clavulanate or clindamycin (if the patient is penicillin-allergic)

Question 53

Fluoroquinolones that has more activity against Pseudomonas

Answer 53

Ciprofloxacin

Question 54

Fluoroquinolones that is more active against gram-positive organisms including viridans streptococci that are commonly involved in mucositis.

Answer 54

Levofloxacin

Question 55

Effective at preventing recurrent herpes simplex infections in patients receiving chemotherapy

Answer 55

Acyclovir , valacyclovir

Question 56

Recommended as postexposure varicella prophylaxis for high-risk, nonimmune patients

Answer 56

VZV immunoglobulin

Question 57

A new antiviral with a mechanism of action distinct from ganciclovir; importantly, it does not cause myelosuppression

Answer 57

Letermovir

Question 58

TRUE OR FALSE

Immunizations with killed vaccines such as influenza are recommended. Live-attenuated vaccines, such as measles, should be avoided during immunosuppression.

Answer 58

TRUE

Immunizations with killed vaccines such as influenza are recommended. Live-attenuated vaccines, such as measles, should be avoided during immunosuppression.