Nosocomial Pneumonia

Front 1

Important factors when differentiating Pneumonia Categories include:

Back 1

Environment of patient when infection occurred (Hospital verses community; Intensive care unit versus general patient unit)

Time when infection occurs (Especially important for nosocomial infection)

Patient confounding factors
[Other important disease states (ex. HIV, cancer, etc)]

Front 2

what is the time frame/definition of HAP (hospital acquired pneumonia)?

Back 2

Pneumonia occurring 48 hours or more after admission, not incubating at time of admission

Front 3

what is the time frame/definition of ventilator-associated pneumonia (VAP)?

Back 3

Pneumonia that arises more that 48-72 hours after endotracheal intubation

Front 4

what is the time frame/definition of Health-care associated pneumonia (HCAP)?

Back 4

Includes patients:
-hospitalized within an acute care hospital for 2 plus days within 90 days of admission

-residing in nursing home or long-term care facility prior to admission

-who have received IV antibiotics, chemotherapy, or wound care with 30 days of admission

-who attend a hospital or hemodialysis clinic

Front 5

why is it important to differentiate place of infection?

Back 5

1. different microbiological pathogens

2. different therapy guidelines

Front 6

what is the difference btwn microbiological pathogens in community vs. hospital acquired pneumonia?

Back 6

Community: Streptococcus, atypical bacteria

Hospitals: more resistant gram negative pathogens; Staphyloccocus aureus

Front 7

what is the difference btwn therapy guidelines in community vs. hospital acquired pneumonia?

Back 7

Community: Streptococcus pneumoniae most important; less emphasis on gram-negative pathogens

Hospital: typically need to utilize more “big-gun” gram-negative antibiotics to deal with the possible pathogens seen

Front 8

how is early onset of hospital acquired pneumonia defined?

Back 8

Occurring within 4 days of hospitalization

Patients who have received prior abx or who have been hospitalized within past 90 days should be treated similar to late-onset patients (even if hospitalized <5 days)

Front 9

how is late onset of hospital acquired pneumonia defined?

Back 9

Occurring 5 or more days after hospitalization

Associated with increased presence of multi-drug resistant (MDR) pathogens

Associated with higher crude mortality

Front 10

what causes nosocomial pneumonia?

Back 10

Answer: Bacteria!!
Aerobic-gram-negative bacilli
Gram-positive cocci

Fungi and viruses are much less common pathogens

Front 11

3 Factors associated with increased mortality associated with nosocomial pneumo?

Back 11

Bacteremia, especially with Pseudomonas aeruginosa or Acinetobacter species

Medical rather than surgical illness

Treatment with ineffective or delayed antibiotic therapy!

Front 12

non-MDR pathogens associated with nosocomial pneumo?

Back 12

Streptococcus pneumoniae

Haemophilus influenzae

Methicillin-sensitive Staphylococcus aureus

Antibiotic-sensitive enteric gram-negative bacilli
-Escherichia coli
-Klebsiella pneumoniae
-Enterobacter species
-Proteus species
-Serratia marcescens

Front 13

MDR pathogens associated with nosocomial pneump

Back 13

Gram-negatives:
Pseudomonas aeruginosa
Extended spectrum B-lactamase producing gram negative rods (Klebsiella, Ecoli, Enterobacter, Serratia
Acinetobacter species)

Gram-positive
Methicillin-resistant Staphyloccus aureus (MRSA)

Other:
Legionella pneumophila

Front 14

Risk factors for MDR pathogens:

Back 14

JUST KNOW HOSPTALIZATION OF 5 DAYS or more*** (everything else is FYI)

Antimicrobial therapy in preceding 90 days

Current hospitalization of *5 days* or more

High frequency of antibiotic resistance in the community or in the specific hospital unit

Presence of risk factors or HCAP:
Hospitalization for 2 days or more in the preceding 90 days,
Residence in a nursing home or extended care facility,
Home infusion therapy (including antibiotics),
Chronic dialysis within 30 days,
Home wound care,
Family member with multidrug-resistant pathogen,

Immunosuppressive disease and/or therapy

Front 15

what is the most common MDR gram-negative bacterial pathogen?

It is also:

Very virulent organism (high mortality risk)

Highly resistant
(Intrinsic resistance to many antimicrobials,
Capacity to develop resistance to all known classes of antibiotics,
Resistance rates increasing within the U.S.)

Back 15

pseudomonas aeruginosa

Front 16

List the antibiotics that generally cover Pseudomonas aeruginosa

Back 16

Piperacillin/tazobactam
Ticarcillin/clavulanate
Ceftazidime
Cefepime
Meropenem
Imipenem-cilastatin
Ciprofloxacin*
Levofloxacin (750mg)*
Tobramycin
Gentamicin
Amikacin
Aztreonam

Front 17

is Acinetobacter an MDR or a non-MDR? what are the most effective ab's against it?

Back 17

Inherent resistance to many classes of antibiotics
(Increasing resistance seen in the U.S.)

Generally less virulent in comparison to Pseudomonas aeruginosa

Most consistently effective antibiotics include:
-Carbapenems
-Ampicillin-sulbactam
-The polymyxins (colistin)

Front 18

Extended-spectrum B-lactamase-producing Enterobacteriaceae (ESBL’s) typically include what pathogens?

Back 18

Klebsiella, E.coli, Enterobacter, and Serratia species

Front 19

most reliable treatment choice for extended-spectrum B-lactamase-producing Enterobacteriaceae (ESBL’s)is:

Back 19

carbepenems

(ESBL's are typically resistant to most abs)

Front 20

what are some therapy options for Methicillin-Resistant Staphylococcus aureus (MRSA)?

Back 20

Vancomycin
Aggressive dosing recommended;
Keep trough level between 15-20 mcg/mL

Linezolid
Data exist suggesting mortality benefit for MRSA pneumonia

Front 21

what is one of the most important things to do when diagnosing a nosocomial infection???

Back 21

get a lower respiratory tract culture before antibiotics started or changed (1. endotracheal aspirate 2. bronchoalveolar lavage 3. potected specimen brush)

Front 22

what is the main difference on x-rays btwn nosocomial vs. community acquired pneumo

Back 22

w/nosocomial –usually bilateral (on both sides) b/c people are usually laying in bed when they acquire it

Front 23

1. suspect HAP, VAP, or HCAP
2. obtain lower respiratory tract sample for culture and microscopy
3. what next?

Back 23

being empiric treatment!!!!!!

(unless there is both a low clinical suspicion for pneumo and negative microscopy or LRT sample)

Front 24

general treatment principles w/nosocomial pneumo

Back 24

Early antibiotics therapy key

Broad spectrum up front

COMBINATION therapy should be utilized for patients at risk for MDR pathogens
...If aminoglycoside used, may be stopped after 5-7 days
May utilize monotherapy once cultures available

If on previous antibiotics (within 2 weeks), should try to utilize different antibiotic class due to resistance risk

Front 25

should initial therapy for nosocomial infections be PO or IV?

Back 25

IV

- switch to PO therapy with good clinical response; depends on bioavailability of agents

Front 26

when should LONGER therapy be used?

Back 26

if pathogen is Pseudomonas or Acinetobacter

Front 27

specific treatment for NON-MDR pathogens:

Back 27

Ceftriaxone ; cefotaxime
Levofloxacin, moxifloxacin, or (ciprofloxacin* -- not recommended)
Ampicillin/sulbactam
Ertapenem

Front 28

treatment for MDR pathogens

Back 28

minimum of 1 antibiotic from each of 3 classes:


Group 1:
Antipseudomonal cephalosporin (cefepime, ceftazidime)
Antipseudomonal carbapenem (imipenem, meropenem)
b-Lactam/b-lactamase inhibitor (piperacillin-tazobactam)
AND
Group 2:
Antipseudomonal fluoroquinolone (ciprofloxacin, levofloxacin) or aminoglycosides (genta, tobra, amik)
AND
Group 3: (directed towards MRSA)
Vancomycin, linezolid

Front 29

how should aminoglycosides be dosed? why?

Back 29

QD

improved PK/PD, improved safety (kidney, oto-toxicity risk decr)

higher peak concentrations, longer period of time w/o drug exposure to kidney

takes advantage of post=antibiotic effect

Front 30

why use combination therapy?

Back 30

Provide broad-spectrum empiric coverage of MOST possible pathogens


Less important reasons:
Antibiotic synergy
Decrease risk for resistance emergence

Front 31

when should combination therapy be used?

Back 31

Use in patients at risk for MDR pathogens

Monotherapy is adequate otherwise

Front 32

rules for combination therapy

Back 32

For high risk patients, use combination therapy up front and then scale back based upon culture results


Not just any combination is o.k.

Use separate classes utilizing different mechanisms of action
b-lactam + aminoglycoside
b-lactam + fluoroquinolone

Front 33

duration of therapy

Back 33

Most antibiotic killing and clinical improvements occur in the 1st 6 days of therapy

In patients given initial appropriate antibiotic therapy:
Make effort to shorten duration from 14 to 21 days to periods as short as 7 days
If pathogen is Pseudomonas aeruginosa or Acinetobacter species, longer therapy (14 days+) duration still advised

Front 34

Consequences of prolonged therapy include:

Back 34

Colonization with new, more resistant bacteria
Risk for recurrent pneumonia with these bugs

Front 35

response to therapy? when is it seen?

Back 35

Clinical improvement typically takes at least 48 hour to see

Unless there is a rapid clinical decline, continue therapy without alteration until day 3 at least

Day 3 and beyond:
Responding patient
Continue therapy and consider de-escalation
Non-responding patient
Broaden coverage if possible
Consider other diagnosis