Transcript pneumonia
Community-Acquired Pneumonia (CAP)
Introduction
Pneumonia is the 6th leading cause of
death in the U.S.
90% of the deaths occur in persons over
65 years of age.
The etiology is 50% idiopathic
Only 20% with specific organism in
clinical practice
Introduction
According to the National Institutes of Health:
“at any given time, the noses and throats of
up to 70% of healthy people contain
pneumococcus” (the most common cause of
bacterial pneumonia).
The paradigm for any type of pneumonia is
the balance between the patient's host
defenses, the virulence of the potential
pathogen, and the size of the exposure to
the pathogen.
Definition
Pneumonia defined as inflammation of the
lung parenchyma; pneumonia is
characterized by consolidation of the
affected part and a filling of the alveolar air
spaces with exudate, inflammatory cells, and
fibrin.
Classification and categorization of
bacterial pneumonia
Anatomic/radiographic patterns of pneumonia
Lobar pneumonia
Bronchopneumonia
Interstitial pneumonia
Setting of infection
Community-acquired pneumonia CAP
Health care–associated pneumonia HCAP
Nursing home–associated pneumonia NHAP
Hospital-acquired pneumonia HAP
Ventilator-associated pneumonia VAP
Aspiration pneumonia
Pneumonia types
The 2005 ATS/IDSA guidelines distinguish the following types of
pneumonia:
Community-acquired pneumonia (CAP) is defined as an
acute infection of the pulmonary parenchyma in a patient who
has acquired the infection in the community.
Hospital-acquired (or nosocomial) pneumonia (HAP) is
pneumonia that occurs 48 hours or more after admission and
did not appear to be incubating at the time of admission .
Ventilator-associated pneumonia (VAP) is a type of HAP
that develops more than 48 to 72 hours after endotracheal
intubation .
Pneumonia types
Healthcare-associated pneumonia (HCAP) is defined as
pneumonia that occurs in a non-hospitalized patient with extensive
healthcare contact, as defined by one or more of the following :
-
Intravenous therapy, wound care, or intravenous chemotherapy
within the prior 30 days
-
Residence in a nursing home or other long-term care facility
-
Hospitalization in an acute care hospital for two or more days
within the prior 90 days
-
Attendance at a hospital or hemodialysis clinic within the prior
30 days
Bacterial pathogens of
pneumonia
Atypical organisms:
Gram-positive bacteria:
Gram-negative bacteria:
Anaerobic organisms:
Mycoplasma pneumonia,
Chlamydophila species (Chlamydophila psittaci, Chlamydophila
pneumoniae) Legionella species,Coxiella burnetii , Bordetella pertussis
S pneumoniae , S aureus
,Enterococcus (Enterococcus faecalis, Enterococcus faecium)
Actinomyces israelii ,Nocardia asteroides
Pseudomonas aeruginosa
Klebsiella pneumoniae Haemophilus influenzae Escherichia coli
Moraxella catarrhalis, Acinetobacter baumannii, Francisella
tularensis ,Bacillus anthracis ,Yersinia pestis
Klebsiella, Peptostreptococcus,
Bacteroides, Fusobacterium, and Prevotella
Frequency
The most common etiologies of community-acquired pneumonia (CAP), listed in descending
order of frequency are as follows :
Outpatient
Respiratory viruses
Inpatient, non-ICU
S pneumoniae
M pneumoniae
H influenzae
C pneumoniae
S pneumoniae
M pneumoniae
C pneumoniae
H influenzae
Legionella species
Aspiration
Respiratory viruses
Inpatient, ICU
S pneumoniae
S aureus
Legionella species
Gram-negative bacilli
Mortality/Morbidity
The average length of hospital stay for
a patient diagnosed with pneumonia
was 5 days
Pneumonia and influenza together were
the sixth-eighth leading cause of death
in the developed countries
History / Symptoms
Chest pain, dyspnea, hemoptysis (when
clearly delineated from hematemesis),
decreased exercise tolerance, and abdominal
pain from pleuritis are also highly indicative of
a pulmonary process
Rust-colored sputum - Frequently associated
with infection by S pneumoniae
Currant-jelly sputum - Frequently associated
with infection by Klebsiella species
Foul-smelling or bad-tasting sputum - Often
produced by anaerobic infections
History / Symptoms
Nonspecific symptoms such as rigors or
shaking chills, and malaise are
common.
Other nonspecific symptoms that may
be seen with pneumonia include
myalgias, headache, nausea, vomiting,
diarrhea, and altered sensorium
Aspiration risks
Patients at increased risk of aspiration with:
Alcoholism
Altered mental status
Anatomic abnormalities, congenital or
acquired
Dysphagia
GERD
Seizure disorder
Physical examination
Approximately 80 % are febrile - frequently
absent in older patients
A respiratory rate above 24 breaths/minute is
noted in 45 to 70 % of patients
Most sensitive sign in elderly patients
Tachycardia is common
Pneumonia Approach
The following 3 aspects of disease are important in the
management of pneumonia, in which diagnostic testing can play
a pivotal role:
Determining the presence of pneumonia
Assessing disease severity at the time of presentation
Identifying the causative agent
Differentiation between community-acquired
pneumonia (CAP), health care–associated pneumonia
(HCAP), hospital-acquired pneumonia (HAP), and other
pulmonary pathology
Diagnosis
Critical microbes — Some microbes are critical to
detect because they represent important
epidemiologic challenges and/or serious conditions
that require treatment different from standard
empiric regimens. These organisms include:
Legionella species
Influenza A and B
Community-associated methicillin-resistant
Staphylococcus aureus MRSA
Diagnosis
The incidence of S. aureus in the HCAP and HAP
groups were comparable (47 %) and significantly
higher than in the CAP group (26 %).
The rate of MRSA infection was also higher in
HCAP and HAP patients compared to CAP (27 and
23 versus 9 % for CAP).
MDR MultiDrudResistant)pathogens
Host risk factors for infection with MDR
pathogens include:
Receipt of antibiotics within the preceding 90
days
Current hospitalization of ≥5 days
High frequency of antibiotic resistance in the
community or in the specific hospital unit
Immunosuppressive disease and/or therapy
Presence of risk factors for HCAP
Laboratory studies
Diagnostic testing in patients with suspected pneumonia is driven mostly by the
possibility that the results would significantly alter empiric therapy and
management decisions and whether the test is likely to have a high yield.
The following initial tests are indicated with suspected pneumonia:
Blood culture, prior to antibiotic therapy
Sputum Gram stain and culture, prior to antibiotic therapy (if a goodquality, contaminant-sparse specimen containing <10 squamous
epithelial cells per low-power field can be obtained)
Sputum, serum, and/or urinary antigen test for Streptococcus
pneumoniae
Sputum and/or urinary antigen test for Legionella pneumophila
Endotracheal aspirate for culture in intubated patients
Culture and study of pleural fluid if effusion present
Immune serologies for Mycoplasma pneumoniae, Chlamydophila
pneumoniae, L pneumophila, and Coxiella burnetii - Results usually
not available until several weeks after infection
Severity of Pneumonia
Various systems to assess the severity of
disease and risk of death exist and are in
wide use, including :
PSI/PORT (ie, Pneumonia Severity
Index/Patient Outcomes Research Team
score)
CURB-65 system (ie, confusion, urea of 7
mmol/L, respiratory rate of 30 breaths/min,
and low systolic [90 mm Hg] or diastolic [60
mm Hg] blood pressure)
Imaging Studies
Lobar pneumonias
S pneumoniae: homogenous parenchymal lobar opacities with air bronchograms;
round opacity stimulating a pulmonary mass, called round pneumonia.
K pneumoniae: lobar expansion with bulging of interlobular fissures as well as
cavitations.
L pneumophila: Radiologic resolution tends to lag far behind clinical improvement (8
wk to clear).
Bronchopneumonias
S aureus: Lobar enlargement with bulging of interlobular fissures can be seen in
severe cases; abscesses, cavitations (with air-fluid levels), and pneumatoceles are
commonly seen; 30-50% of patients develop pleural effusions, half of which are
empyemas.
P aeruginosa: usually all lobes are involved, with a predilection for the lower lobes;
necrosis and cavitation occur frequently; pulmonary vasculitis can produce areas of
pulmonary infarction that radiographically resembles invasive aspergillosis
H influenzae: Pleural effusion is present in approximately half of infected individuals.
Imaging Studies
Aspiration pneumonias:
Gravity-dependent portions of the lungs
(affected by patient positioning)
The right lung is affected twice as often
as the left lung
Chest X-ray
Procedures
Bronchoscopy with or without
bronchoalveolar lavage (BAL):
Lung tissue can be
visually evaluated and bronchial washing specimens
Nonbronchoscopic bronchoalveolar lavage, mini-BAL: BAL can
be performed without the use of a bronchoscope.
Transtracheal aspiration for culture
Thoracentesis:
Essential procedure in patients with a
parapneumonic pleural effusion.
Indications for Etiology
Testing
MORTALITY
The mortality rate ranged from:
5.1 % for combined ambulatory and
hospitalized patients
13 % in hospitalized patients
36 % in patients admitted to the ICU.
PREDICTORS OF MORTALITY
Risk factors at presentation
British Thoracic Society BTS found a 21-fold increase
in mortality in patients who had two or more of the
following findings:
Blood urea nitrogen greater than 20 mg/dL (7
mmol/L)
Diastolic blood pressure less than 60 mmHg
Respiratory rate above 30 per minute
The presence of all three variables predicted a ninefold greater risk for death with 70 % sensitivity and
84 % specificity
PREDICTORS OF MORTALITY
CURB-65 score
These findings plus confusion (based
upon a specific mental test or new
disorientation to person, place, or time)
and age greater than 65 years
Prediction rule for prognosis to
determine whether a patient should be
admitted to the hospital
Severe CAP
Additional criteria that can help determine the need for ICU admission are the
presence of 3 minor criteria that compose the definition of severe CAP.
Minor criteria are as follows:
Respiratory rate greater than or equal to 30 breaths per minute
Ratio of PaO2 to fraction of inspired oxygen (ie, PaO2/FiO 2 ) of less
than or equal to 250
Need for noninvasive ventilation (bilevel positive airway pressure
[BiPAP] or continuous positive airway pressure [CPAP])
Multilobar infiltrates
Confusion/disorientation
Uremia (BUN greater than or equal to 20 mg/dL)
Leukopenia (WBC count <4000 cells/µL)
Thrombocytopenia (platelet count <100,000/µL)
Hypothermia (core temperature <36°C)
Hypotension requiring aggressive fluid resuscitation
Medication
The goals of pharmacotherapy for
bacteria pneumonia are to eradicate the
infection, reduce morbidity, and prevent
complications.
Treatment- CAP
The regimens chosen by the IDSA/ATS guidelines
mainly rely on macrolides (with or without a betalactam) or newer fluoroquinolones for outpatient
therapy
The guidelines promote the use of macrolides to
provide coverage for both S. pneumoniae and
atypical pathogens (particularly, M. pneumoniae
and C. pneumoniae), which account for the
majority of cases of CAP in ambulatory patients
Treatment- CAP
In studies from different regions of the world, atypical
pathogens account for 20 to 30 % of cases of CAP
Recent use of macrolide antibiotics is considered a risk
factor for resistant S pneumoniae
Monotherapy with a macrolide is not recommended
for persons who received a macrolide antibiotic in the
preceding three months.
Treatment
Recommend one of the following oral
regimens for HIGH RISK patients:
A respiratory fluoroquinolone
Combination therapy with a beta-lactam effective against S.
pneumoniae PLUS either a macrolide or Doxycycline
Comorbidities or recent antibiotic use :
The presence of significant comorbidities (ie, chronic obstructive
pulmonary disease [COPD], liver or renal disease, cancer,
diabetes, chronic heart disease, alcoholism, asplenia, or
immunosuppression).
Use of antibiotics within the prior three months, increases the
risk of infection with more resistant pathogens.
Treatment
In previously healthy patients with no exposure to
antibiotics within the previous 90 days, use the
following:
Macrolide
In patients with comorbidities such as chronic disease
of the heart, lung, liver, or kidneys; diabetes mellitus;
alcoholism; malignancy; immunosuppression (drugor disease-induced); or use of antimicrobials within
the last 90 days, use the following:
Respiratory fluoroquinolone or beta-lactam
plus macrolide
Inpatient Treatment
Inpatient empiric antibiotic therapy
Inpatient treatment of pneumonia, should be given within 6 hours of hospital admission (or
in the emergency department if this is where the patient initially presented) and should
consist of the following antibiotic regimens :
Non-ICU patients (choice of one option)
Beta-lactam (IV or IM) plus macrolide (IV or PO)
Antipneumococcal quinolone monotherapy (IV or IM)
Beta-lactam (IV or IM) plus doxycycline (IV or oral)
If patient younger than 65 years with no risk factors for drug-resistant pneumococcus Macrolide monotherapy (IV or oral)
ICU Patients (choice of one option)
Beta-lactam (IV) plus macrolide (IV)
Beta-lactam (IV) plus antipneumococcal quinolone (IV)
If patient has documented beta-lactam allergy - Antipneumococcal quinolone (IV) plus
aztreonam (IV)
Inpatient Treatment
Patients at increased risk of infection with
Pseudomonas (acceptable for both ICU and
non-ICU patients) (choice of one option)
Pseudomonas Aeruginosa
Risk Factors:
ICU
Steroids
ABX > 7 Days in Past Month
CHF
Malnutrition
Cystic Fibrosis
Extrapulmonary Spread Hematogenously
Treat with Antipseudomonals
Inpatient Treatment
Patients at increased risk of infection with
Pseudomonas (acceptable for both ICU and
non-ICU patients) (choice of one option)
Antipseudomonal beta-lactam (IV) plus antipseudomonal
quinolone (IV; PO in non-ICU only)
Antipseudomonal beta-lactam (IV) plus aminoglycoside (IV)
plus one of the following:
Macrolide (IV)
Antipneumococcal quinolone (IV; PO in non-ICU only)
If patient has documented beta-lactam allergy - Aztreonam
(IV) plus aminoglycoside (IV) plus antipneumococcal quinolone
(IV; PO in non-ICU only)
MRSA
For suspected infection with methicillinresistant S aureus (MRSA):
Vancomycin or linezolid may be added
to the antibiotic regimen until the
organism's identity and antibiotic
sensitivities are known, at which point
the medications can be adjusted
accordingly
Aspiration pneumonia
Aspiration pneumonia empiric therapy
ASPIRATION PNEUMONIA
Abnormal Gag and/or
Swallowing Reflex
Pneumonia from Oral
Flora
Aerobes > Anaerobes
Chemical Pneumonitits
from Gastric Acid
Necrotizing, Fulminant
Course
Lung Abscess or
Empyema are Common
Complications
Aspiration pneumonia
Aspiration pneumonia empiric therapy
The causative organisms in aspiration pneumonia have been
noted to be similar to those of CAP or HCAP
Patients with severe periodontal disease, putrid sputum, or a
history of alcoholism with suspected aspiration pneumonia may
be at greater risk of anaerobic infection.
One of the following antibiotic regimens is suggested for such
patients:
Piperacillin-tazobactam
Imipenem
Clindamycin or metronidazole plus a respiratory
fluoroquinolone plus ceftriaxone
SO, Special Circumstances
For Pseudomonas:
Piperacillin-tazobactam, cefepime, imipenem, or
meropenem
Plus
Ciprofloxacin or Levofloxacin
Or
Aminoglycoside and Azithromycin
Or
Aminoglycoside and Fluoroquinolone
For Penicillin-Allergy, Substitute Aztreonam for B-Lactam
For CA-MRSA:
Vancomycin or Linezolid
Clinical response
Clinical response to antibiotic therapy should be
evaluated within 48-72 hours of initiation.
With appropriate antibiotic therapy,
improvement in the clinical manifestations of
pneumonia should be observed in 48-72 hours.
Because of the time required for antibiotics to
act, antibiotics should not be changed within
the first 72 hours unless marked clinical
deterioration occurs.
Clinical response
With pneumococcal pneumonia, the cough usually
resolves within 8 days and crackles heard on
auscultation clear within 3 weeks.
The timing of radiologic resolution of pneumococcal
pneumonia varies with patient age and the presence
or absence of an underlying lung disease.
The chest radiograph usually clears within 4 weeks in
patients younger than 50 years without underlying
pulmonary disease.
Resolution may be delayed for 12 weeks or longer in
older individuals and those with underlying lung
disease.
Clinical response/Failure
If patients do not improve within 72 hours,
an organism that is not susceptible or is
resistant to the initial empiric antibiotic
regimen should be considered.
Secondary to a complication such as
empyema or abscess formation.
Broadening the differential diagnosis to
include noninfectious etiologies such as
malignancies, inflammatory conditions, or
congestive heart failure
Extras
First - Dose of ABX IV, if effective response - change
IV to PO when:
Length of Treatment:
Minimum of 5 days
Afebrile for 48–72 hours
Clinically Stable
Immunizations:
Hemodynamically Stable
Clinically Improving
Able to Ingest RX
Functioning GI Tract
Influenza
Pneumococcal
Smoking Cessation
Pneumonia in
Immunocompromised Pts
Smokers, alcoholics, bedridden, immunocompromised, elderly
Common still common
S. pneumo
Mycoplasma
Pneumocystis Carinii Pneumonia
P. jirovecii
Fever, dyspnea, non-prod cough (triad 50%), insidious onset
in AIDS, acute in other immunocompromised Pts
CXR: bilateral interstitial infiltrates
Steroids for hypoxia
TMP-SMZ still first line
Prevention
Smoking cessation
Vaccination per ACIP recommendations
Influenza
Inactivated vaccine for people >50 yo, those at risk for
influenza compolications, household contacts of high-risk
persons and healthcare workers
Intranasal live, attenuated vaccine: 5-49yo without chronic
underlying dz
Pneumococcal
Immunocompetent ≥ 65 yo, chronic illness and
immunocompromised ≤ 64 yo