5. Pneumonia
o Definition by Microbes
Bacterial – Pneumococcal, Streptococcal
Atypical pathogens
Fungal
Viral
o Definition by Location
Lobar pneumonia
Bronchopneumonia
o Definition by Acquisition
– Community acquired pneumonia
– Hospital acquired pneumonia
– Ventilator-associated pneumonia
6. Pneumonias – Classification
• Community AcquiredCAP
• Health Care AssociatedHCAP
• Hospital AcquiredHAP
• Ventilator AcquiredVAP
Nosocomial Pneumonias
7.
8. Community Acquired Pneumonia
Definition:
Community-acquired pneumonia (CAP) is an alveolar
infection that develops in the outpatient setting or
within 48 hours of admission to a hospital .
CAP is not acquired in a hospital, long-term care
facility, or other recent contact with the health care
system, for 14 days before presentation of the acute
illness .
9. Community Acquired Pneumonia
Definition:
Community-acquired pneumonia (CAP) is an alveolar
infection that develops in the outpatient setting or
within 48 hours of admission to a hospital .
CAP is not acquired in a hospital, long-term care
facility, or other recent contact with the health care
system, for 14 days before presentation of the acute
illness .
10.
11.
12.
13. Respiratory Medicine Session
of the RCPI Masterclass on
Treating the Acutely Ill Patient
Pathogens in CAP
Bacteria
– Streptococcus pneumoniae 50-60%
– Haemophilus influenzae 5-10%
– Staphylococcus aureus 2-5%
– Gram negative bacilli 2%
– Miscellaneous 3-5%
Atypical Agents 10-20%
– Legionella 2-5%
– Mycoplasma pneumoniae 5-10%
– Chlamydia pneumoniae 5%
Viruses 2-15%
Aspiration 5-10%
Streptococcus pneumoniae
14.
15. Pathogens in CAP
No infective cause is found in 30–50% of cases, but in
virtually all studies the most frequently identified
organism is S. pneumoniae .
The ‘atypical’ bacterial pathogens including M.
pneumonaie, Chlamydia pneumoniae and Legionalla
spp. (2–25%)
Viral infections including influenza A and B (8–12%)
are relatively common causes of CAP.
Bartlett. Clin Infect Dis 2000.
16. Pathogens in CAP
Haemophilus influenza and Moraxella catarrhalis are
often associated with COPD exacerbations and
staphylococcal infection may follow influenza.
Alcoholic, diabetic, heart failure and nursing-home
patients are prone to infection with staphylococcal,
anaerobic and Gram negative organisms .
Bartlett. Clin Infect Dis 2000.
17. Ambulatory Patients Hospitalized (Non-ICU)2 Severe (ICU)2
S. pneumoniae S. pneumoniae S. pneumoniae
M. pneumoniae M. pneumoniae Legionella spp.
H. Influenzae C. pneumoniae H. Influenzae
C. pneumoniae H. Influenzae Gram-negative bacilli
Respiratory viruses3 Legionella spp. S. aureus
Aspiration
Respiratory viruses3
1Based on collective data from recent studies
2Excluding Pneumocystis spp.
3Influenza A and B, adenovirus, respiratory syncytial virus, and parainfluenza.
Adapted from File T. Lancet 2003
Most common etiologies of community-acquired
pneumonia
21. Pathophysiology
Pneumonia may occur upon significant inhalation of
virulent microbial pathogens, often combined with
alterations in host defense mechanisms.
Upper and lower airway host defense mechanisms,
including cough and laryngeal protection during
swallowing, as well as protection by airway and
alveolar macrophages and immunoglobulins.
.
22. Pathophysiology
Mechanisms for pneumonia include one or more of
the following: micro-aspiration, macro-aspiration,
and hematogenous spread.
Micro-aspiration occurs commonly in normal hosts,
but a combination of immune mechanisms and the
protective action of the lung cilia help prevent
disease.
Macro-aspiration occurs in patients with abnormal
swallowing mechanisms, as occurs in patients with
stroke or neuromuscular disorders.
.
23. Pathophysiology
Sedative hypnotic drugs and alcohol intoxication are
other important contributors to macro-aspiration.
Patients who suffer from macro-aspiration are prone
to lung abscess formation.
Hematogenous spread to the lungs can occur in
patients with bacteremia, especially in those with a
distant focus of infection, such as a septic joint or
skin ulcer.
.
25. Diagnosis of CAP
1. Evidence of infection (fever or chills and leukocytosis)
2. Signs or symptoms localized to the respiratory system
(cough, increased sputum production, shortness of
breath, chest pain, or abnormal pulmonary
examination)
3. New or changed infiltrate on CXR
29. Diagnosis
All patients admitted to hospital with suspected CAP
should have a chest radiograph performed as soon as
possible to confirm or refute the diagnosis .
The objective of any service should be for the chest
radiograph to be performed in time for antibiotics to be
administered within 4 hours of presentation to hospital
should the diagnosis of CAP be confirmed.
37. Road Map
Once pneumonia is diagnosed, 3 decisions must
quickly be made:
1) Where should the patient be treated: at home, on the
medical ward, or in the ICU?
2) How much testing should you perform, to look for the
pneumonia's causes?
3) Which antibiotic(s) to prescribe?
.
41. Importance of Severity Assessment
A signifcant therapeutic challenge to physicians, as
they have to decide whether the patient is to be
treated in a clinic or a hospital setting.
It is vital to assess the severity of CAP, as it forms a
starting point in the management algorithm and helps
in achieving favorable patient outcomes.
.
42. Importance of Severity Assessment
In community-acquired pneumonia, patients at low-
risk for morbidity or mortality, should preferably be
treated in the outpatient setting .
Generally, outpatient therapy is preferred because it
is cost-effective, favored by patients, promotes faster
convalescence and also reduces the risk of
nosocomial complications.
However, intensive care may be required in severe
cases, which means hospitalization for an extended
period of time.
.
43. Importance of Severity Assessment
Thus, assessing the severity of the illness & whether
it warrants hospitalization is probably one of the most
critical decisions in the overall management of CAP.
Actually , Several scoring systems are available to
help clinicians assess the severity of the illness.
.
44. Prognostic Severity Scales
An assessment of severity is essential for determining
the intensity of the treatment required for the patient
with CAP.
The majority of prognostic severity scales (PSS) were
developed with the idea of converting them into clinical
rules that stratified patients into risk groups based on
the mortality observed at 30 days .
.
45. Prognostic severity scales
.
There are three scoring systems available for
assessing the severity of CAP, these systems aim to
assess the mortality risk associated with the illness .
The three scoring systems are:
1. Pneumonia Severity Index (PSI)
2. CURB 65
3. CRB 65
46. Pneumonia Severity Index
Pneumonia Severity Index is designed to predict CAP
mortality and identify patients who are at a low risk of
death and thus provide outpatient care for this cohort.
It is a mortality prediction tool that was fIrst introduced
by Fine et al. in 1997 .
The rule was validated with 1991 data based on the
Pneumonia Patient Outcomes Research Team (PORT)
cohort study.
.
47.
48. Pneumonia Severity Index
It classifes CAP patients into five categories of an
increased risk for short-term mortality based on 20
variables routinely available at presentation.
Patients classifed in classes I to II are defined as low
risk, as they have a cumulated mortality of <1%
Patients classifed in classes IV and V are defined as
‘high risk, as they have mortality rates between
9 and 30%.
49. Pneumonia Severity Index
Class Points Mortality* Site of Care
I <51 0.1% OutPatient
II 51-70 0.6% OutPatient
III 71-90 2.8% In or OutPatient
IV 91-130 9.5% Inpatient
V >130 26.7% Inpatient
50. The PSI score is assigned after answering
the following three questions:
1) Is the patient >50 years of age?
2) Does the patient have any coexisting abnormalities,
such as neoplastic disease, congestive heart failure,
cerebrovascular disease, renal disease or liver disease?
3) Does the patient have altered mental status, pulse rate
≥125 beats/min& respiratory rate ≥30 breaths/min&
systolic blood pressure <90 mmHg or temperature
<35°C or ≥ 40°C?
52. Pneumonia Severity Index
While the PSI is a relatively reliable tool for mortality
assessment in CAP, there remain some limitations that
prevent its widespread use.
One of the major limitations is that the tool relies
heavily on the age of the patient, which may result in
underestimation of the severity of the illness,
especially in younger patients.
53. CURB 65
CURB 65 is a modifcation of the British Thoracic
Society (BTS) rule in assessing pneumonia mortality
risk. It uses fve variables to arrive at overall death risk
in CAP patients:
1) Presence of confusion (C)
2) Blood urea nitrogen (U) >7 mmol/L (20 mg/Dl)
3) Respiratory rate (R) ≥30/min
4) Blood pressure (B) <90 mmHg systolic or ≤60 mmHg
diastolic
5) Age ≥65 years
54.
55.
56.
57. CURB 65
The CURB-65 is a simple scoring system , simple risk
assessment tool easily used in the outpatient office or
emergency room setting, which assigns 1 point for
each of 5 clinical features.
However, the presence of the blood urea nitrogen
(BUN) as a parameter hampers efficacy, as laboratory
values may not be readily accessible at any given time.
58. CRB 65
Lim et al. also examined the effcacy of this scoring
system after excluding BUN.
They developed a 4-point scale called CRB 65 that
effectively categorizes patients according to the need
for home care, hospital assessment or urgent (ICU)
hospital admission .
61. PSI vs. CURB 65
We recommend CURB 65/CRB 65 over PSI to be used
for judging severity and deciding the site-of-care.
Both PSI and the CURB 65 have several limitations.
These scoring systems are designed primarily to
predict mortality. So, they are infuenced by age and
presence of comorbid conditions.
They are not very effective for predicting ICU admission
and are of limited use in the critical care environment,
The assessment of a different set of parameters is
required for this setting .
62. Need for a New Scoring System to
Define ICU Care
Although,CURB-65 scale can detect high-risk patients
who should be hospitalized, it has major limitations in
overestimating the risk in many of those patients over
65 years of age due to the criterion of age .
CURB-65 scale , Lacks a formal assessment of vital signs
like hypoxemia (does not assess O2 Sat or PaO2), which is
a major drawback as oxygenation needs to be assessed
immediately on arrival at the ED .
63. Risk stratification : Site-of-care decisions
CURB-65 and PSI have been developed and validated
for assisting with the site-of-care decision .
As it pertains to whether to hsopitalize or treat as an
outpatient.
Both instruments demonstrated to decrease emergency
room admission for low-risk CAP patients, without
compromising outcomes.
64. Identifying patients at high-risk for CAP mortality
(who will benefit from ICU admission):
On the other end of the spectrum, the CURB-65 and PSI
have relatively poor predictive value for identifying
patients who will deteriorate after admission, and
subsequently require transfer to an ICU.
Upwards of 20% of patients with CAP admitted to a non-
ICU ward, will require ICU transfer shortly after hospital
admission.
These mis-triaged patients appear to have a significantly
higher in-hospital mortality, compared to patients
admitted directly to the ICU.
66. Predictive Models for Severe CAP
There are three scoring systems available for identifying
severe CAP that necessitates ICU admission , these
include:
1) ATS/IDSA Criteria
2) SMART-COP Rule
3) SCAP Rule
67. Need for a New Scoring System to
Define ICU Care
Although both the PSI and the CURB-65 are useful for
assessing the risk of death, neither was designed for
assessing the need for ICU admission. In contrast,
1) The 2007 ATS/IDSA severity criteria
2) SMART-COP
3) SCAP
Are appropriate for identifying candidates who require
inotropic and/or ventilator support and/or admission to
the ICU
68. IDSA / ATS Criteria for ICU Admission for CAP
Major Criteria (1 or more = ICU admit)
– Endotracheal intubation and mechanical ventilation
Shock requiring vasopressors
Minor Criteria (3 or more = ICU admit)
– Respiratory rate > or = 30 min-1
PaO2-to-FiO2 ratio < or = 250
Multilobar infiltrates
Confusion or delirium
Blood urea nitrogen (BUN) > or = 20 mg/dL
Leukopenia (WBC count < 4000 cells/mm3)
Thrombocytopenia (platelet count < 100,000 cells/mm3)
Hypothermia (core temperature < 36oC)
Hypotension requiring aggressive fluid resuscitation
– Note: These criteria await prospective validation. Physician judgement
should continue to be the primary determinant for patient admission to an
intensive care unit.
76. Why SCAP for Defining Severe CAP?
The SCAP score appears to be ideal for judging the
severity of CAP because it needs only two additional
parameters, compared to the CURB 65 components
[ CXR and ABG ] to judge the severity of the illness.
Chest radiograph would usually be done at the time of
admission as a routine, while ABG facilities are often
available at all tertiary centers.
Additionally, results of both these investigations are
available within an hour. Hence, urgent decisions
regarding the site-of-care can be taken without delay.
77. Key Message
The most popular severity scores, the pneumonia
severity index (PSI) and the British Thoracic Society's
CURB-65 are accurate for predicting pneumonia-related
mortality , but clinical care should be based on a broader
set of medical outcomes than just mortality
78. Key Message
Severity-of-illness scores, such as the CURB-65 criteria
&Pneumonia Severity Index (PSI), can be used to identify
patients with CAP who may be candidates for outpatient
treatment
Once the decision has been made to hospitalize the
patient, other issues should be considered such as the
need to recognize patients who require surveillance in
an ICU due to Severe CAP (SCAP)
80. Case senario
65 y/o male smoker has 2 days of chills, dyspnea,
& purulent sputum. No significant PMHx.
He has felt and eaten poorly. T = 38.1, BP = 110/60,
HR = 95, RR = 20, SaO2 = 89% RA, crackles at the
right apex. He is not confused.
WBC = 15K, Na = 128, K = 3.5, Cl = 105, CO2 = 20.
BUN/creat = 32/1.4. CXR shows RUL infiltrate.
What is your profrssional diagnosis?
81. Thinking about pneumonia: 4 steps
1. Put into initial clinical classification
2. Decide site of care
3. Tests for etiology
4. Initial empiric therapy
82.
83. Put into initial clinical classification
Community-acquired (CAP)
Healthcare-associated (HCAP)
Hospital acquired (HAP)
Ventilator-acquired (VAP)
84. Healthcare-associated Pneumonia
The 2005 ATS and IDSA nosocomial pneumonia guidelines
for the first time incorporated the concept of HCAP ,defined
as pneumonia that occurs in a non-hospitalized patient
with extensive healthcare contact, as defined by one
or more of the following :
Hospitalisation in an acute care hospital for 2 days or more
in the preceding 90 days
Residence in a nursing home or long-term care (LTC) facility
Home intravenous infusion therapy (including antibiotics
and chemotherapy) within the past 30 days
Chronic hemodialysis within the past 30 days
Home wound care within the past 30 days
Exposure to a family member infected with a MDR pathogen
85. CAP vs HCAP/VAP/HCAP
o Healthcare-associated pneumonia (HCAP)
– In hospital > 1 day within past 90 days
– Nursing home/ LTC facility
– Dialysis or outpt hosp within past 30 days
– IV antibiotics or chemo, wound care within 30
days
– Exposure to a Family member with MDRO
o HAP– occurs > 48 hrs after admission & not
incubating at time of admission
o VAP – occurs more than 48 – 72 hrs after intubation
86. Thinking about pneumonia: 4 steps
1. Put into initial clinical classification
2. Decide site of care
3. Tests for etiology
4. Initial empiric therapy
87. CASE
65 y/o male smoker has 2 days of chills, dyspnea,
& purulent sputum. No significant PMHx.
He has felt and eaten poorly. T = 38.1, BP = 110/60,
HR = 95, RR = 20, SaO2 = 89% RA, crackles at the
right apex. He is not confused.
WBC = 15K, Na = 128, K = 3.5, Cl = 105, CO2 = 20.
BUN/creat = 32/1.4. CXR shows RUL infiltrate.
Can I send this patient home?
89. CASE
65 y/o male smoker has 2 days of chills, dyspnea,
& purulent sputum. No significant PMHx.
He has felt and eaten poorly. T = 38.1, BP = 110/60,
HR = 95, RR = 20, SaO2 = 89% RA, crackles at the
right apex. He is not confused.
WBC = 15K, Na = 128, K = 3.5, Cl = 105, CO2 = 20.
BUN/creat = 32/1.4. CXR shows RUL infiltrate.
Can I send this patient home?
90. CURB-65
• Developed by British Thoracic Society
• Confusion, BUN >20, Respiratory rate >30, BP
<90 syst or <60 diast, age >64
– Score = 0 – 1 OUTPT
– Score = 2 WARD
– Score = 3 ICU
94. Case - continued
65 y/o male smoker has 2 days of chills, dyspnea, &
purulent sputum. No significant PMHx.
He drinks alcohol everyday. T = 38.1, BP = 110/60, HR
= 95, RR = 20, SaO2 = 89% RA, crackles at the right
base. He is not confused.
WBC = 15K, Na = 128, K = 3.5, Cl = 105, CO2 = 20.
BUN/creat = 32/1.4. CXR shows RUL infiltrate.
What etiologic tests do I order?
95. Thinking about pneumonia: 4 steps
1. Put into initial clinical classification
2. Decide site of care
3. Tests for etiology
4. Initial empiric therapy
96.
97.
98.
99. Diagnostic tests for etiology
Why not etiologic tests for everyone?
Outpt – Get SaO2; Routine tests for etiology are
optional
Inpt - Blood and sputum cultures recommended for
most (but not all)
ICU - blood and sputum cultures, and Legionella and
pneumococcal UAT
100. How Do I Think About Pneumonia?07/25/2013 100
101.
102. Thinking about pneumonia: 4 steps
1. Put into initial clinical classification
2. Decide site of care
3. Tests for etiology
4. Initial empiric therapy
106. CAP: Empiric Rx
Setting Empiric Rx*
Outpt, healthy w/o
recent abx
Macrolide or doxycycline
Outpt, comorbid disease Respiratory FQ OR
PO Beta-lactam + macrolide
Inpt, non-ICU IV Beta-lactam + macrolide OR Resp
FQ
Inpt, ICU IV Beta-lactam + macrolide OR
IV Beta-lactam + Resp FQ
Without specific risk factors, MRSA or resistant GNR are rare in CAP pts
* Oral BL= amox or amox/cl; IV BL= CTX, cefotaxime, amp/sulb, ertapenem
IDSA CAP Guidelines. Clinical Infectious Diseases 2007; 44:S27–72.
107.
108.
109.
110.
111.
112.
113.
114. CAP: When to consider other bugs?
• When to consider PseA or other resistant GNRs?
– Bronchiectasis or COPD + frequent steroids/antibiotics
– Chronic alcoholism
– Recent hospitalization in last 90 days
• When to consider community acquired MRSA?
– Risk factors: ESRD, IVDA, recent FQ, recent or concurrent
flu
– Presentation: Cavitary/necrotizing PNA or rapid pleural
effusion; Skin lesions; Gross hemoptysis; Severe,
multilobar PNA in young
115. Case - continued
65 y/o male 2 days ago with RUL pneumonia and
treated with ceftriaxone and azithromycin.
On rounds is feeling better, eating, not confused. T =
37.9, HR = 102, BP = 105/75, RR = 12, SaO2 = 88% on
room air
When I can I switch to an oral regimen and what
regimen?
When can the pt go home?
116. Switching to oral
If specific pathogen identified, switch to narrow
spectrum therapy
When clinically improving, hemodynamically stable,
able to take orals, switch to oral rx –
Duration = at least 5 days, and until afebrile for two
days, and have only one sign of clinical instability.
If pathogen is Pseudomonas treat at least 14 days
132. How Do I Think About Pneumonia?07/25/2013 132
133.
134.
135.
136.
137.
138.
139.
140.
141.
142.
143.
144. CAP – What’s New
Increasing recognition of viral pathogens
Consideration of environmental exposures as risk
factor for CAP
Use of PCR (and other tests) to guide initial
antibiotic choice
Use of inflammatory markers to help with diagnosis
and guide therapy
Vaccine efficacy
