PNEUMONIA

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PNEUMONIA. Dr.M.Shahparianpour. Mr. P. 92 yo male w/ h/o fall 3 days prior to admission, came to ER with c/o mental status changes (per NH staff), and 1 day h/o vomiting and dyspnea. Pmhx of alzheimers, emphysema, glaucoma. Meds included 5 different eye drops and donepezil. No drug allergies. - PowerPoint PPT Presentation

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PNEUMONIAPNEUMONIA

Dr.M.Shahparianpour

Mr. P

• 92 yo male w/ h/o fall 3 days prior to admission, came to ER with c/o mental status changes (per NH staff), and 1 day h/o vomiting and dyspnea.

• Pmhx of alzheimers, emphysema, glaucoma.

• Meds included 5 different eye drops and donepezil. No drug allergies.

• Shx: nursing home resident, no recent etoh or tobacco. Daughter involved.

• Pneumovax 2001, flu vaccine 2002.

• PE: T 97.9, rr 22, bp 109/65, p 77, 70% RA oxygen saturation.

• Confused, non-rebreather in place. Heent wnl. Lungs: coarse crackles bilaterally. CV: reg, s1s2, no mrg. Abd: wnl. Ext: +2 ankle edema. Neuro: non-focal, not oriented, following some commands.

• Labs remarkable for wbc 12.6 w/ 90% n, chem 7 wnl, po2 on ABG of 38 mm Hg (ph 7.44)

• CXR w/ ? small RLL infiltrate, but portable film, final read by radiology negative.

Does this patient have Does this patient have pneumonia?pneumonia?In other words, how do youdefine pneumonia?Why is diagnosing pneumonia important?And if he has pneumonia, what kind, and how do you investigate possible causes further?How do you triage the patient?How do you treat him?When do you send him home?Could it have been prevented?

• Pneumonia is defined as inflammation and consolidation of the lung tissue due to an infectious agent.

• Pneumonia that develops outside the hospital setting is considered community-acquired pneumonia

• Pneumonia developing48 hours or more after admission to the hospital is termed nosocomial or hospital-acquired pneumonia.

• Community-acquired pneumonia is caused most commonly by bacteria that traditionally have been divided into 2 groups, typical and atypical.

• Typical organisms include S pneumoniae (pneumococcus) and Haemophilus and Staphylococcus species.

• Atypical refers to pneumonia caused by Legionella, Mycoplasma, and Chlamydia species.

Definition (per IDSA) Acute infection of the pulmonary Acute infection of the pulmonary parenchyma accompanied byparenchyma accompanied by:

• Acute infiltrate on CXR or auscultatory findings consistent with pneumonia

• And usually two of the following: fever or hypothermia, rigors, sweats, new cough with or without sputum (or change in color), chest discomfort, dyspnea.

• In the elderly, more common to be afebrile/hypothermic, and altered mental status afebrile/hypothermic, and altered mental status sometimes is the ONLY complaint.sometimes is the ONLY complaint.

PneumoniaPneumonia• CommunityCommunity

• NosocomialNosocomial

• Eldery houseEldery house

• Immunocompromised hostImmunocompromised host

• Immunocompromised hostImmunocompromised host

• Community-acquired pneumonia remains a common illness.

• pneumonia is reported to be 170 cases per 100,000 persons.

• Estimates of incidence of nosocomial pneumonia range from 4-7 episodes per 1000 hospitalizations.

• Approximately 25% of patients in intensive care units (ICUs) develop pneumonia.

• 20% result in hospitalization• With advancing age, the

incidence increases 3 folds 3 folds in patients( aged 44 years to 65 years)

• Pneumonia as a cause of hospitalization increased from 36 to 48 cases per 100,000 persons between 1984 and 1995.

• Pneumonia is the sixth leading cause of death

• the most common infectious causes of death.

• The mortality rate is reported to be 1% in the outpatient setting but may increase to up to 25% in those requiring hospital admission.

• In a patient with preexisting respiratory disease, onset of bacterial pneumonia may result in deterioration of respiratory status, leading to respiratory failure and death.

• Nosocomial pneumonia is the leading cause of death among hospital-acquired infections.

• Recent studies have shown that

nosocomial pneumonia causes excessive risk of death, and the mortality rates range from 20-50%.

• Although less common in the antibiotic era, bacterial pneumonia may lead to bronchiectasis.

• However, lower respiratory infection with pneumococci, staphylococci, and Klebsiella species may result in bronchiectasis, especially if treatment is delayed.

• Incidence is greater in males than in females.

• Advanced age increases the incidence of pneumonia and the mortality from pneumonia.

• Elderly persons have • weaker immune responses, • higher risk of aspiration, • comorbidities.

• Resistant bacteria are becoming an increasing problem, which affects treatment.

• We have an increasing population with immunosuppression or chronic diseases (which impacts cause and mortality)

Pathogenesis of typical pneumonia

• S pneumoniae generally resides in the nasopharynx and is carried asymptomatically in approximately 50% of healthy individuals.

• Invasive disease may occur upon acquisition of a new epithelium serotype.

• A strong association exists with viral illnesses, such as influenza.

• Viral infections increase pneumococcal attachment to the receptors on activated respiratory epithelium.

• Once aspirated from the nasopharynx to the alveolus, pneumococci infect type II alveolar cells.

• The pneumonic lesion progresses as pneumococci multiply in the alveolus and invade alveolar epithelium.

• Pneumococci spread from alveolus to alveolus through the pores of Kohn, thereby producing inflammation and consolidation along lobar compartments.

Pathogenesis of atypical infection • After inhalation, the atypical

organisms attach to the respiratory epithelial cells by a variety of mechanisms.

• The presence of pili on the surface of Legionella species facilitates attachment.

• Once adhered, the organisms cause injury to the epithelial cells and their associated cilia.

• Many of the pathogenetic mechanisms may be immune-mediated rather than due to direct injury by the bacteria.

• A host defense is mounted via cell-mediated and humoral immunity.

• Infection caused by atypical organisms often spreads beyond the lobar boundaries and frequently is bilateral.

Pathogenesis of nosocomial pneumonia • Aspiration plays a central role in the

pathogenesis of nosocomial pneumonia.• Approximately 45% of healthy subjects

aspirate during sleep, and an even higher proportion of severely ill patients aspirate routinely.

• Depending on the number and virulence of the pathogenic organisms reaching the lower respiratory tract and on the host defense factors, pneumonia may develop.

• The oropharynx of hospitalized patients may become colonized with aerobic gram-negative bacteria within a few days of admission.

• Therefore, nosocomial pneumonia is caused predominantly by the gram-negative bacilli.

• However, the incidence of Staphylococcus aureus lower respiratory tract infection is increasingly common in the hospitalized and institutionalized patient and must now be considered a possible pathogen for nosocomial pneumonia.

PneumoniaDecisions

•PORT PORT

•MicrobiologyMicrobiology •Empiric TherapyEmpiric Therapy

PneumoniaRoutes of Transmission

• InhalationInhalation

• AspirationAspiration

• Blood-borneBlood-borne

Community Acquired PneumoniaCommunity Acquired Pneumoniaetiologyetiology

S.pneumoniaeS.pneumoniae

H.influenzaeH.influenzae

M.pneumoniaeM.pneumoniae C.pneumoniaeC.pneumoniae

L.pneumophiliaL.pneumophilia

AnaerobesAnaerobes

OtherOther

Community - AcquiredCommunity - Acquired• BacteriaBacteria % Cases% Cases• Streptococcus pneumoniae 50-70• Hemophilus influenzae 10-15• Staphylococcus aureus 5• ““AtypicalAtypical””• Mycoplasma pneumoniae 10-30• Chlamydia pneumoniae 10-20• VirusVirus• Influenzae

Epidemic• Adenovirus

Community PneumoniaCommunity PneumoniaMicrobiologyMicrobiology

• Unusual / Don’Miss• PCP• Tb• Moraxella• Legionella

• Very Unusual• Hantavirus• Fungi (cocchisto)• Anthrax, SARS

Different categories of Different categories of pneumonia and common pneumonia and common

pathogenspathogens• Patients w/ minimal co-morbidities (cause

identified only 50% of the time):• S. pneumoniae (most common overall)• M. pneumoniae/C. pneumoniae• Viruses

• Chronic pulmonary/cardiovascular disease:• Drug resistant S. pneumoniae• H. influenza• M. catarrhalis• Legionella

• Nosocomial (hospitalized or nursing home patients):• Resistant GNR’s• Pseudomonas aeruginosa• S. aureus (MRSA)• Aspergillosis• Anaerobes (aspiration)

• In alcoholics:• Klebsiella pneumoniae, anaerobes, TB

• IVDU:• S. aureus, PCP, anaerobes

• Post-splenectomy:• S. pneumoniae, H. influenza

• HIV/AIDs:• PCP, S. pneumonia, TB, fungal

• Leukemic patients/bone marrow transplant:• Aspergillosis, legionella, CMV, other fungal.

• Post influenza:• S. pneumoniae, S. aureus

• Cystic fibrosis:• Pseudomonas aeruginosa, S. aureus

• In patients who have received solid organ transplants, pneumonia from S pneumoniae may occur more than 3 months after the transplant.

• Other organisms include Legionella species, Pneumocystis carinii, and cytomegalovirus.

• Sickle cell disease may indicate S pneumoniae or H influenzae infection.

• Diabetic ketoacidosis may lead to S pneumoniae or S aureus infection

• Animal exposure:• C. psittaci, Cryptococcus neoformans,

Histoplasmosis capsulatum (birds)• Tularemia (rabbit), plague (rat), hantavirus

(deer mouse), H. capsulatum (bat).• Q fever (C. burnetii) – farm animals

• Travel:• SARS (Asia), coccidiomycoses, (SW USA),

Legionella (endemic/epidemic areas).

This sputum smear shows staphylococcus bacteria using Gram stain technique in a patient with staphylococcal pneumonia.

                                                                                                                                                                                                                  

A photomicrograph of Streptococcus spp. bacteria using Gram stain technique.

                                                                                                                                                                                                                  

Scanning electron micrograph of S. pneumoniae

Photomicrograph of Streptococcus pneumoniae bacteria revealing capsular swelling using the Neufeld-Quellung test.

                                                                                                                                                                                   

Pneumocystis carinii, now called P. jiroveci, is present in this lung impression smear, using Giemsa stain.

                                                                                                                                                                                                                  

A photomicrograph of Pseudomonas aeruginosa bacteria.

                                                                                                                                                                                          

Photomicrograph of Haemophilus influenzae as seen using a Gram stain technique.

                                                                                                                                                                  

MYCOPLASMA

History • Clinical presentation in patients with pneumonia varies

from a mildly ill ambulatory patient to a critically ill patient with respiratory failure or septic shock.

• The character of sputum produced may

suggest a particular pathogen.

• Patients with pneumococcal pneumonia may produce bloody or rust-colored sputum.

• Infections with Pseudomonas, Haemophilus, and

pneumococcal species are known to expectorate green sputum.

• Anaerobic infections characteristically produce foul-smelling and bad-tasting sputum.

• Currant-jelly sputum suggests pneumonia from Klebsiella

or pneumococcal species.

• Patients may report rigors or shaking chills.

• Patients may complain of other nonspecific symptoms, which include headaches, malaise, nausea, vomiting, and diarrhea.

• These symptoms may suggest infection with Legionella, Chlamydia, or Mycoplasma species.

• Malaise, myalgias, and exertional dyspnea may be observed.

• Pleuritic chest pain or abdominal pain secondary to pleuritis is a common feature of pneumococcal infection, but these may occur in other bacterial pneumonias.

Physical examination • Physical examination findings vary

depending on the type of organisms, severity of pneumonia, coexisting host factors, and presence of complications.

• The common findings of consolidation are as follows:

• Fever or hypothermia (temperature >38.5°C or <36°C)• Tachypnea (respiratory rate >18 breaths per min)• Tachycardia or bradycardia• Central cyanosis• Dullness to percussion over pneumonic consolidation• Decreased intensity of breath sounds• Rales or crackles• Egophony upon auscultation• Whispering pectoriloquy• Pleural friction rub• Altered mental status

• Physical examination findings that may indicate the etiology of pneumonia are as follows:

• Periodontal disease with foul-smelling sputum - Anaerobes, possible mixed aerobic-anaerobic infection

• Bullous myringitis - Mycoplasma pneumoniae• Absent gag reflex, altered level of consciousness,

recent seizure - Polymicrobial (aerobic and anaerobic), possible macroaspiration or microaspiration

• Encephalitis - M pneumoniae, C burnetii, L pneumophila

• Cerebellar ataxia, erythema multiforme, erythema nodosum - Chlamydia pneumoniae, M tuberculosis

• Erythema gangrenosum - Pseudomonas aeruginosa, Serratia marcescens

• Cutaneous nodules (abscesses and CNS findings) - Nocardia species

Lab Studies

• Leukocytosis with a left shift, although commonly observed in any bacterial infection, may be may be absent in patients who are elderly absent in patients who are elderly or debilitated.or debilitated.

• LeukopeniaLeukopenia (defined as a WBC count of <5000) is an ominous ominous sign sign of impending sepsis and portends a poor outcome.

• Sputum examination provides an accurate diagnosis in approximately 50% of patients.

• An adequate specimen must have less than 10 squamous epithelial cells and more than 25 WBCs per low-power field.

• However, the number of WBCs in the sputum of a neutropenic patient may be fewer than 25 WBCs per low-power field, despite origination from the lower respiratory tree.

• A single pathogen present on the Gram stain is indicative of pneumonia;

• mixed flora may indicate oral contamination or anaerobic

infections.

• An adequate specimen uncontaminated by oral flora is required for a proper workup.

• Sputum cultures are submitted only from specimens that are deemed satisfactory after Gram stain.

• Other tests may include the following:• Urinary antigen testing for Legionella serogroup 1 has a high

yield.

• A urinary antigen test for pneumococcus is available and may be performed at the bedside.

• A Legionella serum antibody titer rising by 1:128 confirms the

diagnosis retrospectively. Mycoplasma and Chlamydia immunoglobulin M antibodies contribute to the diagnosis.

• Serology is essential in the diagnosis of unusual causes of pneumonia such as Q fever and brucellosis.

• Culture and Gram stain of pleural effusions or empyema fluid has a high yield.

• Pleural fluid pH determination should be made to classify the effusion as simple versus complicated.

• The Legionella-specific direct fluorescent antibody test is performed when indicated, even though this technique is associated with a high rate of false-negative results

• Performing blood cultures is important, but the results have a limited value.

• When positive, the results confirm a causative agent.

• Blood cultures are positive only in approximately 40% of cases,

Imaging Studies

Chest radiograph findings may indicate the following:

• In a patient with a clinical picture of pneumonia, pathogenic organisms may be suggested based on the chest radiographic pattern.

• The common patterns are described as follows:• Focal opacity (segment or lobar pneumonia) - S

pneumoniae, M pneumoniae, L pneumophila, S aureus, C pneumoniae, M tuberculosis, B dermatitidis

• Interstitial pattern (diffuse process identified as reticulonodular or reticular process) - M pneumoniae, P carinii, C psittaci

• Interstitial pattern with hilar and/or mediastinal lymphadenopathy - Epstein-Barr virus, Francisella tularensis, C psittaci, M pneumoniae, fungi

• Cavitation or necrotizing pneumonia - Mixed aerobic-anaerobic infection (lung abscess), aerobic gram-negative bacilli, M tuberculosis, L pneumophila, C neoformans, Nocardia asteroides, Actinomyces israelii, C immitis

• Bulging oblique or horizontal fissure - K pneumoniae, L pneumophila

• Multifocal bilateral segment or lobar opacities - S aureus, C burnetii, L pneumophila, S pneumoniae

• Miliary (diffuse micronodular) pattern - M tuberculosis, H capsulatum, C immitis, B dermatitidis, varicella zoster

• Pneumatoceles (thin-walled cavities) - S aureus, Streptococcus pyogenes, P carinii

• "Round" pneumonia (often presents as solitary pulmonary nodule) - C burnetii, S pneumoniae, L pneumophila, S aureus

• Bronchoscopy: Bronchial washing specimens can be obtained.

• Protected brush and bronchoalveolar lavage can be performed for quantitative cultures.

• Transtracheal aspiration for culture:• This procedure is mentioned primarily

for historical significance. This method of obtaining lower respiratory secretions has been replaced by fiberoptic bronchoscopy.

• Thoracentesis: This is an essential procedure in patients with a parapneumonic pleural effusion.

Triage (home, admit, step down, ICU)

• Decision based on patient’s clinical condition, risk of death and complications, presence of other medical problems, social support.

• Age more than 65 yo alone is not an indication for admission.

• All patients withAll patients with new hypoxemia (sat <90% or Po2 <60mm new hypoxemia (sat <90% or Po2 <60mm

Hg), Hg), hemodynamic instability** should be hemodynamic instability** should be

hospitalizedhospitalized.

Pneumonia Severity Index (PSI)

• Based on data available at presentation (age, coexisting illnesses, findings on PE, lab and radiographic findings).

• Stratifies patients into five risk classes.

• 30 day mortality estimated for each risk class (.1%-27%).

• Patients in risk class I-III at low risk of death – most can be safely treated as outpatient.

Risk class IV and V should definitely be hospitalized (for both consider step-down bed, or ICU for class V).

Diagnosis of CAPDiagnosis of CAP

Can CAP be reliably differentiated from other respiratory conditions by clinical features alone?

NO The diagnosis of CAP on the basis

of history and physical findings is inaccurate without a chest radiograph.

Nosocomial PneumoniaMajor FactorsMajor Factors::

• Alteration oropharyngeal flora

• Aspiration

• Contaminated aerosol nebulizers

• Attendant’s hands

• Injudicious use antibiotics

Pneumonia Pneumonia MicrobiologyMicrobiology

• Organisms

• Acquired % hospital community• Strep pneumonia 5 50• Staph aureus 15 5• Pseudomonas aerug 31 2• Klebsiella 12 1• Enterobacter 15 1• Hemophilus 1 10• Anaerobes 2 5• Atypical 2 30

Pneumonia Pneumonia Physiologic ImpairmentPhysiologic Impairment

•Hypoxemia (low V/Q)•shunt•Hyperventilation

(low PCO2, high pH)•Restriction

Elderly Patients with CAPElderly Patients with CAP

• Classic symptoms and signs of pneumonia less likely

• Non-specific symptoms especially confusion, more likely

• Comorbid illness more common• Higher mortality rate• Fever less likely• Aspiration is a risk factor

AlgorithmPatient with community-acquired pneumoniaPatient with community-acquired pneumonia

Is the patient > 50 years of ageIs the patient > 50 years of age

Assign patient to Assign patient to risk class II-V risk class II-V

based on based on prediction mosel prediction mosel scoring systemscoring system

Does the patient have a history of any of the Does the patient have a history of any of the following comorbid conditions ?following comorbid conditions ?

Neoplastic diseaseNeoplastic diseaseCongestive heart failureCongestive heart failureCerebrovascualr diseaseCerebrovascualr diseaseRenal diseaseRenal diseaseLiver diseaseLiver disease

Does the patient have a history of any of the Does the patient have a history of any of the following abnormalities on physical examinationfollowing abnormalities on physical examination

Altered mental statusAltered mental statusPulse ≥ 125 / minutePulse ≥ 125 / minuteRespiratory rate ≥ 30 / minuteRespiratory rate ≥ 30 / minuteSystolic blood pressure < 90 mmHgSystolic blood pressure < 90 mmHgTemp < 35° C or ≥ 40° CTemp < 35° C or ≥ 40° C

Assign patient to risk class IAssign patient to risk class I

YesYes

YesYes

YesYes

NoNo

NoNo

NoNo

Patient Pointscharacteristics assignedDemographic factors Age: males age (in yrs) females age (in yrs) -10 Nursing home resident +10 Comorbid illnesses Neoplastic disease +30Liver disease + 20 Congestive heart failure +10 Cerebrovascular disease +10 Renal disease +10

Physical examination findings Altered mental status +20 Respiratory rate ≥ 30/mi +20 Systolic blood pressure < 90 mmHg +20 Temp. < 35° C or ≥ 40° C +15 Pulse >125 / min +10

Laboratory findings pH < 7.35 +30 BUN > 10.7 mmol/L +20 Sodium < 130 mEq/L +20 Glucose > 13.9 mmol/L +10

Hematocrit < 30% +10 PO < 60 mmHg2 +10 Pleural effusion +10

Prediction model for C A PPrediction model for C A P

Stratification of Risk ScoreStratification of Risk Score

Risk Risk class Based on I Algorithm

Low II < 70 total pointsModerate lll71-90 total points

IV 91-130 total pointsHigh V > 130 total points

Flow Chart Approach to Treating Outpatients and Inpatients with C.A.P.

Patient with suspected pneumoniaPatient with suspected pneumonia

Chest radiographChest radiograph

Decision to hospitalizeDecision to hospitalize

Hospitalized patientHospitalized patientManaged as Managed as outpatientoutpatient

Expectorated sputumExpectorated sputumSputum for stain (optional)Sputum for stain (optional)

Empirical antibioticEmpirical antibiotictreatemnttreatemnt

No rapidNo rapiddiagnosticdiagnostic

test positivetest positiveGram stainGram stain

or other rapidor other rapidtest identifiestest identifies

likely pathogenlikely pathogen

Subsequent data (blood Subsequent data (blood culture, sputumculture, sputum

culture, etc.) yields culture, etc.) yields likely pathogenlikely pathogen

Antibiotic treatmentAntibiotic treatmentselected forselected for

pathogenpathogen

EmpiricalEmpiricaltreatmenttreatment

EmpiricalEmpiricaltreatmenttreatment

No sputumNo sputum

Risk-Class Mortality Rates for Patients with Pneumonia

Risk Mortality Recommendationsclass No. of points (%) for site of care

I No predictors 0.1 Outpatient

II < 70 0.6 Outpatient

III 71- 90 2.8 Inpatient (briefly)

IV 91 - 130 8.2 Inpatient

V > 130 29.2 Inpatient

CORE ADVERSE PROGNOSTICCORE ADVERSE PROGNOSTIC

FEATURES (CURB SCORE)FEATURES (CURB SCORE) Confusion : Abbreviated Mental Test

score of 8 or less Urea : raised >7mmol/l (for patients

being seen in hospital) Respiratory rate: raised ≥30/min Blood pressure: low (systolic <90 mmHg

and/or diastolic ≤60 mmHg)These features (except Urea) should be

assessed for ALL patients.

The Abbreviated Mental TestThe Abbreviated Mental TestEach question scores 1 mark, total Each question scores 1 mark, total

10marks10marks

• Age• Date of birth• Time (to nearest

hour)• Year• Hospital name

• Recognition of two persons

• Recall address• Date of major

event• Name of monarch

(president)• Count backwards

20 →1

“Pre-existing” Adverse Pre-existing” Adverse Prognostic FeaturesPrognostic Features

• Age 50 years and over• Presence of coexisting diseaseCongestive cardiac failureCoronary artery diseaseStrokeDiabetes mellitusChronic lung diseaseCancer

“Additional” Adverse Prognostic Feature

If available to some GPs who have oximeters.

• Hypoxaemia (Sao2 <92% or Pao2

<8kPa)

1 feature presentNone present 2 or more features present

Consider “pre-existing” adverse

prognostic features

Consider “additional “adverse prognostic feature if available

Home management*

Clinical judgement

Refer to hospital

Consider “core” adverse prognostic features

YES

NO

Associated Mortality Associated Mortality by Age and Treatmentby Age and Treatment

Age Mortality

18-64 yr 10% - 15%

65-74 yr 20%

75-84 yr 30%

> 85 yr 40%

Untreated 50% - 90%

Patient PreferencePatient Preference:Inpatient vs. Outpatient Inpatient vs. Outpatient

TherapyTherapy

80% 74%

9%

0%

20%

40%

60%

80%

Patients FavoringOutpatient Therapy

Patients willing to pay

24% of Monthly Income to Ensure

Outpatient Therapy

Patients FavoringInpatient Therapy

Antibiotic Decision MakingAntibiotic Decision Making

• Severity of disease

• Microbiology environment

• Patient

• Host status

• Individual considerations

• Practice Guidelines

Antibiotic UseAntibiotic Use

• Empiric oral vs.. parenteral

• Loading dose

• Dosing

• Speed of delivery

• Switch to oral from IV

• Duration of therapy

Bacteriology of Hospital-Bacteriology of Hospital-Acquired PneumoniaAcquired Pneumonia

Early-Onset Late-OnsetPneumonia Pneumonia Other

S pneumoniae P aeruginosa Anaerobic bacteria

H influenzae Enterobacter sp Legionella pneumophilia

Moraxella cattarrhalis Acinetobacter SP Influenza A and B

S aureus K pneumoniae Respiratory syncitial virus

Aerobic gram-negative bacilli S marcenscens Fungi

E coli

Other gram-negative bacilli

S aureus

PREVENTION

Vaccination strategiesInfluenza vaccinePneumococcal vaccine

Pneumococcal vaccine

• Pneumococcal vaccine: contains purified capsular polysaccharide from the 23 serotypes that cause 85-90% of the invasive pneumococcal infections in adults and children in the United States.

• Cost-effective among individuals over the age of 65 for prevention of bacteremia.

• Benefit has been shown in some studies for patients with diabetes, CHF, chronic pulmonary disease, asplenia.

• Effectiveness has not been proven in immunosuppressed, but still recommended.

• Antibody response declines over 5-10 years.

• Revaccination after 5 years given to patients who received initial vaccination when less that 65 yo age, asplenic patients, and immunocompromised.

• Influenza vaccine: modified annually to reflect the anticipated strains in the upcoming season.

• The vaccine virus is grown in eggs, purified, and inactivated (does not contain live virus).

• Efficacy can range from 70-90%. Shown to reduce all-cause mortality during influenza season by 27-54%.

Influenza vaccine

• Groups that benefit: age>65, residents of nursing homes, patients with chronic lung or cardiovascular disease, people frequently hospitalized, pregnant women in 2nd/3rd trimester, health care providers, HIV patients, travelers to foreign countries during influenza epidemics.

• Need vaccination yearly (Sept – Feb).

• New, live attenuated virus vaccine only for children and healthy adults <age 50.

.

The end

INFLUENZA VACCINE• Primary influenza pneumonia is

rare and carries a high mortality rate

• Secondary bacterial pneumonia is more common notably due to S aureus

• Bronchitis is also a common complication

• The greatest mortality is in those patients with underlying disease

INFLUENZA VACCINE

Evidence on Efficacy Based on several large well

designed case-control field studes from North America

Other studies from UK and Netherlands

INFLUENZA VACCINE

Results of Studies:-Reduces hospital deaths from

pneumonia and influenza by about 65% and from all respiratory causes by 45%

Decreases hospital admissions and outpatient visits

PNEUMOCOCCAL VACCINERecommendations in U.K.

AspleniaSevere spleen dysfunctionChronic renal diseaseChronic heart diseaseChronic lung diseaseChronic liver diseaseDiabetes mellitusImmunosuppression/Immunodeficiency

PNEUMOCOCCAL VACCINEEFFICACY STUDIES

• Protection offered of around 66% against definitive pneumococcal pneumonia with bacteraemia for “normal” or “low risk” adults .

• NO evidence that vaccine is effective in “high risk” groups and in those aged 60 to 70 years.

NOSOCOMIAL PNEUMONIA

Disease Definition new cough auscultatory findings new infiltrate or progressive

infiltrate(s) on chest radiograph, accompanied by: fever or hypothermia, leukocytosis,

sputum production Etiology: polymicrobial

Disease Definition - cont’d

Acquired by a patient in the following settings: in a hospital or long-term-care facility

after being admitted for >48 hours or

<7 days after a patient is discharged from hospital ( patient’s initial hospitalization should be 3 days duration )

Risk Factors

Host factors ( e.g. extremes of age, severe underlying disease )

Colonization by gram-negative microorganisms

Aspiration or reflux Prolonged mechanical ventilation Factors that impede adequate

pulmonary toilet

Problems in Diagnosis of NP Clinical criteria lack specificity No “gold standards” for diagnostic

procedures (e.g. invasive procedures) High potential for more than one ongoing

infectious process Use of antimicrobials in ICU empirically or

use for infections of other sites or organs.

Recommended