An Approach To Community Acquired

PneumoniaLaura Miles, Pediatrics Resident

Otto Vanderkooi, Infectious Disease Specialist

Based on the 2011 clinical practice guidelines from the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America

What it does cover:

Children and Infants over 3 months of age

Community acquired pneumonia

Otherwise healthy patients

Inpatients or outpatients

What it does not cover:

Infants under 3 months of age

Immunocompromised patients

Children with home ventilation devices

Children with underlying chronic disease

Children with underlying lung disease (eg cystic fibrosis)

WHO definitions

For resource poor areas pneumonia defined as:Cough or difficulty breathing + age adjusted

tachypnea

Severe pneumoniaCough or difficulty breathing + 1 of:

Lower chest indrawing Nasal flaring Grunting

WHO definitions

Very severe pneumoniaCough or difficulty breathing + 1 of:

Cyanosis Severe respiratory distress Inability to drink or severe vomiting Lethargy/unconsciousness/convulsions

These classifications not well validated in resource rich areas

Signs of Respiratory Distress Tachpnea

0-2 mo >60 2-12 mo >50 1-5 yrs > 40 > 5 yrs >20

Dyspnea

Retractions

Grunting

Nasal Flaring

Apnea

Altered Mental Status

Pulse oximetry measurement < 90% in room air

Definitions

Simple pneumonia Bronchopneumonia

Primarily involving airways and surrounding interstitium Lobar pneumonia involving a single lobe

Complicated pneumonia Parapneumonic effusion Multilobar disease Abscess Cavities Necrotizing pneumonia Empyema Bronchopulmonary fistula Pneumothorax

What bugs are we treating?

Viral (RSV, adenoviruses, bocavirus, influenza viruses, coronavirus)

Strep pneumoniae

Group A Streptococcus

Staph MSSA MRSA

Haemophilus Influenzae Typeable Non-typeable

Mycoplasma Pneumonia

Chlamydia Trachomatis or Chlamydophilia Pneumonia

Hospitalization?

Clinical severity of illness – ‘toxic appearance’

Hypoxemia (<90%)

Infants < 3-6 months of age

Suspected bug with increased virulence (eg MRSA)

Concern about home environment

Unable to take adequate PO

Many adult scoring systems – not validated in pediatrics

Predictors of outcome

Hypoxemia (<90%)

Tachypnea In study using WHO defined tachypnea

20% of tachypneic children had pneumonia vs 12% of children who weren’t tachypneic

Retractions and grunting

Head bobbingStatistically associated with tachypnea

Guidelines for ICU Admission

Impending respiratory failure

O2 sat < 92 % on greater than 50% FiO2

Altered mental status

Need for blood pressure support

Severity of illness scores don’t provide enough information alone to decide – use the overall clinical pictures

Guidelines for ICU admission

Underlying pathogen plays a significant role in severity of illness In patients with invasive pneumococcal infection

with with concurrent viral infection More likely to need ICU admission Prolonged ICU stay

2 retrospective case studies, MRSA pneumonia High incidence of necrotizing pneumonia Need for ICU care Higher mortality

Investigations

Investigations – Blood Cultures

Blood cultures should not be obtained in fully immunized patients managed as outpatients

Should be obtained: Patients failing initial therapy Mod-Severe pneumonia requiring admission

In improving patients, positive culture should not preclude discharge

Repeat blood cultures in improving patients not necessary to document resolution of pneumococcal bacteremia

Repeat cultures should be obtained in children with documented Staph Aureus

Investigations – other tests

Sputum samples should be obtained in hospitalized patients who can produce sputum

Urinary antigen tests not recommended for diagnosis of pneumococcal pneumonia in pediatric patients

Test for respiratory viruses should be sent on all admitted patients

No need for antibacterial therapy in patients with positive viral test and no evidence of bacterial co-infection on clinical assessment or laboratory or imaging investigations

Investigations – atypical bacteria

If signs and symptoms suspicious for M. pneumoniae – should be tested to help guide antibiotic selection

Diagnostic testing for C. pneumoniae not recommendedNo reliable and readily available testing

Investigations - CBC

Routine measurement of CBC not necessary for children managed as outpatients

Should be obtained for patients with more serious disease

Investigations – Acute phase reactants

ESR,CRP should not be used as sole determinant of bacterial vs viral pneumonia

Don’t routinely measure in fully immunized children managed as outpatients

In patients with more severe disease – may be useful to assess response to therapy in conjunction with clinical assessment

Investigations - CXR

Not routinely needed in patients treated with outpatients

Should be performed in all patients with hypoxemia or significant respiratory distress

Should be performed in patients with failed antibiotic therapy

Repeat CXR not required in patients who recover well

Routine daily x-rays not required for patients who remain stable post VATS or chest tube insertion

Investigations - CXR

f/u X ray should be performed 4-6 weeks later patients with recurrent pneumonia in the same lobe lobar collapse on initial x-ray or any suspicion for anatomic anomaly or suspicion for foreign body aspiration

Antimicrobial Therapy

In a preschooler diagnosed with community acquired pneumonia and treated as an outpatient, how should you treat?

Antimicrobial Therapy

Not routinely needed in preschoolers diagnosed with CAP – most commonly viral pathogens

Amoxicillin first line therapy for outpatient treatment forFully immunized infants and preschool children with

CAP believed to be bacterialFully immunized and previously well school aged

children with mild to moderate CAP Note: consider atypical coverage

Antimicrobial Therapy

Macrolides first line for atypical pathogensShould perform laboratory testing

Influenza treatmentAs soon as possible for patients with infection

consistent with influenza related CAPDo not delay treatment while waiting for testing

Antimicrobial Therapy - Inpatients

Ampicillin or Penicillin G first line in areas without high S. Pneumo resistance rates

Third generation Cephalosporin (Ceftriaxone, Ceftoaxime) if:Not fully immunizedHigh level of penicillin resistanceLife threatening infection, including empyema

Antimicrobial Therapy - Inpatients

VancomycinNot been shown to be more effective than 3rd

generation Cephalosporin in treatment of S. PneumoAdd if concern for Staph Aureus

MacrolideAdd if concern about atypical pneumonia – should

perform diagnostic testing

ACH Guidelines:

Jan 2009 – Dec 2011 93% of Strep Pneumo cultured sensitive to Penicillin96% sensistive of Cefotaxime

Empiric Antibiotic Guidelines PICU:Severe community acquired pneumonia

Ceftriaxone Vancomycin Clarithromycin PO or Azithromycin IV Oseltamivir (seasonal)

Duration of Therapy

Treatment regimens of 10 days well studiedShorter might be ok

MRSA may require longer treatment than S. pneumo

Parapneumonic Effusions

Parapneumonic Effusions

Collection of fluid in the pleural space with associated pneumonia

Occur in 2-12% of patients with community acquired pneumonia

May occur in up to 20% of patients with M. pneumonia

Seen in ~10% of viral pneumonias

Parapneumonic Effusions

What determines the need for drainage?Size of the effusion

Small effusions can be effectively treated with antibiotics

Degree of respiratory distress

Effusion Size Criteria

Mostly subjective

Small effusion< 10 mm rim of fluid on lateral decubitus< ¼ of hemithorax opacified on upright CXR

Large effusion> 50% of hemithorax is opacified

Moderate effusion In between

What Needs Drainage?

Moderate effusion associated with respiratory distress

Large parapneumonic effusion

Empyema

Diagnostic purposes ? Concern about malignancy

How to Drain?

Both chest thoracostomy tubes (with the addition of fibrinolytic agents ie TPA) and VATS have been shown to be effective

Both associated with decreased morbidity compared to chest tube alone

In non-loculated effusions – chest tube alone may be a reasonable first option

Next Steps

Consider stepping up to VATS or open decortication post chest tube insertion (+/- fibrinolytic therapy) if:Persistence of moderate or large effusion after 2-3

daysPersistence of respiratory distress after 2-3 daysPersistence of fever alone is not a sign of failure

Next Steps

Should perform CT chest to assess adequacy of drainage, assess for loculation or necrotizing parenchymal disease

Open thoracotomy with decortication is sometimes necessary post VATS but associated with higher morbidity

Chest Tube Removal?

Absence of intrathoracic air leak

Chest tube drainage less than 1 ml/kg/24h (but usually calculated over 12 hours)

Usually can remove within 48-72 hours post insertion

What do you send the pleural fluid for?

Pleural Fluid Studies

Gram stain and culture

Antigen testing or Nucleic Acid Amplification testing by PCR

WBC and differential Helps to differentiate bacterial from fungal or

mycobacterial infection or malignancy

AFB

Analysis of pH, glucose, protein and LD Not likely to change management Not recommended

Antibiotic Therapy

If you have positive blood or pleural fluid cultures – tailor antibiotics appropriately

If blood and pleural fluid are culture negative – base antibiotic choice off of guidelines for CAP in hospitalized children

Treatment duration depends on adequacy of drainage and clinical response to therapy – usually 2-4 weeks

Some experts recommend 10 days post fever resolution

Antibiotic Therapy

S. Pneumoniae most commonly isolated pathogen in most studies

Staph Aureus – important cause of empyema but less common cause of uncomplicated CAP

More likely to get a positive blood culture in empyema caused by Staph Aureus than in S. Pneumoniae

Children Unresponsive to Treatment

Considered nonresponsive after 48-72 hours of initial therapy or with significant worsening any time during therapy

Estimated at between 5 and 15% of hospitalized patients

Children unresponsive to treatment

ImagingFor outpatients start with CXR If pleural effusion is suspected

Lateral decubitus x-ray Chest ultrasound

If chest mass, necrotizing pneumonia or chest abscess suspected CT chest

Children Unresponsive to Treatment

Consider drainage/VATS for effusions

Try to get a bugObtain pleural fluid samples in children who can

expectorateSend pleural fluid from drainage sampleTracheal aspirate or BAL for intubated patients

Consider expanding antibiotic coverage

Reassess for possible viral infection, mycobacterial or fungal infection

Children Unresponsive to Treatment

In children with underlying influenza infection who do not respond to oseltamivir – consider testing for oseltamivir resistance and use of alternate antiviral therapies (eg Zanamivir)

In children with initially confirmed viral CAP – consider secondary bacterial infection

Consider testing for atypical organisms and empiric coverage with a macrolide, tetracycline or fluoroquinolone

Pulmonary Abscess or Necrotizing Pneumonia in Nonresponding Patients

CT chest with contrast to confirm

Try to avoid surgical intervention – most will respond with antibiotics alone

For peripheral abscess with no airway communicationConsider CT guided drainage or catheter placement

Discharge Criteria

Decreasing fever

No supplemental oxygen (pulse oximetry > 90%)

Adequate oral intake

Free of intrathoracic leak for at least 12-24 hours post chest tube removal

Tolerating oral therapy

May want to observe patients with no surgical intervention longer for reaccumulation

Step down to Oral vs HPTP

When possible, conversion to oral step down is preferred to HPTP

No well defined criteria to identify patients requiring prolonged parenteral therapy

Required in patients requiring a high antibiotic concentration to achieve adequate exposure to effective tissuesParapneumonic effusionExtensive parenchymal diseaseLung abscess

Oral vs HPTP

No randomized control trials to demonstrate effectiveness of parenteral over oral therapy

Risk of catheter related complications

Reserve home parenteral therapy for patientsUnable to tolerate oral therapyWith pathogens that do not have appropriate oral

therapy

Prevention

Immunize,

immunize,

immunize!

Prevention

Immunize children against S. pneumoniae, H. influenzae type B and pertussis

Flu vaccine for all children > 6 months of ageDecreased incidence of pneumococcal CAP after

influenza infection

Parents and caregivers of infants < 6 months should be immunized against influenza and pertussis to avoid spreading disease

High risk infants should be vaccinated with RSV specific monoclonal antibody (Synagis)

Thanks!

Questions?

References

John S. Bradley et al. The Management of Community Acquired Pneumonia in Infants and Children Over 3 Months of Age: Clinical Practice Guidelines by the Pediatric Infectious Disease Society and the Infectious Diseases Society of America IDSA Guidelines. Clinical Infectious Diseases. August 2011.