ATYPICAL PNEUMONIAS: THE BASICS

1
ATYPICAL PNEUMONIAS THE BASICS

• Nilesh Patel, DO
• October 8, 2008
• St. Josephs Regional Medical Center

2
QUESTIONS WE WILL ANSWER???

• What is an atypical pneumonia?
• What are the organisms that compromise atypical
  pneumonias?
• How do we test for atypical pneumonias does it
  matter?
• What are the antibiotic choices?
• What should we think about when HIV patients
  present with pneumonia?

3
OBJECTIVES

• We will discuss.
• Mycoplasma pneumoniae
• Legionella sp.
• Chlamydia pneumoniae
• Chlamydia psittaci
• Viral pneumonias
• Pneumonia in the setting of HIV/AIDS--PCP

4
ATYPICAL PNEUMONIA WHAT IS IT???

• Infection of pulmonary parenchyma
• Community-acquired
• Classicallydo not show up on Gram stain
• Characteristics
• Atypical presentation/symptoms/diagnostics
• Insidious onset
• Nonproductive cough
• Constitutional symptoms
• Interstitial pattern on CXR
• Smoldering course
• The lines are blurred
• Similar to typical organisms clinically and
  radiographically

5
ORGANISMS

• Mycoplasma pneumonia
• Viral pneumonias
• RSV
• Parainfluenza
• Adenovirus
• Influenza
• Other
• Chlamydia pneumonia
• Chlamydia psittaci
• Legionella pneumophila
• Coxiella burnetti (Q fever pneumonia)
• Francisella tularensis (Tularemia)

6
EPIDEMIOLOGY

• 4 million cases CAP/year
• 20-60 typical organisms
• 10-40 atypical organisms
• Hard to quantify these organisms

7
PATHOPHYSIOLOGY
8
MYCOPLASMA PNEUMONIA

• Smallest free living organisms
• Prokaryotes
• No cell wall
• Most common cause of atypical pneumonia
• Walking pneumonia
• Community acquired
• Usually occur in young to middle aged patient
• Clinical symptoms
• Insidious onset, protracted course
• Constitutional symptoms (fevers, chills,
  myalgias, body aches)
• Sore throat, HA
• Dry cough
• Chest pain/SOB

9
MYCOPLASMA DIAGNOSTICS

• CXR
• Consolidation
• Patchy infiltrates
• Interstitial pattern
• Pleural effusion
• Labs
• WBC
• Cold agglutinin assays
• Other serum assays
• Cultures
• Blood
• Sputum

10
(No Transcript)
11
(No Transcript)
12
MYCOPLASMA TMT

• Macrolides
• Azithromycin
• Erythromycin
• Clarithromycin
• Doxycycline

13
LEGIONELLA

• Gram negative intracellular rods
• Fastidious
• Multiple serotypes
• Legionella pneumophila
• Community acquired
• Legionnaires disease
• Transmission from contaminated water sources
• Warm water environments
• No person to person transmission
• Outbreaks.Sporadic cases
• High mortality if not treated

14
LEGIONELLA

• Natural water habitats
• Water distribution systems
• Cooling towers
• Hot tubs/Spas
• Respiratory equipment
• Humidifiers
• Etc
• Travel
• Hotels
• Large Events
• Floods/Natural Disasters

15
LEGIONELLA SYMPTOMS

• Incubation period 2-10 days
• Clinical symptoms
• Pulmonary
• Cough
• Chest pain
• Dyspnea
• Extrap-pulmonary
• Constitutional symptoms
• GI symptomsdiarrhea, abd pain, n/v
• Neuro symptomsHA, change in mental status

16
LEGIONELLA DIAGNOSTICS

• CXRvariable
• Consolidation
• Patchy infiltrates/Interstitial infiltrates
• Pleural effusions
• Multi-lobar
• Labs
• CBC, SMA-7 (Hyponatremia, Elevated LFTs, ARF)
• CPK
• Urine antigen tests
• Serum legionella antibodies
• PCR
• Cultures
• Sputum gram stain/culture DFA sputum
• Blood cultures

17
(No Transcript)
18
LEGIONELLA TMTS

• Fluoroquinolones
• Levaquin
• Avelox
• Macrolides
• Zithromax
• Doxycycline
• Bactrim
• Rifampin
• Extended course
• Initial IV therapy

19
CHLAMYDIA

• Chlamydia 3 sp (pneumoniae, psittaci,
  trachomatis)
• Gram negative obligate intracellular organisms
  (parasites)
• Unique organisms
• Community acquired
• Chlaymydia pneumoniae
• Common
• Respiratory transmission (person to person)
• Pneumonia
• Chlaymdia psittaci
• Rare
• Ornithosis
• Respiratory transmission (infected birds to
  humans)
• Pneumonia/Viral illness

20
CHLAMYDIA PNEUMONIA

• Clinical symptoms
• Incubation period 1-4 weeks
• Acute/subacute illness
• Self limited URI/bronchitis
• Fever
• Constitutional symptoms
• Cough
• Chest pain/sob
• Pharyngitis
• Sinusitis
• Rales/Rhonchi/Wheezing

21
CHLAYMDIA PSITACCI

• Risk FactorsContact with birds
• Clinical symptoms (incubation 5-30 days)
• Acute viral illness/flu like symptoms
• Fever
• Relative bradycardia
• Constitutional symptoms
• Chest pain/sob
• Multi-system
• Neuro symptomsHA, altered mental status
• HSM (elevated LFTs)
• RashHorder spots, EM, EN
• Rales/Rhonchi/Wheezing/Clear lungs

22
CHLAMYDIA DIAGNOSTICS

• Chlamydia pneumonia
• CXR
• Cultures
• Serologic tests
• Chlamydia psitacci
• CXR
• Cultures
• Serologic tests

23
(No Transcript)
24
CHLAMYDIA TMTS

• Chlamydia pneumoniae
• Doxycycline/Tetracycline
• Macrolides (Zithromax, Clarithromycin, E-mycin)
• Quinolones (Avelox, Levaquin)
• Chlamydia psitacci
• Doxycycline/Tetracycline
• Macrolides (Zithromax, E-mycin)

25
VIRAL PNEUMONIAS

• More common in pediatric population and elderly
• Up to 15 of all CAP cases
• MildgtgtgtgtSevere
• Influenza A B
• RSV
• Adenoviruses
• Parainfluenza
• SARS
• Avian flu
• Varicella
• CMV
• Herpes virus
• Hanta virus

26
ANTIBIOTICS

• Outpatient/Inpatient/ICU
• Remember coverage for CAP
• MycoplasmaMacrolide, Doxy
• LegionellaQuinolone, Macrolide
• Chlaymydia pneumoniaDoxy, Macrolide
• Chlaymida psitacciDoxy, Macrolide
• Viral pneumonias
• Supportive care
• InfluenzaTamiflu, think Staph coverage

27
HIV PNEUMONIA

• Most common infectious process in HIV patients
• Broaden differential diagnosis
• CD4 count viral load important for specific
  organisms and prognosis
• CAP most common
• Other
• PCP
• TB
• MAC
• Histoplasmosis/Coccidiomycosis
• Viral pneumonias

28
PCP

• Pneumocystis carinii gtgt Pneumocystis jiroveci
• Unicellular fungus
• Various morphology--cysts
• Pre-HIVfew cases
• Most common opportunistic infection in HIV
  patients
• Common cause of death in HIV patients mortality
  15
• Decreased incidence with prophylaxis and
  antiretroviral treatment
• Transmissionhuman to human airborne
• Pneumocystis is widespread
• Symptomatic disease occurs in immunosuppressed
  populations

29
PCP CLINICAL SYMPTOMS

• Symptoms
• SOB (exertional)
• Cough
• Fevers
• Constitutional symptoms
• Chest pain
• Signs
• Tachypnea/Fever/Tachycardia
• Rales/RhonchiWheezing
• Cachexia
• Lymphadenopathy
• Cyanosis

30
PCP DIAGNOSTICS

• Labs
• CBC, SMA-7
• LDH
• ABG
• Imaging
• CXRvariable
• NormalgtgtDiffuse b/l infiltratesgtgtPerihilar
  infiltratesgtgtPTX
• CT scan
• Diffuse b/l infiltratesgtgtGround glass
  appearancegtgtCysts
• Sputum culture
• BAL
• ComplicationPTX!

31
(No Transcript)
32
(No Transcript)
33
(No Transcript)
34
(No Transcript)
35
(No Transcript)
36
PCP TMT

• Supportive treatments
• Oxygen
• Noninvasive/Invasive ventilation
• Antibiotics (14-21 days or until clinical
  response achieved)
• Bactrim IV
• Pentamadine IV or aerosolized
• Atovaquone po
• Other therapies
• SteroidsHypoxemia, PaO2 lt 70, Severe disease
• Prophylaxis

37
PCP COMPLICATIONS

• Hypoxemic respiratory failure
• ARDS
• PTX
• Risk for other opportunistic infections

38
SUMMARY

• Atypical pneumonias
• Mycoplasma
• Legionella
• Chlamydia
• Viral pneumonias
• HIV pneumonia
• PCP