Chronic Lung Sepsis

1
Chronic Lung Sepsis

• Dr. Arun Nair

2
Includes

• Lung Abscess
• Empyema
• Bronchiectasis

3
Lung Abscess
4
(No Transcript)
5
Lung Abscess

6
Definition overview

• Cavitating, infected, necrotic lesion of lung
  parenchyma
• Several possible causes
• Single or Multiple
• Small lt2cm or large
• Most secondary to aspiration of oropharyngeal
  secretions
• Mixed growth of organisms, including anaerobes

7
Causes

• Aspiration
• Bronchial obstruction Tumour / Foreign Body
• Pneumonia
• Blood borne infection
• Transdiaphragmatic spread

8
Differential Diagnosis

• Cavitating tumour
• Infected bronchial cyst/bulla
• Localised saccular bronchiectasis
• Aspergilloma
• Wegeners granulomatosis
• Hydatid cyst
• Gas-fluid level in oesophagus, stomach or bowel

9
Microbiology

• Anaerobes Peptostreptococcus, Prevotella,
  Bacteroides spp (usually not B. fragilis), and
  Fusobacterium spp.
• Staph Aureus, Klebsiella, Strep Milleri
• Strep Pneumonia, gram negative bacilli
• M.Tuberculosis
• Fungi

10
Clinical Features

• Most patients present over several weeks
• Malaise, weight loss, fever
• Cough with copious purulent sputum
• Can be associated with haemoptysis
• Toxic features prominent in patients with
  pneumonia or blood borne infection
• Clubbing often seen

11
Investigations

• CXR PA Lateral
• CT Thorax
• Sputum Blood Cultures
• FBC, CRP, ESR, Serological tests

12
Treatment

• AUGMENTIN
• AMOXIXCILLIN METRONIDAZOLE
• CLINDAMYCIN
• Physiotherapy postural drainage
• Trans Thoracic/ endoscopic drainage for large
  abscess
• Duration of ABx
• 3- 4 weeks

13
Empyema

• Pus in pleural space
• Sequelae of a complicated parapneumonic
  infection, when bacteria invade pleural space
• Uncomplicated
• Complicated
• Frank Empyema

14
Pathogenesis

• Uncomplicated parapneumonic effusion  
• occurs when the lung interstitial fluid increases
  during pneumonia, and is characterized by
  "exudative" pleural fluid chemistries and an
  influx of neutrophils into the pleural space.
• resolve with resolution of the pneumonia.

15
Complicated Parapneumonic effusion

• occurs when there is persistent bacterial
  invasion of the pleural space.
• Results in pleural fluid acidosis (anaerobic
  utilization). Lysis of neutrophils increases the
  LDH concentration in the pleural fluid to values
  often in excess of 1000 IU/L.
• Complicated parapneumonic effusions are often
  sterile because bacteria can be cleared rapidly
  from the pleural space. (Loculation )

16
Thoracic Empyema

• Formation of empyema is the third stage and is
  characterized by bacterial organisms seen on gram
  stain or the aspiration of pus on thoracentesis.
• A positive culture is not required for diagnosis.

17
Bacteriology

• Mixed bacterial flora
• Anaerobic bacteria in 36-76
• Streptococcus milleri, Staphylococcus aureus, and
  Enterobacteriaceae.
• Patients with diabetes mellitus are at increased
  risk of empyema secondary to Klebsiella
  pneumoniae.
• S. pneumoniae and S. aureus (including
  methicillin-resistant organisms) are the leading
  causative bacteria in children with empyema.

18
Pleural fluid analysis

• Pus
• Ph lt7.2
• Glucose lt 60 mg/dl
• LDHgt1000 IU/L
• WBCgt15/nl

19
Imaging

• CXR
• CT
• USG

20
Signs favouring empyema

• Evidence of lung compression
• Smooth margins
• Blunt angle with chest wall
• Dissection of thickened visceral and parietal
  pleura

21
Treatment

• Pleural drainage
• Chest Drain
• Thoracoscopy
• Antibiotics
• Fibrinolytics No convincing benefit

22
Bronchiectasis

• Abnormal permanent dilatation of one or more
  bronchi
• Poor mucous clearance
• Chronic bacterial infection inflammation
• Long term lung damage

23
Types

• Saccular /Cystic
• Cylindrical
• Varicose

24
Saccular Bronchiectasis

• Large baloon like dilatation from severe loss of
  bronchial wall
• Assoc with severe lung infections, large sputum
  volumes, finger clubbing

25
Cylindrical Bronchiectasis
26
Varicose Bronchiectasis
27
Causes

• Congenital defective bronch wall/
  sequesteration
• Post infective TB, Pertussis, NTM, ABPA
• Airway obstruction (eg, foreign body aspiration)
• Defective host defenses CVID, HIV, phagaocyte
  dysfn
• Inflammatory pneumonitis gastric aspiration,
  toxic gas inhalation
• Abnormal mucociliary clearance Primary Ciliary
  Dyskinesia, cystic fibrosis, Young's syndrome
• Rheumatic and systemic diseases, cigarette
  smoking, Chronic Bronchitis.

28
Symptoms

• Cough (98 percent of patients)
• Daily sputum production (78 percent)
• Dyspnoea (62 percent),
• Rhinosinusitis (73 percent)
• Hemoptysis (27 percent)
• and recurrent pleurisy (20 percent).

29
Physical Findings

• Crackles (75 percent)
• Wheezing (22 percent) were common,
• Digital clubbing occurred in only 2 percent of
  patients.

30
Pathophysiology

• Induction of bronchiectasis requires two factors
• An infectious insult
• Impaired drainage, airway obstruction, or a
  defect in host defense
• Recurrent infection leads to further scarring,
  obstruction, and distortion of the airways, as
  well as temporary or permanent damage to the lung
  parenchyma.

31
Diagnostic workup

• The following LAB studies should be part of the
  initial evaluation of a patient with
  bronchiectasis
• A complete blood count with differential
• Immunoglobulin quantitation to measure the levels
  of the immunoglobulins IgG, IgM, and IgA
• Sputum culture and smear for bacteria,
  mycobacteria, and fungi

32
Imaging

• CXR radiographic findings include linear
  atelectasis, dilated and thickened airways (ie,
  tram or parallel lines, ring shadows on cross
  section) and irregular peripheral opacities that
  may represent mucopurulent plugs.

33
High Resolution CT Thorax

• Airway dilatation
• Bronchial wall thickening
• Lack of tapering
• mucopurulent plugs or debris accompanied by
  post-obstructive air trapping (tree-in-bud)

34
Distribution

• A central (perihilar) distribution is suggestive
  of ABPA.
• predominant upper lobe distribution is
  characteristic of cystic fibrosis
• middle and lower lobe distribution is consistent
  with PCD
• lower lobe involvement is typical of idiopathic
  bronchiectasi

35
Spirometry

• Obstructive picture common
• Frequently isolated pathogens on CULTURE include
  Hemophilus influenzae, Pseudomonas aeruginosa
  (especially mucoid types), and, less frequently,
  Streptococcus pneumoniae

36
Treatment

• Postural drainage
• Based on sputum culture sensitivity
• Non-Pseudomonas organism
• Amoxicillin 1gm TID 14 days
• Augmentin 625 mg TID 14 days
• Doxycyline 100mg BD 14 days
• Ciprofloxacin 750 mg BD 14 days (Pseudomonas)
• Ceftazidime 2gm TID 7-14 days (Pseudomonas)
• Nebulised Tobramycin (Pseudomonas)

37
END
38
Signs favouring lung abscess

• Spherical shape with irregular and thick wall
• Absence of lung compression
• Sharp angle with chest wall
• Vasculature around abscess