La sindrome del lobo medio

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Azienda Ospedaliero-Universitaria Ospedali
Riuniti - Ancona Ospedale Pediatrico di Alta
Specializzazione G. Salesi Dipartimento di
Pediatria
La sindrome del lobo medio fernando maria de
benedictis
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Editorial Respecting the Middle Lobe
Syndrome Rubin, Pediatr Pulmonol 200641803
I have not given the middle lobe syndrome
a great deal of respect .
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Middle Lobe Syndrome whats in the name ?
The middle lobe syndrome in children is
characterized by a spectrum of clinical and
radiographic presentations, from persistent to
recurrent atelectasis to pneumonitis and
bronchiectasis of the right middle lobe and/or
lingula
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Middle Lobe Syndrome a 70-year-old story

• Brock, 1937 First description of MLS
• 
  (secondary to TB adenopathy)
• 
  
  
  
  
  
  
  
  
  
• Graham, 1948 First non-TB cases
• Paulson, 1949 Description of anatomy of RML
  bronchus
• 
  
  
  
• Harper, 1950 Description of involvement of
  lingula
• Bradam, 1966 Role of chronic infection of RML
• Culiner, 1966 Role of poor collateral
  ventilation of RML
• Danielson, 1967 Description of familiar cases

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Middle Lobe Syndrome Predisposing factors (1)

• Characteristics of RML
• Compressed between RUL and RLL
• Relative anatomic isolation
• Poor collateral ventilation
• (incomplete development pores of
• Kohn and channels of Lambert in
• in early childhood)

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Middle Lobe Syndrome Predisposing factors (2)

• Characteristics of RML bronchus
• Acute take-off angle
• Narrow diameter
• Soft bronchial wall
• Surrounded by many lymphnodes

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Middle Lobe Syndrome Causes
Obstructive - intrabronchial (foreign body,
mucosal edema, mucus plugs, bronchial
stenosis, bronchiectasis, tumor) -
extrabronchial (lymphnodes, tumor,
cardiomegaly) Non-obstructive
Inflammation, infection
The mechanisms may be interactive
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Obstructive type of MLS Pathophysiology

• Intraluminal/extraluminal
• obstruction

Isolated lobe / segment
Blood absorption of trapped gas
Atelectasis
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Non-obstructive type of MLS Pathophysiology

• Infection / inflammation

Usually partial obstruction due to edema and/or
mucous plugging
Difficulty of the lobe to re-expand
Recurrent pneumonia,bronchiectasis, fibrosis
Atelectasis
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Middle Lobe Syndrome Underlying conditions
Asthma
Always consider associated conditions
Primary ciliary dyskinesia
Cystic fibrosis
Immunological disorders
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Middle Lobe Syndrome Clinical findings
55 children with MLS, mean age 5.5 yrs - Asthma,
CF, PCD, Immunodeficit excluded Mean duration of
symptoms 14.5 months Mean follow-up for 24
months
100
In half of the population, MLS were unnoticed,
although symptoms persisted for many months
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65
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Priftis, Chest 20051282504
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Middle lobe syndrome in children with
asthma Sekerel, J Asthma 200441411
56/3528 (1,6) asthmatic children with MLS, mean
age 6.2 yrs, mean duration of symptoms 22 days,
mean follow-up 3.6 yrs

Persistent asthma symptoms and/or sputum
production should alert the physician to
complicating MLS !!!

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22 days
8
8 days
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The role of timely chest radiograph in diagnosing
middle lobe syndrome
Chest X-ray, please ! ?
Any postponement in obtaining a chest radiograph
in a patient with non-specific, often mild,
persistent respiratory symptoms may result in
failure to diagnose longstanding MLS
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Middle Lobe Syndrome Diagnostic tools (1)

• Chest radiograph
• Blurred right heart border and loss of volume of
  the RML on P-A view
• Wedge-shaped density extending from the hilum on
  L-L view
• RML collapse secondary to hyperinflation of
  adjacent lobes on P-A view

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Diagnosing middle lobe syndrome in the real life
63 episodes of MLS in asthmatic children with
MLS, mean duration of symptoms 22 days
Only a minority of previously undiagnosed cases
had been evaluated with lateral radiograph !
28/28 (100)
43/63 (68)
5/63 (8)
Sekerel, J Asthma 200441411
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How can we differentiate atelectasis from lobar
consolidation of RML ?
Atelectasis Consolidation
Lung volume loss - Not significant
Compensatory emphysema - --
Mediastinum shift Toward lesion --
Diaphragm position Unilateral elevated Not significant
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Middle lobe syndrome Diagnostic tools (2)

• HRCT scan
• Extension and characteristics
• of parenchymal damage
• Bronchiectasis
• Patency of RML bronchus
• Mediastinal lymph nodes

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The role of timely intervention in middle lobe
syndrome in children Priftis, Chest 20051282504
55 children with MLS - Duration of symptoms
before presentation from 3 to 48 months HRCT scan
performed after an aggressive medical treatment
There was a positive correlation between the
duration of symptoms and the development of
bronchiectasis
55 pts
40/75 (73)
15/55 (27)
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The role of timely intervention in middle lobe
syndrome in children Priftis, Chest 20051282504
55 children with MLS, median age 5,5
yrs Aggressive timely intervention Follow-up
for 24 months

There was a clear association between the
presence of bronchiectasis and an unfavorable
clinical and radiographic outcome
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Middle lobe syndrome Diagnostic tools (3)

• Fibroptic bronchoscopy
• Patency of the RML bronchus
• BAL cells profile and microbiology
• Biopsy

FOB has been recognized as a useful and safe
tool in the investigation of infants and children
with airway diseases, including persistent
atelectasis Midulla, ERS Task Force ERJ
200322698
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The role of timely intervention in middle lobe
syndrome in children
55 children with MLS, median age 5,5
yrs Bronchoscopy and BAL after radiographyc
diagnosis
Over half of the patients have an underlying
bacterial infection, although none had clinically
diagnosed pneumonia
MLS is strengthly associated with asthma, and
chronic inflammation of the lung is present in
more than half of population
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36
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9
12
10
3
3
3
3
3
Fungi
S aureus
Normal
Neutrophil
H Influenzae
Eosinophil
M catarrhalis
P aeruginosa
Lynphocyte
Mucobacteria
S Pneumoniae
Macrophages
Microbiology
BAL fluid cellular components
Priftis, Chest 20051282504
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Middle lobe syndrome Management

• Conservative treatment
• Antibiotics
• Chest physiotherapy and postural drainage
• Inhaled bronchodilators
• Inhaled corticosteroids
• Systemic corticosteroids
• Mucolytics

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Middle Lobe Syndrome Invasive - Surgical
management

• 1st step Bronchoscopy
• Removal of foreign bodies, retained
  secretions, tumor
• 2nd step Surgical resection
• recurrent atelectasis or failure of RML to
  re-expand
• after conservative therapy and bronchoscopy
• presence of severe bronchiectasis
• extensive infection / destruction of a lobe or
  segment
• refractory to medical therapy

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Middle lobe syndrome Outcome

• Usually favourable with conservative treatment
• Bronchoscopy may be resolutive
• Surgery is rarely required

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Outcome after right middle lobe syndrome in
children De Boeck, Chest 1995108150
17 children, mean age at diagnosis 3.3 yrs, mean
interval follow-up 6.2 yrs

PFT and PD20 MCH were significantly lower in
patients with ongoing respiratory symptoms

• 14/17 had repeated episodes
• of RML collapse
• 5/17 had further respiratory
• symptoms

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40
12
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Middle Lobe Syndrome what should we remember ?
1- It is a well defined clinical/radiographic
entity
2- Do not trust on physical examination alone
3- In case of suspect, consider timely and
complete chest radiograph
4- In case of long duration of clinical history,
HRCT is mandatory
5- An aggressive, rational, multidisciplinary
intervention is often resolutive
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Editorial Respecting the Middle Lobe
Syndrome Rubin, Pediatr Pulmonol 200641803
.middle lobe syndrome deserves our respect