A 2 year old with fever and coughBMJ 2009; 339 doi: https://doi.org/10.1136/bmj.b2150 (Published 08 July 2009) Cite this as: BMJ 2009;339:b2150
All rapid responses
We thank Dr Mcknight for his interest in our picture quiz.
In this case, it is the lack of mediastinal shift towards the site of
the abnormality (or indeed other radiographic signs of lobar volume loss)
that is the important finding. The lack of such displacement would
indicate that the opacification in the right lung is not caused by
We agree that any ambiguity could have been avoided by using the
phrase “preservation of volume of the right hemi-thorax”.
The predominant abnormality on this radiograph is the lateral
density, tracking up the right lung, in keeping with a pleural effusion.
In apparent continuity with this, the density extends medially and is
likely in large part to be due to pleural fluid as well.
Traditional teaching is that in the presence of complete
opacification of a hemi-thorax due to a massive pleural effusion without
mediastinal shift, then the likely causes (in adults) are: 1) a central
bronchial occlusion causing concomitant lung collapse or 2) a mesothelioma
that has the effect of “freezing” the hemithorax. However, this
radiograph does not demonstrate complete opacification of the right hemi-
thorax, and the absence of mediastinal shift away from the effusion, does
not exclude the presence of a large right loculated effusion, without
collapse . Indeed, how much loculated pleural fluid (adjusting for
adjacent compressive atelectasis that is often seen in an empyema) is
required to cause mediastinal shift visible on a chest radiograph in a 2
year old is unknown.
Compressive atelectasis is often seen adjacent to an empyema, and
this may be present in this case. However, the extent of such atelectasis
cannot be judged based on the radiograph.
We would like to reiterate that there are no air bronchograms (ie air
filled bronchi within high attenuation lung ) on this radiograph. While
the absence of air bronchograms does of course not exclude consolidation,
it is another observation that suggests that the extensive opacification
in the right lung is not predominantly due to consolidation.
Ultimately, ultrasound is the next imaging test of choice. Amongst
other uses, it has the ability to more accurately quantify the extent of
pleural fluid, versus collapsed or consolidated lung . In this case,
ultrasound showed the presence of a large right loculated effusion, which
was further confirmed by the drainage of 1 litre of pus from the right
1. Swishchuk LE. Imaging of the newborn, infant, and young child.
6th ed. 2006. Lippincott Williams & Wilkins. p. 112.
2. Hansell DM, Bankier AA, MacMahon H, McLoud TC, Muller NL, Remy J.
Fleischner Society: glossary of terms for thoracic imaging. Radiology
3. Balfour-Lynn IM, Abrahamson E, Cohen G, et al. BTS guidelines for
the management of pleural infection in children. Thorax 2005; 60 Suppl
Competing interests: No competing interests
The authors state "The chest radiograph shows near complete
opacification of the right hemithorax, with preservation of lung volumes
and absence of air bronchograms". There are important errors in their
The radiograph shows collapse and consolidation in the right
lung. There is a pleural effusion and there is not preservation of lung
volumes. Their correct observation that the mediastinum is central shows
that there must be loss of volume in the lung as there is a pleural
effusion. If the lung volume is preserved and a pleural effusion is
present then the mediastinum shifts away from the abnormality. If the lung
collapses and there is no pleural effusion then the mediastinum shifts
towards the abnormality. When the mediastimun is central and there is a
pleural effusion then there must be loss of volume in the lung. There is
air present in the right lung and there must be considerable consolidation
in the right lung. The expression air bronchogram can be confusing. It
refers to air in major bronchi and fluid in the smaller airways such as
alveoli and terminal bronchioles. The bronchi stand out as they are filled
with air and consolidation in the lung opacifies the radiograph. I suspect
there is extensive consolidation here but the pleural effusion makes it
difficult to see these abnormalities.
I am not sure if this case was
externally reviewed but it is important to correct the significant errors
Competing interests: No competing interests