Bronchial Atresia
Discussion
The patient's initial chest x-ray demonstrates a right upper lobe
hyperlucency and a corresponding opacity extending from the hilum
concerning for congenital bronchial atresia. CT imaging of the chest
confirmed the diagnosis, showing a right upper lobe cystic malformation;
bronchoscopy later showed an absence of the right upper lobe bronchus
and mucus impaction of the right lower lobe bronchus. Since her
symptoms were not overly bothersome and spirometry showed only a mild
obstructive pattern, the patient was initially managed conservatively
with bronchodilators and airway clearance protocol. However, over the
next six years, her dyspnea and sputum production persisted, and she
sought more definite therapy. Repeat pulmonary function testing was
significant for residual volume/total lung capacity ratio of 0.53,
significant for air trapping. She underwent bilobectomy through a video
assisted thoracoscopic approach. Intra-operative findings
interestingly showed not only a cystic malformation of the right upper
lobe and right upper lobe bronchial atresia, but also an absence of the
right middle lobe bronchus. Pathology was negative for malignancy.
Post-operatively, the patient's dyspnea resolved.
Congenital bronchial atresia is a rare congenital malformation
leading to early termination of affected bronchi but intact distal
parenchymal lung development. It is an uncommon condition with an
incidence of 1 case per 100,000 individuals. Mucus impaction,
bronchocele formation, lung hyperinflation through collateral
ventilation, and recurrent infections are possible pathophysiologic
sequelae of this disorder. This rare case of bilobar bronchial atresia
illustrates the diagnostic imaging findings on plain radiograph that are
highly suggestive of congenital bronchial atresia and should prompt
pursuit of confirmatory workup with CT imaging and/or bronchoscopy.
In addition to bronchial atresia, the differential diagnoses for
unilateral lung hyperlucency on chest radiograph includes: 1)
endobronchial obstruction via foreign body aspiration or tumor (which
was not consistent with the patient's history or further work up
including pathology); 2) Swyer-James Syndrome, a syndrome secondary to
childhood post-infectious bronchiolitis obliterans which can lead to
bronchiectasis and hypoplastic pulmonary arteries (not observed in this
case and patient denied childhood respiratory illnesses); 3) bullae (not
present on chest CT); and 4) pulmonary embolism, in which a large
thrombi results in oligemia to the affected lung (also not seen on chest
CT).
Most instances of congenital bronchial atresia are found
incidentally, and conservative management is pursued. However, this case
illustrates that a minority of patients require surgical intervention
to alleviate their symptoms, prevent complications, or exclude
underlying malignancy. Awareness of this diagnosis can avoid
potentially unnecessary surgical intervention in the majority of
bronchial atresia patients who are minimally symptomatic.
Thomas Wong, MD Internal Medicine Resident
Jigar Patel, MD Pulmonary Critical Care Fellow
Sara Swenson, MD, FACP
Randall Edson, MD, FACP, PD
California Pacific Medical Center
2351 Clay St.
Suite 360
San Francisco, CA, 94115
wongtj@sutterhealth.org | 808-255-5801
Resources
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Unique Approach to Diagnosing and Treating Congenital Bronchial Atresia
(CBA): A Case Series. J Pulm Respir Med. 2017; 7:402. doi:
10.4172/2161-105X.1000402
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Traibi A, Seguin-Givelet A, Grigoroiu M, Brian E, Gossot D.
Congenital bronchial atresia in adults: thoracoscopic resection. Journal
of Visualized Surgery. 2017;3:174. doi:10.21037/jovs.2017.10.15.
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Nemec S, Bakier A, Eisenberg R. Pulmonary Hyperlucency in Adults.
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10.2214/AJR.12.8917
