Fig 5. CXR on follow-up showing re-expansion of the right lung
Pulmonary pseudocysts are often a sequela of blunt trauma to the chest
wall, although cases following penetrating injuries to the chest have
also been described. (1) Traumatic pulmonary
pseudocysts often occur within 24 hours after the injury, may be single
or multiple and are usually self-limiting with an excellent prognosis.(2) Multiple pseudocysts not related to trauma have
been reported in neonates with hyaline membrane disease on mechanical
ventilation. (3) Pseudocysts with predominant
inflammatory processes are usually multiple, small and have been
described in smokers, asthmatics and in cystic fibrosis patients.(4). Some authors have lumped pseudocysts with
congenital cystic lung lesions under a broader group of cystic and
pseudocystic pulmonary malformations. (CPPM) (5) Most
CPPM lesions disappear in utero and are generally asymptomatic but may
be responsible for fetal death, early life respiratory distress,
recurrent pulmonary infections, or can transform to malignant lesions.(5) It is challenging to make a distinction between
cystic and pseudocystic pulmonary lesions radiologically, on chest
radiography or HRCT. Definitive diagnosis of a pseudocyst is only
possible histopathologically, where the absence of epithelial cells or
lung tissue is diagnostic of a pseudocyst. The management of congenital
pulmonary airway malformation in asymptomatic children is controversial,
some adopt a wait-and- see approach while others prefer a more
aggressive approach of surgical excision to avert the risk for malignant
transformation. In symptomatic patients, it is prudent to excise the
cyst to achieve symptom relief.
- Gulbahar G. Diagnosing traumatic pulmonary pseudocyst. South Med J.
2009; 102(9):881. doi : 10.1097/SMJ.0b013e3181b187d3.
- Kanj A, Tabaja H, Soubani AO, Kanj N. Traumatic Pulmonary Pseudocyst
Mimicking a Congenital Cystic Lung Disease. Case reports in
pulmonology. 2018; 2018:7269694.doi : 10.1155/2018/7269694
- Harris H. Pulmonary pseudocysts in the newborn infant. Pediatrics.
1977; 59(2):199-204. doi : 10.1136/adc.58.8.612.
- Tomashefski JF Jr, Bruce M, Stern RC, Dearborn DG, Dahms B. Pulmonary
air cysts in cystic fibrosis: relation of pathologic features to
radiologic findings and history of pneumothorax. Hum Pathol 1985; 16:
253-261.doi: 10.1016/s0046-8177(85)80011-3
- Rodríguez-Velasco A, López-Jara-Zárate EJ, Vargas MH, Ramírez-Figueroa
JL, Furuya ME. Cystic and pseudocystic pulmonary malformations in
children: Clinico-pathological correlation. Ann Diagn Pathol. 2019;
39:78-85. doi :
10.1016/j.anndiagpath.2019.02.005