230 The Potentially Lethal Nature of Bronchial Casts: Plastic Bronchitis Mariana M. Cajaiba, MD, Paula Borralho, MD, and Miguel Reyes-Múgica, MD bronchoscopy was performed, resulting in the removal of multiple bronchial casts. Despite respira- tory support, there was no improvement in systemic perfusion; the patient’s status deteriorated, and he expired 5 days after admission to the hospital. His past medical history was remarkable for tricuspid atresia, treated at the age of 4 with a Fontan proce- dure (diversion of systemic venous return into pul- monary circulation). Six months before his last hospital admission, he underwent surgical review of the previous procedure, in which the right atrium was excluded with the creation of an external con- duit using grafted material. Two bronchial casts removed by bronchoscopy were submitted for histological examination. Macroscopically, they appeared as mucoid white- yellow bronchial-like structures measuring 6.5 and 8.0 cm, respectively (Figure 1A). On light microscopy, it was seen that the casts were composed predomi- nantly of mucin, as demonstrated by PAS and Alcian-blue stains, intermixed with fibrin and a few leucocytes (Figure 1B). An autopsy was performed, which revealed the cardiac anatomical changes derived from the above-mentioned procedures, in addition to severe diffuse alveolar damage and changes suggestive of acute hypoxemia. P lastic bronchitis (PB) is an uncommon disorder characterized by the formation of extensive bronchial casts that branch into the respira- tory tree, adopting its 3-dimensional architecture and occluding it. These casts differ from those formed by ordinary mucus, being larger, more cohe- sive, and with a gelatinous, rubbery, or rigid consis- tency. The definitive diagnosis can only be made through examination of the casts, which are usually removed through bronchoscopy but may also be expectorated. 1,2 Case Reports Case 1 A 16-year-old male presented with sudden onset of dyspnea, tachycardia, and hypoxemia, for which a The gross and microscopic findings from 2 fatal cases of plastic bronchitis (PB) in children, a rare entity characterized by the formation of large mucous casts in the bronchial tree, are presented. These casts differ from ordinary mucus because of their increased cohe- siveness and consistency, resulting in solid structures that model the respiratory airway tree. PB usually pres- ents as a complication of underlying diseases, which determine the prognosis of the afflicted patients. Conditions commonly associated with PB include con- genital cardiopathies, lymph vessel malformations, asthma, and sickle cell disease. The first case is a typ- ical example of PB following surgical treatment of a cyanotic cardiopathy, with very characteristic and illus- trative morphology. The second case describes the fatal course of PB in a patient with sickle cell disease, which has never been reported to the best of the authors’ knowledge; in this case, an overlooked association with asthma could have contributed to the fatal outcome. Keywords: plastic bronchitis; bronchial casts; sickle cell disease; cyanotic cardiopathy From the Departments of Pathology (MMC, MRM) and Pediatrics (MRM), Yale University School of Medicine, New Haven, Connecticut, and the Department of Pathology, Hospital Garcia de Orta, Almada, Portugal (PB). Address correspondence to: Miguel Reyes-Múgica, Program of Pediatric and Developmental Pathology, Yale University School of Medicine, 430 Congress Avenue, New Haven, CT 06520; e-mail: miguel.reyes@yale.edu. International Journal of Surgical Pathology Volume 16 Number 2 April 2008 230-232 © 2008 Sage Publications 10.1177/1066896907307234 http://ijsp.sagepub.com hosted at http://online.sagepub.com by guest on April 8, 2016 ijs.sagepub.com Downloaded from