Case Presentation:

A 41–year–old Caucasian male with past medical history significant for morbid obesity, OSA and two recent admissions for pneumonia presented with dyspnea and expectoration of brownish yellow “sea creatures” for 2 weeks. Patient completed two 14 days courses of antibiotics for pneumonia over prior 3 months. Review of systems was remarkable for bilateral lower extremity edema and subjective fevers but no recorded fever. Social and family histories were noncontributory. CT scan chest was significant for bilateral patchy lower lobes pneumonia slightly improved from previous admissions. Laboratory investigations including BNP, CBC, LFT were unremarkable. Bronchoscopy revealed yellowish rubbery bronchial casts outlining bronchial anatomy and the diagnosis of plastic bronchitis was made. Cast pathology and bronchial washings revealed mucus, neutrophils, macrophages and cryptococcus neoformans. Regular aerobic blood cultures grew rare cryptococcus neoformans. Patient was started on induction therapy with Amphotericin B and Flucytosine for possible cryptococcis. Serum cryptococcal antigen was weakly positive though fungal isolator cultures were negative. Further laboratory tests for identifying the underlying pathology viz. Lumbar punture CSF, HIV, CFTR gene, aspergillus antibody, alpha 1 antitrypsin, immunity testing and AFB were unremarkable. ECHO and PFTs were normal. In absence of CNS involvement, he was switched over to 6 months of fluconazole with improvement in symptoms over next few weeks. When last followed up 8 months after the initial onset of symptoms patient did not have overt bronchial casts expectoration though still had bouts of dysnpea and liquidy brownish expectoration.

Discussion:

Plastic bronchitis (PB) is an uncommon entity characterized by recurrent expectoration of large, branching bronchial casts. Etiology of PB is obscure though it is associated with diffuse bronchial hypersecretory disorders– mucoid impaction, asthma, ABPA, mucoviscidosis, pneumonia, pericardial effusion, sickle cell disease and heart failure. The treatment includes acute therapy to facilitate removal and expectoration of casts– n–acetylcysteine, steroids and long term to treat underlying hypersecretory process. Therapeutic options lack strong evidence as they are based on case reports confounding systematic investigations of its treatment. Interestingly in this patient, the cause of plastic bronchitis could not be established with confidence. However, improvement with anti fungals do indicate that cryptococcal infection might have had causal relationship rather than just being an incidental finding. Cryptococcal association with plastic bronchitis has not been reported previously and is reported here for the first time.

Conclusions:

Plastic bronchitis remains an under recognised entity that warrants awareness among the healthcare providers. Cryptococcal infection can be associated with PB and should be kept as a differential while working up PB.