Categories
BLOG

cystic fibrosis and marijuana

“Bong lung” in cystic fibrosis: a case report

Zoe Gao

1 Departments of Respiratory Medicine, Royal Hobart Hospital, Liverpool Street, Hobart, Tasmania, 7000, Australia

Richard Wood-Baker

1 Departments of Respiratory Medicine, Royal Hobart Hospital, Liverpool Street, Hobart, Tasmania, 7000, Australia

Robin Harle

2 Radiology, Royal Hobart Hospital, Liverpool Street, Hobart, Tasmania, 7000, Australia

Kon Muller

3 Discipline of Pathology, University of Tasmania Medical School, Collins Street, Hobart, Tasmania, 7000, Australia

Jenny Hauser

1 Departments of Respiratory Medicine, Royal Hobart Hospital, Liverpool Street, Hobart, Tasmania, 7000, Australia

David W Reid

1 Departments of Respiratory Medicine, Royal Hobart Hospital, Liverpool Street, Hobart, Tasmania, 7000, Australia

Abstract

Introduction

Marijuana or “bong” lung has been recently described. Subjects typically develop large peripheral paraseptal lung bullae and are predisposed to spontaneous pneumothoraces. The underlying mechanism for bullae formation is uncertain, but probably relates to direct lung toxicity and repeated barotrauma as the smoker performs frequent valsalva manoeuvres in an attempt to derive a greater drug effect.

Case presentation

We describe a case of probable “bong lung” occurring in a 23-year-old Caucasian man with cystic fibrosis who had a history of recurrent pneumothoraces and unusual findings on sputum cytology.

Conclusion

Our case highlights the importance of questioning young adult cystic fibrosis patients about illicit drug use and the utility of sputum cytology and computed tomography scanning when patients present with pneumothoraces and deteriorations in clinical status.

Introduction

Marijuana smoking has recently been identified as a risk factor for bullous lung disease and the occurrence of recurrent pneumothoraces [1,2]. Upper lobe lung deposition of hot particulate matter following inhalation stimulates an inflammatory response that is characterised by the accumulation of carbon-laden alveolar macrophages (AM) and polymorphonuclear cells (PMNs) in the airway lumen and lung parenchyma [3]. Marijuana suppresses the ability of AM to phagocytose pathogens with an increased risk of airway infection and lung abscesses [4,5]. There are also suggestions that marijuana smoking increases the risk of lung cancer, although this is as yet not definitely established [6,7].

We describe the case of a 23-year-old Caucasian man with cystic fibrosis (CF) with recurrent pneumothoraces, which were most probably due to “bong lung” and the presence of unusual findings on sputum cytology.

Case Presentation

A 23-year-old Caucasian man with CF was admitted with a one-week history of pleuritic chest pain, increased cough and sputum purulence, accompanied by some minor haemoptysis. Lung function had deteriorated; FEV1 of 2.01L (42% predicted) compared to 2.76L (57% predicted) when well. On examination, he was clubbed and malnourished (body mass index: 18), but not cyanosed. Auscultation of his chest revealed widespread inspiratory crackles over both upper lobes. A diagnosis of an infective exacerbation of his bronchiectasis was made. He was continued on intravenous ceftazidime and tobramycin, regular physiotherapy and nutritional supplementation.

Past medical history consisted of pancreatic insufficiency and chronic airway sepsis related to Pseudomonas aeruginosa infection. Diagnosis had been made at birth and he possessed the ΔF508/1898 + G → CF gene mutation. He was known to have established osteoporosis and significant gastro-oesophageal reflux. Over the preceding two years, he had been admitted to a hospital on 12 occasions with acute exacerbations of his CF lung disease and during this time period, his forced expiratory volume in one second L (FEV1) had deteriorated from 3.17 L (74% predicted) to 2.76L (57% predicted). He also had a past history of recurrent left-sided pneumothoraces.

During the admission, he developed spiking fevers and complained of worsening pleuritic pain. A Computed Tomography (CT) pulmonary angiogram was performed to look for pulmonary emboli. The CT scan showed no emboli, but demonstrated large bilateral upper lobe lung bullae, more prominent on the right side with characteristic bronchiectatic changes elsewhere (Figure ​ (Figure1). 1 ). Sputum microscopy revealed the expected predominance of PMNs, but also droplets of oily brown material embedded in mucus. PMNs were observed containing vacuoles full of this brown-pigmented substance and elsewhere, these droplets could be seen surrounded by palisades of PMNs (Figure ​ (Figure2). 2 ). On closer questioning, the patient admitted to several years of marijuana smoking through a bong. He denied use of tobacco. A provisional diagnosis of “bong lung” complicating severe CF bronchiectasis was made. The patient made a slow recovery over three weeks and received counselling about his marijuana use. He was discharged with an FEV1 of 2.33L (48% predicted).

High resolution CT scan of the patient’s lungs demonstrating apical bullae. Note the prominent bronchial arteries (arrow).

“Bong lung” in cystic fibrosis: a case report Zoe Gao 1 Departments of Respiratory Medicine, Royal Hobart Hospital, Liverpool Street, Hobart, Tasmania, 7000, Australia Richard Wood-Baker