Muppet wants to test your diagnostics skills with the following case of a 39-year-old smoker with dyspnea. Check the images below, leave your diagnosis in the comments, and come back on Friday for the answer.
1. Bronchogenic carcinoma
2. Endobronchial TB
3. Benign endobronchial tumour
4. None of the above
Findings: the chest radiograph shows a typical RUL collapse, confirmed with unenhanced coronal CT, which shows occlusion of the RUL bronchus (Fig. 1B, arrow).
Fig. 1
The clue to the diagnosis lies in identifying high-opacity branching structures within the collapsed lobe (Fig. 2 A-C, arrows).
Fig. 2
Since the RUL is obstructed, they most likely represent mucous impaction. As the main cause of dense mucous impaction is allergic bronchopulmonary aspergilosis, this is the most likely diagnosis. This suspicion was confirmed at bronchoscopy. After removal of the plugs, the chest showed marked improvement (Fig. 3).
Fig. 3
Final diagnosis: ABPA, causing RUL collapse.
Congratulations to Gaborini and Laurens who made back-to-back diagnoses.
Teaching point: it is important to know useful signs, because you never know when they are going to help. I have made brilliant diagnoses by recognising the dense mucous plugs … except in this particular case, in which I overlooked them! Nobody is perfect!
