You see a 25 year old man who has been discharged from hospital last week following a non-traumatic Pneumothorax. He has no past medical history apart from Eczema and is usually fit and well. The discharge letter has not come through yet to the GP surgery but he mentions the hospital suspected he had a genetic condition putting him at higher risk. You note he is quite tall and slim and agree that he may need to see a geneticist.
Which one of the below findings would you most likely expect to see on examination based on his likely condition?