Haemorrhage, hyponatraemia and more than just a hack

A 43-year-old previously healthy solicitor presented with a 9-day history of cough productive of yellow sputum with a prodrome of sore throat and myalgia. The cough was paroxysmal in nature and severe enough to cause extensive bilateral subconjunctival haemorrhages and cough syncopes multiple times a day, with one bout of associated haematemesis on the day of admission. He was isolated, treated for a presumed atypical chest infection with tazocin and clarithromycin, and monitored carefully until the hyponatraemia on presentation was resolved. Atypical screen and blood cultures were sent off, though unexciting at first, eventually confirmed the unlikely; Bordetella pertussis, much to the surprise of many who had Legionella as the top differential.