Granulomatosis with polyangiitis, or Wegener granulomatosis, is a rare systemic vasculitis that can affect any organ. The lungs and kidneys are almost always affected. We present a 36-year-old Saudi man who presented with chronic cough, haemoptysis and intermittent dyspnoea. He had been repeatedly misdiagnosed as having respiratory infection and had received multiple courses of antibiotics with little improvement. He responded dramatically to treatment with corticosteroid pulse therapy, plasmapheresis, and rituximab. There are very few reports of granulomatosis with polyangiitis from Saudi Arabia, and the prevalence of the condition is not known. A high index of suspicion can help avoid delayed diagnosis.