A rare presentation of Legionnaires' disease.

We present an interesting case of Legionnaires' disease masquerading as acute pyelonephritis, with complete absence of respiratory symptoms on admission. A 45-year-old man was diagnosed with Legionnaires' disease 2 days after presenting to hospital with dysuria and right loin pain. He became critically unwell during the hospital admission, with headache, uncontrolled fever, breathlessness, decreasing oxygen saturations and increasing oxygen requirements. A CT pulmonary angiography demonstrated right upper lobar consolidation and Legionella urinary antigen was positive. He was treated with ciprofloxacin and rifampicin and made a full recovery.