Duncan is a 42-year-old business manager who presents with eight days of chest discomfort.

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<p>Duncan is a 42-year-old business manager who presents with eight days of chest discomfort.</p><p>He describes a constant ache, aggravated by exertion but incompletely relieved with rest. The pain is poorly localised in the central chest and epigastrium.</p><p>He has experienced two episodes of night sweats. There is no associated cough, shortness of breath or weight loss.</p><p>He had a bad bout of gastroenteritis two weeks ago after a family holiday in South-East Asia. His gastrointestinal symptoms settled, but he has felt “subpar” since.</p><p>Duncan is usually very well, with no known cardiovascular risk factors. He has no history of recreational drug use and is in a long-term monogamous relationship with no other sexual contacts.</p><p>On examination, vital signs — including temperature and oxygen saturation — are unremarkable.</p><p>Cardiorespiratory and gastrointestinal examination is normal, as is his ECG.</p><p>He is referred to ED, where troponin is negative but CRP and ESR are elevated, with a marked lymphocytic leucocytosis. His chest X-ray is pictured.</p>

Dr Kate Kelso is a GP and medical editor at Australian Doctor.