TY - JOUR T1 - A 22-year-old woman with unexplained exertional dyspnoea JF - Thorax JO - Thorax SP - 1057 LP - 1060 DO - 10.1136/thoraxjnl-2016-208330 VL - 71 IS - 11 AU - M Internullo AU - M Bonini AU - P Marinelli AU - E Perli AU - B Cerbelli AU - P Palange Y1 - 2016/11/01 UR - http://thorax.bmj.com/content/71/11/1057.abstract N2 - A 22-year-old woman was referred to our respiratory outpatient clinic to undergo a cardiopulmonary exercise test (CPET), following presentation with a 2-year history of progressive unexplained exertional dyspnoea (ED). Specifically, she described dyspnoea precipitated by walking or running, which gradually improved with rest. She denied chest pain, cough, asthenia or muscular weakness. Until the age of 20, she practised regular non-competitive physical activity.The patient had at term natural childbirth and normal psychophysical development. Menstrual period, started at the age of 14 years, was regular; no pregnancy, nor miscarriage. She was a lifelong non-smoker with no history of illicit substance use or occupational exposure (university student). Her past history included multinodular euthyroid goitre for which she was prescribed regular levothyroxine (75 μg/100 μg on alternate days). She also reported intermittent gastrointestinal discomfort, which had been ascribed to lactose intolerance for which, however, she was not prescribed a lactose-free diet. Her family history revealed an uncle deceased during childhood for ‘cardiac arrhythmia’.Cardiorespiratory and neurological examination was unremarkable. She was normotensive (blood pressure (BP) 100/60 mm Hg, heart rate (HR) 98 bpm in sinus rhythm), not tachypnoeic (respiratory rate 16 breaths/min) and had preserved oxygen saturation (SatO2 98%). Her body mass index was 19.3.Pulmonary function tests showed normal flow indices (FVC 3.52 L—88% of pred; FEV1 3.35 L—96% of pred; Tiffeneau index FEV1/FVC 0.95) and preserved lung volumes and gas transfer (total lung capacity 3.94 L—90% of pred; diffusing capacity of the lungs for carbon monoxide, 96% of pred). A high-resolution chest tomography showed no sign of lung disease.Cardiological (including rest, stress and Holter ECG, as well as cardiac ultrasounds) and neurological (including electromyography) exams showed no abnormalities.Routine blood tests (cell count, glucose and electrolyte levels, iron and ferritin profile, lipid screening, kidney and liver function), erythrocyte sedimentation rate, C reactive protein and muscular enzyme … ER -