Abnormal chest radiograph in pregnancy

A 28 year old woman of Pakistani origin, who was 18 weeks pregnant, presented with a four week history of dry cough, breathlessness, and intermittent wheeze. Antibiotics and inhaled bronchodilators had been prescribed with no improvement in symptoms. She was a never smoker and drank no alcohol. Six years previously she had been treated for smear and culture positive, fully sensitive, pulmonary tuberculosis. After this she had developed a right-sided pneumothorax, which resolved after insertion of an intercostal chest drain. She had no history of pre-existing airways disease. On examination she was able to talk in full sentences, she had a normal temperature but was tachypnoeic, with a respiratory rate of 24 breaths/min and oxygen saturation of 91% on room air. Respiratory examination showed scattered wheeze throughout. Her pulse was 74 beats/min and blood pressure was 103/71 mm Hg. The rest of the cardiovascular examination was normal. Abdominal examination was consistent with 18 weeks of pregnancy. Arterial blood gases on room air showed mild hypoxia, with partial pressure of oxygen at 7.98 kPa. Peak expiratory flow rate on admission was 150 L/min. Spirometry (done at a later date when she was clinically stable) showed a forced expiratory volume in one second of 0.89 L (34% of predicted). A chest radiograph was performed (fig 1⇓), followed by bronchoscopy, which showed a necrotic tumour in the right upper lobe.