MRCP2-4541
A 65-year-old woman presents to the Emergency department with a one-week history of increasing breathlessness and coughing up small amounts of blood. She also reports frequent nosebleeds and headaches over the past two months, as well as feeling generally lethargic and losing weight. On examination, there are no signs of cyanosis, finger clubbing, pallor, or skin rash. The pulse is 100 beats/min and BP is 135/95 mmHg. Respiratory rate is 28 breaths/min, chest expansion is moderate, and inspiratory crackles are heard at the left lung base.
The following investigations were conducted: Hb 100 g/L (115-165), WCC 19.9 ×109/L (4-11), Platelets 540 ×109/L (150-400), Plasma sodium 139 mmol/L (137-144), Plasma potassium 5.3 mmol/L (3.5-4.9), Plasma urea 30.6 mmol/L (2.5-7.5), Plasma creatinine 760 µmol/L (60-110), Plasma glucose 5.8 mmol/L (3.0-6.0), Plasma bicarbonate 8 mmol/L (20-28), Plasma calcium 2.23 mmol/L (2.2-2.6), Plasma phosphate 1.7 mmol/L (0.8-1.4), Plasma albumin 33 g/L (37-49), Bilirubin 8 µmol/L (1-22), Plasma alkaline phosphatase 380 U/L (45-105), Plasma aspartate transaminase 65 U/L (5-35). Arterial blood gases on air reveal: pH 7.2 (7.36-7.44), pCO2 4.0 kPa (4.7-6.0), pO2 9.5 kPa (11.3-12.6). ECG shows sinus tachycardia and chest x-ray reveals a shadow in the left lower lobe. Urinalysis shows blood +++ and protein ++.
Which of the following would you expect to be positive in this patient?