Coexistent COVID-19 pneumonia and pulmonary embolism: challenges in identifying dual pathology

In early March 2020, a 53-year-old man was admitted to King’s College Hospital (KCH). He presented with a 2-week history of a dry cough, followed by fevers. He had a long flight 9 weeks prior to admission. His presentation to the emergency department was prompted by feeling increasingly breathless; his cough was occasionally productive of yellow sputum with streaks of haemoptysis. He had no medical history. His temperature was 38°C with peripheral oxygen saturation level of 92% on room air, respiratory rate was 28 breaths per minute but he was haemodynamically stable with blood pressure 128/75 mm Hg and heart rate 98 beats per minute. A chest X-ray on arrival showed bilateral infiltrates with denser consolidation in the right lower and upper zone. An arterial blood gas showed type 1 respiratory failure with pH 7.52, PaCO2 3.87 kPA, PaO2 8.45 kPa and lymphopenia 0.86×109/L. ECG demonstrated sinus rhythm. The patient was suspected to have viral pneumonia—likely COVID-19. He was given oxygen to target saturations 94%–98%, covered for bacterial infection as per local community-acquired pneumonia protocol and given venous thromboembolism (VTE) prophylaxis in the form of enoxaparin 40 mg once daily. Viral RT-PCR (reverse transcription polymerase chain reaction) for COVID-19 from naso-oropharyngeal and oropharyngeal swabs on both day 1 and day 2 of admission were negative. Urinary pneumococcal and legionella antigens were also negative. His D dimer was 2560 ng/mL (normal <500 ng/mL) and serial troponin Ts were 3 and 7 ng/L …