A young woman with fever and loss of consciousness

A 22 year old woman was admitted to hospital with confusion, pyrexia, and two episodes of loss of consciousness while at work that day. She described having felt tired in the preceding week. She had no medical history of note and did not smoke or drink alcohol. She did not take any regular medications and did not use recreational drugs. The patient was born in the UK. Her parents were from Nigeria. She had no recent foreign travel or contact with anyone who was unwell. Her heart rate was 115 beats/min, blood pressure 100/80 mm Hg, temperature 38.5°C, respiratory rate 20 breaths/min, and oxygen saturations 100% on room air. Blood results are shown in table 1 and blood film in fig 1. View this table: Table 1 Blood test results Fig. 1 Blood film ×40 magnification 1. What is the most likely diagnosis? 2. What other initial tests are important? 3. How is this condition treated? ### 1. What is the most likely diagnosis? The following factors make thrombotic thrombocytopenic purpura (TTP) the most likely diagnosis: Fig. 2 Blood film ×40 magnification showing schistocytes and thrombocytopenia TTP requires immediate haematologist assessment. TTP is a thrombotic microangiopathy. Haemolytic uraemic syndrome, another thrombotic microangiopathy, is a differential. Thrombotic microangiopathy (TMA) is indicated by thrombocytopenia in the full blood count and microangiopathic haemolytic anaemia on the blood film.1 ADAMTS13 enzyme activity …