Haematology for MRCP Part 1

A 20-year-old man with known sickle cell disease presents with fever, pleuritic chest pain and breathlessness during a painful crisis. Oxygen saturation is 89%, and a chest radiograph shows new bilateral infiltrates. What is the most likely diagnosis?

1. Other haemolytic anaemia Anaemia with a high reticulocyte count from another cause. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis raises it.
2. Thalassaemia A microcytic haemoglobinopathy without sickling crises. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis redirects it.
3. Acute abdomen from another cause Abdominal pain not due to the disease. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it a consideration.
4. Osteomyelitis Bone pain and fever mimicking a crisis. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis points to a complication.
5. Sickle cell disease correct Correct. Fever, chest pain, hypoxia and new infiltrates in a sickle crisis is the acute chest syndrome.

The point: Sickle cell disease is an autosomal recessive haemoglobinopathy in which a point mutation produces haemoglobin S, which polymerises when deoxygenated and deforms red cells into sickle shapes that haemolyse and occlude small vessels. It presents with a chronic haemolytic anaemia and recurrent painful vaso-occlusive crises, precipitated by cold, dehydration, infection and hypoxia. The acute chest syndrome (fever, chest pain, hypoxia and new infiltrates) is a leading cause of death and needs urgent oxygen, analgesia, antibiotics and often exchange transfusion. Other crises are the aplastic crisis (parvovirus B19 causing a sudden drop in haemoglobin with a low reticulocyte count) and splenic sequestration. Functional hyposplenism from repeated infarction increases the risk from encapsulated organisms, so vaccination and penicillin prophylaxis are given. Long-term care includes hydroxycarbamide, which raises fetal haemoglobin and reduces crises, transfusion in selected cases, and screening for the chronic organ damage of stroke, pulmonary hypertension, retinopathy and renal disease. An acute painful crisis is managed with prompt analgesia (often strong opioids), hydration, oxygen and treatment of any precipitant.

Source: British Society for Haematology — sickle cell disease guidelines British Society for Haematology · tier 2, specialty society or college

A 20-year-old man with known sickle cell disease presents with fever, pleuritic chest pain and breathlessness during a painful crisis. Oxygen saturation is 89%, and a chest radiograph shows new bilateral infiltrates. What is the most appropriate investigation?

1. Screening for chronic organ damage Transcranial Doppler, retinal and renal assessment. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it preventive.
2. Chest imaging and oxygen assessment in a crisis correct Correct. Chest imaging and oxygen assessment identify the acute chest syndrome.
3. Septic screen where infection is suspected Because infection precipitates crises. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it directed.
4. Full blood count and reticulocytes Show the haemolytic anaemia and marrow response. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes them routine.
5. Haemoglobin electrophoresis Confirms haemoglobin S and the diagnosis. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it central.

The point: Sickle cell disease is an autosomal recessive haemoglobinopathy in which a point mutation produces haemoglobin S, which polymerises when deoxygenated and deforms red cells into sickle shapes that haemolyse and occlude small vessels. It presents with a chronic haemolytic anaemia and recurrent painful vaso-occlusive crises, precipitated by cold, dehydration, infection and hypoxia. The acute chest syndrome (fever, chest pain, hypoxia and new infiltrates) is a leading cause of death and needs urgent oxygen, analgesia, antibiotics and often exchange transfusion. Other crises are the aplastic crisis (parvovirus B19 causing a sudden drop in haemoglobin with a low reticulocyte count) and splenic sequestration. Functional hyposplenism from repeated infarction increases the risk from encapsulated organisms, so vaccination and penicillin prophylaxis are given. Long-term care includes hydroxycarbamide, which raises fetal haemoglobin and reduces crises, transfusion in selected cases, and screening for the chronic organ damage of stroke, pulmonary hypertension, retinopathy and renal disease. An acute painful crisis is managed with prompt analgesia (often strong opioids), hydration, oxygen and treatment of any precipitant.

Source: British Society for Haematology — sickle cell disease guidelines British Society for Haematology · tier 2, specialty society or college

A 20-year-old man with known sickle cell disease presents with fever, pleuritic chest pain and breathlessness during a painful crisis. Oxygen saturation is 89%, and a chest radiograph shows new bilateral infiltrates. What is the most appropriate management?

1. Urgent treatment of the acute chest syndrome correct Correct. The acute chest syndrome needs urgent oxygen, antibiotics, analgesia and often exchange transfusion.
2. Treat the precipitating cause Such as infection or dehydration. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it thorough.
3. Vaccination and penicillin prophylaxis For functional hyposplenism. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it preventive.
4. Prompt analgesia, hydration and oxygen for a painful crisis The core of acute management. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it foundational.
5. Transfusion or exchange transfusion in selected cases For severe complications. Fever, chest pain, hypoxia and new infiltrates during a sickle crisis makes it targeted.

The point: Sickle cell disease is an autosomal recessive haemoglobinopathy in which a point mutation produces haemoglobin S, which polymerises when deoxygenated and deforms red cells into sickle shapes that haemolyse and occlude small vessels. It presents with a chronic haemolytic anaemia and recurrent painful vaso-occlusive crises, precipitated by cold, dehydration, infection and hypoxia. The acute chest syndrome (fever, chest pain, hypoxia and new infiltrates) is a leading cause of death and needs urgent oxygen, analgesia, antibiotics and often exchange transfusion. Other crises are the aplastic crisis (parvovirus B19 causing a sudden drop in haemoglobin with a low reticulocyte count) and splenic sequestration. Functional hyposplenism from repeated infarction increases the risk from encapsulated organisms, so vaccination and penicillin prophylaxis are given. Long-term care includes hydroxycarbamide, which raises fetal haemoglobin and reduces crises, transfusion in selected cases, and screening for the chronic organ damage of stroke, pulmonary hypertension, retinopathy and renal disease. An acute painful crisis is managed with prompt analgesia (often strong opioids), hydration, oxygen and treatment of any precipitant.

Source: British Society for Haematology — sickle cell disease guidelines British Society for Haematology · tier 2, specialty society or college