Fever and chest pain in sickle cell anaemia: acute chest syndrome
A 19-year-old male university student with sickle cell anaemia (HbSS) presents to an emergency department in Accra with a 2-day history of fever, generalized bone pain, and right-sided chest pain that is worse on inspiration. He has had similar painful crises before, usually managed at home with oral analgesics. On examination: temperature 38.9°C, pulse 118/min, blood pressure 102/64 mmHg, respiratory rate 26/min, SpO2 94% on room air. He is alert but in obvious pain. Chest auscultation reveals reduced air entry at the right base with fine crackles. Abdomen is soft. Investigations: haemoglobin 7.1 g/dL (baseline 7.8), white cell count 18.4 × 10⁹/L, platelets 210 × 10⁹/L, creatinine 88 µmol/L. Chest radiograph shows a new right lower zone infiltrate. Malaria rapid diagnostic test is negative, but he lives in a malaria-endemic area and has not taken prophylaxis. Blood cultures are pending. The hospital has oxygen, intravenous opioids, ceftriaxone, and packed red cells but no exchange transfusion service.
1. Identify the main diagnoses and decide on admission and initial investigations.
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The combination of fever, chest pain, tachypnoea, hypoxaemia, a new infiltrate, and sickle cell disease meets the criteria for acute chest syndrome, which is the leading cause of death in sickle cell disease. He also has a vaso-occlusive painful crisis and likely infection. Admit. Do not treat this as a routine outpatient crisis.
Initial investigations: full blood count with reticulocytes, blood film, blood cultures, malaria film (repeat if RDT negative), urea and electrolytes, liver function, lactate, group and cross-match, and repeat chest radiograph if needed. Check oxygen saturation continuously or regularly. Look for triggers: infection, fat embolism, hypoventilation from pain, and dehydration. Start oxygen if SpO2 falls below 94%, give cautious intravenous fluids, and provide effective analgesia. Because exchange transfusion is not available, identify the nearest centre early and discuss transfer criteria with the family.
2. Outline antibiotic and malaria management and decide whether transfusion is indicated.
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Give broad-spectrum antibiotics promptly because infection is a common trigger and he is febrile with a new infiltrate. A reasonable regimen is ceftriaxone plus a macrolide to cover atypical organisms, adjusted to local resistance patterns. Do not delay antibiotics for blood culture results. Malaria RDT is negative, but in an endemic area with fever, send thick and thin films and treat if positive or if clinical suspicion remains high; do not rely on a single RDT.
Transfusion: in acute chest syndrome, transfuse if haemoglobin is below 7 g/dL or if there is hypoxia, worsening respiratory status, or rapid fall. His Hb is 7.1 g/dL with hypoxaemia, so packed red cells are reasonable; aim for a modest rise and avoid hyperviscosity. If he deteriorates despite simple transfusion, exchange transfusion is preferred, but it is unavailable, so escalate and transfer. Do not transfuse to a normal haemoglobin.
3. Describe your analgesic and monitoring plan and state when you would refer or transfer.
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Give opioid analgesia, for example intravenous morphine titrated to effect, with antiemetics and laxatives; do not withhold opioids because of fears of respiratory depression, but monitor sedation and respiratory rate. Add paracetamol and consider ketamine or other adjuncts if pain is severe. Avoid pethidine because of seizure risk. Encourage incentive spirometry and mobilization; pain limits breathing and worsens atelectasis.
Monitor vital signs, SpO2, fluid balance, pain score, and neurological status. Escalate or transfer if SpO2 falls below 90% despite oxygen, respiratory rate rises above 30/min, he becomes confused or drowsy, chest radiograph worsens, haemoglobin falls, or pain is uncontrolled. Discuss with a haematologist early. Because exchange transfusion is not available locally, do not wait for deterioration before arranging transfer.