Pediatrics · Year 3 · from Pediatrics

Case 1: Sickle Cell Disease with Acute Chest Syndrome

Patient Demographics

  • Age: 8-year-old male
  • Sex: Male

Chief Complaint

"He has chest pain, fever, and trouble breathing."

History of Present Illness

An 8-year-old male with known sickle cell disease (HbSS) presents with 2 days of progressive chest pain, fever, and shortness of breath. He was admitted 4 days ago for a vaso-occlusive pain crisis affecting his back and legs, which was being managed with IV fluids and morphine. Yesterday, he developed a new cough and fever to 38.9°C. Today, he has worsening chest pain, especially with deep breathing, and his oxygen saturation has dropped. He has a history of 3 previous vaso-occlusive crises and one prior episode of acute chest syndrome at age 5. He takes hydroxyurea 20 mg/kg daily and folic acid. He has not yet started chronic transfusion therapy.

Physical Examination

  • General: Ill-appearing, tachypneic child in moderate respiratory distress
  • Vital signs: Temp 39.2°C, HR 130 bpm, RR 32/min, SpO2 88% on room air, BP 100/65 mmHg
  • HEENT: Pale conjunctivae, icteric sclerae
  • Cardiovascular: Tachycardic, II/VI systolic flow murmur
  • Respiratory: Decreased breath sounds at right base, dullness to percussion, crackles on right
  • Abdomen: Soft, spleen not palpable (auto-infarcted)
  • Extremities: No acute joint swelling, no dactylitis

Workup

  • CBC: WBC 18,500/μL, Hgb 6.8 g/dL (baseline 8.5), Platelets 380,000/μL, Reticulocytes 12%
  • CMP: Normal
  • LDH: 850 U/L (elevated)
  • Chest X-ray: New right lower lobe infiltrate with small pleural effusion
  • ABG: pH 7.35, pCO2 32 mmHg, pO2 58 mmHg on room air

Diagnosis

Acute chest syndrome complicating vaso-occlusive crisis

Clinical Reasoning

This patient meets the definition of acute chest syndrome: new pulmonary infiltrate on chest X-ray with at least one of fever, respiratory symptoms, or hypoxia, in a patient with sickle cell disease. ACS is the leading cause of death in sickle cell disease. The pathophysiology is multifactorial, including vaso-occlusion in the pulmonary vasculature, infection, and fat embolism from bone marrow infarction. The worsening anemia (drop from baseline of 8.5 to 6.8) reflects both hemolysis and acute illness. This case illustrates that ACS often develops during hospitalization for vaso-occlusive crisis.

Management

  1. Respiratory support: Supplemental oxygen to maintain SpO2 >95%; incentive spirometry every 2 hours while awake
  2. Transfusion: Simple transfusion to Hgb 10 g/dL or exchange transfusion to reduce HbS to <30% if severe (exchange preferred given severity)
  3. Antibiotics: Ceftriaxone plus azithromycin (cover typical and atypical organisms)
  4. Bronchodilators: Albuterol if wheezing present
  5. Pain management: Continue analgesia but monitor for respiratory depression
  6. VTE prophylaxis: Consider given hypercoagulable state
  7. Long-term management: Discuss chronic transfusion program or optimizing hydroxyurea dose; consider referral for hematopoietic stem cell transplant evaluation

Clinical Image

Image Description: Peripheral blood smear showing sickle-shaped red blood cells characteristic of sickle cell disease, demonstrating the abnormal hemoglobin polymerization that causes vaso-occlusion.

Source: Wikimedia Commons URL: https://commons.wikimedia.org/wiki/File:Sickle_cells.jpg License: CC BY-SA 3.0

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