Diagnosis of Acute Pain Episodes in Sickle Cell Disease
The diagnosis of an acute pain episode in sickle cell disease is based entirely on the patient's self-report of pain, without requiring any specific laboratory abnormalities or diagnostic tests. 1
Core Diagnostic Principle
The diagnosis is purely clinical and relies on patient history alone. 1 Patients with sickle cell disease and their caregivers typically know their disease best, and their report of typical pain symptoms should be trusted and acted upon promptly without delay for confirmatory testing. 1
What Is NOT Required for Diagnosis
No laboratory abnormalities are needed - The presence or absence of specific lab findings does not confirm or exclude an acute pain episode. 1
Sickle cells on peripheral smear - These are chronically present in patients with sickle cell disease and do not distinguish acute pain episodes from baseline. 1
Elevated inflammatory markers - While laboratory markers such as lower hemoglobin, elevated lactate dehydrogenase, bilirubin, aspartate aminotransferase, reticulocyte count, white blood cells, and platelet counts may be present (particularly in priapism), these are not used to diagnose the acute pain episode itself. 2, 1
Clinical Features to Recognize
Pain distribution varies by age:
- Infancy: Typically affects the fingers (dactylitis). 1
- Older children and adults: Commonly involves long bones, sternum, ribs, or back. 1
Critical Exclusions Required
While the diagnosis itself is clinical, you must actively exclude life-threatening complications:
Acute Chest Syndrome (ACS)
- Mandatory exclusion in chest pain - The American College of Cardiology gives a Class I recommendation to exclude acute chest syndrome in patients presenting with chest pain. 1, 3
- ACS is characterized by new infiltrate on chest radiograph with respiratory symptoms. 1
- This is a leading cause of death with up to 13% all-cause mortality. 3
Acute Coronary Syndrome
- Must be excluded in adolescent patients with chest pain, as AMI occurs at relatively early age without traditional risk factors in sickle cell disease. 3
- Obtain 12-lead electrocardiogram and troponin level. 3
Splenic Sequestration Crisis
- Characterized by a drop in hemoglobin >2 g/dL, which distinguishes it from typical vaso-occlusive pain episodes. 1
Transient Aplastic Crisis
- Characterized by a decreased reticulocyte count, not typical of acute pain episodes. 1
Management Implications of Clinical Diagnosis
Once the patient reports pain consistent with their typical crisis pattern:
Rapid triage is essential - The clinical diagnosis should trigger immediate action. 1
Aggressive parenteral analgesia with opioids should be administered promptly - First analgesic dose should be given within 30 minutes of triage. 1, 3
Use scheduled around-the-clock dosing or patient-controlled analgesia (PCA) for severe pain rather than as-needed dosing. 1, 3
Common Pitfalls to Avoid
Do not delay treatment waiting for laboratory confirmation - The diagnosis is clinical, and waiting for labs before initiating analgesia worsens outcomes. 1
Do not dismiss patient reports of pain - In recurrent ischemic priapism (such as in sickle cell disease), the diagnosis may be abundantly clear by history and examination alone, and additional testing may be omitted at the clinician's discretion. 2
Do not assume normal labs exclude a pain crisis - Laboratory values do not guide the diagnosis of acute pain episodes. 1