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Sickle cell disease (SCD) is a chronic hemolytic anemia that is most common among African Americans, but may occur in children of any ethnic background. Patients with a single abnormal gene for HbS have sickle cell trait and remain essentially asymptomatic.
Acute vasoocclusive crisis (VOC) events (painful crisis events) are the most common complication of SCD and are the most frequent cause of emergency department visits.
A complete blood count and reticulocyte count should be obtained every time a patient with SCD presents to the emergency department (ED).
Patients with SCD presenting with a new infiltrate on chest radiograph, and chest pain, fever, and/or respiratory symptoms have acute chest syndrome (AChS). Therapy for AChS consists of antibiotics, pain control, respiratory support, and possibly transfusion. All children with AChS should be admitted to the hospital.
A blood culture should be obtained and parenteral antibiotic given to every patient with SCD and fever due to the risk of sepsis from encapsulated bacteria, especially Streptococcus pneumoniae.
Splenic sequestration crisis occurs when red blood cells (RBCs) become entrapped in the spleen, resulting in a rapidly enlarging spleen and a sudden drop in hemoglobin. The mainstay of therapy is blood transfusion.
Stroke occurs in 11% of patients with SCD under 20 years of age. Patients with signs and symptoms concerning for stroke should have neuroimaging performed (preferably magnetic resonance imaging [MRI] and magnetic resonance angiography [MRA]) and consultation with a hematologist as soon as possible.
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Patients with sickle cell disease (SCD) experience a number of complications that are likely to bring them to the emergency department (ED). Hemoglobin S (HbS) is a variant resulting from a single nucleotide mutation in the sixth codon of the β-globin gene leading to the substitution of hydrophobic valine for the normal hydrophilic glutamic acid. SCD occurs when an individual is homozygous for HbS or is a compound heterozygote for HbS and another interacting β-globin variant. The most common combination of hemoglobins leading to SCD are HbSS (sickle cell anemia), HbSC (hemoglobin SC) disease, and HbS-β thalassemia (either β0 or β+). Although there is wide variability in individual severity of illness, patients with HbSS or HbSβ0 (no hemoglobin A production) have the greatest severity of disease.1,2 The other double heterozygous states, such as HbSC and HbSβ+ thalassemia, are typically less seriously affected.1 Patients with HbS/HPFH (hereditary persistence of HbF) and HbS/HbE show mild to no symptoms.1 Approximately 1 in 12 African Americans carry the allele, and 1 in 500 African Americans born has the disease. HbS also occurs in people of Mediterranean, South Asian, and Middle Eastern descent.1
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Patients with a single abnormal gene for HbS have sickle cell trait. The concentration of HbS is typically 40%, and the large percentage of normal hemoglobin allows the patients to remain asymptomatic except under the most severe hypoxic stress. Sickle trait should be considered ...