Thalassemias comprise a variable group of anemias caused by an abnormality in the production globin subunits of hemoglobin (Hb). This autosomal recessive inherited defect may result in severe complications, including iron overload, ineffective erythropoiesis, and chronic hemolytic anemia. The prognosis of patients with thalassemia has greatly improved in recent years due to advances in diagnosis, supportive care, and treatment. As a result, many patients live with long-term complications of the disease, which may necessitate urgent medical care in the emergency department (ED).1,2
In a review article published in Annals of Hematology, Antoine N. Saliba, MD, of the department of medicine at the Mayo Clinic in Rochester, Minnesota, and colleagues summarized current literature surrounding the frequent complications that bring patients with thalassemia into the ED. In addition, they reviewed the elements of emergency care most relevant to providing optimal care for patients with thalassemia.1
Initial ED Presentation
At initial presentation to the ED, conducting a detailed medical history is important for patients with thalassemia. Clinicians should focus questions on transfusion history, iron chelation regimen, iron load, and splenectomy status. Past history of fractures, infections (HIV, hepatitis B or C), vaccinations (Haemophilus influenzae type b, influenza, meningococcal, and pneumococcal vaccines), and surgeries (splenectomy or cholecystectomy) are also pertinent to the clinical workup. In addition, asking about travel history to malaria-endemic areas, and conducting a thorough drug history is also important.
Similar to patients without thalassemia who present with hemodynamic instability, resuscitation and stabilization is required before further evaluation can occur.
Patients with transfusion-dependent thalassemia (TDT) may require blood transfusions to maintain a target Hb range of 9.5 to 10 g/dL, whereas patients with non-TDT have a wide range of stable Hb levels between 6 and 9 g/dL and may only require intermittent transfusion support.
A complete blood count should be ordered before each transfusion in patients with TDT in order to maintain a steady state of Hb. These patients are dependent on blood transfusions with a tight schedule (every 3-4 weeks) and a large transfusion volume (up to 20 mL/kg). Patients with TDT should receive blood that is at most 10 days old, negative for Kell antigen, and marched for extended rhesus phenotype to mitigate the risk for transfusion-related complications, such as hemolytic transfusion reactions, alloimmunization, acute transfusion reactions, transfusion-transmitted infections, and febrile and allergic reactions.
To manage patients with thalassemia who present to the ED with symptomatic anemia, assess for the following: TDT status at baseline and if the patient presents with fever, abdominal pain, jaundice, indirect hyperbillirubinemia, low haptoglobin, or tests positive for red blood cell allo- or auto-antibodies.
If the patient presents with any of these symptoms, clinicians should consider that alloimmunization could cause a delayed transfusion hemolytic reaction with hyperhemolysis syndrome. In this situation, red blood cell transfusion should be avoided and a thalassemia specialist should be consulted.
If the patient does not present with any of these symptoms, clinicians should look for signs of hemorrhage, such as epistaxis or gastrointestinal bleeding. If hemorrhage is observed, clinicians should control the bleeding site and transfuse red blood cell units accordingly.
In the absence of hemorrhage, clinicians should assess whether the patient’s transfusion schedule was delayed. If the schedule was delayed, red blood cells can be transfused to accommodate the schedule. If there is no delay, clinicians should look for a low reticulocyte count with or without a decrease in white blood cell and platelet counts to determine whether the patient has a folate or vitamin B12 deficiency, or if the patient has an infection.