A 12-year-old boy is brought to the emergency room due to high fever, chest pains, and dyspnea. Medical history is significant for 2 prior hospitalizations for abdominal pain that resolved with analgesics and hydration. Evaluation today shows a hematocrit of 23% and reticulocyte count of 9%. Several hours after being admitted to the hospital, the patient dies. At autopsy, the spleen is small and firm. This patient's autopsy finding is most likely related to which of the following?

Question

A 12-year-old boy is brought to the emergency room due to high fever, chest pains, and dyspnea.  Medical history is significant for 2 prior hospitalizations for abdominal pain that resolved with analgesics and hydration.  Evaluation today shows a hematocrit of 23% and reticulocyte count of 9%.  Several hours after being admitted to the hospital, the patient dies.  At autopsy, the spleen is small and firm.  This patient's autopsy finding is most likely related to which of the following?

Quizplus · Accepted Answer

11ec160b_3995_9be3_9249_75b18527872c_MD0001_00 This patient's hematologic findings (eg, anemia, reticulocytosis) and medical history (eg, recurrent episodes of abdominal pain that resolved with analgesics and hydration) are suggestive of sickle cell disease (SCD). SCD is a hemoglobinopathy characterized by sickle hemoglobin (HbS), an abnormal hemoglobin that can polymerize in deoxygenated conditions. HbS polymerization leads to sickle-shaped erythrocytes that can occlude small vessels. This patient's most recent presentation (eg, fever, chest pain, dyspnea) was most likely due to small-vessel occlusion localized to the pulmonary vasculature (ie, acute chest syndrome). Vascular occlusion can also cause splenic infarctions. Repeated infarctions produce a shrunken, fibrotic spleen. By adulthood, most patients with SCD have undergone autosplenectomy and have a small, scarred splenic remnant. As a result, these patients have functional asplenia and are susceptible to infection with encapsulated organisms (eg, Streptococcus pneumoniae). (Choice A) Extramedullary hematopoiesis (EMH) can develop in patients with hemolytic anemias (eg, beta-thalassemia, SCD) or myeloproliferative neoplasms (eg, primary myelofibrosis) and typically occurs in the liver and spleen. Splenic EMH would result in splenomegaly, not splenic atrophy. (Choice B) Splenic follicular hyperplasia can be seen with systemic infections and can result in an enlarged, not small and firm, spleen. (Choice C) Intrasplenic lipid accumulation may occur in lysosomal storage disorders such as Gaucher disease. Although such patients can have bone pain and anemia, they typically have splenomegaly. (Choice D) Pressure atrophy of the splenic parenchyma can be seen when a lesion (eg, a cyst) compresses the spleen, which would likely have been detected during autopsy. Educational objective: In patients with sickle cell disease, repetitive splenic infarctions caused by microvessel occlusion result in a small, firm splenic remnant (ie, autosplenectomy).

A 12-Year-Old Boy Is Brought to the Emergency Room Due