A 6 month old child with sickle cell anemia has a chronically enlarged spleen. By 5 years of age, the child’s spleen is no longer palpable. The decrease in size is most likely related to which of the following?
**Core Concept**
Sickle cell anemia is a genetic disorder characterized by the production of abnormal hemoglobin (HbS), leading to vaso-occlusive crises, chronic anemia, and increased risk of infections. The spleen is often affected, leading to autosplenectomy (shrinkage or loss of splenic function), particularly in children with sickle cell disease.
**Why the Correct Answer is Right**
In sickle cell anemia, repeated vaso-occlusive crises cause microvascular damage and fibrosis in the spleen. This leads to decreased splenic function, resulting in the loss of splenic sequestration and filtering capabilities. Over time, the spleen becomes non-functional, and its size decreases, a phenomenon known as autosplenectomy. This process is more likely to occur in children with sickle cell disease due to the increased frequency and severity of vaso-occlusive crises.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not directly relate to the pathophysiology of sickle cell anemia and autosplenectomy.
**Option B:** This option is incorrect as it is not directly related to the decrease in size of the spleen in sickle cell anemia.
**Option C:** This option is incorrect as it is a general term and does not specifically relate to the pathophysiology of autosplenectomy in sickle cell anemia.
**Clinical Pearl / High-Yield Fact**
In patients with sickle cell anemia, the loss of splenic function can lead to increased susceptibility to infections, particularly encapsulated organisms such as Streptococcus pneumoniae and Haemophilus influenzae.
**Correct Answer: A. Autosplenectomy due to repeated vaso-occlusive crises.**