Aplastic anemia in sickle cell anemia is due to infection of –
**Core Concept**
Aplastic anemia in sickle cell anemia is a rare but severe complication that occurs due to bone marrow failure, leading to a decrease in blood cell production. This condition is often precipitated by an underlying infection.
**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of parvovirus B19 infection, which is a common cause of aplastic crisis in patients with sickle cell anemia. Parvovirus B19 infects red blood cell precursors in the bone marrow, leading to a temporary cessation of red blood cell production. This results in an aplastic crisis, characterized by severe anemia, which can be life-threatening in patients with sickle cell anemia. The virus exploits the fact that the host lacks antibodies against parvovirus B19, making it a significant pathogen in individuals with compromised immune systems.
**Why Each Wrong Option is Incorrect**
**Option A:** This option might be tempting as a viral cause, but it is not the correct answer. Other viruses like CMV, EBV, and HIV can also lead to bone marrow suppression, but they are not the primary cause of aplastic anemia in sickle cell anemia.
**Option B:** This option might be a distractor as it is a bacterial infection. However, bacterial infections like salmonella and E. coli can trigger a crisis in sickle cell anemia patients, but they are not the direct cause of aplastic anemia.
**Option C:** This option is incorrect as it is a fungal infection. Fungal infections can be opportunistic in immunocompromised patients, but they are not the primary cause of aplastic anemia in sickle cell anemia.
**Clinical Pearl / High-Yield Fact**
Parvovirus B19 infection can be prevented by avoiding close contact with infected individuals, especially during outbreaks. It is essential to recognize the signs and symptoms of parvovirus B19 infection, such as mild fever, rash, and joint pain, and to investigate for this infection in patients with sickle cell anemia who develop an aplastic crisis.
**Correct Answer:** B. Parvovirus B19 infection.