Which of the following anaemias is a risk factor for the development of gastric carcinoma
**Core Concept**
Pernicious anaemia is a type of megaloblastic anaemia caused by a lack of intrinsic factor, leading to vitamin B12 deficiency. It is associated with autoimmune gastritis, which can increase the risk of gastric carcinoma.
**Why the Correct Answer is Right**
The underlying mechanism involves chronic inflammation and mucosal atrophy in the stomach, resulting from autoimmune gastritis. This leads to a decrease in the production of intrinsic factor, a protein necessary for vitamin B12 absorption. Vitamin B12 deficiency can cause megaloblastic anaemia, characterized by the production of abnormally large red blood cells. The chronic inflammation and mucosal damage associated with pernicious anaemia increase the risk of gastric carcinoma, particularly adenocarcinoma.
**Why Each Wrong Option is Incorrect**
**Option A:** Iron deficiency anaemia is a common condition, but it is not directly associated with an increased risk of gastric carcinoma. Iron deficiency anaemia can be caused by chronic blood loss, but this is not a risk factor for gastric cancer.
**Option B:** Thalassemia is a genetic disorder affecting haemoglobin production, leading to various forms of anaemia. While thalassemia can increase the risk of certain complications, such as osteoporosis and heart disease, it is not a risk factor for gastric carcinoma.
**Option C:** Sideroblastic anaemia is a rare condition characterized by the accumulation of iron in mitochondria, leading to ineffective haemoglobin production. This type of anaemia is not directly associated with an increased risk of gastric carcinoma.
**Clinical Pearl / High-Yield Fact**
Autoimmune gastritis, which is associated with pernicious anaemia, can also lead to a decrease in the production of intrinsic factor, resulting in vitamin B12 deficiency. This can cause neurological symptoms, including numbness, weakness, and cognitive impairment.
**Correct Answer:** C. Pernicious anaemia.