Which nutrient deficiency is the main reason for microcytic anemia?

RUHS, Jaipur, PB B.Sc Nursing Entrance-2020

Pathology & Genetics

Easy

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2020

Explanation

Iron is a fundamental component of the heme molecule within hemoglobin, which is essential for oxygen transport by red blood cells (RBCs).
A deficiency in iron directly impairs the synthesis of hemoglobin.
The bone marrow responds to inadequate hemoglobin by producing RBCs that are smaller than normal (microcytic) and contain less hemoglobin, making them paler (hypochromic).
Iron deficiency is the most prevalent nutritional disorder worldwide and the leading cause of microcytic anemia.

Option A: Folic acid deficiency impairs DNA synthesis, which affects rapidly dividing cells like hematopoietic precursors in the bone marrow. This results in megaloblastic anemia, a type of macrocytic anemia where red blood cells are abnormally large, not small.
Option B: While amino acids are the building blocks of proteins, including the globin chains of hemoglobin, a deficiency is not the primary or most common cause of microcytic anemia. Severe protein malnutrition typically leads to normocytic anemia.
Option D: Vitamin C's primary role in this context is to enhance the absorption of non-heme iron from the gastrointestinal tract by converting ferric iron (Fe3+) to the more absorbable ferrous form (Fe2+). Its deficiency does not directly cause microcytic anemia; the primary deficiency disease is scurvy.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Pathophysiology and nutritional causes of microcytic anemia as background academic context rather than a clinical decision trigger.
Nurses play a key role in identifying patients at risk for iron deficiency anemia, such as menstruating women, pregnant women, toddlers, and individuals with chronic blood loss or poor dietary intake.
Patient education is a critical nursing intervention, focusing on dietary sources of iron (e.g., red meat, leafy greens, fortified cereals) and the correct way to take iron supplements (e.g., with vitamin C to enhance absorption, on an empty stomach if tolerated).
What if? If a patient with diagnosed microcytic anemia does not respond to oral iron therapy, the nurse should anticipate further investigations for underlying causes like chronic occult bleeding (e.g., from the GI tract), malabsorption disorders (e.g., celiac disease), or a misdiagnosis (e.g., thalassemia).

How to Approach the Question

First, identify the key terms in the question: 'microcytic anemia' and 'main reason' for a 'nutrient deficiency'.
Recall the classification of anemias based on red blood cell (RBC) size, indicated by the Mean Corpuscular Volume (MCV). 'Microcytic' means small RBCs.
Systematically review the options and associate each nutrient with the type of anemia it causes.
Remember that iron is the essential building block for hemoglobin. Its deficiency logically leads to smaller, hemoglobin-poor cells (microcytic, hypochromic anemia).
Remember that folic acid and vitamin B12 are crucial for DNA synthesis. Their deficiency leads to large, immature cells (macrocytic, megaloblastic anemia).
Evaluate the role of Vitamin C as an enhancer of iron absorption, not a direct cause.

Concept Tested & Keywords

QejzzvUYbaivcETt39oKFJ

E6 Pathology- ROBBINS & COTRAN PATHOLOGIC BASIS OF DISEASE 10TH Ed p. 657-659

E6 Ghai Essential Pediatrics(pp 26-904 of 913) p. 111-113

E6 Biochemistry U Satyanarayana— Part 2 (pp 421-820 of 840) p. 45-47