**Question:** Glucose-6-phosphate dehydrogenase (G6PD) deficiency causes

A. Increased susceptibility to infections
B. Hemolytic anemia
C. Impaired wound healing
D. Altered glucose regulation

**Correct Answer:** B. Hemolytic anemia

**Core Concept:**
Glucose-6-phosphate dehydrogenase (G6PD) is an enzyme that plays a crucial role in the pentose phosphate pathway, which is essential for red blood cell (RBC) survival. RBCs lack nucleus and mitochondria, relying entirely on G6PD to produce reduced nicotinamide adenine dinucleotide phosphate (NADPH) and maintain the glutathione/redox balance within the cell. Glucose-6-phosphate dehydrogenase deficiency occurs when an individual has a reduced or absent G6PD enzyme activity. This deficiency leads to an increased vulnerability to oxidative stress, particularly when RBCs are exposed to certain drugs or foods (e.g., fava beans).

**Why the Correct Answer is Right:**
G6PD deficiency results in impaired production of NADPH and increased oxidative stress, which causes damage to RBCs and hemolysis (breakdown of RBCs). This leads to a condition known as hemolytic anemia, characterized by the destruction of RBCs, resulting in low hemoglobin levels, jaundice (due to increased bilirubin production), and other clinical manifestations.

**Why Each Wrong Option is Incorrect:**

A. Increased susceptibility to infections: G6PD deficiency does not directly affect the immune system, so this option is incorrect.

C. Impaired wound healing: G6PD deficiency does not influence the healing process; it primarily affects RBCs and hemolysis.

D. Altered glucose regulation: G6PD deficiency does not impact glucose regulation; it specifically affects RBCs and their susceptibility to oxidative stress.

**Clinical Pearl:**

Glucose-6-phosphate dehydrogenase deficiency is a common X-linked genetic disorder affecting males more frequently than females. It is essential for medical professionals to be aware of this condition when prescribing medications like sulfasalazine, primaquine, or phenazopyridine, as these drugs can trigger acute hemolysis in patients with G6PD deficiency. This can lead to severe anemia, jaundice, and even renal failure in severe cases.