All of following cause intravascular hemolysis, except-
**Core Concept**
Intravascular hemolysis refers to the breakdown of red blood cells within the blood vessels, leading to the release of hemoglobin and other cellular components into the circulation. This can be caused by various factors, including mechanical damage, enzymatic degradation, or immune-mediated mechanisms.
**Why the Correct Answer is Right**
Intravascular hemolysis can be caused by conditions such as:
* Mechanical damage: Shear stress in microcirculation (e.g., severe burns, sepsis), mechanical heart valves, or prosthetic heart valves.
* Enzymatic degradation: Paroxysmal nocturnal hemoglobinuria (PNH), glucose-6-phosphate dehydrogenase (G6PD) deficiency, or other enzymatic deficiencies.
* Immune-mediated mechanisms: Autoimmune hemolytic anemia (AIHA), warm autoimmune hemolytic anemia (WAHA), or cold agglutinin disease.
**Why Each Wrong Option is Incorrect**
* **Option A:**
* **Option B:**
* **Option C:**
* **Option D:**
**Clinical Pearl / High-Yield Fact**
Intravascular hemolysis can lead to the release of free hemoglobin, which can bind to nitric oxide and reduce its vasodilatory effects, potentially contributing to thrombotic complications.
**Correct Answer:** A.