Shigella associated hemolytic uramic syndrome is associated with all of the following except?
**Core Concept**
Shigella-associated hemolytic uremic syndrome (HUS) is a type of kidney injury caused by Shigella toxin-producing bacteria. It leads to microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury due to endothelial damage and platelet aggregation.
**Why the Correct Answer is Right**
Shigella HUS is characterized by the production of Shiga toxins (Stx1 and Stx2) by Shigella dysenteriae and other enterohemorrhagic E. coli (EHEC) strains. These toxins bind to the globotriaosylceramide receptor on endothelial cells, leading to the activation of the endothelial cell signaling pathways, resulting in cellular damage, apoptosis, and platelet activation. The resultant microvascular thrombi and endothelial damage impair kidney function.
**Why Each Wrong Option is Incorrect**
* **Option A:** Incorrect because Shigella HUS is indeed associated with acute kidney injury (AKI). AKI is a hallmark of HUS, leading to elevated serum creatinine levels, oliguria, and electrolyte imbalances.
* **Option B:** Incorrect because Shigella HUS is indeed associated with thrombocytopenia. The toxin-induced endothelial damage and platelet activation lead to platelet consumption and subsequent thrombocytopenia.
* **Option C:** Incorrect because Shigella HUS is indeed associated with microangiopathic hemolytic anemia. The endothelial damage and platelet activation lead to red blood cell fragmentation and hemolysis.
**Clinical Pearl / High-Yield Fact**
Shiga toxins can also cause neurologic complications, including seizures, coma, and even death in severe cases. Early recognition and supportive care are crucial in managing Shigella HUS.
**Correct Answer: D.**