Which triad is associated with Hemolytic Uremic Syndrome (HUS)?

Hemolytic Uremic Syndrome (HUS) is characterized by a specific triad of clinical features: anemia, thrombocytopenia, and acute renal failure. Understanding each component of this triad is essential for recognizing and diagnosing HUS.

Anemia occurs due to the destruction of red blood cells, usually resulting from microangiopathic hemolysis, where the small blood vessels are damaged, leading to the fragmentation of red blood cells. Thrombocytopenia is present because the activation of platelets, in response to the damaged vasculature, leads to their consumption and a subsequent reduction in platelets circulating in the blood. Acute renal failure arises from the combination of hemolysis, thrombocytopenia, and the resultant insults to the renal microvasculature, often stemming from the accumulation of toxins or severe dehydration following diarrhea (common in cases linked to infectious etiologies).

The other choices do not reflect the classic presentation of HUS. While fever and rash may be present in some types of infections that can lead to HUS, they do not form part of its defining triad. Similarly, thrombocytosis (an increase in platelet count) would contradict the thrombocytopenia associated with HUS. Lastly, hemoglobin