A 20 year – old male has features of acute renal failure. Blood examination shows thrombocytopenia and Hb-10 gm%. Likely cause is –
**Core Concept**
Thrombotic Thrombocytopenic Purpura (TTP) is a rare blood disorder characterized by the formation of blood clots in small blood vessels throughout the body. These clots can lead to a decrease in platelets, anemia, and acute kidney injury.
**Why the Correct Answer is Right**
The likely cause of acute renal failure in this patient is TTP, which is a classic presentation of this disorder. TTP is caused by a deficiency of ADAMTS13, an enzyme responsible for cleaving von Willebrand factor (VWF), a protein involved in blood clotting. Without sufficient ADAMTS13, VWF builds up and forms large platelet-rich thrombi, leading to thrombocytopenia, microangiopathic hemolytic anemia (as evidenced by the patient's Hb of 10 gm%), and renal failure.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not likely, as HUS (Hemolytic Uremic Syndrome) typically presents with a more severe thrombocytopenia and a higher degree of renal impairment.
**Option B:** This option is incorrect as it doesn't match the clinical presentation of TTP, which typically involves thrombocytopenia, microangiopathic hemolytic anemia, and renal failure.
**Option C:** This option is incorrect as it doesn't account for the thrombocytopenia and microangiopathic hemolytic anemia seen in TTP.
**Clinical Pearl / High-Yield Fact**
A classic mnemonic to remember the pentad of TTP is: Thrombocytopenia, Microangiopathic Hemolytic Anemia, Renal Failure, Fever, and Neurological symptoms (such as confusion or seizures).
**Correct Answer:** C.