A 60 year old man complains of tiredness, lethargy and itching that is severe after a hot bath. He also has nocturia, polyuria and nausea and vomiting. Exam: pallor, pigmentation and generalized edema. What is the single most likely diagnosis?

The key is F. CRF. [Tiredness, lethargy, itching, nausea and vomiting are common features of uremia. Increased urea excretion in chronic renal failure causes polyuria and nocturia. Pallor is due to anemia of renal failure. Increased pigmentation in CRF patients is due to an increase in melanin in the basal layer and superficial dermis due to a failure of the kidneys to execrete B-melanocytestimulating hormone. Oedema is also a common feature of renal failure].