An AIDS patient experiences progressive weakness of extremities over weeks, distal sensory deficits for pinprick and vibration, slow nerve conduction, but EMG shows no denervation. What is the likely diagnosis?
A) Guillain-Barré syndrome
B) Chronic inflammatory demyelinating polyneuropathy (CIDP)
C) Amyotrophic lateral sclerosis (ALS)
D) Peripheral neuropathy