history: My friend has chronic fatigue syndrome.  Its sad
knowledge: Chronic fatigue syndrome (CFS), also referred to as myalgic encephalomyelitis (ME), is a medical condition characterized by long-term fatigue and other symptoms that limit a person's ability to carry out ordinary daily activities.
response: That's too bad. I'm aware that this limits a person's ability to do daily activities.
history: My friend has chronic fatigue syndrome.  Its sad
That's too bad. I'm aware that this limits a person's ability to do daily activities.
Yes.  He has a lot of trouble doing even everyday things in life
knowledge: Biological, genetic, infectious, and psychological mechanisms have been proposed, but the cause is not understood.
response: The cause isn't understood, but several different mechanisms have been proposed.
history: My friend has chronic fatigue syndrome.  Its sad
That's too bad. I'm aware that this limits a person's ability to do daily activities.
Yes.  He has a lot of trouble doing even everyday things in life
The cause isn't understood, but several different mechanisms have been proposed.
Oh, really? How do they diagnose it, then?
knowledge: Diagnosis is based on a person's symptoms.
response: The ultimate diagnosis is based on a person's symptoms.
history: My friend has chronic fatigue syndrome.  Its sad
That's too bad. I'm aware that this limits a person's ability to do daily activities.
Yes.  He has a lot of trouble doing even everyday things in life
The cause isn't understood, but several different mechanisms have been proposed.
Oh, really? How do they diagnose it, then?
The ultimate diagnosis is based on a person's symptoms.
That is interesting.  Can they just treat an infection for it?
knowledge: No medications or procedures have been approved in the United States.
response: There are no medications or procedures that have been approved, yet, in the US.