Dr., I have a couple of glands in my neck that have been swollen and hard (about 1cm+) for a few years now. I have a couple of questions each relating to the other I guess. First why does HIV make them hard - what is it doing - just sitting there? Next when I spend a fair amount of time outdoors on a very cold day the gland goes down to a much much smaller size - why would this be if the HIV is still there as such?

I don't know specifically why your neck lymph nodes get smaller in the cold-- it may be due to the fact that in general cold causes tissue to contract. HIV may not just be "sitting" there-- it may be multiplying. We have learned over the years that HIV+ people will have enlargement and then regression of lymph nodes, and these changes haven't appeared to be related to anything we can point a finger to-- it just happens.