This kind of thing is apparently a matter of debate among physicians, because the text I've pasted below is directly from some the experts here at Medhelp. This one's from the breast cancer forum, which looks like it's monitored/answered by people from the Cleveland Clinic. It personally makes me feel a little better because I am EXTREMELY skinny, and always have been.
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Dear pattsy: Lymph nodes are located throughout our bodys, some are closer to the surface and can sometimes be felt, particularly if a person is thin. This is common in the neck, armpits, or groin. Another time that lymph nodes can be felt is if there has been an infection. For example if a pierced ear has been infected, the lymph nodes in the neck can become a little swollen and tender. It can take a week or more for them to return to normal. So, yes, it is possible that you could be feeling lymph nodes in your armpit. There may be nothing going on in your breast. However, if they get bigger or do not go away, you should have them checked out by your physician.
Its something I was told by my doctor a few days ago and I saw it on some site just a few hours ago as well.
Are you sure? Because:
http://www.lymphoma.org.uk/support/newsletter/questiontimes/whatisalymphnode.htm
"Lymph nodes or glands are fleshy pea sized structures found in groups or chains throughout the body. The nodes in the neck, armpits and the groins are easily felt; the diagram below shows their distribution. They are linked by special lymph channels that ultimately drain into the blood going to the right side of the heart."
If you can feel nodes in your armpit something is up, doesnt mean its HIV but theyre not meant to be there if you are 100% healthy.
And from what I understand, if you're a thin person, nodes in your armpits and/or groin are often palpable in skinny people (samri, correct me if I'm wrong, because you seem a lot more knowledgeable on this than I)
There are two glands located at each side of the jugular veins that are always noticable, meaning they are big enough to feel all the time. I was told this by a doctor unless larger like an olive or bigger and they remain jelly bean size I don't think there is any worry.
Guess what? I just reported you! AGAIN! You just don't give up, do you?
Dont keep poking at them because you are only going to make them worse. The only way you can tell if your lymph nodes are swollen is to have a doctor look at them and if you are worried about HIV symptoms are not a way to tell if you are infected or not. Just have an HIV test if you had a risk. Unprotected sex anal or vaginal sharing needles or had a blood transfusion. Anything else do not worry.