how long should Mesenteric Lymphadenitis last?

[helpjacob32]

my son has been poorly now since last July with runny tummy's 3 times a day which have slowed down to 1 a day and almost stopped completely now. But his immune system is still very weak and he keeps getting cold after cold and we cannot stop him from getting a nothing bug before he has another sore throat or is hurting his muscles again from a flu like bug. does anyone have this same experience? the hospital have said it will take time, but have expected it to be over by now, around Christmas, so are doing more tests. Just seems that we cannot protect him from the bugs of the school as when he is home, he is ok, and we can keep him at one level and at least safe and bug free. any advice would be good please? xx