question: dear doctor my son has just turned 4yrs old and for the past few months he has got very thin. His stools are always soft and sink to the bottom of the toilet, on occasion they are diahorea. He recently has complained of his bum being itchy and it is red. He is at nursery school and I know he is active and growing but has always had a good appetite and we would eat healthy home cooked meals, however the food in school is somewhat processed and I think at times he does not eat a lot of his dinner in school and this may be a contributing factor in the weight loss. Also about 2 weeks ago he seemed to be having bad nightmares, sweating/fever and his body was twitching a bit. He was like that for 3 nights running and then it stopped. he has night sweats regularly but this was more like a fever. I am concerned about his weight, and was wondering if you would have any advice, or would this give you an idication of any possible diagnosis?