I thought that ds1 had threadworms when he started scratching a lot. It wasn't diagnosed by a doctor but we treated the whole family. Now he's stopped scratching but both ds's have redness around the anus - i can tell because ds2 is in nappies, and although ds1 won't let me look i've spotted the same around his. It's not really like nappy rash, it's quite a vivid red sore looking circle, and I've been putting loads of sudocrem etc on and it's not getting better. We've been extra careful on hygene (never had any problems before) so what could it be?