4 Year Old With HSP. Burning In The Feet, Arms. Muscle Weakness, Vitamin Deficiency, Nose Bleeding And Low Iron. Concerned

Hi my son has HSP now for nearly 4 years, he is only 9 years old, for a year and half he hasn,t been too well, burning feeling in feet legs face arms and has had weakness in his muscles, the doctors say this is not HSP this is something different, but they do not no what it is, he has had alot of tests done, my son has had anticereme b, tryglyceres levels at the higest level of 6.4 , cardiac enzyme nearly 3000 , vitamin D defency ,low in Iron, blockage in the large bowel, bleeding of his nose , and now he is seeing the colours blue and rainbow colours, I am very worried mum , can you help, thank you x