My son, 25yrs. old, has an elevated creatine, low hemoglobin, brown urine, low rbc. he has barretts, and possible precancer cells of distal esophagus?

Chronic kidney disea: Don't worry about barrett's for now. Focus on his chronic kidney disease which is diagnosed by high creatinine & leads to anemia (low hemoglobin & rbc). He needs to be evaluated & followed by his nephrologist (kidney specialist) who will recommend medications to control risk factors & prepare him for dialysis/transplant if condition worsens.