Patient: the child usually urine is basically normal, but a cold will appear urine occult blood 1 +, red blood cells increase, after the cold is well one to two months urine test no red blood cells, occult blood trace, if the cold will appear again urine occult blood and red blood cells, after the cold is well, urine is basically normal, and so on and so forth. At the end of last year, I did the relevant examination, and there are several abnormal items: complement C3 0.76 (normal 0.85-1.93), anion gap 16.28 (normal 8-16), and then the normal red blood cell ratio of 15%, the abnormal red blood cell ratio of 85% (the reference range is <80%). Everything else is within the normal range. What is this disease, what treatment is needed, and is it serious? Pediatric Hospital Nephrology: First of all, urinary occult blood and hematuria are not exactly the same, because urinary occult blood for the initial screening experiment to determine hematuria a method, the impact of factors are particularly many; that is to say, occult blood is positive does not necessarily have hematuria, and on the contrary, hematuria occult blood must be positive. It is recommended to clarify whether it is true hematuria, in addition, the presence of increased red blood cells in the urine when cold, especially occult blood positive can not indicate the existence of solid lesions in the kidneys. Closely follow the urine sediment urine routine.