Urinary occult blood with a plus sign can be seen in the following cases: the first is physiological factors, such as heavy physical activity, heavy physical labor, and the occurrence of upper respiratory tract infections or acute gastroenteritis and other related diseases, in this case, the treatment is to take adequate rest and actively treat diseases unrelated to urinary routine; the second is the possible occurrence of IgA nephropathy or other types of nephritis, in addition to occult blood In this case, in addition to a plus sign of occult blood, it is often combined with a positive proteinuria, and the treatment requires a color Doppler ultrasound-guided kidney aspiration, as well as the continuation of glucocorticoids and immunosuppressive drugs; the third type is the combination of urinary tract infection or stones, and sometimes malignant tumors of the kidney may also show a plus sign of occult blood.