The reasons for the residual fecal matter after wiping include anal surgery, hemorrhoids, rectal cancer, etc. 1. Anal surgery: when the patient has just finished anal surgery, the phenomenon of residual fecal sludge occurs due to poor anal closure after the surgery. 2. Hemorrhoids: if the patient has hemorrhoids, the protruding hemorrhoids can lead to poor anal closure, thus residual fecal residue. 3. Rectal cancer: when the patient has rectal cancer, the tumor will oppress the anus and lead to anal deformity, which may also lead to the phenomenon that there is still fecal residue after wiping the stool. There may also be other reasons for the scum of stool after wiping, if the symptoms continue to be unrelieved, it is recommended to consult a doctor in time, under the guidance of the doctor to clarify the cause of the disease and targeted treatment.