title: The real nature of "perianal haematoma".
mesh_terms: D001004:Anus Diseases / Q000175:diagnosis* / Q000209:etiology; D003937:Diagnosis, Differential; D006406:Hematoma / Q000175:diagnosis*; D006470:Hemorrhage / Q000175:diagnosis* / Q000209:etiology; D006484:Hemorrhoids / Q000175:diagnosis*; D006801:Humans; D008875:Middle Aged; D009626:Terminology as Topic