Syndrome, Munchhausen: Recurrent feigning of catastrophic illnesses. Munchhausen syndrome is a psychological disorder that is characterized by the recurrent presentation of the patient for treatment of an acute and often dire illness that is, in reality, not present. The person with Munchhausen syndrome usually gives a plausible and dramatic history. All of it is entirely false. The patient tends to go from hospital to hospital feigning medical or surgical diseases and giving false and fanciful information about their medical and social background. They may even have unnecessary surgery repeatedly, resulting for example in a "mass of scars" on the abdomen, what has been called a "gridiron abdomen." Some patients with Munchhausen's syndrome cause their own illness, as by secretly ingesting or injecting substances.