Munchausen Syndrome 

The medical case literature provides compelling documentation of patients who have intentionally exaggerated, feigned, simulated, aggravated, or self-induced an illness or injury for the primary purpose of assuming the sick role (now known as Munchausen syndrome). These occurrences were documented in the modern medical literature as early as the mid 19th century, and were identified as a distinct psychiatric disorder in 1951 by Asher, who coined the term Munchausen syndrome. He selected the Munchausen eponym because of the celebrated stories of a Prussian cavalry officer named Baron von Münchhausen, who told fantastical stories about his military exploits, and who later was mocked by Rudolph Erich Raspe in his 1785 book, The Adventures of Baron Munchausen.

Although many health professionals use the term to describe all persons who intentionally feign or produce illness to assume the sick role, Munchausen syndrome is not included as a discrete mental disorder in the World Health Organization's International Statistical Classification of Diseases, 10th Revision (ICD-10) or in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR)^[1] . In both systems, the official diagnosis in these cases is factitious disorder (F68.1 in the ICD-10; 300.16 or 300.19 in the DSM-IV-TR). Nevertheless, numerous experts have identified a distinct subset of patients with factitious disorder for whom they reserve the term Munchausen syndrome.

The DSM-IV-TR diagnostic criteria for factitious disorder are as follows:

1. The patient intentionally produces or feigns physical or psychological signs or symptoms.
2. The motivation for the behavior is to assume the sick role.
3. External incentives for the behavior are absent.

The following subtypes are specified in the DSM-IV-TR.

1. Patients with primarily physical signs and symptoms (300.16)
2. Patients with primarily psychological signs and symptoms (300.19)
3. Combined subtype (300.19)

The subtype referred to as Munchausen syndrome lacks its own code but can be distinguished by the following characteristics:

• The factitious illness behavior is particularly chronic and severe and may be practiced to the exclusion of most other activities. The signs and symptoms of illness or injury are intentionally produced through medically dangerous manipulations of the patient's body (eg, self-inflicted infection, superwarfarin ingestion), thereby virtually guaranteeing hospitalization. These patients willingly, if not eagerly, submit to invasive interventions such as surgery.
• Peregrination, also commonly called itinerancy in the professional literature, is observed. The patient may move from hospital to hospital, town to town, and even country to country to find a new audience once his or her ruse is uncovered.
• Pseudologia fantastica is present in classic cases. The patient makes false claims about distinguished accomplishments, educational credentials, relations to famous persons, etc.

Some authors invoke additional diagnostic elements in addition to the triad described above. For instance, in relation to peregrination and pseudologia fantastica, the patient may use aliases or adopt false identities. Patients with Munchausen syndrome have little or no significant social contact with anyone other than health care professionals.

The published literature on factitious disorder is almost entirely limited to case reports and clinical guidelines based on unsystematic clinical observations (the subjectivist approach). Apparently, only 2 empirical studies of persons with Munchausen syndrome exist. The lack of systematic research is attributable to the reluctance of these patients to admit to their deceit or to cooperate with psychiatric investigations.

The literature on factitious disorder and Munchausen syndrome is not based on scientifically established facts so much as anecdotal and single case reports. In either scenario, the terms may have been misapplied. A peculiarity of the case literature on factitious disorder is that it reflects a bias toward the more extreme cases and those that pose the greatest medical danger, ie, cases that almost always involve induction of actual severe illness by the patient (eg, suppression of bone marrow through surreptitious use of chemotherapy medications).

Case study

Ms. A, a 51-year-old woman, presented to a specialized outpatient agency to ask for help in coping with her deafblindness. She reported having Usher syndrome, an autosomal recessive disease involving hearing loss and retinitis pigmentosa. On examination, Ms. A was well-groomed and ambulated with a walker. She mentioned multiple medical problems, including multiple sclerosis, cardiac disease, diabetes, hypertension, sleep apnea, glaucoma, and history of a traumatic brain injury. It was apparent in face-to-face and telephone contacts that Ms. A was able to hear and understand without difficulty; however, she requested that sign language be used when communicating with her in person. She hoped through treatment to obtain "support in coping with my Usher syndrome." She did not request services such as home assistance, additional physical aids, or treatment for her symptoms, although a variety of services related to her blindness were offered.

During subsequent interviews and examinations, additional irregularities emerged. For instance, she said that she lived with her husband of 23 years but could not state where he worked or what kind of work he performed. She reported a history of working as a sign language interpreter, but the quality of her sign language was too poor for her to have functioned in this role, and her "blindness" would have precluded it. She did not appear to have restricted visual fields on observation of her ambulation, and she did not scan the environment as people with limited peripheral vision do. Formal fields testing resulted in inconsistent responses. Ms. A had been given hearing aids elsewhere based on subjective audiologic testing, but subsequent otoacoustic emissions tests had shown no more than a mild hearing loss in one ear. She rejected testing that could have ruled in or out an auditory processing disorder.

Outside records were limited because the patient typically claimed that she could not remember doctors' names. A formal ophthalmologic examination was benign, but the patient had joined a diabetic retinopathy group. An electroretinogram was normal. The patient's primary physician affirmed that she was not diabetic and cardiac work-ups had been benign. A neurologist had ruled out multiple sclerosis. Sleep apnea, glaucoma, and traumatic brain injury could not be documented. Ultimately, it was explained to Ms. A that she did not have Usher syndrome. She then announced that she actually had Leber syndrome, a hereditary mitochondrial disorder with central nervous system manifestations that can include deafblindness. She clearly did not have this condition. She also reported that she would be transferring her care to another center for deaf people and would see a deaf therapist using American Sign Language. She did not return to the agency.

No brain defect or dysfunction has been established to cause the behavior patterns that characterize Munchausen syndrome or factitious disorder more generally. A study of 5 cases of Munchausen syndrome suggested neurocognitive deficits. One case study reporting on the results of single-photon emission computed tomography (SPECT) analysis found hyperperfusion of the right hemithalamus in a patient with factitious disorder.^[2] It remains to be seen whether these results are replicable in larger samples, and if so, how these brain dysfunctions are linked to factitious illness behavior.

Frequency

United States

Epidemiological data on factitious disorder are scarce. Patients with factitious disorder are generally not open and honest about their medical deceptions. Because epidemiological studies of the general population rely on respondents' self-reports, estimating the prevalence of factitious disorder in the general population is impossible. Patients with Munchausen syndrome, who may not have a fixed address or a telephone number, are unlikely even to be recruited for such studies.

Studies of medical patients suggest that the prevalence of factitious disorder is probably in the range of 0.2-1% of hospital inpatients.^{[3, 4]} Although patients with Munchausen syndrome have appeared with almost every medical condition, the prevalence is particularly high in a few select settings. These include patients who present with persistent rashes and nonhealing wounds, unexplained anemia, neurological problems, endocrine-related problems, hematuria, and joint and connective-tissue symptoms.

As might be expected, the prevalence is even higher among patients with unexplained or intractable medical complaints. For example, 9.3% of a sample of persons with fever of unknown origin were determined to have simulated or produced fevers. Another study found that an astounding 40% of brittle diabetics altered their medication compliance or diet to intentionally produce diabetic instability.

International

No epidemiological studies address the rate of factitious disorder or Munchausen syndrome in countries and cultures outside the United States and western Europe. Case reports indicate that the diagnosis of factitious disorder has been made in eastern Europe, Mediterranean countries, Asia, Africa, and South America.

Mortality/Morbidity

Four features of factitious disorder that are particularly prominent in Munchausen syndrome significantly increase morbidity and mortality risk.

• The first is dangerous manipulations of the patient's own body, including the ingestion of chemical toxins, self-infection, aggravation of wounds, and so on. Although patients with Munchausen syndrome are generally medically knowledgeable and sophisticated, their manipulations sometimes result in unintended serious injury, permanent disability, or death.
• Second, the patients place themselves at risk for iatrogenic illness and injury by repeatedly engaging in deceptions that cause medical care providers to perform risky diagnostic and treatment procedures. In some cases, the resultant damage is part of the patient's plan. For example, a patient who pretends to have a malignancy may desire the adverse effects of chemotherapy, or a patient may simulate adrenal gland dysfunctions with the intention of having an adrenal grand removed. In other cases, the iatrogenic damage results from unintended medical accidents such as adverse medication effects, allergic reactions, or surgical complications. Because patients with Munchausen syndrome subject themselves to so many medical procedures, their lifetime risk of experiencing an unintended adverse medical event is many times greater than that of the average person.
• Third, patients with Munchausen syndrome frequently provide incomplete or false medical history information that intentionally or accidentally causes increased morbidity or mortality risk. For example, they may experience dangerous adverse medication effects because they withhold information about known drug allergies, or they may suffer surgical complications because they fail to inform the medical staff that they have taken anticoagulant medications.
• Finally, although patients with factitious disorder or Munchausen syndrome are more likely than typical patients to claim illness or injury, they are no less likely than anyone else to actually become ill or injured. However, for genuinely ill patients with a known history of factitious medical complaints, medical staff may delay or withhold necessary tests and treatments to minimize unnecessary iatrogenic risks and to avoid reinforcing patients' inappropriate behavior. As with the boy who cried wolf in Aesop's famous tale, patients with Munchausen syndrome may be unable to mobilize the serious attention of medical staff when they truly need it.

Race

The case literature clearly shows that most patients with Munchausen syndrome are white. In the absence of demographic data describing the racial/ethnic composition of the patient populations in which these cases were identified, it is currently impossible to know whether race represents a significant risk factor.

Sex

Among Munchausen syndrome cases described in published reports, there are many more cases of male patients than female. This observation is particularly noteworthy in light of the fact that the literature on factitious disorder and the somatoform disorders suggests a much higher prevalence among women than men.

Age

The published cases of Munchausen syndrome generally describe patients aged 30-50 years. Infants and toddlers whose medical problems reflect intentionally produced signs of illness or injury are typically abused by a parent or other custodial adult (see Munchausen Syndrome by Proxy). The diagnostic picture is much less clear in cases of older children and young adults, who may be feigning illness on their own but who also may be encouraged to adopt the sick role by a parent or other custodian.