Factitious Disorder Imposed on Another (Munchausen by proxy)

Updated: Nov 11, 2015
  • Author: Guy E Brannon, MD; Chief Editor: Glen L Xiong, MD  more...
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Practice Essentials

Factitious disorder imposed on another (formerly factitious disorder by proxy) has as its cardinal characteristic the production or feigning of physical or psychological symptoms in another person, usually a child or adult under the care of the person with the disorder. It is currently understood as including the condition commonly known as Munchausen syndrome by proxy (MSBP).

Signs and symptoms

Common presentations of factitious disorder imposed on another (including MSBP) include the following:

  • Bleeding

  • Seizures

  • Recurrent apparent life-threatening events

  • Poisoning

  • Apnea

  • Central nervous system (CNS) depression

  • Diarrhea and vomiting

  • Fever, either feigned (via falsification of chart records) or actual

  • Rash

  • Hypoglycemia

  • Hyperglycemia

  • Hematuria or guaiac-positive stools

  • Multiple infections with varied and often unusual organisms

Warning signs that raise the possibility of this disorder include the following:

  • Unexplainable, persistent, or recurrent illnesses

  • Discrepancies among the history, clinical findings, and child’s general health

  • A working diagnosis of a rare disorder

  • Symptoms and signs that occur only in the mother’s presence

  • A mother who is extremely attentive and always in the hospital

  • A child who is frequently intolerant of treatment

  • A mother who appears less worried about her child’s illness than about the medical staff

  • Seizures that do not respond to appropriate therapy

  • Families in which unexplained sudden infant death syndrome (SIDS) occurs

  • A mother with previous medical or nursing experience or an extensive history of illness

During clinical assessment of the victim in a case of suspected MSBP, clinicians should ask themselves the following questions the following questions:

  • During clinical assessment, is the child’s medical status consistent with the mother’s description?

  • Does objective diagnostic evidence support the child’s reported medical condition?

  • Has any staff member, including the pediatrician, witnessed the symptoms?

  • Do negative test findings reassure the mother?

  • Is treatment being provided to the child primarily because of the mother’s persistent demands?

See Presentation for more detail.


Evaluation must be based on specific symptoms, with specific tests aimed at detecting the potential method by which the factitious symptoms are being induced.

Laboratory tests that may be considered include the following:

  • Complete blood count (CBC)

  • Urine toxicology screening

  • Chemistry panels

  • Drug levels for suspected poisoning agents (eg, aspirin, acetaminophen, and anticonvulsants)

  • Cultures

  • Coagulation tests

  • Sequential multiple analysis

  • Assays for rapid plasma reagent, thyroid-stimulating hormone, and thyroid function

  • DNA typing

Other studies that may be helpful, depending on the clinical circumstances, are as follows:

  • Computed tomography (CT)

  • Magnetic resonance imaging (MRI)

  • Psychological testing

  • Electroencephalography (EEG)

  • Electrocardiography (ECG)

If no physical cause of the symptoms is found, a retrospective review of the child’s medical history, with careful consideration of the family history and the mother’s medical history might provide clues suggesting MSBP.

See Workup for more detail.


Treatment of factitious disorder imposed on another involves treating the following:

  • The victim (most often a child), who commonly receives an abuse diagnosis

  • The perpetrator (typically a parent, most frequently a biologic mother), to whom the actual diagnosis of factitious disorder imposed on another or MSBP applies

  • The family

A stepwise approach to the management of this disorder may be summarized as follows:

  • Obtain and verify the victim’s and the family’s pertinent medical and social histories, previous hospitalizations, and medical records

  • Interview the other partner and any other family members alone, when the suspected perpetrator is not present

  • Admit the child to the hospital to observe the parent-child interaction, closely observe the suspected perpetrator, and determine the temporal relation between the symptoms and the perpetrator’s presence

  • Consider separating the child from the suspected perpetrator to protect the child and to confirm cessation of the child’s symptoms in the perpetrator’s absence

  • During hospitalization and under close observation, obtain the necessary body-fluid samples for toxicology screens and any other relevant investigations; if a multidisciplinary team agrees on the procedure, hidden cameras can be used to record the interactions of the child and the suspected perpetrator in the hospital setting

  • Arrange for social service, psychological, and psychiatric evaluations of the child and the suspected perpetrator

  • Assemble a team or task force to examine the records objectively before the suspected perpetrator is confronted

  • Inform the local child protection and law enforcement agencies before confronting the suspected perpetrator

  • After the suspected perpetrator has been informed of the diagnosis, remove the child and other siblings at risk; for adequate protection, relocate the child to a place that is inaccessible to the suspected perpetrator

  • Recommend short-term and long-term psychological and psychiatric treatment for the suspected perpetrator

  • Verify that long-term close monitoring will be provided by the court; this is essential for ensuring the child’s safety

  • Ensure that relevant reunification criteria are met before the court considers reunification

See Treatment for more detail.



Factitious disorder imposed on another (formerly factitious disorder by proxy) has as its cardinal characteristic the production or feigning of physical or psychological symptoms in another person, usually a child or adult under the care of the individual with the disorder. Secondary or external factors are not present, and the person often lacks other mental or physical illnesses. Although this disorder is not uncommon, it can be difficult to detect and confirm. [1]

In the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), [2] the diagnosis of factitious disorder imposed on another includes the disorder originally known as Munchausen syndrome by proxy (MSBP), [3] a term that continues to be commonly used in clinical practice. MSBP is a covert, potentially lethal, and frequently misunderstood form of abuse (typically, child abuse).

In 2002, the term pediatric condition falsification (PCF) was introduced by the American Professional Society on the Abuse of Children (APSAC) to describe the condition in the abused child. APSAC defined MSBP as comprising factitious disorder by proxy (as the disorder was then known) in the perpetrator and PCF in the victim.

In factitious disorder imposed on another, the caretaker voluntarily and consciously simulates or induces symptoms of an illness and then takes the child or other person to seek medical attention, disavowing knowledge of the source of the problem. The deception may arise from anger or a desire for attention, which is satisfied by having a relationship with a practitioner.

Most of the symptoms are physical complaints; feigning of mental symptoms occurs to a lesser extent. Physical presentations include vomiting, diarrhea, respiratory arrest, asthma, seizure, recurrent conjunctivitis, clumsiness, syncope, fever, infection, bleeding, failure to thrive, or electrolytic disturbance.

Clinicians are trained to elicit the history of a sick child from his or her parents. This standard approach carries extra risk in this setting. Typically, a parent with the disorder—usually the biologic mother—recounts serious but vague symptoms. This information may result in the performance of many laboratory tests and other procedures, including surgery. Out of fear, the child does not contradict the information. The outcome for the child could be serious injury or even death.

Inconsistent illness descriptions, improbable physical findings, or inexplicable test results should raise the suspicion of factitious disorder imposed on another. For example, polymicrobial sepsis in a central line is extremely rare and should elicit consideration of the possibility of tampering. As another example, finding carbamazepine in the blood of a patient to whom the drug was not prescribed or finding a high level in a patient in whom it was discontinued should suggest possible MSBP.

A multidisciplinary team approach is mandatory to confirm the diagnosis and protect the victim. Long-term psychiatric follow-up is necessary for both the child and the perpetrator. Educating healthcare providers about the disorder and establishing local task forces may facilitate timely diagnosis and management. The health care system may, unknowingly, play a partial role in the perpetration of unnecessary testing and treatments. Appropriate awareness of MSBP by medical providers may prevent or minimize potential harm to victims.

Diagnostic criteria (DSM-5 and American Academy of Pediatrics)

In DSM-5, factitious disorder is divided into the following 2 types [2] :

  • Factitious disorder imposed on another (formerly factitious disorder by proxy; MSBP)

  • Factitious disorder imposed on self (more chronic and severe forms of which are commonly labeled as Munchausen syndrome [4] )

When an individual falsifies illness in another (eg, a child, an adult, or a pet), the diagnosis is factitious disorder imposed on another. The specific DSM-5 criteria for factitious disorder imposed on another are as follows [2] :

  • Falsification of physical or psychological signs or symptoms, or induction of injury or disease, in another, associated with identified deception

  • The individual presents another individual (ie, the victim) to others as ill, impaired, or injured

  • The deceptive behavior is evident even in the absence of obvious external rewards

  • The behavior cannot be better explained by another mental disorder, such as delusional disorder or another psychotic disorder

This diagnosis is applied to the perpetrator, not the victim; the victim may be given an abuse diagnosis. For example, the term medical child abuse (MCA) was proposed by Roesler and Jenny to describe the excessive, unnecessary, and harmful medical or surgical treatments unknowingly imposed on the child at the instigation of a caregiver. [5]

For purposes of comparison, the specific DSM-5 criteria for factitious disorder imposed on self are as follows [2] :

  • Falsification of physical or psychological signs or symptoms, or induction of injury or disease, associated with identified deception

  • The individual presents himself or herself to others as ill, impaired, or injured

  • The deceptive behavior is evident even in the absence of obvious external rewards

  • The behavior cannot be better explained by another mental disorder, such as delusional disorder or another psychotic disorder

In both types of factitious disorder, the duration is specified as either a single episode or recurrent episodes (≥2 events of falsification of illness or induction of injury).

According to the American Academy of Pediatrics Committee on Child Abuse and Neglect, the healthcare worker must substantiate the credibility of the signs and symptoms, determine the necessity and benefits of the medical care, and question who is the instigator of the evaluations and treatments. To make the diagnosis of MSBP, the presence of the following 2 factors must be established:

  • Harm or potential harm to the child from excessive intervention

  • A caregiver who is fabricating illness or pursuing unnecessary treatment; the motivation of the perpetrator is not important in diagnosing the abuse

The latency period between the start of abuse and its discovery can be relatively long. Several barriers often delay the timely detection and confirmation of MSBP, including the following:

  • Failure to consider MSBP in the differential diagnosis

  • Unfamiliarity of MSBP on the part of pediatricians and other healthcare providers [6]

  • Uncertainty with regard to differentiating parental anxiety or concerns from a pathologic seeking of healthcare

  • Tendency of the physician to believe the medical history the mother provides

  • Ability of the mother to present a highly persuasive and compelling medical history

  • Involvement of several physicians, often in different hospitals and sometimes numerous cities and states

  • Fear of making a false accusation and its subsequent legal repercussions

  • Lack of collaboration between medical, legal, and child-protection agencies

  • Reluctance to separate the child from the family to evaluate the child’s medical condition without the mother’s involvement

Various authors have suggested other criteria for identifying MSBP. In 1998, Parnell and Day developed 18 guidelines based on their experience and the recommendations of other authors. [7] These guidelines were divided into 3 categories according to specific features identified in the victim, the perpetrator, and the family—including many of those described above. A number of institutions have used hidden video cameras to record the child in the hospital in an effort to obtain evidence that might confirm the diagnosis. [8, 9]



Most cases of factitious disorder imposed on another have been reported in the pediatric literature. The exact pathophysiology is unknown.

A study from 1992 suggested that parental responses to children occupy a continuum. [10] At one end of the continuum is the parent who exhibits classic neglect, disregarding symptoms in a child who is truly ill. At the other end is the parent who fabricates or generates factitious symptoms in a child who is otherwise healthy. In between are the parents who are appropriately concerned about a child’s symptoms and who make appropriate efforts to seek care for the child.

Parents with MSBP who inflict abuse on their children have psychological problems that warrant professional intervention. In 1997, Bryk published a detailed description of the prolonged and horrifying abuse she sustained at the hands of her own mother. [11] This instructive article is recommended reading for any medical professional who may come into contact with the victims of this particularly insidious form of abuse.

A number of theories for the pathogenesis of factitious disorder imposed on another have been postulated. The psychodynamic literature emphasizes a reaction to loss or a way to obtain attention and nurturing, a way to feel powerful, or a way of just acting out as possible explanations. Some investigators offer unspecified brain dysfunction as an explanation. In this theory, the mother may have experienced abuse as a child, or she may be simply rejecting her childhood for some unknown reason.

Bass et al suggest that a chronic somatic symptom disorder or factitious disorder is present in mothers who cause their children to be ill. In their study, half of the mothers exhibited pathologic lying; for some, this dated back to adolescence and often continued into adult life. The authors suggest that any psychiatrists who encounter women with chronic somatic symptom disorder or factitious disorders should be alert to the impact of these illnesses on any dependent children, especially if evidence suggests lying from an early age. [12]



Research has not yet established a single cause for factitious disorder imposed on another. Major causes may include the following:

  • Maternal history of abuse or reported abuse

  • Rejection of the child

  • Use of the child to maintain control

  • Pathologic relationship with the child

  • Psychological reward received from the medical community because of the sick child

The following psychiatric comorbidities may be present:



United States statistics

The incidence and prevalence of factitious disorder imposed on another in the United States, though not precisely known, [13] are almost certainly higher than was once estimated. In 1991, Schreier and Libow surveyed 880 pediatric neurologists and 388 pediatric gastroenterologists in the United States, with return rates of 21.8% and 32.4%, respectively. [14] Among physicians who responded, 212 reported contact with 192 suspected and 273 confirmed children exposed to MSBP.

It is estimated that approximately 625 cases of poisoning and suffocation attributable to MSBP can be expected in the United States each year. Schreier had predicted an incidence of 1200 new cases per year in the United States, but this number was subsequently revised downward, to about 200 per year. This estimate basically refers to clinically significant cases diagnosed or treated in a hospital setting and may underestimate the number of cases seen in outpatient clinics.

International statistics

Factitious disorder imposed on another is increasingly recognized and reported worldwide. More than 700 cases from 52 countries have been reported in the literature; however, these reflect only the most severe cases and cases that have been substantiated. The true overall prevalence is unknown.

One group found that 1% of children with asthma had been subjected to MSBP. [15] In another report of children with food allergies, 16 of 301 children (5%) had been subjected to MSBP. [16]

In an English town with a population of 200,000, 39 cases of intentional suffocation of children were reported over 20 years (1 case per 25,000 population). [17] A survey by the British Pediatric Association Surveillance Unit found 128 cases of reported MSBP in the United Kingdom and Ireland over a period of 2 years, with an incidence of 2.8 cases per 100,000 children younger than 1 year and an incidence of 0.5 cases per 100,000 children younger than 16 years. [18]

Age-related demographics

The abusive behavior characteristic of MSBP commonly starts early in the victim’s life; infants and young children are those most frequently exposed to MSBP. According to Rosenberg, the median age of the child at the time of MSBP diagnosis is 39.8 months, though children older than this have also been affected by caretakers with this condition. [19] McClure et al reported a median victim age of 20 months at diagnosis, with a distribution skewed toward younger individuals. [18]

A report by Meadow found that suffocation began between the first and third months of life and lasted 6-12 months or until the patient died. [20] In a review of 451 published cases, Sheridan found that affected children were usually younger than 4 years. [21] Awadallah et al reported a 14-year-old MSBP victim and 9 victims older than 6 years who were referred to child protective services between January 2001 and June 2003. [22] In their literature review, they also found 42 victims reported from 1966 to 2002.

Siblings may receive the same abuse that the reported MSBP victim receives, and from the same parent. According to Rosenberg, 8.5% of siblings were abused. [19] In a series of 27 infants who were suffocated, 48% had a sibling who allegedly died of sudden infant death syndrome (SIDS). [20] A survey of pediatric neurologists and gastroenterologists found that almost 25.8% of children who were abused had siblings who also were abused.

In a survey of 83 index cases of MSBP, 15 children had 18 siblings who previously died, and 5 of these deaths were classified as SIDS. In another report, 28 children subjected to MSBP had 41 siblings, 12 of whom died suddenly; 11 deaths were classified as SIDS, and 1 was attributed to gastroenteritis. Five parents admitted to killing 9 of the siblings. A meta-analysis of 451 cases of MSBP with 210 siblings revealed that 61% of the siblings had symptoms and 25% had died. [21]

In a series of 135 victims reported by Feldman et al from 1974 to 2006, 31 of 34 children had siblings who were also victimized resulting; 6 of these siblings died. [23]

Sex-related demographics

Boys and girls are exposed to MSBP with approximately equal frequency.

In more than 95% (perhaps as many as 98% [24] ) of cases of MSBP, the mother is the perpetrator of the child’s illnesses. In a review by Sheridan, mothers were the perpetrators in 76.5% of 451 cases, and fathers were the perpetrators in 6.7%. [21] In a series of 135 patients reported by Feldman et al, The mother was the perpetrator in almost all of the cases. [23]

Few publications have reported fathers as the primary perpetrators in substantiated cases of MSBP. In these cases, the fathers did not fit the devoted-parent profile but were described as emotionally disturbed and mentally unstable. Other reported perpetrators in cases of MSBP have been stepparents, grandparents, foster parents, and caregivers (eg, babysitters).

Race-related demographics

To date, no racial or ethnic predilection for this condition has been determined. However, most of the mothers in published reports have been white.



Generally, prognosis in factitious disease imposed on another depends on patient characteristics. Patients with a good prognosis have the following characteristics:

  • They are able to assume responsibility for their behavior

  • They can improve their coping skills

  • They can place their child’s needs above their own

Patients with a poor prognosis may exhibit the following signs:

  • They demonstrate a high degree of denial

  • They are uncooperative with therapy

  • They may have a personality disorder

Reported morbidity and mortality vary considerably, ranging from infection of unknown origin to unexplained death. The incidence of death and serious medical complications is not precisely known. Mortality ranges from 9% to 31% among index cases, with most investigators reporting a mortality of 9-10%. In a review of the literature, Sheridan reported a 6% mortality and a 7.3% long-term injury rate for index cases. [21]

Morbidity may result either from the abuse or from multiple interventions performed by unwitting physician facilitators. McClure et al reported that 122 of 128 abused children were hospitalized as a result of abuse; of the 128, 119 received unnecessary invasive interventions, 45 had major medical illnesses, 31 had minor physical ailments, and 8 died. [18] In a survey of 51 clinics treating infant apnea, 54 of 20,090 children had been subjected to MSBP. [25] Cardiopulmonary resuscitation was performed in 21 of the 54, and 24 were hospitalized.

Children subjected to MSBP present not only with induced physical ailments but also with fabricated psychological symptoms. Like those receiving other types of abuse, children subjected to MSBP can have long-term emotional and psychological disorders.

McGuire and Feldman described 6 children who had behavioral problems, including feeding disorders in infants; withdrawal, hyperactivity, and oppositional behaviors in preschoolers; and conversion symptoms in older children and adolescents. [26] Older children often tolerated and cooperated with their parents in their own abuse and fabricated medical illnesses of their own.

Bools et al reported the outcome of 54 children aged 1-14 years who were subjected to MSBP. [27] Several of them had behavioral problems, such as emotional and conduct disorders, achievement problems, nonattendance at school, fears and avoidance of specific places or situations, sleep disturbances, or features of posttraumatic stress disorder (PTSD). Boys had more disturbances than girls.

In this report, [27] most of the children who remained with their mothers were exposed to repeated fabrication or were described as having other concerns. Children with unacceptable outcomes were older than others at the time of abuse and were more likely to have siblings who had also been subjected to abuse.

Libow reported the results of a 33-item questionnaire administered to 10 adults who identified themselves as survivors of MSBP during childhood. [28] At the time of abuse, the respondents felt unsafe and unloved by their parents. As children, they had emotional stress and serious depression problems. They also reported problems with school and education as a result of absenteeism, lack of attention, or anxiety. As adults, they had insecurity, low self-esteem, depression, and symptoms of PTSD.


Patient Education

It is important to educate the patient, family, and medical staff about factitious disorder imposed on another. Patient education focuses on imparting techniques for helping patients improve their coping and stress-management skills. Family education regarding patterns of this disorder in previous generations of the family is necessary for effective treatment. If other children are present in the home, they should be evaluated for possible abuse as well.

In particular, family members should be educated about healthy ways for the patient to express his or her anger. They should be encouraged to allow the patient to express anger appropriately and not to consider such expression a hindrance to the recovery process.

For patient education resources, see the Children’s Health Center and the Mental Health and Behavior Center, as well as Child Abuse and Munchausen Syndrome. In addition, the following Web sites may be helpful:


Ethical and Legal Issues

The Federal Child Abuse Prevention and Treatment Act defines MSBP as “[a]ny recent act or failure to act on the part of a parent or caretaker, which results in death, serious physical or emotional harm, sexual abuse, or exploitation, or an act or failure to act which presents an imminent risk of serious harm.” MSBP is difficult to prove; patients are typically not caught, and cases are usually based on circumstantial evidence.

Where factitious disorder imposed on another is suspected, the law requires physicians to notify the authorities, which may include the following:

  • Child Protective Services

  • Social Services

  • Hospital Risk Management department

  • Local law enforcement agencies

In addition, steps for the immediate protection of the child must be initiated. Protection may involve removal of the child from the home, at least until the situation can be completely assessed. A court order may be needed to remove the child from the perpetrator.

Once protective measures are in place, the perpetrator should be confronted with the evidence. This individual will almost certainly deny the charge and will attempt to remove the child from the hospital. Criminal prosecution of the perpetrator may also be necessary.

Evaluation should not be limited to the child involved but should also include his or her siblings. Psychotherapy should be offered to the mother, the affected children, and the family. Pharmacotherapy may be appropriate when the mother has comorbid psychiatric conditions that are amenable to treatment. The family requires careful long-term monitoring, especially because of the danger that the mother could move her family and seek to perpetrate such behavior in a new location.