Munchausen by proxy

**Terminology** - DSM-5: Factitious Disorder Imposed on Another (FDIA). Formerly called Munchausen syndrome by proxy (MSBP). - Pediatric term: Medical child abuse (or "pediatric condition falsification"). This emphasizes harm to the child rather than the perpetrator's motives. - Munchausen syndrome is Factitious Disorder Imposed on Self. The patient fabricates or induces their own illness.

**Definition and key features** - A perpetrator falsifies illness in another person, who is usually a child but can be an elderly or dependent adult or a pet. - The deception is present with or without an obvious external reward. - The motive is psychological: the perpetrator assumes the sick role by proxy and gains attention, sympathy, and admiration. The motive is not material gain, which would be malingering. - The diagnosis is applied to the perpetrator, not the victim. The victim is diagnosed with child abuse.

**Epidemiology and perpetrator profile** - The perpetrator is most often the biological mother (about 75-95% of cases). - Often the mother has a healthcare background or knowledge of medicine. - She is often described as overly attentive, appearing devoted, and forming close relationships with staff. - She may have a personal history of factitious disorder, somatic symptom disorder, personality disorder (e.g., borderline or histrionic), or childhood abuse. - The victim is typically young (often <6 years), and the father is often absent or uninvolved.

**Methods** - Fabrication: false history, falsified lab samples (e.g., adding blood to urine). - Exaggeration of real symptoms. - Induction: suffocation or smothering (apparent life-threatening events), poisoning or drug administration (e.g., laxatives causing diarrhea, insulin causing hypoglycemia, ipecac causing vomiting, salt causing hypernatremia, anticoagulants causing bleeding), or tampering with lines.

**Red flags** - Symptoms are persistent, recurrent, or unexplained, and they do not fit any known disease. - Symptoms occur only when the caregiver is present, and they resolve with separation. - Multiple hospitalizations, multiple specialists, and extensive negative workups. - Failure to respond to usual treatment. - A caregiver who seems unusually calm or eager for invasive procedures. - A sibling with unexplained illness or death in the family history. - Lab findings that are discordant with the clinical picture (e.g., high insulin with low C-peptide suggests exogenous insulin).

**Diagnosis and management** 1. Thorough record review. Obtain the complete medical record, and communicate across providers. 2. Test for the suspected toxins or drugs (e.g., toxicology screens). 3. Observe the child separately from the caregiver, and consider video surveillance where legally and ethically permitted. 4. Involve a multidisciplinary team: pediatrics, social work, child protection team, and psychiatry. 5. Ensure the child's safety first. This may mean separating the child from the caregiver and hospitalizing the child. 6. Report to child protective services. Physicians are mandated reporters, and reasonable suspicion is enough. Proof is not required. 7. Do not confront the perpetrator without a safety plan in place. Treatment of the perpetrator is psychiatric, and prognosis is poor because perpetrators often deny the behavior.

**Board-relevant points** - The correct answer for the perpetrator's diagnosis is FDIA (Munchausen by proxy). The child's diagnosis is child abuse. - Distinguish from related conditions: - Malingering: conscious fabrication for external gain (e.g., money, avoiding work). - Factitious disorder (Munchausen): conscious fabrication for the sick role, with no external gain. - Somatic symptom disorder: unconscious, with real distress about the symptoms. - Conversion disorder (functional neurologic symptom disorder): unconscious neurologic deficits. - Next best step with suspected abuse: ensure the patient's safety and report to child protective services. - Mortality in victims is significant (about 6-10%), and long-term morbidity is also common.