Table 6.
Comparison between ME/CFS and factitious disorder/Munchausen’s syndrome by proxy/fabricated or induced illness.
| Pediatric ME/CFS | Factitious disorder by proxya | |
|---|---|---|
| Prevalence | Approximately 100–500 per 100,000 | Very rare, approximately 0.4–2 per 100,000 |
| Age and age range | Peak age 10–17 years, range 2–17 years | Average age 4 years; >50% of patients are aged <2 years; extremely rare in adolescents |
| Symptoms | Consistent pattern of symptoms: reduction in activity, post-exertional worsening of symptoms, fatigue and loss of stamina, unrefreshing sleep, cognitive problems, orthostatic intolerance and headaches; a history of surgeries is uncommon | No consistent symptoms. Most frequently reported are: apnea/cyanosis, anorexia/feeding problems, diarrhea, seizures, asthma, allergy, fevers, behavioral problems, and other sometimes bizarre symptoms, a history of surgeries is common |
| Clinical signs | Intermittent conspicuous facial pallor, acrocyanosis, joint hypermobility common, blood pressure can fall or heart rate rise on prolonged standing | No consistent clinical signs, many patients have multiple surgical scars |
| Orthostatic intolerance (OI) | Many patients have POTS or NMH | Not reported |
| Blood testing | Routine blood tests usually normal | Routine blood tests can show bizarre abnormalities |
| Neuroimaging | Neuroimaging can reveal defects in brain perfusion and/or metabolism | No reports of neuroimaging |
| Multiple doctors seen | Common | Common |
| Hospital admissions | Hospital admissions unusual | Hospital admissions very common |
| Medical knowledge | Parents can be very knowledgeable about ME/CFS | Parent/perpetrator can be knowledgeable about medical conditions |
| School absence | Common, it is the most common medical cause of prolonged school absence | Most patients are pre-school age. Common in school-age patients |
| Separation from parents | Detrimental. Patient does not recover, illness often worsens | Patient improves/recovers when separated from a parent/perpetrator |
| Mortality | Extremely low | Approximately 10% in patients and 25% in patients’ siblings |
aShaw et al. (89).