Diagnostic odyssey of acute disseminated encephalomyelitis in children

We aimed to determine whether acute disseminated encephalomyelitis (ADEM) diagnosis in children is delayed, and if so, to identify the clinical risk factors of delayed diagnosis. Standardised data were collected from children with ADEM from 2003 to 2020. Overall diagnostic delay (time between symptom onset and ADEM diagnosis), physicians’ delay (between the first medical visit and ADEM diagnosis), and patients’ delay (between symptom onset and the first medical visit) were analysed. Thirty ADEM patients were identified, including 16 (54%) with neurological deficits at discharge. Overall, physicians’, and patients’ delays were 9 (interquartile range [IQR] 6–20.5), 5.5 (IQR 3–14), and 4 (IQR 2–8) days, respectively. Overall delay was significantly associated with physicians’ delay, but not with patients’ delay. There were 61 misdiagnoses among 25 (83%) patients, while 5 (17%) were diagnosed correctly at the first visit. The misdiagnoses of common respiratory and gastrointestinal infection and aseptic meningitis were associated with overall and/or physicians’ delay. Later onset of specific neurological features suggestive of ADEM was associated with all three diagnostic delays. A unique diagnostic odyssey exists in ADEM. Several clinical risk factors were associated with the diagnostic delay.