The Path to Finding a Unifying Diagnosis – A Case Report of Mitchell Syndrome in a Pediatric Patient
Vanessa Nguyen1, Duo Li2, Saila Upadhyayula1
1Pediatric Neurology, Emory University, 2Pediatrics, Children's Healthcare of Atlanta
Objective:
We present a case report of a pediatric patient who developed corneal ulcerations, sudden bilateral sensorineural hearing loss, diffuse keratosis pilaris, and gait abnormality within 4 months, who ultimately was diagnosed with an ACOX1 mutation, significant for Mitchell Syndrome.
Background:
Mitchell syndrome is an extremely rare, progressive disorder that is characterized by episodic demyelination, sensorimotor polyneuropathy changes, and hearing loss. It is caused by a de novo heterozygous missense mutation in acyl-CoA oxidase (ACOX1), which causes an increase in reactive oxygen species level. As of June 2022, less than twenty people in the world have been diagnosed with this syndrome.
Design/Methods:
Our patient is a twelve-year-old male who was admitted for evaluation of acutely progressive lower extremity weakness. CSF studies were notable only for elevated protein. MRI Brain was normal, but MRI complete spine revealed a long segment dorsal cord enhancing signal abnormality spanning the entire cord length, with enhancement of cauda equina nerve roots. EMG results were consistent with severe length dependent sensory motor polyneuropathy of predominantly axonal type.
Results:

The patient received 2 rounds of high dose steroids and 2 doses of IVIG 1g/kg. Following the confirmation of his underlying diagnosis, he was started on N-acetyl cysteine supplementation for compassionate use to help mitigate disease symptoms.

Conclusions:

The constellation of episodic demyelination, sensorimotor polyneuropathy, and sensorineural hearing loss should raise suspicion for an underlying genetic syndrome, specifically Mitchell Syndrome.

10.1212/WNL.0000000000205523