801 - From Virus to Ventilator: Hepatitis C in Acute Flaccid Myelitis

A 13-year-old female with no past medical history presented with progressive headaches and acute upper back pain preceded by an URI, quickly progressing to acute flaccid myelitis (AFM) with unclear etiology.

Imaging showed widespread T2 hyperintensities to the cervical and thoracic cord, medulla and conus, reactive paraspinal edema and acute medullary infarct. Autoimmune and rheumatologic panels were unremarkable except for a weak, inconsistent GAD65. Infectious workup was largely negative except persistently positive Hepatitis C virus (HCV) RNA, likely perinatally acquired from a mother with chronic HCV.

Case Description:

Inpatient treatment included IVIG, high-dose methylprednisolone, plasmapheresis, rituximab, and sofosbuvir-velpatasvir, alongside supportive care including neurogenic bladder catheterization, bowel regimen, wound care, anticoagulation for venous thromboses, and psychiatric support.

Through intensive multidisciplinary rehabilitation, she regained limited upper extremity movement, improved speech and swallowing, cuff deflation with brief ventilator weans, and ability to use powered wheelchair mobility. Though cognition, communication and emotional adjustment have some improvements, she requires additional rehabilitation and possibly further treatments to regain function.

Discussions:

This case highlights unusual etiologies in AFM and the importance of a broad differential. Although rare, concurrent HCV infection may act as a trigger; only few pediatric cases reported this connection. Medullary involvement explained her profound ventilator dependence, while unremarkable autoimmune and infectious panels reinforce the value of comprehensive evaluation. AFM treatment remains empiric; immunotherapies are standard, while antivirals are typically reserved for HCV. Their combined use was uncommon in AFM but appeared to support recovery and may inform future cases. The recovery trajectory highlights the role of inpatient rehabilitation in improving quality of life and functional outcomes even in severe cases.

Conclusions:

This atypical case suggests AFM likely caused by HCV. It underscores the role of aggressive interdisciplinary rehabilitation and the need for continued research into AFM causes and treatment.