[Guillain-Barré syndrome following allogeneic hematopoietic stem cell transplantation in a pediatric patient: a case report and literature review].

A 10-year-old girl diagnosed with hyper-IgE syndrome for more than six years developed dizziness and symmetrical progressive limb weakness one week prior to hospital admission, occurring 4 months after allogeneic hematopoietic stem cell transplantation. On post-transplant day 121, dizziness and progressive, symmetric limb weakness appeared. Cerebrospinal fluid analysis revealed albuminocytologic dissociation. Electromyography confirmed multiple peripheral nerve lesions, consistent with the diagnosis of Guillain-Barré syndrome. Intravenous immunoglobulin therapy showed limited efficacy, whereas corticosteroid therapy produced significant clinical improvement. Neurological symptoms fully resolved after treatment; however, severe chronic graft-versus-host disease occurred subsequently. Based on this case, related literature was reviewed and summarized to provide references for early diagnosis, mechanistic investigation, and treatment options.