A 20-year-old man with a history of B-cell acute lymphoblastic leukemia (ALL) in remission reported a 2-week history of bilateral lower limb weakness. Electrophysiologic examination showed prolonged latency of F-wave of bilateral tibial nerves. The CSF opening pressure was increased (>30 cm/H20), with elevated protein level (1683 mg/L, RI 150–400 mg/L), decreased glucose concentration (5.94 mg/dL, RI 50.4–80.64 mg/dL), and pleocytosis (854/mm3, RI < 10/mm3) in CSF. Flow cytometry assays for detecting minimal residual disease in CSF disclosed numerous lymphoblasts (CD45+, CD19+, CD34+, CD10+, CD38±, and CD20−), and lumbosacral MRI showed thickened and homogeneously enhanced cauda equina, which were consistent with nervous system relapse of B-cell ALL (Figure).1 Cauda equina involvement as a manifestation of ALL relapse is rare, and lumbosacral MRI markedly improved diagnosis.
This work was supported by the Innovation Research Team Project of Natural Science Foundation of Hainan (2018CXTD348).
The authors report no disclosures relevant to the manuscript. Go to Neurology.org/N for full disclosures.
- Received November 29, 2021.
- Accepted in final form February 25, 2022.
- © 2022 American Academy of Neurology