# Case Report: Neurolymphomatosis of the peripheral nerve as a presentation of relapsed pediatric high-grade B cell lymphoma

## TL;DR

A rare case of neurolymphomatosis in a child with relapsed lymphoma is reported, highlighting the importance of early diagnosis and the potential role of ultrasound.

## Contribution

This is the first reported case of neurolymphomatosis in a pediatric patient and highlights the use of ultrasonography in diagnosis.

## Key findings

- Neurolymphomatosis presented as peripheral nerve involvement in a child with relapsed high-grade B cell lymphoma.
- Ultrasonography aided in diagnosing NL with palpable mass and neurological signs.
- Early identification and treatment of NL are critical for improved outcomes.

## Abstract

Neurolymphomatosis (NL) of the peripheral nerve in pediatrics has never been reported, and ultrasonography (USG) as an investigation modality is rarely used. We report a case of an 11-year-old boy with stage 4 mature high-grade B cell lymphoma who presented with a two-week history of right ulnar neuropathy and left sciatic neuropathy one month after the completion of frontline chemotherapy. This case report illustrates the rare presentation of NL in lymphoma relapse and hopes to emphasize how early identification of this diagnosis and timely treatment are essential. Moreover, this case points out how USG, in the context of palpable mass and localized neurological signs, could facilitate a diagnosis of NL.