# Successful alemtuzumab retreatment in multiple sclerosis following previous diffuse alveolar haemorrhage

## TL;DR

A patient with multiple sclerosis successfully received alemtuzumab retreatment after a rare lung complication, showing it can be safe with proper monitoring.

## Contribution

This case report demonstrates the feasibility of alemtuzumab retreatment after DAH with close monitoring.

## Key findings

- Alemtuzumab retreatment was successful without recurrence of diffuse alveolar haemorrhage.
- Regular monitoring and early investigations are crucial for safe retreatment.

## Abstract

Alemtuzumab-induced diffuse alveolar haemorrhage (DAH) is a rare but serious complication in people with relapsing-remitting multiple sclerosis (RRMS). Evidence supporting retreatment despite adverse events remains limited. We report a 29-year-old female who developed DAH during the first alemtuzumab cycle and was subsequently retreated 1 year later following interdisciplinary advice from respiratory. There was no recurrence of DAH. This case report provides evidence towards retreatment feasibility with regular monitoring and low thresholds for laboratory and radiological investigations.