# Factor X Concentrate Treatment Schedule and Dosing in Acquired FX Deficiency

## TL;DR

This case report describes the successful use of FX concentrate to manage bleeding in a patient with acquired FX deficiency caused by AL amyloidosis.

## Contribution

The paper provides a novel treatment strategy for managing acquired FX deficiency using FX concentrate dosing to achieve specific FX levels.

## Key findings

- Maintaining FX trough levels above 20% successfully stopped bleeding symptoms.
- FX levels above 50% enabled safe performance of urgent invasive procedures.

## Abstract

Background: Acquired factor X (FX) deficiency is a rare condition that can cause life threatening bleeding. Here we outline a successful management strategy for gastrointestinal bleeding (GI) using human FX concentrate. Case description: A 61-year-old male presented with upper GI bleeding and a prolonged prothrombin time. Investigations demonstrated an acquired FX deficiency (determined to be secondary to AL amyloidosis). Results: Treatment with FX concentrate to maintain trough FX levels >20% resulted in successful cessation of bleeding symptoms, and levels >50% facilitated urgent invasive procedures. Conclusions: This case report adds valuable insight into the management of this rare condition, and how best to utilize FX concentrates in acquired FX deficiency.