# Colovesical Fistula and Amyloidosis

## TL;DR

A 71-year-old man with amyloidosis developed a rare connection between his colon and bladder due to protein buildup.

## Contribution

This case highlights a rare gastrointestinal complication of systemic amyloidosis.

## Key findings

- Amyloid deposition can lead to a colovesical fistula in patients with systemic amyloidosis.
- Gastrointestinal symptoms like bleeding and diarrhea are common in amyloidosis due to mucosal or vascular infiltration.
- The case emphasizes the need for careful monitoring of gastrointestinal complications in amyloidosis patients.

## Abstract

Systemic amyloidosis results from an abnormal deposition of toxic insoluble beta-sheet fibrillar protein in extracellular tissues, causing damage to multiple organ systems. Amyloid proteins (e.g., transthyretin, light chains, and serum amyloid A) may infiltrate the mucosa or vascular structures, resulting in gastrointestinal manifestations, including bleeding and diarrhoea. We discuss a case of a 71-year-old male with systemic immunoglobulin G kappa amyloid light chain amyloidosis who developed a colovesical fistula related to amyloid deposition.