Frayed Abomination Stitching

Frayed Abomination Stitchings are magically enhanced thread used to hold together Abominations. They are used as an ingredient in numerous quests for rare and valuable magic items.

Source
This item drops from:
 * Bile Spewer in Stratholme
 * Ramstein the Gorger in Stratholme
 * Venom Belcher in Stratholme
 * Patchwork Horror in Stratholme

Frayed Abomination Stitching as a quest objective
This item is an objective for the following quests:

Burning Crusade and Beyond
Unless you are a completionist, there is virtually no use for this item anymore. As of Patch 3.08 they still drop from the above mentioned monsters within Stratholme, usually between 3-6 per run. However, they cannot be sold to a vendor.