Thrombus on indwelling central venous catheters: The histopathology of 'fibrin sheaths'

Purpose: Central venous catheters (CVC) may fail for many reasons, though 'fibrin sheaths' blocking catheter ports are usually implicated. We examined the sheaths removed from dialysis catheters to determine their histopathology.Methods: Ten catheter strippings were performed and the removed material was studied grossly and microscopically.Results: The histologic specimens showed thrombus both with and without a proteinaceous sheath.Conclusion: Dialysis catheters fail because of thrombus formation. This can occur in either the absence or presence of a protein coating on the catheter, the so-called 'fibrin sheath.'