Urinary Bladder - Proteinaceous Plug
comment:Proteinaceous plugs are commonly noted as a postmortem change resulting from an agonal secretion of accessory sex gland fluids during euthanasia. Proteinaceous plugs vary in size but can be large, filling the urinary bladder ( Figure 1 and Figure 2 ). Microscopically, the plug is composed of a mixture of an amorphous eosinophilic material, sometimes containing desquamated epithelial cells and spermatozoa. Proteinaceous plugs by themselves have no toxicologic importance and are not precursors of calculi. Plugs may be seen with obstructive syndromes associated with bacterial inflammation. They must be differentiated from calculi.
recommendation:Proteinaceous plugs occurring alone and not associated with any pathologic lesions should be recognized as an artifact and should not be diagnosed. Occasionally, proteinaceous plugs are recognized grossly, and the pathologist should use his or her judgment to correlate the gross lesion to an artifactual proteinaceous plug.
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