Detection of early squamous metaplasia in bladder biopsies of spinal cord injury patients by immunostaining for cytokeratin 14.

Study Design: A prospective, immunohistochemical study of bladder biopsies taken from spinal cord injury (SCI) patients.

Objectives: To investigate whether cytokeratin 14 immunostaining may be useful to detect early squamous metaplasia in bladder biopsies from patients with SCI.

Setting: Southport, United Kingdom.

A study of cytokeratin 20 immunostaining in the urothelium of neuropathic bladder of patients with spinal cord injury.

Background: Normal urothelium is characterised by terminally differentiated superficial cells, which express cytokeratin 20 in the cytoplasm. In contrast, cultured human stratified urothelium, which does not undergo complete terminal differentiation of its superficial cells, does not express cytokeratin 20. If spinal cord injury (SCI) affects urothelial differentiation or induces squamous or other metaplastic change undetected by histological analysis, the superficial urothelial cells of the neuropathic bladder might be expected to show absence of immunostaining for cytokeratin 20.

Loss of cytokeratin 14 expression is related to human papillomavirus type and lesion grade in squamous intraepithelial lesions of the cervix.

In a recent study of low-grade cervical squamous intraepithelial lesions (SILs), we reported that infection with both low- and high-risk human papillomaviruses (HPVs) upregulated cyclin A, B, E, and Ki67 expression in basal and suprabasal cells. In view of the intricate link between cell cycle exit, proliferation, and differentiation, we examined the morphologic distribution of cytokeratins 13 and 14 and involucrin expression in 49 low-grade SILs infected with HPV types 6, 11, 16, 18, 31, 33, 39, 42, 43, 44, 45, 51, 52, 56, 58, and 66; 2 lesions contained both low- and high-risk HPVs. The findings were compared with 30 high-grade SILs infected with HPV types 16, 31, 33, 51, 58, 66, and 67; 3 of these were infected with 2 different HPVs.