Zipper cell endotheliopathy: a new subset of idiopathic corneal edema.
OBJECTIVE
To report the clinical and histologic findings of a new subset of idiopathic corneal edema: zipper cell endotheliopathy.


METHODS
Observational case report.


METHODS
A 55-year-old woman with unilateral bullous keratopathy.


METHODS
Clinical observation consisted of slit-lamp examination and in vivo confocal microscopy (IVCM). Aqueous humor samples and the excised corneal button were analyzed for the presence of herpes viruses. The excised cornea was subjected to detailed immunohistochemistry (IHC) and scanning and transmission electron microscopy.


METHODS
Clinical and pathologic characteristics of zipper cell endotheliopathy.


RESULTS
In vivo confocal microscopy revealed unique morphologic alterations of the corneal endothelial layer. Focal areas of denudation were surrounded by endothelial cells with zipper-like cell borders and intercellular structures. Besides central corneal edema, no other signs of corneal inflammation were detected. A herpes virus origin for the bullous keratopathy was excluded. The IHC analysis disclosed positive staining for cytokeratin (CK) 7, CK8/18, and CK19, suggesting epithelial metaplasia of the endothelial cells. Ultrastructural examination confirmed the IVCM findings by showing large areas of endothelial denudation and vacuolated endothelial cells with large, broad-based extensions that partially overlapped neighboring cells. Despite extensive complementary research and review of the literature, the endothelial alterations could not be attributed to any known corneal disorder.


CONCLUSIONS
To the authors' knowledge, zipper cell endotheliopathy is a new subset of idiopathic corneal edema. The case report presented illustrates the potential use of IVCM to differentiate the spectrum of corneal disorders and to discover new corneal diseases.
Hillenaar
Toine
T
Rotterdam Ophthalmic Institute, Rotterdam, The Netherlands. t.hillenaar@oogziekenhuis.nl
Mooy
Cornelia M
CM
Verjans
Georges M G M
GM
Remeijer
Lies
L
D015415:Biomarkers / Q000378:metabolism; D015715:Corneal Edema / Q000175:diagnosis* / Q000378:metabolism; D004728:Endothelium, Corneal / Q000378:metabolism / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000378:metabolism; D008679:Metaplasia; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D014792:Visual Acuity
D015415:Biomarkers; D007633:Keratins