Costaining for keratins 8/18 plus ubiquitin improves detection of hepatocyte injury in nonalcoholic fatty liver disease.
Nonalcoholic fatty liver disease is a global health dilemma. The gold standard for diagnosis is liver biopsy. Ballooned hepatocytes are histologic manifestations of hepatocellular injury and are characteristic of steatohepatitis, the more severe form of nonalcoholic fatty liver disease. Definitive histologic identification of ballooned hepatocytes on routine stains, however, can be difficult. Immunohistochemical evidence for loss of the normal hepatocytic keratin 8/18 can serve as an objective marker of ballooned hepatocytes. We sought to explore the utility of a keratin 8/18 plus ubiquitin double immunohistochemical stain for the histologic evaluation of adult nonalcoholic fatty liver disease. Double immunohistochemical staining for keratin 8/18 and ubiquitin was analyzed using 40 adult human nonalcoholic fatty liver disease core liver biopsies. Ballooned hepatocytes lack keratin 8/18 staining as previously shown by others, but normal-size hepatocytes with keratin loss are approximately 5 times greater in number than keratin-negative ballooned hepatocytes. Keratin-negative ballooned hepatocytes, normal-size hepatocytes with keratin loss, and ubiquitin deposits show a zonal distribution, are positively associated with each other, and are frequently found adjacent to or intermixed with fibrous matrix. All 3 lesions correlate with fibrosis stage and the hematoxylin and eosin diagnosis of steatohepatitis (all P < .05). Compared with hematoxylin and eosin staining, immunohistochemical staining improves the receiver operating characteristics curve for advanced fibrosis (0.77 versus 0.83, 0.89, and 0.89 for keratin-negative ballooned hepatocytes, normal-size hepatocytes with keratin loss, and ubiquitin, respectively) because immunohistochemistry is more sensitive and specific for fibrogenic hepatocellular injury than hematoxylin and eosin staining. Keratin 8/18 plus ubiquitin double immunohistochemical stain improves detection of hepatocyte injury in nonalcoholic fatty liver disease. Thus, it may help differentiate nonalcoholic steatohepatitis from nonalcoholic fatty liver.
Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA.
Cynthia D
CD
Guy
Ayako
A
Suzuki
James L
JL
Burchette
Elizabeth M
EM
Brunt
Manal F
MF
Abdelmalek
Diana
D
Cardona
Shannon J
SJ
McCall
Aynur
A
Ünalp
Patricia
P
Belt
Linda D
LD
Ferrell
Anna Mae
AM
Diehl
D015415:Biomarkers / Q000032:analysis*; D005234:Fatty Liver / Q000175:diagnosis* / Q000378:metabolism; D005260:Female; D022781:Hepatocytes / Q000737:chemistry / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D053538:Keratin-18 / Q000032:analysis*; D053533:Keratin-8 / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease; D025801:Ubiquitin / Q000032:analysis*
D015415:Biomarkers; C488421:KRT18 protein, human; D053538:Keratin-18; D053533:Keratin-8; D025801:Ubiquitin