Prevalence of Subclinical Vitamin K Deficiency in Cholestatic Liver Disease
Current practice is to monitor prothrombin time as an indicator of vitamin K sufficiency in cholestatic liver disease. Since prothrombin time is a surrogate marker, it may underestimate the actual prevalence of vitamin K deficiency in this population. This study investigates the frequency of vitamin K deficiency among a convenience sample of children and adults with cholestatic liver disease by determining plasma levels of protein induced in vitamin K absence II (PIVKA-II), and assesses the relationship between PIVKA-II levels and markers of cholestasis, measured prothrombin time, and vitamin A, E and 25-hydroxyvitamin D levels. Methods: Subjects with cholestatic liver disease were recruited from the Cincinnati referral area. Subjects with decompensated cirrhosis, malignancy, concurrent disease that results in fat malabsorption and AIDS were excluded. All subjects had blood collected for liver function tests, prothrombin time (PT), INR, bile acids, 25-hydroxyvitamin D, vitamin A, vitamin E and PIVKA-II levels. Plasma PIVKA-II concentrations were measured using a commercially available ELISA kit. Results: 31 subjects were enrolled (age range 0.5-54 years). Nine subjects (29%) had prolonged prothrombin times, while 21 (68%) had elevated PIVKA-II levels. All patients with prolonged PT had PIVKA-II elevations. Of the 21 patients with PIVKA-II elevation, 15 were on supplemental vitamin K therapy (range 7.8-700 ?g/kg/day). PIVKA-II levels were positively correlated with serum conjugated bilirubin, bile acids, AST, ALT and measured PT and negatively correlated with serum 25-hydroxyvitamin D levels. Seven subjects (22.5%) had vitamin A deficiency, 5 subjects (16%) had vitamin D deficiency and 2 subjects (8%) had vitamin E deficiency. Conclusions: Despite vitamin K supplementation, vitamin K deficiency, as measured by PIVKA-II, is common in cholestatic liver disease. Better strategies for vitamin K supplementation and dosing guidelines are needed.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:pivka ii vitamin k liver disease
Date of Publication:01/01/2004