Evaluation of serum bone alkaline phosphatase activity in patients with liver disease: Comparison between electrophoresis and chemiluminescent enzyme immunoassay.
BACKGROUND
Serum bone alkaline phosphatase (ALP) is a marker of bone formation and metabolism. However, existing methods for measuring it have their limitations and their accuracy has not been determined.


METHODS
We measured serum bone ALP activity in 127 patients with liver disease using 2 methods: electrophoresis and chemiluminescent enzyme immunoassay (CLEIA). The results of these 2 methods were compared and analyzed according to gender, age and several serum biochemical markers.


RESULTS
When ALP3 (%; bone-type isozyme activity as a percentage of total ALP activity) values were high, the 2 methods showed good correlation. However, with a decrease in ALP3 (%) levels, the correlation coefficient (R) also decreased. Starting with ALP3 (%)<23, R values markedly decreased to <0.50 (p>0.05). Five outliers displayed low ALP3 (%) activity levels. Furthermore, in regard to genders, there were significant differences in total cholesterol (TC), γ-glutamyltransferase (γ-GTP), ALP and ALP3 (%) levels (p<0.05).


CONCLUSIONS
When serum ALP3 (%) levels were high in patients with liver disease, the accuracy of electrophoresis was comparable to that of CLEIA. However, the accuracy of electrophoresis needs to be evaluated with further when patient samples under certain conditions.
Department of Laboratory Medicine, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan.
Fangjie
F
Zhan
Department of Laboratory Medicine, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan.
Yoshihisa
Y
Watanabe
Department of Clinical Laboratory, Hamamatsu University Hospital, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan.
Aya
A
Shimoda
Department of Clinical Laboratory, Hamamatsu University Hospital, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan.
Etsuko
E
Hamada
Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan.
Yoshimasa
Y
Kobayashi
Department of Laboratory Medicine, Hamamatsu University School of Medicine, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan; Department of Clinical Laboratory, Hamamatsu University Hospital, 1-20-1, Handayama, Higashi-ku, Hamamatsu 431-3192, Japan. Electronic address: mmaekawa@hama-med.ac.jp.
Masato
M
Maekawa
D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood*; D001842:Bone and Bones; D004796:Clinical Enzyme Tests / Q000592:standards*; D004586:Electrophoresis; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007527:Isoenzymes / Q000097:blood; D008107:Liver Diseases / Q000201:enzymology*; D008297:Male; D008875:Middle Aged
D007527:Isoenzymes; D000469:Alkaline Phosphatase
Alkaline phosphatase isozyme; Bone-type alkaline phosphatase; Chemiluminescent enzyme immunoassay; Electrophoresis; Liver disease