Tartrate-resistant acid phosphatase isoform 5a as an inflammation marker in end-stage renal disease.
OBJECTIVE
End-stage renal disease (ESRD) is often complicated by chronic inflammation and malnutrition. We tested whether serum tartrate-resistant acid phosphatase (TRACP) isoform 5a relates to other markers of inflammation in ESRD.


METHODS
Predialysis serum was collected from 99 ESRD patients (51 male, 48 female) aged 55 +/- 15 years and a control group of 36 healthy subjects (8 male, 28 female) aged 43.2 +/- 10.5 years.


METHODS
Serum TRACP 5a activity and protein, TRACP 5b activity and C-reactive protein (CRP) were estimated by in-house immunoassays. Commercial kits were used for serum bone-specific alkaline phosphatase, Ntelopeptides of Type I collagen, interleukin-6 (IL-6) and fetuin-A. Intact parathyroid hormone was determined by chemiluminescent assay. Albumin, cholesterol, triglycerides, ferritin and hemoglobin were compared to the hospital reference ranges. Bone mineral density (BMD) was measured at the heel in 69 patients and all control subjects and expressed as g/cm2 and age-corrected T-score.


RESULTS
Mean (median) levels of all serum markers were significantly elevated in ESRD except fetuin-A, which was significantly reduced. Mean BMD (g/cm2) was not different than control, but mean T-score was significantly reduced. TRACP 5a protein correlated with CRP, triglycerides and ferritin, but not with IL-6 or any other nutritional or bone markers or BMD. TRACP 5b activity correlated with all bone markers and BMD, but not with inflammation or nutritional markers.


CONCLUSIONS
Our findings suggest that TRACP 5a may be a useful marker to estimate the degree of inflammation in ESRD patients on chronic hemodialysis.
Special Hematology Laboratory, Veterans Affairs Medical Center, Louisville, KY 40206, USA. anthony.janckila@va.gov
A J
AJ
Janckila
E D
ED
Lederer
B A
BA
Price
L T
LT
Yam
D000135:Acid Phosphatase / Q000097:blood*; D000328:Adult; D000418:Albumins / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D024042:Collagen Type I / Q000097:blood; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D007527:Isoenzymes / Q000097:blood*; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D020033:Protein Isoforms / Q000097:blood; D006435:Renal Dialysis; D018709:Statistics, Nonparametric; D000071681:Tartrate-Resistant Acid Phosphatase; D000509:alpha-Fetoproteins / Q000378:metabolism
D000418:Albumins; D015415:Biomarkers; D024042:Collagen Type I; D015850:Interleukin-6; D007527:Isoenzymes; D010281:Parathyroid Hormone; D020033:Protein Isoforms; D000509:alpha-Fetoproteins; D002097:C-Reactive Protein; D000469:Alkaline Phosphatase; C000605510:ACP5 protein, human; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase