Lıver autoantıbodıes ın patients with osteoporosis Demirdal US et al. One of the main characteristics of the disease is the presence of circulating autoantibodies. It has been sug- gested that liver membrane antibodies (LMA) and liver specific protein (LSP) are associated with ALD.15,16 Defined antibodies are antinuclear antibodies (ANA), anti-smooth muscle antibodies (SMA), and anti-liver/kidney microso- mal autoantibodies1 (anti-LKM1) in addition to perinuclear antineutrophil cytoplasmic antibodies (pANCA), antibodies to liver-cytosol type 1 (anti-LC-1), autoantibodies to soluble liver antigen/liver pancreas antigen (anti-SLA/LP), anti- bodies to the asialoglycoprotein receptor (anti-ASGPR), and anti-mitochondrial antibodies (AMA).14,17 The prevalence of OP is higher in patients with PBC, and osteoporotic fractures are more prevalent in patients with AH treated with glucocorticoids.18 However, it is not clear whether or not chronic liver diseases – especially ALD – are related to the secondary OP. There are a few studies investigating liver diseases as a secondary cause of OP.8,19 Therefore, we aimed to assess the circulating autoantibodies related to ALD in patients with OP. MATERIALS AND METHODS The study was conducted at Afyon Kocatepe University Hospital following the approval of the Ethical Committee for Medical Research of the university. Postmenopausal women age 50 or older with OP were included in the study. Two hundred and eighty-seven postmenopausal women were evaluated. Bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA, HOLOGIC Q DR 4500 W) both at the lumbar spine (anteroposterior projection of L1–L4), and the proximal femur (total score) if the patients were 50 years or older. Osteoporosis is defined as T score below -2.5 at any site according to WHO guidelines.1 Smoking, alcohol use, medication (especially drugs with high risk of liver toxicity), malignancy, history of gastrointestinal system (thyroid gland, kidney, and liver diseases), rheumatologic conditions, and nutrition were questioned in detail. Patients with secondary risk factors and anatomic deformity in lumbar and femoral region that affects BMD were excluded. In total, 287 postmenopausal women were evaluated; of these, 150 presented the criteria for participation in this study. Venous blood samples were drawn in the morning after an overnight fast. Serum levels of aminotransferases (aspartate aminotransferase-AST, alanine aminotransferase-ALT), cal- cium (Ca), phosphate (PO4), alkaline phosphatase (ALP), parathyroid hormone (PTH), 25-(OH) vitamin D, osteocalcin (OC), and serum C-telopeptide cross-linked collagen type I (CTX) were measured on the same day. Serum PTH was measured by immunoradiometric assay (IRMA, USA). Serum CTX was measured by electrochemiluminescence immunoassay (ECLIA, Germany). Serum osteocalcin was measured with an RIA (radioimmunoassay) technique (DiaSorin, Saluggia, Italy). The level of 25-(OH) vitamin D was measured by radioimmunoassay (RIA) (Nichols Institute Diagnostics, USA). The levels of Ca, PO4, and ALP were measured by colorimetric method. Serum was assayed using an autoanalyzer to measure the levels of aminotransferases. All blood tests were performed in a single laboratory using reference ranges of this laboratory’s data. Serum samples were analyzed for autoantibodies by indirect immunofluorescence (IIF) on a substrate kit (Euroimmun, Germany) that included fluorescein-conju- CLINICS 2010;65(10):971-974 gated goat antibodies to human immunoglobulin G (IgG). IIF patterns were read at serum dilutions of 1:100 for ANA, SMA, AMA, and anti-LKM1 positivity on a Zeiss Axioskop (Carl Zeiss, Jena, Germany) by the same experienced microbiologist. LMA and LSP were tested by the same method with minimal titers for positivity being 1:80. The levels of aminotransferases were re-examined when auto- antibody positivity was determined. The analyses were carried out using SPSS version 13.5. Descriptive analysis was carried out and data were expressed as percentages (%), means, and standard devia- tions. RESULTS Two hundred and eighty-seven postmenopausal women were evaluated and, of these, 150 patients were found to be eligible to include in this study. The mean age of the patients was 63,13¡8,6 years. The mean values of L1-L4 T-scores and femur total T-scores, were -3,08¡0,58 and -1,53¡0,81, respectively. Upon evaluation of the question- naires, none of the patients had signs or symptoms of liver diseases. The mean values of the enzymes reflecting liver functions and markers of bone metabolism are shown in Table 1. The mean values for all the laboratory tests were within the normal range. Among the 150 patients with OP, 14 (9.3%) were ANA, four (2.7%) were LMA for 1:80 titers, three (2.0%) were anti- LKM1, and two (1.3%) were LSP positive. None of the patients had AMA or SMA positivity. Serological para- meters are summarized in Table 2. Only one patient was found to have positivity for two and more autoantibodies (LMA and anti-LKM1). In laboratory examination of the patient, all biochemical tests were within the normal range. Table 1 - Values of serum aminotransferases and bone metabolism markers. Serum Type Serum AST (U/l) Serum ALT (U/l) Serum ALP (U/l) Serum Ca (mg/dl) Serum PO4(mg/dl) Serum PTH (pg/ml) 25-OH-vitamin D (ng/ml) Serum Osteocalcin (ng/ml) Serum CTX (ng/ml) Mean Values 22.37¡17.08 20.10¡10.34 227.87¡69.96 9.87¡0.53 3.54¡0.54 49.84¡45.07 28.96¡36.58 11.77¡13.28 0.55¡0.38 Min-Max Values 2.55-66 5.0-190.0 42.9-387.2 8.45-11.48 2.1-4.75 4.0-96.0 12.3-74 1.01-64.01 0.33-1.96 Normal Values 0-32 0-41 98-278 8.2-10.2 2.7-4.5 10-70 10-50 6.8-34 0.33-0.78 Table 2 - Liver autoantibodies positivity (%) in patients with osteoporosis 972 Autoantibodies ANA LMA Anti-LKM1 LSP SMA AMA n (150) 14 4 3 2 0 0 Positivity % 9.3 2.7 2.0 1.3 0 0