Prevalence, aetiology and associated co-morbidities of elevated aminotransferases in a german cohort of orthopaedic surgery patients.

INTRODUCTION: In a recent study on hepatitis C prevalence, we identified a high prevalence of elevated liver enzymes, well above 10 %, in orthopaedic surgery patients without evidence for viral hepatitis. We now report in another cohort, that the prevalence is indeed in that range, and that in these patients elevated liver enzymes are likely indicators for existing comorbidities.

METHODS: 1064 patients referred to the Department of Orthopaedic Surgery, University of Leipzig, between January 2001 and July 2005 were screened routinely for serological markers against hepatitis B and C. Out of these patients 960 individuals were tested additionally for liver enzymes. Patients with elevated aminotransferases but no evidence for hepatitis B or C were compared with two age- and sex-matched controls with normal liver enzymes to evaluate differences in the frequency of comorbidities.

RESULTS: The prevalence of hepatitis B and C was low (HBs-antigen positive: 0.41 %, anti-HCV positive: 0 %). Of the 960 patients with no evidence for viral hepatitis and available aminotransferase values 108 cases (11.3 %) showed elevated ALT, 67 individuals (7 %) elevated AST and 125 patients (13 %) showed elevation of either one or both aminotransferases. Patients with elevated liver enzymes had a significantly higher prevalence of hypertension (73.6 vs. 57.2 %; p = 0.002), chronic ischaemic heart disease (CIHD) (30.4 vs. 15.6 %; p = 0.001), hyperlipidaemia (30.4 vs. 14.8 %; p = 0.001) and hyperuricaemia (36 vs. 23.6 %; p = 0.014). Type 2 Diabetes mellitus tended to be more frequent in patients with elevated liver enzymes, too (p = 0.056). Individuals with elevated aminotransferases presented a mean BMI of 28.7 kg/m (2) in comparison to 27.5 kg/m (2) in the control group (p = 0.055). By excluding patients with regular daily alcohol consumption, the prevalence of abnormal liver enzymes was still remarkably high (9 %).

CONCLUSION: Our study proved a high prevalence of elevated aminotransferases in orthopaedic surgery patients, most frequently caused by NAFLD, and its association with a high rate of concomitant diseases. Thus, abnormal liver enzymes should lead to a focused screening for concomitant diseases such as diabetes, hypertension and coronary atherosclerosis.