Idiosyncratic reactions are the most common cause of abnormal liver function tests in patients with cystic fibrosis

Background: Beta-lactam antibiotic-related liver enzyme derangement can limit treatment options for infective exacerbations in cystic fibrosis (CF) bronchiectasis. Aim: To identify risk factors for elevated liver function tests (LFT) in CF patients receiving parenteral antibiotics. Methods: All patients attending The Prince Charles Hospital (TPCH) Adult CF Centre in 2012 were identified using the CF Research Database and CF Data Registry. Biochemistry and haematology panels between 1 January 2012 and 31 December 2012 for each patient were retrieved from Queensland Health Pathology and private pathology providers. Patients with LFT more than three times the upper limit of normal were identified. For each laboratory test, concurrently administered antibiotic(s) were analysed from TPCH pharmacy dispensing system for patients who received intravenous (IV) antibiotic treatment. Results: Abnormal liver enzymes were evident in significantly more patients receiving IV antibiotics than patients who did not (43% vs 18%, P < 0.001). Pre-existing CF-related liver disease and total IV antibiotic treatment days were not associated with abnormal LFT. Higher C-reactive protein and peripheral eosinophil counts were not more common in patients with abnormal LFT. Male sex, poorer lung function and lower leucocyte counts were associated with abnormal LFT; however, these variables only explained 4.2% of the variance in the multivariable logistic model. Conclusion: Elevated LFT are common during IV antibiotic treatment in CF. Although specific antibiotic exposure may contribute to abnormal LFT in a minority of cases, our study demonstrates that antibiotic-induced liver injury is largely idiosyncratic and unpredictable