Staphylococcus aureus bacteremias following liver transplantation: a clinical analysis of 20 cases

Therapeutics and Clinical Risk Management Dovepress open access to scientific and medical research O r i g i n a l R e s e a rc h Therapeutics and Clinical Risk Management downloaded from https://www.dovepress.com/ by 54.37.117.73 on 12-Jul-2018 For personal use only. Open Access Full Text Article Staphylococcus aureus bacteremias following liver transplantation: a clinical analysis of 20 cases This article was published in the following Dove Press journal: Therapeutics and Clinical Risk Management 12 June 2015 Number of times this article has been viewed Jiandang Zhou 1,2 Hui Huang 3 Shan Liu 4 Ping Yu 2 Qiquan Wan 5 Department of Clinical Laboratory, the Third Xiangya Hospital of Central South University, 2Department of Immunology, Xiangya School of Medicine, Central South University, 3 Nursing Department, the Third Xiangya Hospital of Central South University, Changsha, Hunan, People’s Republic of China; 4Adelphi University College of Nursing and Public Health, New York, NY, USA; 5Department of Transplant Surgery, the Third Xiangya Hospital of Central South University, Changsha, Hunan, People’s Republic of China 1 Introduction Correspondence: Qiquan Wan Department of Transplant Surgery, the Third Xiangya Hospital of Central South University, No 138 Tongzipo Road, Changsha 410013, Hunan, People’s Republic of China Tel +86 731 8861 8312 Fax +86 731 8861 8312 Email Staphylococcus aureus bacteremia is an important issue complicating the clinical course of liver recipients and has been associated with significant morbidity and mortality, as shown in previous studies with a reported incidence rate of 15%–66% and a mortality rate of 21%.1–3 Our previous study revealed that S. aureus was responsible for 26% of all pathogens causing bacteremias among liver transplant recipients.4 Some researchers have reported a high incidence of methicillin-resistant S. aureus (MRSA) in liver transplant recipients.3,5,6 The increasing antibiotic-resistant S. aureus has emerged as a pivotal factor that influences the prognosis and survival of liver transplant recipients. Herein, we aimed to describe the incidence, clinical and laboratory characteristics, and outcomes of S. aureus bacteremias after liver transplantation and to investigate the drug resistance of S. aureus to frequently used antibiotics to provide evidence for clinical prevention and therapy. 933 submit your manuscript | www.dovepress.com Therapeutics and Clinical Risk Management 2015:11 933–937 Dovepress © 2015 Zhou et al. This work is published by Dove Medical Press Limited, and licensed under Creative Commons Attribution – Non Commercial (unported, v3.0) License. The full terms of the License are available at http://creativecommons.org/licenses/by-nc/3.0/. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. Permissions beyond the scope of the License are administered by Dove Medical Press Limited. Information on how to request permission may be found at: http://www.dovepress.com/permissions.php http://dx.doi.org/10.2147/TCRM.S84579 Powered by TCPDF (www.tcpdf.org) Background: To describe the incidence, clinical characteristics, and outcomes of Staphylococcus aureus bacteremia after liver transplantation and investigate the drug resistance of S. aureus to frequently used antibiotics to provide evidence for clinical prevention and therapy. Materials and methods: In a double-center retrospective study, blood cultures positive for S. aureus were obtained from January 1, 2001 to December 31, 2014. The BACTEC 9120 blood culture system and the Vitek-2 system were used to process blood samples and identify species, respectively. We also collected these patients’ data to confirm clinical and laboratory characteristics. Results: Twenty of 275 (7.3%) liver recipients developed S. aureus bacteremia during the study period. The median time to the onset of S. aureus bacteremias was 6 days after liver transplantation and all episodes of bacteremias were early onset. The lung was the most common source of primary infection, followed by the intra-abdominal/biliary tract. A total of nine (45%) liver recipients died due to S. aureus bacteremias. Of these 20 S. aureus cases, 80% were methicillin-resistant. S. aureus was highly resistant to erythromycin and penicillin (resistance rate .90%). No S. aureus resistant to glycopeptides and oxazolidone antibiotics was observed. There were seven (35%) liver recipients with an inappropriate antibiotic therapy. Between the periods of 2001–2007 and 2008–2014, the distribution of methicillin-resistant S. aureus was not significantly different (P=1.000). Pneumonia as a predominant primary source, a high body temperature, abnormal blood pressure, and decreased platelets, which occurred in the early period after liver transplantation, as well as high morbidity and mortality, were the main characteristics of S. aureus bacteremias. Conclusion: S. aureus led to severe bacteremias in liver recipients, with high morbidity and mortality, and the majority of them comprised methicillin-resistant S. aureus. Keywords: liver transplantation, Staphylococcus aureus, bacteremia, drug resistance Dovepress Zhou et al Therapeutics and Clinical Risk Management downloaded from https://www.dovepress.com/ by 54.37.117.73 on 12-Jul-2018 For personal use only. Materials and methods Study population and clinical isolates This study was conducted both at the Third Xiangya Hospital, an 1,800-bed teaching hospital, affiliated with the Central South University, Changsha, People’s Republic of China, with an active transplantation program (annual average of 30 liver transplants and 150 kidney transplants) and Zhongnan Hospital, a 1,200-bed teaching hospital, affiliated with Wuhan University, Wuhan, People’s Republic of China, with an active transplantation program (annual average of 40 liver transplants and 100 kidney transplants). Liver recipients with an episode of S. aureus bacteremia, between January 1, 2001 and December 31, 2014, were identified from the microbiology laboratory database. Maintenance immunosuppression was based on calcineurin inhibitor (cyclosporine or tacrolimus) and corticosteroids, with or without mycophenolate mofetil. Cyclosporine was administrated to three patients, and tacrolimus was prescribed in the remaining 17 patients. Doses of cyclosporine were adjusted to obtain trough plasma levels of 200–300 ng/mL during the first month and 100–150 ng/mL later on. The initial dose of oral tacrolimus was 0.05 mg/kg twice a day and adjusted to achieve a targeted trough level of 8–10 ng/mL for the first 3 months and 5–6 ng/mL thereafter. Mycophenolate mofetil was prescribed in four patients at a dose of 1 g per day, and the dose was adjusted in response to adverse events. All patients received steroids at a dose of 500 mg/day via intravenous on transplant day 0 then tapered to 5 mg per day, leading to (...truncated)