Clinical study of an outbreak of postoperative mediastinitis caused by Serratia marcescens in adult cardiac surgery

Abstract

OBJECTIVES Nosocomial infection caused by Serratia marcescens after cardiac surgery is rare but causes high rates of morbidity and mortality. Knowledge about postoperative mediastinitis due to S. marcescens is limited. The purpose of this work was to study the clinical presentation, management and outcome of an outbreak of postoperative sternal infection due to S. marcescens. METHODS During a 7-week period, a total of 54 patients underwent open heart procedures in our hospital. A postoperative wound infection caused by S. marcescens was diagnosed in 10 patients. We performed a clinical study to investigate patient characteristics and outcomes as well as the possible source of the infection. RESULTS The mean age of the infected patients was 74.5 ± 10 years. Mediastinitis was present in 6 cases, superficial wound infection in 3 and isolated bacteraemia in 1. Purulent exudate through the sternal incision was observed in all infected cases except in 1 patient, who presented only with bacteraemia. Serratia marcescens was isolated from the samples taken from all infected wounds. The mean time elapsed between the operation and the isolation S. marcescens was 5.9 ± 2.4 days. Response to treatment was favourable in all cases except 1, who died. Contamination of the aqueous chlorhexidine solution used to prepare the patients’ skin with S. marcescens was reported. Microbiological studies demonstrated that S. marcescens strains isolated from patients and from the aqueous chlorhexidine solution belonged to the same clone. CONCLUSIONS The use of an aqueous chlorhexidine solution contaminated with S. marcescens caused an outbreak of postoperative sternal wound infections. The time elapsed between wound contamination and signs of infection was brief, but the systemic inflammatory response and tissue necrosis were limited. Alcohol-based solutions are recommended for the prevention of surgical site infections.

Global population structure of the Serratia marcescens complex and identification of hospital-adapted lineages in the complex

“…It causes a range of nosocomial infections, such as pneumonia, urinary tract infections, bacteremia, meningitis and endocarditis, particularly in immunocompromised patients [1]. Many hospital outbreaks of this opportunistic pathogen, which sometimes occur recurrently, have also been reported [2][3][4][5][6][7][8]. While Sma is known to be naturally resistant to penicillins and first-and second-generation cephalosporins, strains showing higher levels of antimicrobial resistance (AMR) have also emerged and spread widely [9,10].…”

Gram-negative bacteria as a cause of mediastinitis after cardiac surgery

“…), but increasing PSM caused by Acinetobacter , Pseudomonas aeruginosa and Stenotrophomonas maltophilia have also been described [7 ▪▪ ,8,11,14,15,17]. Of interest that an outbreak of PSM caused by Serratia marcescens because of contamination of the aqueous chlorhexidine solution used to prepare the patients’ skin has been reported [18]. Evidence of increasing multidrug-resistant (MDR) GNB infecting DSWI is a great concern and are likely to increase in number in future years [17,19,20].…”

Serratia Bacteremia After Intravenous Propofol: Two Case Reports

“…Serratia türleri, vücuda giriş yerine bağlı olarak pnömoni, kan dolaşımı infeksiyonu, menenjit, üriner sistem infeksiyonu, cerrahi yara infeksiyonu, endokardit, kateter ilişkili infeksiyonlar gibi farklı lokalizasyon ve şiddette infeksiyonlara neden olabilmektedir. Oluşturdukları en ciddi infeksiyonlar kan dolaşımı infeksiyonlarıdır (2,9).…”

“…Serratia türleri hastane ortamında kolayca kolonize olup, yoğun bakım ve yenidoğan üniteleri gibi immunsuprese ve kritik durumdaki hastaların izlendiği bölümlerde, morbiditesi ve mortalitesi yüksek salgınlara neden olabilmektedir (5). Serratia türleri ile gelişen nozokomiyal salgınlarda bir diğer önemli kazanım yolu antisepsi için kullanılan solüsyonla-rın ve parenteral yolla kullanılan medikal ilaçların kontamine olmasıdır (9)(10)(11)(12). S. marcescens ile gelişen ilk nozokomiyal salgın 1951 yılından tanımlanmış, sonraki yıllarda giderek artan sayıda bildirimler olmuştur (2).…”

“…İspanya' da 2014 yılında açık kalp cerrahisi uygulanan hastalarda, %2'lik sıvı klorheksidin solüsyonlarının, üretim aşamasında S. marcescens ile kontamine olmasına bağlı sternal yara infeksiyonu ve katater ilişkili kan dolaşımı infeksiyonu salgınları bildirilmiştir (9)(10)(11). Amerika Birleşik Devletleri'nde ikibinli yıllarda çok sayıda eyalette, intravenöz magnezyum sülfat ve heparin solüsyonlarının üretim aşamasında S. marcescens ile kontaminasyonunun neden olduğu kan dolaşımı infeksiyonu salgınları saptanmıştır (12,17).…”