Serratia marcescens Outbreak After Drug Tampering in US Hospital

serratia marcescens
serratia marcescens
A hospital nurse was found responsible for an outbreak of Serratia marcescens as a result of an illegal opioid diversion.

A hospital nurse was found responsible for a cluster outbreak of Serratia marcescens as a result of an illegal opioid diversion, according to the findings of an investigation published in Infection Control & Hospital Epidemiology.

At the University Hospital in Madison, WI, 5 patients admitted to 5 different wards had developed the same gram-negative bacterial strain within 48 hours of admission between March 2 and April 7, 2014. Soon after this discovery, the staff found 4 hydromorphone syringes and 6 morphine syringes in an automated medication dispensing cabinet that had been compromised.

A controlled substance diversion investigation (CSDI) resulted in order to trace the origin of the S marcescens outbreak. 

Hospital epidemiologists reviewed blood cultures and molecular fingerprinting and concluded there was a possible link between the cluster infections and the opioid diversion. Additional analysis indicated that 4 of the 5 exposed patients had been infected with S marcescens during a brief post-op stay in the Post-Anesthesia Care Unit, where the suspected nurse worked. The fifth patient (the nurse’s father) had been exposed to S marcescens prior to being admitted.  

Upon evaluation of the cases, hospital epidemiologists associated the outbreak with the tampered syringes as the employee had accessed the cabinets where the syringes were kept. The investigation found that that the nurse had replaced the active medication with saline or another solution. All of the patients recovered except one who died from a sepsis infection. The nurse was subsequently terminated and no other cases of S marcescens were identified.

Nasia Safdar, MD, PhD, senior author and hospital epidemiologist at the University Hospital stated, “Our experience highlights the importance of active monitoring systems to prevent hospital-related drug diversion, and to consider this potential mechanism of infection when investigating healthcare-associated outbreaks related to gram-negative bacteria.” Following this incident, the hospital put in place more diversion detection and security strategies, including tamper-evident packaging and security camera installations.

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Schuppener LM, Pop-Vicas AE, Brooks EG, et al. Serratia marcescens bactermia: nosocomial cluster following narcotic diversion. Infect Control Hosp Epidemiol. 2017 Jul 6:1-5. doi: 10.1017/ice.2017.137.

This article originally appeared on MPR