First toxic shock outbreak of MRSA reported
Toxic shock symptoms appear in four of 27 infected
The first nosocomial outbreak of a toxic shock-producing strain of methicillin-resistant Staph yl o coccus aureus (MRSA) was recently reported in St. Louis at the annual conference of the Society for Healthcare Epidemiology of America (SHEA).
The outbreak at Moore Regional Hospital in Chapel Hill, NC, included 27 patients with nosocomial MRSA infections, reported Karen Hoffmann, RN, MS, CIC, clinical instructor in the division of infectious diseases at the University of North Carolina School of Medicine in Chapel Hill. Of the 27 infected patients, four developed toxic shock symptoms and one of those died. Symptoms included fever, skin rash, hypotension, and multi-system involvement.
First recognized in 1927 and called staphylococcus scarlet fever, toxic shock syndrome was linked to tampon use in the 1980s. In 1981, the first case of nosocomial toxic shock syndrome was described involving a patient undergoing knee surgery. The outbreak reported at SHEA shows that the toxic strains of MRSA can be transmitted nosocomially to a cluster of patients.
Infection may have occurred via hand carriage
Most of the patients were associated with surgical procedures, and there was some evidence that the outbreak may have begun with one patient serving as a reservoir to infect others via hand carriage by health care workers, she said. The MRSA isolates among the 27 patients and three colonized nurses were identical, she reported.
"These were the primary workers on the units that took care of these patients, so they were definitely linked," Hoffmann told SHEA attendees.
The outbreak began in April 1996, when two patients in a cardiovascular intensive care unit were noted to have profuse diarrhea with stool cultures positive for MRSA. Within several days, two other nosocomial infections with MRSA were noted in patients who had undergone coronary artery bypass graft procedures, and the outbreak investigation began. Intervention efforts begun in April and May included surveillance of cultures from health care workers. A second group of MRSA cases was found between October and December of last year, and further interventions were attempted. The number of cases was telling, as the hospital only had nine nosocomial MRSA cases in 1995 and six in 1994, Hoffmann said.
Through the overall outbreak period from February 1996 through January 1997, 38 nosocomial MRSA isolates were noted, including 27 identical isolates that produced the toxin protein associated with toxic shock syndrome. A total of six hospital units were eventually involved, suggesting cross-transmission between patients. Major infection sites include seven in the blood, six wound infections, six in the respiratory tract, and three in the gastrointestinal tract.
Control measures included increased surveillance for cases, handwashing education, contact isolation measures, disinfection of shared patient equipment, and use of waterless, antiseptic hand cleaning lotion due to poor sink access in ICU. In addition, all patients previously identified with MRSA are now isolated on admission until culture-negative. All health care workers with positive MRSA nasal cultures have been removed from direct patient care activities until their cultures are negative. Colonized employees were treated under a protocol that included mupirocin and rifampin, and all recultured negative within 10 to 14 days following the therapy.
"We believe this the first report of an outbreak with MRSA associated with toxic shock syndrome in a community hospital," Hoffmann said.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content