MONTANA: A Summary of Select Antimicrobial Resistance Data
Antibiotic-resistant infections have become significant threats to citizens of MONTANA:
Drug-resistant Staphylococcus aureus:
- Although primarily affecting ill people in hospitals, methicillin-resistant Staphylococcus aureus
(MRSA), a drug-resistant bacteria, are infecting a growing number of
people in the community and outside hospitals, including healthy
athletes and children. A recent study in the Journal of the American Medical Association
demonstrates that MRSA alone infects more than 94,000 people and kills
nearly 19,000 annually in the United States – more deaths than those
caused by emphysema, HIV/AIDS, Parkinson’s disease, and homicide.2
- Hospitalizations for or complicated by MRSA cost nearly double that
for non-MRSA stays – 14,000 for MRSA stays compared with $7,600 for
non-MRSA stays. The average length of stay in the hospital for a
patient with MRSA infection was more than double that for non-MRSA stays
– 10.0 days versus 4.6 days.3
- Data from Montana indicate that the incidence of MRSA is increasing. Surveillance data of S. aureus
isolates from Montana’s clinical laboratories spanning a ten year
period, illustrate this point. Between 1996 and 2006, the number of
MRSA isolates detected increased from 378 to 2,664. Over this same
period, the percentage of all S. aureus isolates found to be MRSA has
more than doubled from 17% to 40%.4
Drug-resistant “gram negative” bacterial infections:
- Serious and life-threatening infections due to antibiotic resistant
“gram negative” bacteria are on the rise across the United States. Gram
negative bacteria primarily are differentiated from gram positive
bacteria, like MRSA, by a cell wall that is particularly adept at
preventing antibiotics from entering the bacteria. These infections,
primarily acquired in hospitals and long term care settings, are
extremely difficult to treat and cause significant numbers of illnesses
and deaths. Bacteria in this group include: Escherichia coli (E.
coli), Klebsiella pneumonia, Pseudomonas aeruginosa, and Acinetobacter.
- In March 2009, CDC published guidelines for detection and control of
E. coli and Klebsiella species with increasing resistance to a subclass
of antibacterial drugs known as carbapenems. Carbapenems are among the
most potent antibiotics currently available and are often considered
the “last line of defense” in the treatment of antibiotic resistant
bacteria. Studies have shown that the mortality rate from infections
caused by carbapenem resistant Klebsiella species is roughly 40%. CDC
described this problem as “another in a series of worrisome public
health developments regarding antimicrobial resistance among
gram-negative bacteria [that] underscores the immediate need for
aggressive detection and control strategies.”5
- Noteworthy, these organisms are difficult to detect with the
automated testing systems currently used in most hospital laboratories.6
- Of critical importance, there are few to no approved antibacterial
drugs currently available to treat many gram negative bacterial
infections and few to no new drugs in the pipeline; drug discovery in
this area is extremely difficult due to challenges in overcoming the
gram negative bacteria’s cell wall.
Other antimicrobial resistance issues:
- Clostridium difficile (C. diff) is spawning
infections in hospitals in the U.S. and abroad that can lead to severe
diarrhea, ruptured colons, perforated bowels, kidney failure, blood
poisoning and death. It is a common cause of antibiotic-associated
diarrhea, accounting for 15-25% of all episodes. CDC estimates there
are 500,000 cases of C. diff. infection annually in the U.S.,
contributing to between 15,000 and 30,000 deaths. Elderly hospitalized
patients are at especially high risk and mortality in these patients may
exceed 10%. The disease is very difficult to treat and recurs in at
least 20% of cases, even when treated appropriately.
- Deaths from C. diff have fluctuated in Montana over the past few years. There were 3 in 2001, 3 in 2002, 3 in 2003, 6 in 2004, and 2 in 2005.7
- In 2003, the State of Montana Department of Public Health and Human
Services Public Health Laboratory (PHL) surveyed laboratories in the
State of Montana regarding antimicrobial resistance for the preceding
year. This survey was undertaken as a follow-up to a similar survey
conducted in 1996 that collected data about reported AMR patterns during
that year.
- The levels of resistance to select antimicrobials reported for Streptococcus pneumoniae
during 2002 has remained stable over the 6-year time period; however,
the levels of resistance to ciprofloxacin, erythromycin, and penicillin
has increased slightly over this period.8
- The levels of resistance to select antimicrobials for Staphylococcus aureus in 2002 include very high levels of penicillin-resistant S. aureus
(90-91%). For most of the antimicrobial agents that were included on
both the 1996 and 2003 surveys, the levels of resistance has remained
stable over the 6-year time period; however, the level of resistance to
ciprofloxacin has increased slightly over this period.9
- The levels of resistance to select antimicrobials for Enterococcus
species include 70 percent resistance to tetracycline, 40 percent
resistance to ciprofloxacin, and 32 percent resistance to levofloxacin.10
- The levels of resistance to select antimicrobials for Pseudomonas aeruginosa
include 99 percent resistance to ampicillin, 97 percent resistance to
sulbactum, and 27 percent resistance to ciprofloxacin and levofloxacin.11
Public health laboratory capacity:
A key factor in Montana’s ability to detect, monitor and control
antimicrobial resistance is its public health laboratory capacity.
Across the nation, increasing cases of antimicrobial resistance are
currently swamping the ability of each state's public health laboratory
to keep pace. There has been limited funding in the past for antibiotic
resistance education programs and surveillance, and even this limited
funding is on the decrease. Approximately only half of state public
health labs can provide some basic resistance testing. Like many
states, Montana lacks the targeted technical ability to detect and
characterize emerging resistance patterns promptly in a range of
pathogens. Therefore, such resistant organisms continue to spread
unrecognized and unimpeded throughout the state.
1Dr. Fred Tenover, quoted in “The Bacteria Fight Back”
Science, July 18, 2008.
2R. Monina Klevens et al. “Invasive Methicillin-resistant
Staphylococcus aureus Infections in the United States,”
JAMA, October 17, 2007: 1763-1771.
3Elixhauser, A. and Steiner, C.
Infections with Methicillin-Resistant Staphylococcus Aureus (MRSA) in U.S. Hospitals, 1993–2005. HCUP Statistical Brief #35. July 2007. Agency for Healthcare Research and Quality.
4The State of Montana Antimmicrobial Susceptibility Testing Survey 2007, August 2007.
http://mara.mt.gov/documents/ASTReport-2007Final.pdf (p14)
5 CDC MMWR “Guidance for Control of Infections with Carbapenem-Resistant or Carbapenemase-Producing
Enterobacteriaceae in Acute Care Facilities” March 20, 2009 / Vol. 58 / No. 10
6 K. F. Anderson, et al.; Evaluation of Methods To Identify the
Klebsiella pneumoniae Carbapenemase in
Enterobacteriaceae; Journal of Clinical Microbiology, August 2007, p. 2723-2725, Vol. 45, No. 8
7 CDC Wonder Death Certificate Data, cited in a July 28, 2008 communication to Senator Sherrod Brown
8Antimicrobial
Susceptibility Patterns in Montana: A Survey of Laboratories in 2002,
Montana Department of Public Health and Human Services, July 2004.
9 ibid
10 ibid
11 ibid