MRSA and the Cook County Jail: Analysis of Isolates That May Be From a Reservoir of Community- Associated Infections

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MRSA and the Cook County Jail: Analysis of Isolates That May Be From a Reservoir of Community- Associated Infections Lena Kuo, MD, Robert Daum, MD, Susan Boyle, PhD, Michael David, MD, Daniel Kim Department of Pediatric Infectious Disease Introduction Hypothesis Results Results Conclusions • Staphylococcus aureus is a common cause of skin and soft tissue infections, pneumonia, septic arthritis, osteomyelitis, and sepsis • Methicillin-resistant Staph aureus (MRSA) has become an increasingly prevalent threat to public health in the US and worldwide • MRSA was originally confined to hospitals, health care institutions • Increasingly, MRSA isolates with distinct genotypes have caused community- associated infections and outbreaks, notably in populations without traditional risk factors • Reservoirs for community- associated MRSA have yet to be identified • Outbreaks of CA- MRSA have been identified in multiple settings with crowding and/ or poor hygienic conditions, including: athletic teams, daycare, military, jails/prison • Detainees in prisons and jails are well-recognized reservoirs for tuberculosis • Infectious agents that are spread by casual contact, frequently isolated in asymptomatic carriers, and difficult to eradicate may spread among the prison and jail population and then into the community (such as MRSA) • Detainment at a jail or prison has become increasingly prevalent in the adult population; 1 in 110 and 1 in 1656 women have been in jail or prison; 10.4% of black men between 25-29 were imprisoned • Monitoring of etiologic agents of skin infections at the Cook County Jail between March 2004 and August 2004: 70.9% (122/ 172) skin infections grew MRSA Jail serves as a reservoir for CA- MRSA in the community of Chicago Of the jail isolates molecularly characterized, the majority are: • Resistant to erythromycin and ß-lactam antibiotics • MLST sequence type 8 • SCCmec type IV 1. Antibiotic resistance profile is in concordance with the antibiotic resistance profile found in CA-MRSA strains 2. ST-8 is a very common sequence type found in CA-MRSA infections 3. ST-1 has been associated with severe staphylococcal sepsis in children (MW2 CA-MRSA in North Dakota, 1999) 4. SCCmec type IV is commonly found in CA-MRSA isolates 5. Initial results of molecular characterization of jail isolates suggest that MRSA strains found in the jail represent the same, or closely related, strains found in the community of Chicago III. SCCmec Typing (9 isolates) • Antibiotic Resistance Profiles (18 isolates) • • 72% were resistant to only erythromycin and ß-lactams • • 11% were resistant to ß- lactams only • • 17% were were multi- drug resistant • Multilocus Sequence Typing (37 isolates) Specific Aims mecA ccr 1-3 mecR1/PB PVL • By multilocus sequence typing (MLST), SCCmec typing, and toxin gene identification (PVL), preliminarily determine: • The colonizing clones of MRSA found within the Cook County Jail; • Compare predominant clones found in the jail to those found in the community Materials 61 MRSA isolates from infected detainees at the Cook County Jail, collected between March- December, 2004 Methods Future Directions • I. Antibiotic Resistance Profiling • II. Multilocus Sequence Typing (MLST): • Characterization of bacterial isolates using internal fragment sequences of seven housekeeping genes • Sequences are between 450-500 bp long • Different sequences are assigned as different alleles, determined by comparing sequences to known alleles in the MLST database • Alleles at the 7 loci define the allelic profile, or sequence type • Unambiguous descriptor for the S. aureus genotype • Secondary to the nature of the housekeeping gene, allelic profile of isolates change very slowly over time • MLST can identify relatedness of isolates and identify clones with serious disease • III. SCCmec Typing: • SCCmec: “Staphylococcal chromosomal cassette mec,” a mobile genetic element that contains the mecA region • mecA gene: encodes PBP2a, a penicillin binding protein that has decreased affinity for ß-lactam antibiotics • SCCmec are classified into 5 types based on polymorphisms on conserved genes •Determine MRSA and MSSA new colonization rate of detainees at the Cook County Jail •Determine risk factors associated with new MRSA or MSSA colonization at the Cook County Jail •Characterize the clones associated with new colonization MLST typing of jail isolates P11- P17; confirmation gel electrophoresis of PCR product • Of the 37 isolates characterized, MLST were as follows: • 86.5% (32/37) were type 8 • 8.1% (3/37) were type 5 • 2.7% (1/37) were type 1 • 2.7% (1/37) were type 474 Summary of Culture Results Cermak Health Services March- August 2004 References C P3 P4 P5 P27 C P57 P58 P59 P60 P61 Adcock P, Pastor P, Medley F, Patterson J, Murphy T. Methicillin-Resistant Staphylococcal aureus in Two Daycare Centers. J Infect Dis 1998; 178: 577-80. Baillargeon J, Kelley MF, Leach CT, Baillargeon G, Pollack BH. Methicillin-Resistant Staphylococcal aureus Infection in the Texas Prison System. Clin Infect Dis 2004; 38e92-95. Bonczar TP and Beck AJ. Lifetime Likelihood of Going to State or Federal Prison. Bureau of Justice Statistics, Office of Justice Programs, 1997. Daum R, Ito T, Hiramatsu K, Hussain F, Mongkolrattanothai K, Jamklang M, Boyle-Vavra S. A Novel Methicillin-Resistance Cassette in Community-Acquired Methicillin-Resistant Staphylococcus aureus Isolates of Diverse Genetic Backgrounds. JID 2002; 186: 1344-7. Ma XX, Ito T, Tiensasitorn C, Jamklnag M, Chongtrakool P, Boyle-Vavra S, Daum RS, Hiramatsu K. A Novel Type of Staphylococcal Chromosome mec (SCCmec) Identified in Community-acquired methicillin-resistant Staphylococcal aureus strains of Chicago area. Antimicrob Agents and Chemother 2002; 46: 1147-52. Mongkolrattanothai K, Boyle-Vavra S, Kahana MD, Daum RS. Severe Staphylococcal aureus Infections Caused By Clonally-related Community- qcquired Methicillin-suseptible and Methicillin-Resistant Isolates. Clin Inf Dis 2003; 37: 1050-8. SCCmec typing of jail isolates P3-P5, P27, P57-61 (from left to right: ladder, positive control, isolates P3-5, P27, positive control, P57-61) • Of the 9 isolates characterized by SCCmec typing, 89% (8/9) were SCCmec type IV • 89% (8/9) were PVL positive Daum et al. JID 2002; 186: 1344-7 Cermak Health Services, March-August 2004