1 / 19

S. aureus nasal carraige

S. aureus nasal carraige. Post – operative wound infection Pneumonia Line infection CAPD/HD infection Infections in immunocompromised host. Kluytmans, J. Infect Dis 1995; 171:216 Weinstein, NEJM 1959; 260: 1303 Luzar, NEJM 1990; 322: 505 Yu, NEJM 1986; 315:91 Von Eiff; NEJM 2001; 344: 11.

jenn
Download Presentation

S. aureus nasal carraige

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. S. aureus nasal carraige • Post – operative wound infection • Pneumonia • Line infection • CAPD/HD infection • Infections in immunocompromised host Kluytmans, J. Infect Dis 1995; 171:216 Weinstein, NEJM 1959; 260: 1303 Luzar, NEJM 1990; 322: 505 Yu, NEJM 1986; 315:91 Von Eiff; NEJM 2001; 344: 11 Majority of infections are endogenous

  2. Staph aureus nasal carraige • Nasal carraige appears to be natural ecologic niche, though axilla and groin/perineum can also be common • Elimination from nares appears to result in subsequent disappearance from other sites Moss, Lancet 1948; 1: 320 Noble, J Hyg (lond) 1967; 65: 567 Doebbeling, J Chemother 1994; 6 (supple 2):11 Casewell, J Antimicrob Chemother 1986; 17: 365 Reagan, Ann Intern Med 1991; 114: 101

  3. Longitudinal surveys of Staph aureus carraige in healthy adults • Nasal carraige in 20-55% • Persistent carraige: 10-35%, often same clone • Intermittent carraige: 20-75%, dif. clones • Never carry: 5-50% • More common in children, reasons for pattern shift unknown Gould, J Hyg (lond) 1954; 52: 304. Hu; J Med Microbiol 1995; 42: 127 Armstrong-Esther, Ann Hum Biol 1976; 3: 221. Goslings, Arch Int Med 1958; 102: 691 Hoffler, Med Microbiol Immunol 1978; 164: 285. Maxwell , Am J Surg 1969; 118: 849 Riewerts Eriksen, 1995; 115:51

  4. Persistent carraige • Higher numbers than in intermittent carriers • Persistent carraige seems to exclude other staph strains as clone is stable. Better match, specific receptors? • 2 quantitative cultures needed to predict carrier state • 7 cultures needed to discern none vs intermittent carriers (Nouwen, 2001)

  5. Lipoteichoic acid Protein A MSCRAMM..microbial surface components recognizing adhesive matrix molecules Mucin IgA, glycolipids, gangliosides Surfactant protein A Hydrophobic interactions Surface charge Bacterial interference: coag neg staph, coryneforms, other S aureus Agr, Sar Bacterial Determinants of S.aureus Nasal Carraige

  6. Ethnicity Males>females Young> old Hormonal status Carrier epithelial cells > non-carrier epithelial cells Eczema pt cells > normals Hospital exposure Paired partners/concordance DM,ESRD, IVDU, allergies, liver dis, HIV, WBC dysf’n, Wegeners, sinusitis Defensins Cigarettes (-) Host factors

  7. Intranasal mupirocin to prevent post surgical infection: systematic review. JAC 2008 61; 254 RR 0.55, 95% CI 0.34-0.89, p <0.02

  8. CHG,mupirocin,Rif/Doxy for decolonization. Simor et al, CID 2007; 44:178

  9. “decolonization” = to change carraige status, based on cultures Decolonization isn’t eradication “suppression” = to temporarily reduce skin shedding and microbial ‘load’ All of these manoeuvres to reduce body carraige are still experimental. Variables that affect carraige are not all known at present Use of these strategies should be part of an investigative program Why consider decolonization or suppression?

  10. Screen for MRSA colonization Admission screen Prevalence screen Isolate, barrier, cohort Suppression, arrest transmission, ? decolonize Decolonization clinic Outpatient referrals

  11. Rationale for decolonization • Reduce recurrent infection in carriers • If body is decolonized, where other normal flora is able to return to various sites, then these persons will not continue to be a source of organisms to colonize others • Decolonization may be too laborious in hospitalized acute care patients. In this setting, a more limited objective of load reduction might be attempted. • Transmission and reduced case rates, reduced isolation needs are to be determined.

  12. Persistent carriage is documented Risk factors for failure: elderly, wounds, skin conditions, DM (treat) Compliance Nasal mupirocin [fucidin, 0.2% CHG] x 7-10 d Body baths CHG 4% x 7-10 days Systemic Rx: SxT, Doxycycline, Clinda, Rifampin Linen changes Under/clothes changes House cleaning quats or bleach Household contacts Components of MRSA decolonization

  13. Cultures • Confirm persistent carraige at various sites • Nares, throat, body Z/axillae, groin/perirectal/vaginal, hands, lesions • 1+ to 4+ on agar surface (semi Q, also broth amplification) • Screen of household contacts, if positive include as new subject • PFGE, molecular testing re virulence markers

  14. Overall strategy in CHR • Relatively closed system, AcuteLTC/ community (bi-directional) • Increase screening to targeted admission screens, prior point prevalence to cohort patients • Investigate strategy of microbial load reduction to determine if this would limit transmission. Can it allow modification of barrier techniques? • After discharge, stable  refer to decolonization clinic to attempt clearance of carraige, as a study program.

  15. Dialogue with administration to indicate that rates are rising despite ‘regular’ infection control approach [prior assessment that we are failing to contain rising rates] Obtain high level support / funds to conduct wider screening Model screening/search and suppress approach (1000 pts) Establish clinic for discharged MRSA pts to study decolonization What’s been done so far in CHR?

  16. The clinic… • Temporary UCMC 6, AGW5, HPTP FMC, two ½ days/ week 0.25 RN/ID staff, needs 1.0 FTE NP, needs a physician of note. • 0.5 FTE Secretarial/ Patient scheduler, needs to be increased to 1.0 FTE • Cultures: SemiQ at all sites, low count broth cultures • Bacterial interference as possible last resort mode of treatment • Supplies: CHG scrubs/baths, Nasal Rx, Quats, Info,

  17. Follow up • After confirmation of persistent carraige, family contact cluster, book for start of decolonization • Treat for 7 days with topicals Nasal / skin if no lesions, treat with added antimicrobials if lesions. Arbitrary re duration. 2-3 weeks if deep seated. • Follow up cultures 1, 4, 12 weeks, if possible 6 months. General concensus re 12 weeks/90 days as reasonable breakpoint for duration of followup

  18. 314 persons referred for screening including family clusters 76 different families Variable compliance Aim for 1 week, 1 mo, 3 mo, 6 mo. F/U Uncomplicated, no ulcers, normal skin , mup S = good success rate ~75% If mup R, high failure/recurrence Psoriasis, eczema is high risk of failure caMRSA 10 appears more difficult to clear, more recurrences. Results of Decolonization in CHR

  19. Labour intensive for patients, esp. cleaning household/laundry Dermatology consultative care essential for patients with skin disorders Still do not have a formula that guarantees success. Novel therapies? Photoactive destruction of MRSA? Need for susceptibilities Need to study ecology of nose/skin, adherence factors, strain differences. CHG and nasal treatments to suppress/eradicate, also deplete normal flora. Summary of decolonization

More Related