Infection Control Strategies to Avoid Carbapenam Resistance in Hospitals Victor Lim International Medical University Malaysia
Outline of Lecture 1. Carbapenam resistance 2. Epidemiology of carbapenam resistance 3. Control strategies i. Institutional strategies ii. Clinician strategies
Carbapenams Class of betalactam antibiotics Imipenam, meropenam, doripenam, ertapenam Very broad spectrum Stable to many betalactamases including ESBLs Last line of defence against resistant Gram negative organisms Unfortunately resistance has become a problem globally
Mechanisms of resistance Organism Enterobacteriaceae Mechanism of resistance ESBL + porin loss Carbapenemase. P. aeruginosa Porin loss Efflux mechanism Carbapenemase Acinetobacter spp ESBL + porin loss, Carbapenemase
Carbapenemases Betalactamases that inactivate carbapenams Most important mechanism of resistance Classification Enzyme Common Bacteria Class A (serine based) KPC Enterobacteriaceae Class B (metallo-b-lactamse) IMP, VIM, NDM P. aeruginosa Enterobacteriacea Acinetobacter spp. Class D OXA-48 Acinetobacter spp.
NDM Epidemiology of Carbapenemases Geographic distribution Originated in India and Pakistan; now spread globally Molecular Epidemiology Plasmid spread more important than clonal spread among patients. VIM Global Plasmid spread more important than clonal spread IMP Global Plasmid spread more important than clonal spread KPC USA, Europe Clonal spread eg K. pneumoniae ST258 lineage. OXA-48 Turkey, Middle East, N Africa Mixture of plasmid and clone spread.
Epidemiology of CROs
Sources of infection Patients Colonised (majority Primary site of colonisation is the lower gastro-intestinal tract Duration of colonisation is unknown, but is possibly life-long Infected Environment CROs can survive on environmental surfaces and equipment
Transmission of CROs Contact Hands of Health care worker Infected or colonised patient New patient Environment Equipment
Risk Factors for Patients Prolonged hospitalisation Previous antibiotic therapy Betalactams Quinolones Invasive devices Urinary catheters Elderly Severe underlying disease Intensive care Mechanical ventilation
Risk Factors for Transmission Diarrhoea or faecal incontinence Enterostomies Discharging wounds Catheterised patients with CRE colonisation of the urinary tract Patients who are incapable of maintaining their own personal hygiene
Control Strategies for carbapenem resistant organisms (CROs)
Infection Control Strategies Administrative support Education and training Surveillance and Early detection Contact precautions Antibiotic stewardship
Administrative Support Implementing system changes Governance and management structure Resource allocation staff, facilities, IT support Enforcement Education and Training Creating awareness Encourage behaviour change through better understanding of the problem Hand hygiene campaigns Training in infection control Training in antibiotic usage
Surveillance and Early detection Institution needs to establish a surveillance system for CROs Use of routine antibiograms & carbapenemase screening tests CRO incidence rates CRO infection rates Ensure laboratory capability in detecting carbapenem resistance Molecular typing for epidemiological purposes
Susceptibility breakpoints G Levy Hara et al. J Chemotherapy 2013
Laboratory Detection of carbapenamase
Detection of carbapenamase
Detection of carbapenamase http://www.cdc.gov/hai/pdfs/labsettings/kpc-ndmprotocol-2011.pdf
Surveillance screening Rectal swabs Point prevalence screening in selected units Screening of patients with epidemiological links to an index case Active screening of high risk patients Screening of staff not required Expensive and resource intensive strategy No good evidence of any impact of screening on preventing spread of CROs
Contact precautions Isolation or cohorting Single room with bath Hand hygiene Single most important measure to prevent transmission Antiseptic, proper sinks, hand drying Alcohol based hand rub Audits Personal protective equipment Gloves and gowns (single use) when attending to patient
Contact precautions Patient equipment Single use items where possible Dedicated non-critical equipment eg stethoscope Proper disinfection/sterilisation of reusable items Alcohol disinfectant wipes for specialised medical equipment eg X-rays, ECG, ultrasound Environmental cleaning Chlorine-based disinfectant to clean all surfaces especially those likely to come into contact with hands
Devices Invasive devices increase the risk of acquiring CROs Minimise use of devices Monitor and review use regularly and remove when no longer necessary When in place ensure proper nursing care of devices like urinary catheters and intravascular lines
Antibiotic stewardship Antibiotic stewardship programme Education Academic detailing and immediate concurrent feedback Focus on antibiotics which have been associated with the emergence of CROs Carbapenems 3 rd and 4 th generation cephalosporins Quinolones Optimise antibiotic usage choice, dose, route, duration De-escalation strategy
Treatment Carbapenem resistant organisms are also usually resistant to other betalactams, aminoglycosides and quinolones Polymyxin, tigecycline and fosfomycin Aztreonam for IMP, VIM and NDM if organism does not produce AmpC or ESBL Ceftazidime, cefotaxime and aztreonam for OXA-48 Gentamicin for ST258 Kelbsiella pneumoniae (KPC) Combination therapy recommended
Conclusion Carbapenem resistant organisms are the latest superbugs Limited options for treatment Need efficient infection control measures Good surveillance Early detection Contact precautions Antibiotic stewardship Good laboratory support