Biofilm Induction of Cellular Senescence Dr. Matthew Regulski DPM Director, The Wound Institute of Ocean County NJ Partner, Ocean county Foot and Ankle Surgical Associates Toms River NJ APMA National Meeting 2018, Washington D.C.
Don ’ t Stop Your Curiosity
INFECTIONS COST THE HEALTHCARE SYSTEM Estimated cost of hospital-acquired infections in the United States 9 . 2,000,000 estimated infections per year X $15,275 (Average additional costs for contracted infections) = $30.5 billion In 2014, 721 hospitals had their Medicare reimbursement lowered 1% — roughly $373 million in penalties — for having high hospital-acquired infection rates. 10 In 2014, 18 percent of Medicare patients who had been hospitalized were readmitted within one month. Roughly two million patients are readmitted every year, costing Medicare $26 billion. Officials estimate $17 billion of that comes from potentially avoidable readmissions. 10 Healing wounds quickly to full closure will not only save the healthcare system millions of dollars every year but improve the quality of life for millions of people living with chronic wounds. 9. The Committee to Reduce Infection Deaths. The cost of infection. Preventing Infections Makes Hospitals More Profitable. http://www.hospitalinfection.org/cost_of_infection.shtml. Last accessed January 25, 2017. 10. Kaiser Health News. Medicare Fines 2,610 Hospitals In Third Round Of Readmission Penalties. Jordan Rau. http://khn.org/news/medicare-cuts-payments-to-721-hospitals-with- highest-rates-of-infections-injuries/. Last updated October 2, 2014. Last accessed January 25, 2017. 3
Medical Biofilms Medical Biofilm US Incidence Annual Cost Diabetic foot ulcers (P) 3 M 50,000 deaths, 30% of hospital cost for diabetics Venous leg ulcers (P) 2.5 M General Infections Decubitus ulcers (P) 3-5 M (P) 27%NH > 50,000 Surgical site infections 500,000 $5-10 B, 5,000 deaths Burn wounds 1.1 M 15,000 deaths Chronic meningitis 1,400-2,800 140-390 deaths Bacterial prostatitis (P) 162,800 All odontogenic infections Chronic tonsillitis 11,000 $121.5 M Gallstones 430,000 $5 B Crohn’s disease 36,000-60,000 Ulcerative colitis 24,000-40,000 COPD (P) 30 M $37.2 B, 120,000 deaths Bronchiolectasia 110,000 Pneumonia (non-VAP) 1.2 M $14-$25 B, 54,000 deaths Medical Biofilm US Incidence Annual Cost Nosocomial Vascular graft infection 16,000 $640 M Cardiac pacemakers 4,000-20,000 Peritoneal dialysis peritonitis ~20-25,000 on CPD Ventilator acquired pneumonia 135,000 $1.5 B, 61,000 deaths 100s of thousands * Endotracheal tubes $5 B Urinary catheter cystitis Millions 4,500 deaths Central venous catheters 250,000 $296 M-$2.3 B, 30-62.5 K deaths Total 20 Million $100 B, >500k deaths
Medical Biofilms Context For Comparison Disease Incidence Annual Cost Cardiovascular Disease 2.28 M per year $431.8 B, 650,000 deaths Cancer 1.5 M per year $206.3 B, 550,000 deaths Diabetes 1.5 M per year, ages 20+ $132 B, 73,000 deaths Medical Biofilm > 10M per year > $200 B, > 500,000 deaths
Biofilm EPS Structure (P. aeruginosa) – Ca+ Bridging Ca ion – These polymers are water-soluble – they should go into solution in saline! – This material has calcium-ion bridging in it to produce gelling • In effect, this bridging works as cross-links would work in a traditional thermoset polymer. As such, even if a good solvent for this material were found, it would not be able to bring the EPS into solution – it would swell the polymer, but the bridging would prevent the individual polymeric strands from going into solution. 7
Biofilm Development Masako,K Journal of Dermatologic Science June 2005
Biofilm Detachment
Biofilm Infection • (a) Bacteria adhered to surface Surface selects (but is not necessary) for biofilm formation • (a) Direct visualization of biofilm morphology The current “ gold standard ” for diagnosing biofilm • (a) Confined to a particular location Biofilm seems to limit its size (quorum sensing) • (a) Resistant to appropriate antibiotics A hallmark of biofilm is high resistance to antibiotics • (b)Resistant to biocides A hallmark of biofilm is high resistance to biocides • (b)Large number with high diversity in a host lesion • (b)Infections that wax and wane with exacerbations (a)Parsek Annu. Rev. Microbiol. Vol57, 2003 • (b)Secondary signs of infection (b) Wolcott JWC Vol19(2), 2010 Costerton and Stewart Sci Am Vol 285, 2001
Neutrophils Diegelmann RF Wound Repair Regen Vol 11 2003 Hartl, D Cleavage of CXCR1 on neutrophils disables bacterial killing in cystic fibrosis lung disease Nature Medicine Vol 13, 2007 Biofilms and Chronic Wound Inflammation JWC Vol 17, 2008
Host Defenses Leid, JG Infect Immun Vol 70, 2002
Current Antimicrobial Wound Solutions are Ineffective Against Microbial Biofilms - in-vitro testing against biofilms 1 CDC Reactor Biofilm Model, 72 hour biofilm, 15 8 Log 10 Viable Bacteria (cfu/mL) minute treatment 6 4 2 0 S. aureus P. aeruginosa 1: Johani, K., et al. "Evaluation of short exposure times of antimicrobial wound solutions against microbial biofilms: from in vitro to in vivo." Journal of Antimicrobial Chemotherapy (2017). *: Chlorhexidine: 0.015% chlorhexidine + 0.15% cetrimide **: 10% povidone-iodine
Current Antimicrobial Wound Solutions are Ineffective Against Microbial Biofilms – ex-vivo testing against biofilms on porcine skin explants 1 Treatment of Porcine Explants, 10 8 cfu of P . aeruginosa inoculation, 3 days growth before or after 12 cycles of 10 min installation 10 Viable Bacteria (cfu/mL) 8 6 4 2 0 Total Bacteria Biofilm NPWT Saline Microcyn Installatoin Installation 1: Johani, K., et al. "Evaluation of short exposure times of antimicrobial wound solutions against microbial biofilms: from in vitro to in vivo." Journal of Antimicrobial Chemotherapy (2017).
Current Antimicrobial Wound Solutions are Ineffective Against Microbial Biofilms – in-vivo testing of chronic wounds and Key Findings 1 • Key Findings – The performance of these solutions is poor when challenged against mature biofilms using short exposure times that mimic real clinical use (i.e. 15 min application) – Clinicians using topical antimicrobials to cleanse chronic wounds as a single therapy under the assumption of removing biofilm may therefore experience poor clinical outcomes – Clinicians should consider Effects of Melaleuca Oil pre- and post- multifaceted strategies that include treatment of 10 chronic non-healing sharp debridement as the gold diabetic foot ulcers. Box-and-whisker plots standard show the median log<sub>10</sub> 16S copies/mg of tissue values for all 10 patients 1: Johani, K., et al. "Evaluation of short exposure times of antimicrobial wound solutions against microbial biofilms: from in vitro to in vivo." Journal of Antimicrobial Chemotherapy (2017).
Slow Penetration
Biochemical Impairment of Chronic Wounds Elevated proinflammatory cytokines Elevated proteinase activity – MMPs Diminished activity of growth factors Degraded receptor sites (degradation blocked by the addition of MMP inhibitors)
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