Infectious Disease Medicine: Always Something New

Transcription

1 Infectious Disease Medicine: Always Something New John M. Townes, MD Associate Professor of Medicine Division of Infectious Diseases Oregon Health & Science University

2 Context: Always something new Epidemics Emerging pathogens Drug resistance and new antibiotics Medical equipment/procedures Diagnostic tests Guidelines and definitions Politics and policies Healthcare economics Fundamentals of ID Practice 1. Ensure focus is on the right question 2. Expand differential diagnosis 3. Assist with choice of empiric therapy 4. Confirm diagnosis and tailor definitive therapy (stewardship) 5. Monitor for adverse events during therapy 6. Prevent transmission

3 A consult call 54 year old injection drug user Back pain, fever, cough History of Hep C, chronic back pain, drug seeking T 101.5, P 102, BP 90/60, RR 24, 02 Sat 91% Confused, lungs sound junky WBC 15K, Platelets 90K, Hematocrit 33, Creatinine 1.7, tox screen + I think he s intoxicated and has community acquired pneumonia. What oral antibiotic should I give? Fundamental # 1: Focus on the right question

4 Listen carefully 54 year old injection drug user Back pain, fever, cough History of Hep C, chronic back pain, drug seeking T 101.5, P 102, BP 90/60, RR 24, 02 Sat 91% Confused, lungs sound junky WBC 15K, Plt 90K, Hct 33, Cr 1.7 What is the most likely cause of his sepsis? Sepsis re defined: Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis 3) JAMA. 2016, 315 (8): Sepsis is: Life threatening organ dysfunction caused by a dysregulated host response to infection

5 Measuring organ dysfunction Sequential Organ Failure Assessment (SOFA) Score based on multiple measured clinical and laboratory values qsofa (Quick Sofa) Respiratory rate 22/min Altered mentation Systolic BP 100 mm Hg Any 2 of 3 in qsofa associated with poor outcome Surviving Sepsis Campaign Critical Care Medicine, March2017, 45(3) Obtain cultures before antibiotics Give empiric antibiotics within one hour* Cover all likely pathogens* Narrow antibiotic spectrum after ID and susceptibility are known *Warning: May not be feasible; adherence may lead to unnecessary antibiotic use!

6 Epidemic of drug use Fundamental # 2: Expand the differential diagnosis Injection drug user and a history of back pain presents with sepsis Possible sources of the sepsis syndrome might include: Acute drug toxicity (i.e. not sepsis) CAP (community acquired pneumonia) Blood stream infection (Bacteremia or fungemia) +/ complications: Abscess: Spinal epidural, Brain, Liver, Spleen, Kidney, Psoas muscle Endocarditis Spinal osteomyelitis and discitis Septic pulmonary emboli Septic arthritis Septic venous thrombosis

7 Fundamental #3: Guide empiric therapy (A lot to think about!) Medical history Co morbid conditions, devices, surgery, immune suppression, risk behaviors, receipt of antibiotics, location, prior colonization, allergies Current Clinical status Organ dysfunction Drug drug interactions Available IV access/route of administration Anatomic site of infection (e.g. CNS) Local epidemiology Local prevalence of pathogen Local antibiotic resistance patterns Fundamental # 4: Stewardship

8 Serious threats MDR Acinetobacter Drug resistant Campylobacter Fluconazole resistant Candida ESBLs VRE MDR Pseudomonas Resistant Salmonella Resistant S. Typhi Resistant Shigella MRSA Resistant S. Pneumoniae Resistant tuberculosis

9 Number of New Systemic Antibacterial Agents Approved by FDA since Number Approved Spellberg, Clin Infect Dis 2008;46: National Action Plan 2020 Goals Establish antibiotic stewardship programs in all acute care hospitals Improve stewardship across healthcare settings 50% reduction in inappropriate outpatient antibiotic use 20% reduction in inappropriate inpatient antibiotic use Establish State antibiotic resistance monitoring programs in all states Eliminate use of antibiotics for growth promotion in food animals Require veterinary oversight of medically important antibiotics in feed

10 The Joint Commission Proposed Standard for Antimicrobial Stewardship Applies to across spectrum of care Ambulatory Care, Critical Access Hospital, Hospital, Nursing Care Center, Office Based Surgery Leaders establish ASP as an organizational priority Educate staff and licensed independent practitioners about antimicrobial resistance and ASP practices Education occurs upon hire and annually thereafter ASP = Antimicrobial Stewardship Program. Accessed on February 18, IDSA Guidelines for Implementing an Antibiotic Stewardship Program Published in Clin Infect Dis 2016;62:e51 e77.

11 Gram stain: Gram positive cocci in clusters Rapid molecular diagnostic test identifies MRSA within a few hours Valve replaced. Bacterial vegetation on heart valve Dx= Endocarditis Endocarditis guidelines Published in Circulation. 2015; 132:

12 S.aureus Bacteremia: Benefit of ID Consultation 154 patients with S.aureus bacteremia (SAB) ; 25% had no ID Consult Management more consistent with guidelines in ID consult group Mortality less in those with ID consult: 5% vs 23% (P=0.001) Conclusion: Data support requiring automatic ID consult for SAB Buehrle, AJIC 2017 Fundamental # 5 Monitor for adverse events through therapy

13 OPAT OPAT The ID Physician Role Leader of multi disciplinary team Referring or primary physician, specialist nurse, pharmacist, case manager Establish written policies and procedures Ensure good communication and collaborative decision making Patient selection Type of access Site of care (home, SNF, infusion center) Determine appropriate antibiotic, dose, and duration Provide frequent follow up visits and therapeutic monitoring

14 ID Consult Case, page 2 After valve replacement, patient complains of worsening back pain History of chronic pain noted, narcotics increased New onset urinary retention, blamed on narcotics New onset of numbness and weakness in lower extremities ID consultant called back Recommends MRI lumbar spine Epidural Abscess

15 Assessment of malpractice claims, epidural abscess 56 cases from a legal claims database 30% resulted in plaintiff rulings Mean award : $5,277,468 (Range $185,000 $19,792,000) 39% settled out of court Mean award for settled out of court cases: $1,914,265 (100,000 $4,500,000) Paraplegia, quadriplegia, diagnostic or treatment delay were associated with plaintiff verdict Internists, not surgeons, were most likely to be sued Fundamental # 6: Prevent Transmission

16 SHEA MRSA Guidelines, 2003 Active surveillance cultures to identify reservoir of spread Gloves, gown, and mask on entering room of colonized or infected patient Hand hygiene campaign Antibiotic stewardship Decolonization in selected circumstances Implemented in entire VA system Many Institutions Abandoning Isolation for MRSA VCU UMASS Detroit MC Tufts NEMC St. Johns MC, Santa Monica Univ Rochester MC Baylor St. Luke s MC UCLA Univ Nebraska MC San Francisco General Hosp Univ San Francisco MC Alta Bates MC, Oakland Univ Cincinnati MC Oakwood Hospital System, MI Baystate Hospitals Dartmouth MC Cleveland Clinic

17 Case, Page 3 two years later Fatigue, short of breath, intermittent night sweats and weight loss Exam: Enlarged liver and spleen, new heart murmur Labs: Low white blood cell count, low platelet count and anemia, elevated creatinine Echocardiogram shows new mitral regurgitation, concern for prosthetic valve endocarditis Routine blood cultures are negative No response to broad spectrum antibiotics for 6 weeks What s going on? ID consultant suggests collecting special blood cultures for Mycobacteria After 4 weeks, blood cultures yield Mycobacterium chimaera M.chimaera Outbreak Outbreak investigation in Zurich, Switzerland: 2006 to male patients (49 64 years of age) Prosthetic valve endocarditis or vascular graft infection due to M. chimaera, a slow growing environmental organism Infections noted as late as 4 years following cardiac surgeries Mortality in these cases was ~50% Positive cultures from water circuits of heater cooler units and the air samples when the units were in use within the operating suite

18 Summary ID physicians work in a rapidly changing context Fundamentals of practice stay the same Emerging pathogens, epidemics, technologies, and policies affect thought process and roles within healthcare ID physicians increasingly in demand Clinical consultations, including phone and e consult Antibiotic stewardship OPAT team management Healthcare epidemiology and infection control