Microbial Hide-and-Seek: Laboratory Results Revealed

1. Microbial Hide-and-Seek:Laboratory Results Revealed Sara J. Blosser, Ph.D., D(ABMM) Director, Division of Clinical Microbiology Indiana State Department of Health sblosser@isdh.in.gov 317-921-5894

2. What is the Role of the Microbiology Laboratory? • Clarify the presence of infection. Clinical presentation must guide the microbiological workup and all results must be interpreted clinically! • Specify the etiology of infection. • Motivate the appropriate selection of antimicrobial agents • Assist in identification, control, and prevention of nosocomial or public health infections

3. Microbiology Pearl #1 A test is only is as good as the specimen submitted.

4. Microbiology Pearl #2 Specimen source dictates workup. [Not all organisms that grow in culture will be fully identified by the microbiology laboratory.]

5. Microbiology Pearl #3 Be specific about the body site and type of wounds or fluids when submitting specimens – this can help guide workup and test interpretation.

6. Microbiology Pearl #4 “A strong, ongoing partnership between microbiology laboratory professionals and infection preventionists should remain a top priority in all infection prevention programs to ensure maximum patient safety and positive patient outcomes.” - The Infection Preventionist’s Guide to the Lab

7. Case - • Unattended death. On autopsy, pus observed when skull cap removed – suggestive of Meningococcal Meningitis. • Coroner did not perform Gram stain • Several days later, Micro lab asked to perform Gram stain after Epi/IP consult. • Gram stain read: Few GNDCs, some intracellular.

8. Case, continued… • Micro Lab does not routinely perform autopsy cultures, so they reported the Gram stain and placed the specimen back in the fridge. • A few days later, IP/Epi wants to know what is growing! • No special instructions were provided to see if the Micro Lab could perform culture – this is an atypical request – enhanced communication can help with atypical cases! • A strong, ongoing relationship between IP/Lab never hurts … and can often help!

9. Some good references to help interpret microbiology reports

11. CLSI M100-S27

12. CLSI M100-S27

13. phil.cdc.gov; selectagents.gov

14. IN CASE OF EMERGENCY THE MICRO LAB Call

15. Case 2 • Indiana hospital pharmacist is asked to consult on antibiotic selection for a post-operative ‘antibiotic cement’. • Patient is a 22-year-old Libyan male • Dx: Chronic osteomyelitis of the L tibia • Has recently noticed increased drainage from LLE wound • CT demonstrates fluid collection • Pt is admitted and undergoes surgery for hardware replacement

16. Microbiology Surgical Wound and Bone cultures performed. Culture results: 2+ Klebsiella pneumoniae

17. Carbapenem Resistant Enterobacteriaceae (CRE) NDM, VIM, IMP KPC Combination of AmpC, ESBL, porin mutations Non-carbapenemase Carbapenemase (serine-based) Carbapenemase (Zinc-catalyzed)

18. Isolate is susceptible to Aztreonam (monobactam) but resistant to all other tested β-lactam antibiotics Suggestive of MBL (metallo β-lactamase)

19. Woerther et al., 2013. Clin Microbiol Rev 26(4):744-58; phil.cdc.gov

20. Patient has a history of international travel, including invasive medical procedures. Potential for uncommon or rare resistance determinants.

21. ISDH Algorithm Day 1 – Receive isolate and subculture Day 2* – Confirm ID and Perform PCR • MALDI-TOF MS • Multiplex PCR [KPC, NDM-1, OXA-48, IMP, VIM] If Positive, report Finalized result. • Ex. Klebsiella pneumoniae, KPC positive If Negative – report Preliminary Negative. Day 3 – CarbaNP on PCR negative specimens If Positive, send to CDC for further testing. If Negative, report out as Negative.

22. ISDH Algorithm ISDH Results: Positive for NDM-1 (New Delhi Metallo-β-lactamase) Day 1 – Receive isolate and subculture Day 2* – Confirm ID and Perform PCR • MALDI-TOF MS • Multiplex PCR [KPC, NDM-1, OXA-48, IMP, VIM] If Positive, report Finalized result. • Ex. Klebsiella pneumoniae, KPC positive If Negative – report Preliminary Negative. Day 3 – CarbaNP on PCR negative specimens If Positive, send to CDC for further testing. If Negative, report out as Negative.

24. MBLs – Impact on Clinical Care • MBLs tend to be pan-resistant to β-lactam antibiotics, but susceptible to aztreonam. • New drugs like ceftazidime-avibactam, although effective against KPC-producing organisms, do not have activity against MBLs. • Many MBL-producing organisms also exhibit resistance to fluoroquinolones, aminoglycosides, and folate pathway inhibitors.

25. What happened next? • Patient was immediately put on contact precautions. • ID was consulted: • Diagnosis made antibiotic management complex. • The state (ISDH) was notified. • Patient was discharged on minocycline, ciprofloxacin, and amoxicillin. • Follow up was scheduled. https://www.cdc.gov/hai/organisms/cre/cre-toolkit/index.html

26. In Indiana, CP-CRE is reportable for both isolates and condition. • CDR Modification Highlights Actionable Interventions • Sets a timeline (72 hours) for investigation • Prevent spread by encouraging: • Contact precautions • CDC CRE Toolkit Use • Screening for colonization • Chlorhexidine bathing

27. Indiana saw four (4) cases of NDM-1 in 2016. https://www.cdc.gov/hai/organisms/cre/trackingcre.html

28. Odds of a patient with CP-CRE bacteremia dying within 14-days: 4x times higher • Higher rates of bacteremia recurrence • More likely to receive combination antibiotic therapy • Antibiotics given for a longer duration CID, 2017; 64(3):257-64

29. CP-CRE in Action Hospital IP & Epidemiology Hospital IP LAB

30. When to call the laboratory…

31. … Gram Stains

32. … Culture Results

33. …. Ordered Tests

34. …Whenever you think you’re seeing something weird, strange, or unusual.

35. …Whenever you want to request a test that is weird, strange, or unusual.

36. WHEN IN DOUBT…. THE MICRO LAB Call

37. Thank you Sara J. Blosser, Ph.D. Director, Division of Clinical Microbiology Indiana State Department of Health sblosser@isdh.in.gov 317-921-5894

38. Save the Date! ISDH Lab Trainings…