Interpretation of Lyme and Quantiferon Tests

1. Interpretation of Lyme and Quantiferon Tests Thomas M File, Jr MD MSc MACP FIDSA FCCP Chair, Infectious Disease Division Summa Health System Akron, Ohio; Professor of Internal Medicine, Chair ID Section Northeast Ohio Medical University Rootstown, O

2. Lyme-stages • Early (days to weeks after tick bite; minority recall) • Erythema migrans (80%), fatigue, malaise , HA, myalgia, arthralgia, regional lymphadenopathy • Early disseminated: (weeks to months) • Musculoskelatal; neuro 15% (lymph meningitis, cranial neruropathy); carditis 1% • Late (months to years) • MS 60%; Neurologic

3. Early Lyme Characteristic Rash Reaction as bacteria move through body; not multiple bites Photo: T File MD

4. Lyme-Diagnosis • Early-clinical with rash; serology little value • Serology • 2 tiered: ELISA (10% false +) then Western Blot • VisE C6 ELISA • Measures AB to major protein sequence • More accurate, also good for European strains • Antibodies may persist for years after Lyme disease has been treated and cured • PCR

5. LYME: WESTERN BLOT

6. Criteria for Western Blot for Lyme

7. Lyme-Diagnosis ?? • Patient with Erythema Migrans ELISA negative 2. Patient with chronic fatigue ELISA Positive; Western Blot IgG and IgM + band 41* (+ ANA) • Patient with knee swelling X 2 weeks ELISA Positive; Western Blot: IgM no bands; IgG + 18,23,28,30,39,41,45,58,66,93 • Patient referred for “ Lyme test” ELISA 1.13 (reference < 0.91); Western Blot: IgM Neg.; IgG + 41 * Common cross reactions * Common cross reaction

8. Lyme-Diagnosis ?? 5. 37 y/o female with 4 months of neurologic symptoms and fatigue ELISA positive; Western Blot-IgM neg.; IGG-5 + bands 6. 41 y/o female with burning of feet ELISA low +; Western Blot- IgM + one band; IgG-+ 2 bands • 38 y/o female with headaches ELISA +; Wesern Blot IgM neg.; IgG +1 band 8. 57 y/o malePatient with knee swelling X 2 weeks ELISA +; Western Blot: IgM +1 band; IgG +10 bands * Common cross reactions

9. Southern Tick Associated Rash Illness ( STARI) • B. lonestari; A. americanum feed on white-tailed deer. • Mild illness with onset of skin lesions • Doxy 100 mg BD or Amox 500 mg TD X 10 days.

10. Transmission of M. tuberculosis • M. tb spread via airborneparticles called dropletnuclei • Expelled when person withinfectious TB coughs, sneezes, shouts, or sings • Transmission occurs when droplet nuclei inhaled and reach the alveoli of the lungs, via nasal passages, respiratory tract, and bronchi

11. Pathogenesis

12. Pathogenesis

13. Pathogenesis

14. Latent TB Infection (LTBI) • Granulomas may persist (LTBI), or may break down to produce TB disease • 2 to 8 weeks after infection, LTBI can be detected via TST or interferon-gamma release assay (IGRA) • The immune system is usually able to stop the multiplication of bacilli • Persons with LTBI are not infectious and do not spread organisms to others

15. TB Classification System

16. Latent TB infection vs TB Disease

17. Latent TB (Quantiferon) • Less subjectively than Skin Test • No affect of BCG; but may have cross reactivity with M. kansaii, marinum or szulgari • Interpretation of Quantiferon test

18. General Recommendations for Using IGRAs • Preferred when testing persons • Who might not return for TST reading • Who have received BCG vaccination • Immune suppressed • Generally should not be used to test children <5 years of age, unless used in conjunction with TST

19. Interpret Quantiferon tests (CXR neg.)

20. Interpret Quantiferon tests (CXR neg.)