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Links Between Testing and Reporting from the Laboratory Perspective Jyotsna Shah, Ph.D, CMLD, MBA February 25, 2004. IGeneX Reference Laboratory. Specializes in Diagnosis of Lyme and Other Tick Borne Diseases. Other Tick-borne Diseases Associated With Lyme Disease. Ehrlichiosis
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Links Between Testing and Reporting from the Laboratory Perspective Jyotsna Shah, Ph.D, CMLD, MBA February 25, 2004
IGeneX Reference Laboratory Specializes in Diagnosis of Lyme and Other Tick Borne Diseases
Other Tick-borne Diseases Associated With Lyme Disease • Ehrlichiosis • Human Granulocytic (HGE) • Human Monocytic (HME) • Babesiosis • B. wa-1 • B. microti? • Bartonella • B. henselae
Lyme Disease Testing Indirect Tests: Detection of Patient’sImmune responses to Borrelia burgdorferi, causative agent of Lyme Disease. Serology (C6), Western blots, Immunofluorescence Direct Tests:Detection of the Borrelia burgdorferi specific proteins (antigens), DNA and RNA, in patient clinical specimen (blood, serum, urine, CSF, etc.) Lyme Urine Antigen, PCR, Reverse Western blot
Lyme Disease CaseClassification by CDC CONFIRMED CASE A Case with EM, or A Case of Late Manifestation that is Laboratory Confirmed. Laboratory Confirmation Isolation of Borrelia burgdorferi from a clinical sample or Demonstration of IgM or IgG antibodies to B. burgdorferii in serum or CSF. A two-test approach using a sensitive ELISA or IFA, followed by Western Blots. NOTE: The above is a SURVEILLANCE case definition, developed for national reporting of Lyme Disease by CDC. IT IS NOT INTENDED FOR USE IN CLINICAL DIAGNOSIS. Ref: MMWR 46:RR10
IgG WESTERN BLOT • IGeneX Reference Laboratory • 23-25 kDa (Osp C) • 31 kDa (Osp A) • 34 kDa (Osp B) • 39 kDa • 41 kDa (Flagella) • 93 kDa (83 kDa?) • CDC/ASPHLD • 18 kDa • 23-25 kDa (Osp C) • 28, 30 kDa • 39 kDa • 41 kDa (Flagella) • 45, 58, and 66 kDa • 93 kDa
IgM WESTERN BLOT • IGeneX Reference Laboratory • 23-25 kDa (Osp C) • 31 kDa (Osp A) • 34 kDa (Osp B) • 39 kDa • 41 kDa (Flagella) • CDC/ASPHLD • 23-25 kDa (Osp C) • 39 kDa • 41 kDa (Flagella)
In fact, studies conducted by the group responsible for Lyme Disease proficiency testing for the College of American Pathologists (CAP) concluded that the currently available ELISA assays for Lyme Disease do not have adequate sensitivity to be part of the two-tiered approach of the CDC/ASHLD, whereby only ElISA-positive samples can be tested by Western blotting. REFERENCE Bakker LL, Callister SM, Wantol PG and Shell RF. Interlaboratory comparison of test results of detecting Lyme disease by 516 participants in the Wisconsin State Laboratory of hygiene College of American Pathologists proficiency testing Program.J. Clin Microbiol. 1997 537-543. ILADS
Engstrom SM, E. Shoop, and R. Johnson. 1995. Immunoblot Interpretation for Serodiagnosis of Early Lyme Dis. J. Clin. Micro. 33:419-427. • 55 patients with EM • Blood Collected on 5 visits over 4 months • Patients were positive on one or more visits • 20% of patients remained seronegative • In control group that might resemble Lyme IgM and IgG, WB specificities were 93-94% • 2/5 IgG bands (20, 23-25, 35, 39, 93) scored In fact, studies conducted by the group responsible for Lyme Disease proficiency testing for the College of American Pathologists (CAP) concluded that the currently available ELISA assays for Lyme Disease do not have adequate sensitivity to be part of the two-tiered approach of the CDC/ASHLD, whereby only ElISA-positive samples can be tested by Western blotting.
Presence of Nucleic Acid As Confirmed Diagnosis • For the diseases listed below, CDC considers, the presence of infectious agent’s Nucleic Acid in a clinical sample, acceptable as confirmed diagnosis of the disease. (MMWR 46:RR-10) • Bacteria (Nucleic Acid Amplification)Chlamydia • Gonorrhea • Pertussis • Viruses • Hantavirus Pulmonary Syndrome (PCR) • Arboviral Encephalitis (Genomic Sequences) • Why Not For LYME DISEASE?
HGE = Human Granulocytic Ehrlichia; HME = Human Monocytic Ehrlichia Titer of >1:160 is considered positive