The PCR-based diagnostic assays for detection of Ehrlichia from blood are highly specific to Analplasma phagocytophilum (HGA) and Ehrlichia chaffeensis (HME ) DNAs. The combination of the following three steps imparts a very high specificity and sensitivity to the test.

  • Hybridization/Selection
  • Amplification of Ehrlichia-specific DNA
  • Detection of Ehrlichia-specific amplified DNA fragments

Result Interpretation

Reference Range

  • Ehrlichia chaffeensis (HME): 
    • Negative, E. chaffeensis specific DNA not detected.
  • Anaplasma phagocytophilum (HGA):  
    • Negative, A. phagocytophilum specific DNA not detected.

Clinical Significance

The Ehrlichia chaffeensis (HME) PCR Test detects E. chaffeensis rDNA fragments in patient samples. The A. phagocytophilum (HGA) PCR Test detects A. phagocytophilum rDNA fragments in patient samples. The Ehrlichia or Anaplasma rDNA fragments are hybrid selected by probes, followed by PCR amplification of the selected fragments using specific primers.  PCR products are then confirmed with E. chaffeensis and A. phagocytophilum specific probes by Southern Blot Assay.


  1. Results should be interpreted in conjunction with other laboratory and clinical findings.
  2. Test results can only help the physician in confirming clinical diagnosis.

Ordering Information

  • Specimen: Whole Blood - minimum volume 0.5 ml
  • Container: EDTA whole blood tube
  • Collection and Shipping Instructions: See Serum and Whole Blood Samples- Collection & Shipping Instructions [THIS WILL LINK TO THAT PAGE]

Test Offered

Test# 770 HME (Monocyctic) PCR – Whole Blood CPT Code 87797, 87798
Test# 775 HME (Anaplasma phagocytophilum) PCR – Whole Blood CPT Code 87797, 87798
HME (Monocytic) PCR – Whole Blood and HGA (Anaplasma phagocytophilum) PCR – Whole Blood are part of the following Test Panels:
Test Panel# 2020 Complete Ehrlichia Panel

**Test/Panels are not yet available for New York Residents