Anaplasma phagocytophilum (Formerly Ehrlichia phagocytophila - Human Anaplasmosis (Human granulocytic anaplasmosis, Tick-borne fever; Pasture fever) - Microscopic exam; Molecular diagnosis (PCR).

Anaplasma phagocytophilum - Human anaplasmosis (Human granulocytic anaplasmosis, tick-borne fever; Pasture fever) - Molecular diagnosis (PCR).  

Anaplasma phagocytophilum (formerly Ehrlichia phagocytophilum) is a small, intracellular must gram - negative bacteria lacking lipopolysaccharide (United Bacterium; phylum Proteobacteria; Class Alphaproteobacteria; Order Rickettsial; Family Ehrlichiaceae; Gender Anaplasma), with tropism by neutrophils that invade, causing anaplasmosis in sheep and cattle, also known as tick - borne fever and fever pasture. In people cause a zoonotic disease called human granulocytic anaplasmosis.

This disease is transmitted by ticks and infects granulocytic neutrophil myeloid series, initially localized in an endosome, where it divides by binary fission, growing in groups called morulae.

Although this disease is known as pathogenic animals since 1932, the human granulocytic anaplasmosis was first described in 1990 in a febrile patient in Wisconsin (USA), who had been bitten two weeks earlier by a tick. Other symptoms include headaches, absence of rash, leucopenia, thrombocytopenia and moderate hepatic impairment. Since its incidence has increased and has been found in Europe.  

Diagnostic methods

You can use three methods:

  • Microscopic observation to visualize intracellular inclusions in neutrophilic leukocytes in blood smears stained with Giemsa o Wright. This method has the drawback of low sensitivity due to the difficulty of observing the infected neutrophilic leukocytes.
  • Antibody detection using a sample of acute phase and convalescent phase sample (2 weeks later), by indirect immunofluorescence methods. This method has the disadvantage that it requires waiting for the infection is induced specific antibodies, so is not useful for application in the acute phase of the disease.
  • DNA molecular detection of A. phagocytophilum by PCR testing. This method has the advantage that it can be applied at any stage of the disease, while this persists.  

Tests in IVAMI  

  • Molecular DNA detection test A. phagocytophilum by double PCR.  

Recommended sample:

 

  • Uncoagulated blood extracted with EDTA.

Preservation and shipment of sample:

 

  • Refrigerated (preferred) for less than 2 days.

Cost of the test: