DIAGNOSIS

Diagnosis is based on clinical signs and/or clinicopathological abnormalities compatible with disease and by confirmation of Leishmania infantum infection, using mainly serological and molecular techniques.

Main purposes for the diagnosis of L. infantum infection:

A. Confirm the disease in a dog with clinical signs and/or clinicopathological abnormalities consistent with CanL.

B. Screening clinically healthy dogs living in or travelling to or from endemic areas:

  • blood donors
  • breeding dogs
  • dogs prior to leishmaniosis vaccination
  • imported dogs
 
DIAGNOSTIC APPROACH OF CANINE LEISHMANIOSIS

Flow chart for the diagnostic approach to dogs not vaccinated against canine leishmaniosis (CanL) with suspected clinical signs and/or clinicopathological abnormalities consistent with CanL

Dog with clinical signs and/or clinicopathological abnormalities consistent with CanL (in non-vaccinated)
 
 
* Cytology could be performed at the same time in any lesional tissue or biological fluid.
 
Infected but healthy versus sick dogs
  • Dogs with clinical leishmaniosis are those presenting compatible clinical signs and/or clinicopathological abnormalities, and having a confirmed L. infantum infection.
  • Dogs with subclinical infection (infected but clinically healthy) are those that present neither clinical signs on physical examination nor clinicopathological abnormalities on routine laboratory tests (CBC, biochemical profile and urinalysis) but have a confirmed L. infantum infection.
 
Diagnostic methods
  • Parasitological: cytology/histology, immunohistochemistry and culture.
  • Molecular: conventional, nested and real-time polymerase chain reaction (PCR).
  • Serological: quantitative (IFAT and ELISA) and qualitative (rapid tests).
 
What samples and techniques should be used for PCR?
  • First choice samples: bone marrow, lymph node, spleen, skin and conjunctival swabs.
    Less sensitive samples: blood, buffy coat and urine.
  • Most sensitive technique: real-time PCR.