LeishVet guidelines for the practical management of canine leishmaniosis

Abstract

The LeishVet group has formed recommendations designed primarily to help the veterinary clinician in the management of canine leishmaniosis. The complexity of this zoonotic infection and the wide range of its clinical manifestations, from inapparent infection to severe disease, make the management of canine leishmaniosis challenging. The recommendations were constructed by combining a comprehensive review of evidence-based studies, extensive clinical experience and critical consensus opinion discussions. The guidelines presented here in a short version with graphical topic displays suggest standardized and rational approaches to the diagnosis, treatment, follow-up, control and prevention of canine leishmaniosis. A staging system that divides the disease into four stages is aimed at assisting the clinician in determining the appropriate therapy, forecasting prognosis, and implementing follow-up steps required for the management of the leishmaniosis patient.

Figure 1

The life cycle of L. infantum with indication of proven and unproven non-sandfly routes of transmission to dogs.

Figure 2

Algorithm describing the selection of blood donors and exclusion of infected dogs. Any dog infected will be excluded.

Figure 3

The distribution of canine L. infantum infection in Europe.

Figure 4

Clinical manifestations and immunological characteristics of L. infantum infection in dogs.

Figure 5

Different patterns of cutaneous lesions in CanL: A) Exfoliative periocular alopecia and blepharitis; B) Ulcerative nasal mucocutaneous lesions; C) Papular dermatitis in the inguinal region; D) Nodular crateriform lesions bordering the muzzle; E) Ulcerative erythematous lesions on the plantar surface of the paw and between pads; F) Onychogryphosis.

Figure 6

Some clinical signs found in CanL: A) Epistaxis; B) Bilateral uveitis and corneal opacity; C) Purulent conjunctivitis and blepharitis; D) Exfoliative alopecia in the rear leg and popliteal lymphadenomegaly; E) Marked cachexia and generalized exfoliative alopecia.

Figure 7

Interpretation of cytology A) Interpretation of cytology requires time and expertise for the detection of Leishmania amastigotes when parasites are in low numbers and freed from the cells. Note the nucleus (N) and the kinetoplast (K) of extracellular amastigotes (arrows) in a fine needle aspirate of a reactive lymph node from a dog with clinical leishmaniosis (x100, Diff-quick stain); B) High numbers of intracellular and extracellular Leishmania amastigotes in a fine needle aspirate of a reactive lymph node from a dog with clinical leishmaniosis (x100, modified Giemsa stain).

Figure 8

The different purposes of CanL diagnosis.

Figure 9

Definition of L. infantum-infected but healthy versus sick dogs. Dogs with clinical leishmaniosis are defined as those presenting clinical signs and/or clinicopathological abnormalities and having a confirmed L. infantum infection. Dogs with subclinical infection, or clinically healthy but infected dogs, are defined as those that present neither clinical signs on physical examination nor clinicopathological abnormalities by routine laboratory tests (CBC, biochemical profile and urinalysis) but have a confirmed L. infantum infection.

Figure 10

The most common diagnostic methods for CanL.

Figure 11

Interpretation of serological qualitative rapid tests for CanL.

Figure 12

Selection of tissues to be used for PCR and types of PCR techniques when suspecting CanL.

Figure 13

Flow chart for the diagnostic approach to dogs with suspected clinical signs and/or clinicopathological abnormalities consistent with CanL.

Figure 14

Management of Leishmania-seropositive but clinically healthy dogs and PCR-positive but seronegative dogs. Clinically healthy but seropositive dogs would normally present with low antibody titers and should be confirmed by retesting. Confirmed seropositive dogs should be monitored with physical examinations, routine laboratory tests and serological tests on a regular basis every 3-6 months to assess the progression of infection towards disease.