Tongue nodules in canine leishmaniosis — a case report

Abstract

BackgroundCanine leishmaniosis (CanL) caused by Leishmania infantum is an endemic zoonosis in southern European countries. Infected dogs can present rare or atypical forms of the disease and diagnosis can be challenging. The present report describes a case of tongue nodules in a 3-year-old neutered female Labrador Retriever dog with leishmaniosis.FindingsA fine needle aspiration of the lingual nodules revealed amastigote forms of Leishmania inside macrophages. Differential diagnosis ruled out neoplasia, calcinosis circumscripta, solar glossitis, vasculitis, amyloidosis, eosinophilic granulomas, chemical and electrical burns, uremic glossitis and autoimmune diseases. Combined therapy with antimoniate meglumine and allopurinol for 30 days resulted in the normalization of hematological and biochemical parameters. Two months after diagnosis and the beginning of treatment, a mild inflammatory infiltrate was observed by histopathology, but an anti-Leishmania immunofluorescence antibody test (IFAT) was negative as well as a PCR on both tongue lesions and a bone marrow aspirate. Seven months after diagnosis, the dog’s general condition appeared good, there were no tongue lesions and a new IFAT was negative. Fifteen months after diagnosis this clinically favourable outcome continued.ConclusionsThe dog could have suffered a relapsing episode of CanL, but a new systemic or local infection cannot be excluded. Regular clinical re-evaluation should be maintained, as a future relapse can potentially occur. In conclusion, CanL should be considered in the differential diagnosis of nodular glossitis in dogs.

Nodular granulomatous glossitis as the sole clinical sign in canine leishmaniosis

“…An important diagnostic finding pertaining to the canine leishmaniosis‐associated lingual lesions in all the published cases, including the present dog, was the cytologic and histopathologic/immunohistologic evidence of Leishmania spp. amastigotes and the presence of a granulomatous inflammation, ruling out other potential differential diagnoses including neoplastic disease and eosinophilic granuloma …”

Laboratory tests for diagnosing and monitoring canine leishmaniasis

“…The interpretation of clinicopathologic, serologic, and molecular tests should take into account the history (eg, exposure to phlebotomine vectors), signalment (male dogs > 2 years are at high risk), and clinical presentation. The latter is characterized by a wide spectrum of clinical presentations, ranging from infections characterized by the absence of overt clinical findings in the presence of obvious laboratory abnormalities, to more or less marked clinical and laboratory abnormalities that may require hospitalization, especially in cases with severe life‐threatening complications …”

Pathologic Mechanisms Underlying the Clinical Findings in Canine Leishmaniosis due to Leishmaniainfantum/chagasi

“…These lesions have been attributed to the migration of infected macrophages to sites of microtrauma in the oral mucosa or to accidental chewing on infected sandflies. 49,75,108,149 Digestive disease in CanL is an uncommon to rare cause to admit leishmanial dogs and is mainly expressed as chronic hepatitis or chronic colitis, the subclinical form of which far outnumbers the clinical one. 3,46,120 In the liver, chronic granulomatous inflammation may involve the sinusoids, portal area, or capsule or become diffuse along with the presence of parasites that may also be seen within Kupffer cells and hepatocytes.…”