Leishmaniasis is an infrequent protozoal disease in dogs caused by Leishmania spp. Leishmaniasis in dogs is a significant zoonotic disease transmitted to human beings from the affected dogs. Sandfly vectors transmit the organism. The rodents and dogs are the primary reserves of the organism, and the cat is an incidental host.
Etiology of Leishmaniasis in Dogs
There are two forms of Leishmaniasis; cutaneous Leishmaniasis and visceral Leishmaniasis. Cutaneous Leishmaniasis is caused by Leishmania tropica and mainly causes oral lesions. Visceral Leishmaniasis is caused by Leishmania donovani, which mainly causes anemia. The organism is transmitted by Phlebotomus spp of sandflies. When there is an incidence of human Leishmaniasis, the is considered as the carrier.
Clinical Signs of Leishmaniasis
- The disease is characterized by one or more cutaneous ulcers.
- The ulcers may be dry or wet crater-like sores covered with thick brown scabs.
- The edge of the lesion is usually erythematous and hairless, and these lesions are itchy.
- They usually heal spontaneously within one month to a year, leaving a permanent scar.
- Dogs invariably develop cutaneous lesions. Initially, hyperkeratosis, depigmentation of the muzzle and footpads, scaling of the nose, around the eyes, ears, and even diffuse alopecia are prominent signs.
- Muscle atrophy and weight loss, and ocular discharge are common.
- Visceral Leishmaniasis is a chronic disease, but several acute fatal cases have been recorded.
- The incubation period is usually several months.
- Anemia, emaciation, and general debility are common.
- Skin scruffiness, extensive alopecia, and eczema are also common.
Diagnosis of Leishmaniasis in Dogs
The disease can be diagnosed by the following means:
- The characteristics of clinical signs.
- Skin ulcers are refractory to conventional wound treatment is diagnostic.
- The organisms occur in large numbers in the tissue macrophase at the borders of skin ulcers and in macrophages of lymph nodes, spleen, and liver.
- Bacterial culture of aspiration material.
- Serology of positive titers.
Differential Diagnosis of Canine Leishmaniasis
Leishmaniasis is confused with the following diseases or conditions:
Treatment and Prevention of Leishmaniasis in Dogs
The treatment strategies for canine leishmaniosis are as follows:
- Organic antimony compounds are used for the treatment of cutaneous Leishmaniasis. Magnesium antimony @100 mg /kg or Sodium Stibogluconate @ 50 mg/kg IV or SC daily for four weeks.
- Allopurinol @ 15 mg/kg per oral (PO) twice a day for eight weeks in dogs is also effective.
- Treatment of Canine Visceral Leishmaniasis is complex, and many cases are refractory to treatment.
- Insecticidal spray and repellents are used for the elimination of sandflies.
Concluding Words on Canine Leishmaniasis
Leishmaniasis is a significant zoonotic disease that transmits from dogs to human beings. The disease is sometimes dormant in dogs but critical for humans. The organism transmits via Sandflies from reservoir host dogs to humans. The disease can be prevented by reducing the population of sandflies.