Polyarthritis associated with visceral leishmaniasis in a juvenile dog

Canine visceral leishmaniasis (CL) is a zoonosis and a chronic systemic disease characterized by a wide spectrum of clinical signs, including, in rare occasions, polyarthritis. This report describes a case of CL in an 8-month old male boxer dog with a history of lameness, fever and lymphadenopathy. A definitive diagnosis of CL was based on the observation of the Leishmania amastigotes seen concomitantly, and for the first time, in the lymph nodes aspiration smears (in macrophages), synovial fluid (in macrophages and neutrophils) and blood (in neutrophils). Despite this extensive dissemination of the parasite, the animal was successfully treated with a multi-step combination of meglumine antimoniate, aminosidine and allopurinol.     

Placentitis associated with leishmaniasis in a dog

A 1.5-year-old Coonhound from Maryland aborted 7 fetuses. Placenta and internal tissues of 1 fetus were examined histologically. The predominant lesion was placentitis characterized by necrosis and infiltration of mixed leukocytes. Numerous Leishmania spp amastigotes were identified in placental trophoblasts, and the diagnosis was confirmed by use of immunohistochemical staining with Leishmania-specific antibodies. Protozoa were not found in the fetal tissues. An indirect fluorescent antibody test yielded a serum titer of 1:100, and a recombinant K39 immunoassay of serum yielded positive results for the K39 Leishmania antigen.     

Thrombosis and nephritic syndrome in a dog with visceral leishmaniasis

Visceral leishmaniasis with glomerulonephritis and nephrotic syndrome was diagnosed in a six-year-old dog presented with thromboembolic manifestations. A blood coagulation test indicated low levels of antithrombin III, prolonged partial thromboplastin time, hypofibrinogenaemia, an increase in fibrin degradation products and decreased plasminogenic activity. These results confirmed the diagnosis of thrombosis induced by glomerulonephritis, accompanied by secondary fibrinolysis. Bone marrow aspiration revealed an abundance of parasites of the genus Leishmania. Histopathology confirmed the presence of membranous glomerulonephritis due to Leishmania species parasites, as well as the presence of thrombosis in the aorta, iliac arteries, vena cava and femoral veni.     

Primary hypothyroidism associated with leishmaniasis in a dog

A case of primary hypothyroidism associated with leishmaniasis is described in a four-year-old, male Yorkshire terrier. Clinical diagnosis of hypothyroidism was confirmed by a low baseline serum tetraiodothyronine (T4), a reduced response to thyroid-stimulating hormone (TSH) stimulation, an increased serum TSH concentration, and scintigraphic thyroid gland examination. Examination of a thyroid biopsy showed many Leishmania amastigotes, both inside and outside of macrophages, together with signs of follicular atrophy.     

Acute paraplegia associated with vasculitis in a dog with leishmaniasis

A 14-month-old female crossbreed dog with leishmaniasis, receiving allopurinol, was presented with acute paraplegia. A diagnosis of renal failure with pelvic limb lower motor neuron signs was made and the dog was euthanased. Histopathological examination demonstrated leukocytoclastic vasculitis in multiple organs. Malacia and haemorrhage affecting the spinal cord was associated with multiple foci of vasculitis within the nervous tissue. Rupture and thrombosis of inflamed vessels caused haemorrhage in the spinal cord and subsequent paralysis.     

Subclinical leishmaniasis associated with infertility and chronic prostatitis in a dog

A stud dog was presented for acquired infertility. Haematospermia and teratozoospermia were found on two ejaculates 2 weeks apart. A presumptive diagnosis of prostatitis was made follo-wing ultrasound examination. An ultrasound-guided needle core biopsy was performed under general anaesthesia, revealing a mild chronic macrophagic and plasma cell prostatitis with intracytoplasmic amastigotes consistent with Leishmania spp. infection. Presence of Leishmania infantum, Leishmania donovani or Leishmania chagasi was confirmed by polymerase chain reaction in seminal plasma. Serology and serum protein electrophoresis confirmed the diagnosis of a subclinical active systemic leishmaniasis. A meglumine antimoniate and allopurinol treatment was given which clearly improved within 3 months both general condition and the quality of sperm. To the authors' knowledge, this is the first reported case of a prostatitis secondary to a Leishmania spp. infection. Subclinical systemic leishmaniasis should be considered in the differential diagnosis of infertility in dogs suffering from semen alterations.     

Monoclonal gammopathy associated with multiple myeloma and visceral leishmaniasis in the dog: A comparison of two cases

The term monoclonal gammopathy (MG) suggests the presence of clonal immunoglobulins in blood serum that are recognized as narrow spikes in the β and/or γ region of the electrophoretic pattern of serum. In the dog, MG is rare and is associated with a heterogeneous group of diseases that include multiple myeloma (the most common source of MG) as well as infectious and chronic inflammatory diseases such as Leishmaniasis. In this paper, two cases of MG are described: the first case is associated with multiple myeloma of monoclonal component type IgA/λ, with the latter rare in dogs, and the second case involves MG that developed 3 years after an initial diagnosis of Leishmaniasis.

     

Pancytopenia in a cat with visceral leishmaniasis

Abstract: A 4‐year‐old, domestic shorthair, female spayed cat was presented for decreased appetite and depression. Severe pancytopenia with erythrocyte autoagglutination was found. The cat was seronegative for feline immunodeficiency and leukemia viruses. Immune‐mediated hemolytic anemia was suspected but no response to treatment with a blood transfusion, enrofloxacin, and prednisone was observed. Blood and bone marrow smears obtained 11 days later contained Leishmania amastigotes in the cytoplasm of neutrophils and macrophages, respectively. Serologic and PCR testing of peripheral blood confirmed infection with Leishmania infantum. Despite treatment, the cat worsened clinically and was euthanized. At necropsy, visceral dissemination of the parasite was confirmed. The findings in this case indicate that visceral leishmaniasis should be considered as a differential diagnoses in cats with pancytopenia in areas endemic for Leishmania. In addition, amastigotes may be observed in peripheral blood neutrophils.     

Neutropenia associated with osteomyelitis due to Hepatozoon canis infection in a dog

A 4-year-old, intact male Shiba dog was referred to Yamaguchi University Animal Medical Center, Yamaguchi, Japan, for the following complaints: anorexia, lethargy, intermittent fever, gingival bleeding and abdominal purpura. The dog presented with persistent neutropenia. Histopathological examination of a bone marrow sample revealed round to oval structures that resembled Hepatozoon micromerozoites and formed a "wheel-spoke" pattern. Furthermore, mature neutrophils were observed around these structures. PCR and sequencing using bone marrow aspirate confirmed Hepatozoon canis (H. canis) infection. These findings suggest that the neutropenia observed in this case was associated with osteomyelitis due to H. canis infection. This is the first report of neutropenia associated with H. canis infection. H. canis infection can be included in the differential diagnosis in canine cases of neutropenia in areas where the disease is endemic.     

Drug eruption associated with sulfonamide treatment of vertebral osteomyelitis in a dog.

Drug eruption was diagnosed in a 4-year-old German Shepherd Dog being treated with sulfonamides for vertebral osteomyelitis due to infection with Nocardia spp. The eruption was characterized by generalized, pruritic, eczematous dermatitis. Diagnosis was based on a history of repeated exposure to sulfonamides, skin biopsy findingd, and clinical recovery on cessation of sulfonamide therapy.     

Destructive polyarthritis in a dog with leishmaniasis

The clinical history and diagnosis of a dog with leishmaniasis involving both elbow joints and the skin is described. The dog, a female, five-year-old crossbreed, had been imported from Majorca (Balearic Islands, Spain) four years before the diagnosis was made. For two years, the dog had had bilateral forelimb lameness. Physical examination revealed swollen, painful and crepitating elbow joints. Furthermore, an ulcerating dermatitis was found on the concave surface of the left pinna and necrotising margins on both ears. Radiographs of the elbow joints revealed complete destruction of the joint surfaces with dislocation of the radius and the ulna, compatible with severe osteolytic arthritis. The diagnosis of leishmaniasis was confirmed by a direct agglutination test.     

Surgical treatment of a vertebral fracture associated with a haematogenous osteomyelitis in a dog.

A seven-month-old Rottweiler was referred for a diagnosed femoral neck fracture and a suspected vertebral fracture. The simplified neurological examination revealed an acute paraplegia. A discospondyilitis associated with a pathologic fracture of Th11 and a spinal compression, and a haematogenous epiphysitis of the femoral neck were diagnosed based on radiographic and computed tomographic examinations. The vertebral fracture was stabilised using screws and polymethylmetacrylate with gentamycin by a lateral intercostal approach. The dog was able to walk seven days later. A femoral head and neck ostectomy was performed two weeks later. Staphylococcus intermedius was isolated from both sites, which confirmed the diagnosis. The dog was treated with cephalexin (30 mg/kg/d) for six weeks. A telephone interview with owners indicated that no more clinical signs were present four months after the second surgery. Discospondylitis associated with haematogenous osteomyelitis has only been reported in two cases. Paraplegia is an unusual clinical presentation for discospondylitis. The lateral approach (which allowed a direct access to the infected site) and the technique (screws associated with antibiotic-impregnated cement) are unique for surgical treatment of discospondylitis. Although applying cement to an infected area may pose a risk, antibiotic-loaded cement is successfully used in the treatment of chronic osteomyelitis in humans.     

Cryptococcal osteomyelitis in a dog

Osteomyelitis caused by Cryptococcus neoformans was diagnosed in a three-year-old male Irish wolfhound. The case details and radiological findings of radiolucency and periosteal reaction of the left third metatarsal bone had lead to an initial diagnosis of a malignant bone tumour. Biopsy revealed a fungal granuloma and culture identified the causal organism. A four month course of ketaconazole was instigated and the lameness resolved. Twelve months after the end of treatment there was no recurrence of the problem.     

Extranodal gammadelta-T-cell lymphoma in a dog with leishmaniasis

An 8-year-old intact male mongrel dog with alopecia and weight loss was referred to the Veterinary Faculty of Naples. The dog had pale mucous membranes, enlarged prescapular lymph nodes, and splenomegaly. Laboratory abnormalities included anemia, thrombocytopenia, and hyperglobulinemia. Bone marrow aspirate smears contained numerous Leishmania amastigotes and an immunofluorescent antibody titer was strongly positive (1:1280) for leishmaniasis. The dog was treated with a combination of meglumine antimoniate and allopurinol for 60 days and showed clinical improvement. Two months after the end of treatment the dog was again referred because of relapse of leishmaniasis and the presence of a firm subcutaneous mass on the medial right thigh. Based on cytologic examination of fine needle aspirates of the mass, a diagnosis of large-cell lymphoma was made. Flow cytometry of tumor cells revealed gammadelta-T-cell lymphoma with a CD5+, CD3+, TCRgammadelta+, CD4-, CD8-, CD45RA+ immunophenotype. Using nested PCR, amastigotes were not detected in the neoplastic tissue. An association between leishmaniasis and hematopoietic tumors has been described rarely. gammadelta-T cells may be involved in the host response to this parasite, and prolonged antigenic stimulation and chronic immunosuppression (typical of leishmaniasis) play a crucial role in the etiopathogenesis of T-cell lymphoma.     

Sclerosing encapsulating peritonitis in a dog with leishmaniasis

Canine sclerosing encapsulating peritonitis is a rarely reported condition. A 10-year-old male German shepherd dog cross was presented with a history of ascites, vomiting, soft faeces, anorexia and depression. Gathering of the intestinal loops in the middle portion of the abdomen was detected by radiography and ultrasonography. Cytological examination of Giemsa-stained smears from the popliteal lymph nodes revealed Leishmania species. The results of culture of serosanguineous fluid obtained by abdominocentesis were negative for bacteria and fungi. Laparotomy revealed a sac of fibrous tissue encasing most of the intestinal loops and numerous adhesions extending between them. Histologically, an uneven, diffusely thickened, visceral peritoneal membrane was found. A diagnosis of idiopathic sclerosing encapsulating peritonitis was made. The dog was euthanased because the intestinal wall was torn at many sites during dissection of the membrane.