Abdominal CT evaluation of the liver and spleen for staging mast cell tumors in dogs yields nonspecific results

Canine mast cell tumor staging is commonly performed using abdominal ultrasonography and fine‐needle aspiration cytology of masses, lymph nodes, and hepatic and splenic parenchyma. Computed tomography is used for abdominal, thoracic, or whole body imaging in staging mast cell tumors in the authors’ institution enabling evaluation of multiple body areas in one examination. The aim of this study was to compare the CT examinations acquired for staging of mast cell disease to their subsequent liver and spleen cytology findings. Medical records of dogs with primary mast cell tumors that underwent abdominal CT and concurrent liver and spleen aspirates were reviewed. The CT examinations were evaluated for attenuation, size, and margination of the liver and spleen. The relationship between CT findings and cytology results was analyzed. Forty‐nine dogs matched the inclusion criteria: five of forty‐nine dogs with cutaneous mast cell tumors were positive for metastasis from liver and/or spleen aspirates. Of the five dogs with cytological evidence of liver or spleen metastasis, four had normal CT liver attenuation and size, one dog had concurrent primary hepatocellular neoplasia, four dogs had abnormal splenic parenchyma (two nodular and two diffuse heterogeneity), and one dog had a normal attenuation of the spleen. In four dogs, the spleen was subjectively enlarged. Computed tomographic evaluation of the liver showed no consistent pattern associated with mast cell metastasis and did not predict cytology results. Multifocal splenic hypoattenuating lesions more commonly coincided with mast cell metastasis. Sampling of the liver and spleen remains to be considered in the absence of abnormal CT findings for full staging.     

Fine needle aspiration cytology and histologic correlation in canine tumors

Fine needle aspiration biopsy was performed on 147 skin tumors in 119 dogs over a 4-year period. Both air-dried smears (Wright's stain) and wet-fixed smears (Papanicolaou's stain) were prepared from the aspirates from each tumor and the cytological diagnosis was correlated with histology. In 105 tumors, the cytological and histological interpretations agreed. Histologically, there were 36 stromal tumors, including 19 fibrosarcomas and nine hemangiosarcomas. Cytologically, 12 of the fibrosarcomas and five of the hemangiosarcomas were interpreted correctly as malignant tumors. All 11 melanomas and all 37 mast cell tumors were identified correctly cytologically, while nine of the 11 squamous cell carcinomas, 15 of 21 adenocarcinomas and eight of 19 mammary carcinomas were interpreted as malignant using aspiration biopsy. The fine-needle technique also identified 16 dogs with metastases to the regional lymph nodes before surgical biopsies were undertaken. Benign tumors were incorrectly described as malignancies in only three cases.     

Computer tomographic imaging in 4 dogs with primary nasal canine transmissible venereal tumor and differing cellular phenotype

Primary nasal canine transmissible venereal tumor (CTVT) without genital affection is uncommon. The aim of this report was to describe the primary nasal CTVT findings and CT staging in 4 dogs with different cytological phenotypes. Three male dogs and 1 bitch were evaluated for their chronic histories of sneezing, snoring, mucopurulent nasal discharge and nasal deformation. Cytological examination of nasal secretions suggested CTVT, confirmed by histopathological examination and LINE‐1/c‐myc. Males had the plasmacytoid phenotype of CTVT, and the bitch had the lymphocytoid phenotype. CTVT were staged based on the CT findings using modified Adams staging system. The bitch was classified as stage 1, 2 males were classified as stage 3 and 1 male as stage 4. All dogs had a complete tumoral remission after chemotherapy. Plasmacytoid phenotype was identified in cases with most important damage of the nasal cavity. However, the cytological type did not affect the response to chemotherapy.     

Tritrichomonas foetus and Mycoplasma felis coinfection in the upper respiratory tract of a cat with chronic purulent nasal discharge

A 5‐year‐old indoor male neutered Siamese cat was presented with clinical signs of sneezing and chronic bilateral purulent nasal discharge. Multiple nasal cavity swabs were submitted for bacterial cultures, Mycoplasma felis‐DNA qPCR, and cytology. M felisqPCR was positive and cytomorphologic diagnosis was severe, acute, purulent, rhinitis with intralesional protozoal microorganisms consistent with a Trichomonas spp. Nested PCR (nPCR) confirmed the diagnosis of Tritrichomonas foetus. Systemic therapy with doxycycline for M felis and metronidazole for T foetus was started with remission of clinical signs within 2 weeks; however, symptoms relapsed shortly after therapy was discontinued. This study represents the first documented case of T foetus associated with chronic nasal discharge in a cat, which supports the hypothesis that T foetus can live in the nasal cavity. It is also the first reported case of M felis and T foetus coinfection, which indicates that with mycoplasmal feline upper respiratory tract infections, T foetus should be considered as a coinfecting agent.     

Dirofilaria repens—An etiological factor or an incidental finding in cytologic and histopathologic biopsies from dogs

Dirofilaria repens is an endemic, zoonotic parasite of carnivores, causing subcutaneous dirofilariasis, which is mostly asymptomatic. The aim of this study was to describe 22 cases of canine subcutaneous dirofilariasis. The cytologic and histopathologic samples were collected from dogs, which presented with various clinical signs such as cutaneous/subcutaneous nodules, hydropericardium, ascites, and lymphadenomegaly. The cytologic or histopathologic examination revealed purulent, pyogranulomatous, granulomatous or eosinophilic dermatitis/panniculitis, and the presence of D repens microfilariae or adults. The microfilariae or adults were also found incidentally in neoplastic cutaneous or subcutaneous tumors and in a sialocele. For the first time, microfilariae were also detected and described in pericardial and abdominal effusions and in enlarged reactive lymph nodes. Although it is well known that D repens can cause dermatitis and panniculitis in dogs, no previous reports of D repens microfilariae in body cavity fluids were found. The role of this parasite in the accumulation of body cavity fluid or in reactive lymphadenomegaly requires further investigation. Due to its zoonotic potential, and apparently underestimated pathogenicity, each case of canine subcutaneous dirofilariasis should be treated.     

陆地棉与毛棉杂种性状遗传学和细胞学研究

本文研究了陆地棉与毛棉棉种间杂种后代的主要形态特征及Ｆ１花粉母细胞减数分裂中期Ⅰ染色体的行为。结果表明：杂种Ｆ１植株营养生长和生殖生长均旺盛；毛棉的高强纤维性状在杂种早代得到表达，可望通过轮回选择提高现有陆地棉品种的纤维强度；杂种Ｆ１花粉母细胞减数分裂时染色体配对正常，其后代不育原因可能由生理因素不协调造成；杂种后代短日照性强；陆地棉与毛棉亲缘关系比较近，仅在部分染色体间发生分化，存在染色体结构上的差异。