Variation among pathologists in histologic grading of canine cutaneous mast cell tumors.

Ten veterinary pathologists at 1 veterinary institution independently assigned histologic grades to the same 60 canine cutaneous mast cell tumors (MCTs). There was significant variation among pathologists in grading the MCTs (P < 0.001). The probability of assigning a low grade was significantly higher for the pathologists in this study who use a published reference for histologic grading of canine cutaneous MCTs that allows subcutaneous MCTs or MCTs with mitotic figures to be included in the low-grade category (P < 0.0001 and P < 0.0001, respectively).     

Catheter-assisted retrieval of urocystoliths from dogs and cats.

To facilitate medical dissolution of uroliths in dogs and cats, urinary catheters may be used to retrieve urocystoliths for quantitative mineral analysis. Following transurethral catheterization of the urinary bladder and distention of the bladder with physiologic saline solution, urine and saline solution are aspirated into a syringe while an assistant vigorously and repeatedly moves the abdomen up and down. Dispersion of small uroliths throughout fluid in the bladder lumen facilitates their aspiration into the catheter and syringe.     

Evaluation of the effect of routine histologic processing on the size of skin samples obtained from dogs

OBJECTIVE: To determine the effects that routine histologic processing has on the dimensions of samples of normal skin of dogs and assess whether the inclusion of a muscle or fascial layer in such samples alters those effects. SAMPLE POPULATION: Skin samples obtained from 6 medium-sized adult dogs with grossly normal skin. PROCEDURE: From each dog, skin samples (with or without underlying fascia or muscle) were obtained from 3 sites bilaterally (6 samples/dog) and processed routinely for histologic evaluation; their dimensions were measured at intervals during the experiment. RESULTS: As a result of processing, skin samples decreased in size (combined percentage change in length and width) and increased in thickness, compared with their original dimensions. Samples without fascia or muscle decreased in size by 21.1% to 32.0% and increased in thickness by 45.1 % to 75.8%. The site of sample origin influenced processing-associated changes in sample size but did not affect the change in thickness. Decreases in dimensions did not vary with inclusion of fascia but did vary with inclusion of muscle. The change in thickness did not vary with inclusion of a layer of fascia or muscle. CONCLUSIONS AND CLINICAL RELEVANCE: Processing of skin samples obtained from dogs for histologic evaluation can cause changes in sample dimensions; samples may decrease in length and width by as much as 32% and increase in thickness by 75.8%, compared with their original dimensions. The presence of muscle in canine skin samples can restrict the amount of shrinkage in length or width associated with processing.     

Laparoscopy in dogs and cats.

Laparoscopic techniques have been developed in veterinary medicine for noninvasive evaluation of several organs, including liver, extrahepatic biliary system, pancreas, kidneys, spleen, bowel, and genitourinary tract. Biopsy procedures of these organs with minimal risk can be performed in most patients. This article reviews the equipment and technique necessary to perform laparoscopy in dogs and cats.     

Hemangiosarcoma in dogs and cats.

Hemangiosarcoma (HSA, including angiosarcoma and malignant hemangioendothelioma) is a highly malignant tumor derived from the endothelial cell line and is characterized by early and aggressive metastasis. HAS is a common tumor type in dogs, but is rare in other species. Treatment options include surgery, chemotherapy, and possibly radiation, but survival times are invariably short (usually < 1 year), except for patients with superficial dermal HSAs. Further options to treat this tumor type are currently being investigated.     

Primary and metastatic carcinomas in the digits of cats

In the period 1993-1998, digital carcinomas in 64 cats were examined. In all animals primary complaints were painful digit(s). Eight cats had a primary squamous cell carcinoma which involved one digit or two adjacent digits of one leg. Fifty-six cats had metastases of a pulmonary carcinoma in the digits, and in general multiple digits of different legs were involved. In many of these cats metastases also occurred in other organs, including the skin and muscles. No primary sweat gland carcinomas of the digits were seen. Primary squamous cell carcinomas of the digits were characterized by cornification and the absence of PAS-positive cells, PAS-positive secretory material. Immunohistochemically, these neoplasms stained negative with the monoclonal antibody CAM 5.2 directed against Keratin 8 (K 8). The metastases of pulmonary carcinomas to the digits showed one or more of the following histological features: goblet cells, ciliated epithelial cells, PAS-positive cells or lakes, and/or a PAS-positive lining of luminal membranes and no cornification. Immunohistochemically, they showed positive staining for CAM 5.2 (K8). Thoracic radiographs from three cats with a primary squamous cell carcinoma showed no abnormalities, whereas all cases of metastases from a pulmonary carcinoma to the digits available for follow-up showed evidence of a primary pulmonary carcinoma on radiography and/or postmortem examination (25 out of 56). The conclusion of this study was that most carcinomas in the digits of cats were metastases of a primary pulmonary carcinoma (87.5%). Primary squamous cell carcinomas occurred infrequently. The prognosis of metastases of a pulmonary carcinoma in the digits is poor with an average survival time of 4.9 weeks, in contrast to 29.5 weeks in cats with a squamous cell carcinoma. These data stress the importance of taking thoracic radiographs of cats with digital tumours before surgical intervention.     

Fluorescence serologic and histologic studies of antigen distribution in parvovirus infections in dogs and cats]

In organs known as replication sites of parvovirus and additionally in stratified squamous epithelia from different regions of 35 dogs with lethal parvovirus enteritis and 19 cats with lethal panleukopenia the distribution of antigen and the prevalence of histologic lesions were studied by immunofluorescence and histologic techniques. The findings showed no striking differences between dogs and cats. Antigen was found in the epithelia of the dorsal side of the tongue (96.3%), pharynx (81.0%), esophagus (50.0%), ventral side of the tongue (20.4%) and planum nasale (5.6%). The epithelia of the skin and the mucous membranes of the male and female genital organs never contained antigen. Moreover antigen was detected in the mucosa of the small intestine (85.2%), bone marrow (81.6%), spleen (79.6%), thymus (66.7%), mesenteric lymph nodes (60.4%), tonsilla palatina (58.5%), smooth muscle cells of the tunica muscularis of the small intestine (9.3%) and myocardium (1.9%). The histologic lesions found in intestinal mucosa, lymphatic tissues, bone marrow and myocardium are in accordance with literature. The tunica muscularis of the small intestine and the epithelium of tongue, pharynx and esophagus contained intranuclear inclusion bodies, the epithelium of tongue and pharynx showed necroses additionally. Tongue- and esophagus-erosions as well as -ulcers reported mainly in panleukopenia according to our results may be explained as a sequel of parvovirus infection of the epithelia of these organs. The prevalence of antigen and intranuclear inclusion bodies in the myocardium and smooth muscle cells of the small intestine--tissues with low or no mitotic activity,--allows to question the postulate of the parvoviruses' exclusive affinity to rapidly dividing cells.     

A prospective study of postoperative surgical site infections in dogs and cats

OBJECTIVE: To assess postoperative surgical site infection (SSI) rate and to identify associated predictive factors. STUDY DESIGN: Prospective clinical study. ANIMALS: Dogs and cats that had surgery (1010 interventions) during 58 weeks from April 1999 to June 2000. METHODS: Data sheets were completed by clinicians. Patients were controlled for clinical evidence of SSI at suture removal. Two definitions of SSI ("infection" and "infection/inflammation") were developed specifically for this study and used for statistical analysis. Logistic regression models were built in order to identify significant predictive factors for SSI. RESULTS: Wounds with "infection/inflammation" occurred in 5.8% and "infected" wounds in 3% of patients. The outcome "infection" was associated with 3 major risk factors (duration of surgery, increasing number of persons in the operating room, dirty surgical site) and 1 protective factor (antimicrobial prophylaxis). The outcome "infection/inflammation" was associated with 6 significant factors (duration of anesthesia, duration of postoperative intensive care unit stay, wound drainage, increasing patient weight, dirty surgical site, and antimicrobial prophylaxis). CONCLUSIONS: SSI frequency in companion animals is comparable with the frequency observed in human surgical patients. Several significant predictive factors for SSI in small animals surgery were identified. CLINICAL RELEVANCE: Baseline information for SSI surveillance in our hospital and for comparison with other studies was defined. The factors identified may help to predict infections in surgical patients and to take adequate preventive measures for patients at risk.     

Thyroid surgery in dogs and cats.

Thyroid surgery is indicated for malignant and benign neoplasms or hyperplasia of the thyroid glands. A ventral midline cervical approach allows for bilateral thyroid exploration. Care should be taken to avoid the surrounding neurovascular structures and esophagus. Evaluation of both thyroids should be done before proceeding with partial or complete thyroidectomy. Complications of thyroid surgery include intraoperative hemorrhage and clinical signs associated with damage to the recurrent laryngeal nerves, parathyroid blood supply, or parathyroidectomy.     

Unconventional diets for dogs and cats.

Food plays a far more complex role in daily life than simply serving as sustenance. Social and cultural factors along with individual beliefs govern people's eating behaviors, and it is likely that these same factors influence their choice of diet and feeding practices for their pets. Some people seek alternatives to conventional commercial pet foods, including commercially available "natural" diets, raw food diets, and vegetarian diets, in addition to a variety of home-prepared diets. Exploring a person's knowledge and beliefs about feeding pets can aid in understanding her or his motives for seeking alternative and may help in changing those practices when it is in the best interest of the pet to do so.     

Optic neuritis in dogs and cats.

The term "optic neuritis" compromises all diseases of the optic nerve that cause primary demyelination and usually manifest themselves as a sudden visual field defect or total loss of vision in one or both eyes. As in man, the cause of optic neuritis is often difficult to determine in the living animal. Neurologic examination, cerebrospinal fluid analysis, and laboratory tests can be normal. Optic neuritis affects dogs far more frequently than other animal species. This article examines the causes of immune-mediated optic neuritis and etiologic differentials in dogs and cats, with comparisons to human beings and laboratory animal models.     

Insulin therapy for dogs and cats.

Management of diabetic dogs and cats requires a tremendous cooperative effort between the practitioner and the client. Consistency in the handling, availability, and formulations of the different insulins will improve client compliance. In addition to insulin therapy, successful management of the diabetic animal includes the client's perceptions of the animal's health, maintenance of the animal's body weight, consistency in water consumption, and monitoring serial blood glucose concentrations. Serial blood glucose determinations improve the practitioner's ability to identify and address problems associated with insulin therapy, and thereby delay or minimize the complications of long-term diabetes.     

Thyroid tumors in dogs and cats.

The clinical presentation and biologic behavior of thyroid tumors vary widely among dogs, cats, and human beings. Although thyroid tumors in dogs are rare, they are most likely to be malignant. Clinical signs are usually the result of impingement on surrounding structures, and clinical hyperthyroidism is rare. In contrast, hyperthyroidism resulting from benign thyroid proliferation is relatively common among older cats. Malignant tumors are extremely uncommon but have high metastatic potential. Irrespective of the tumor's ability to produce functional thyroid hormone, scintigraphy is often helpful in the diagnosis and staging of thyroid tumors in all three species. Treatment with surgery is a reasonable treatment option for noninvasive tumors. Iodine 131 is a well-established treatment for thyroid nodules in cats, but its effectiveness in dogs is controversial. In dogs, external beam radiation therapy has produced more consistent results in affording local tumor control when surgery is not possible.