Multiloculated solitary (unicameral) bone cyst in a young dog.

A 20-month-old female spayed Staffordshire Terrier (22.3 kg) presented to the Orthopedic Surgery Service at North Carolina State University Veterinary Teaching Hospital for evaluation of a 6-week history of toe-touching to nonweight-bearing lameness in the right hind limb. Radiographs of the right stifle revealed a multiloculated lytic lesion of the distal femur, with a large open lytic zone centrally, numerous osseous septations peripherally, and focal areas of cortical thinning and loss. An aspirate of the right distal femoral lesion yielded mildly cloudy serosanguineous fluid. Cytologic examination of the fluid revealed a pleomorphic population of discrete cells that exhibited marked anisocytosis and anisokaryosis and a variable nuclear-to-cytoplasmic (N:C) ratio, which were interpreted as probable neoplastic cells, with few macrophages, and evidence of hemorrhage. Given the clinical signs of pain, lesion size, and concern for malignant neoplasia, amputation of the right hind limb was performed. Histologically, the lesion had undulating walls 1-3 mm thick with a continuous outer layer of dense fibrous tissue and an inner layer composed of reactive cancellous bone with no cortical compacta remaining. Remnants of thin fibrous or fibro-osseous septa projected from the bony wall into the cyst lumen. The final histologic diagnosis was a benign multiloculated solitary (unicameral) bone cyst of the distal right femur. Based on the histopathologic findings, it was speculated that the cells identified on cytology were a mixture of developing osteoclasts, osteoblasts, endothelial, and stromal cells. This is the first report describing the cytologic examination of a solitary bone cyst in veterinary medicine.

Extreme lymphocytosis with myelomonocytic morphology in a horse with diffuse large B-cell lymphoma.

An 11-year-old, 443-kg Haflinger mare was presented to the North Carolina State University Veterinary Teaching Hospital with a 2-week history of lethargy and a 3-day duration of anorexia, pyrexia, tachycardia, and ventral edema. Severe pitting edema, peripheral lymphadenopathy, and a caudal abdominal mass were noted on physical examination. An extreme leukocytosis (154.3 × 103 /µL) and microscopic hematologic findings suggestive of myelomonocytic leukemia were observed. Serum protein electrophoresis revealed a monoclonal gammopathy and urine protein electrophoresis revealed a monoclonal light chain proteinuria. Necropsy and histopathology confirmed widespread neoplastic infiltration in many organs with a heterogenous population of cells; there was no apparent evidence of bone marrow involvement. Immunohistochemistry confirmed presence of a majority of B cells with a limited antigen expression, admixed with a lower number of T cells. Molecular clonality analysis of IgH2, IgH3, and kappa-deleting element (KDE, B cell) on whole blood and KDE on infiltrated tissues revealed clonal rearrangements, and the KDE intron clones that amplified in blood and in infiltrated tissue were identical. In contrast, the clonality analysis of T-cell receptor γ revealed no clonality on blood cells and infiltrated tissues. In conjunction with the histopathologic changes, the lesion was interpreted to be composed of neoplastic B cells with a reactive T-cell population. Polymerase chain reaction testing for equine herpes virus 5 was negative. The final diagnosis was diffuse large B-cell lymphoma with a marked hematogenous component.

Scanning technology selection impacts acceptability and usefulness of image-rich content.

OBJECTIVE: Clinical and research usefulness of articles can depend on image quality. This study addressed whether scans of figures in black and white (B&W), grayscale, or color, or portable document format (PDF) to tagged image file format (TIFF) conversions as provided by interlibrary loan or document delivery were viewed as acceptable or useful by radiologists or pathologists. METHODS: Residency coordinators selected eighteen figures from studies from radiology, clinical pathology, and anatomic pathology journals. With original PDF controls, each figure was prepared in three or four experimental conditions: PDF conversion to TIFF, and scans from print in B&W, grayscale, and color. Twelve independent observers indicated whether they could identify the features and whether the image quality was acceptable. They also ranked all the experimental conditions of each figure in terms of usefulness. RESULTS: Of 982 assessments of 87 anatomic pathology, 83 clinical pathology, and 77 radiology images, 471 (48%) were unidentifiable. Unidentifiability of originals (4%) and conversions (10%) was low. For scans, unidentifiability ranged from 53% for color, to 74% for grayscale, to 97% for B&W. Of 987 responses about acceptability (n=405), 41% were said to be unacceptable, 97% of B&W, 66% of grayscale, 41% of color, and 1% of conversions. Hypothesized order (original, conversion, color, grayscale, B&W) matched 67% of rankings (n=215). CONCLUSIONS: PDF to TIFF conversion provided acceptable content. Color images are rarely useful in grayscale (12%) or B&W (less than 1%). Acceptability of grayscale scans of noncolor originals was 52%. Digital originals are needed for most images. Print images in color or grayscale should be scanned using those modalities.

Comparison of automated versus manual neutrophil counts for the detection of cellular abnormalities in dogs receiving chemotherapy: 50 cases (May to June 2008).

OBJECTIVE: To determine the frequency of clinically relevant abnormalities missed by failure to perform a blood smear evaluation in a specific subset of dogs receiving chemotherapy and to compare automated and manual neutrophil counts in the same population. DESIGN: Retrospective case series. ANIMALS: 50 dogs receiving chemotherapy with a total nucleated cell count > 4,000 nucleated cells/µL. PROCEDURES: 50 blood smears were evaluated for abnormalities that have strong potential to change the medical plan for a patient: presence of blast cells, band neutrophils, nucleated RBCs, toxic change, hemoparasites, schistocytes, and spherocytes. Automated and manual neutrophil counts were compared. RESULTS: Blood smears from 10 (20%) patients had ≥ 1 abnormalities. Blast cells were identified on 4 (8%) blood smears, increased nucleated RBCs were identified on 5 (10%), and very mild toxic change was identified on 2 (4%). Correlation coefficient of the neutrophil counts was 0.96. Analysis revealed a slight bias between the automated and manual neutrophil counts (mean ± SD difference, -0.43 × 10(3)/µL ± 1.10 × 10(3)/µL). CONCLUSIONS AND CLINICAL RELEVANCE: In this series of patients, neutrophil count correlation was very good. Clinically relevant abnormalities were found on 20% of the blood smears. An automated CBC appears to be accurate for neutrophil counts, but a microscopic examination of the corresponding blood smear is still recommended; further studies are needed to determine whether the detection or frequency of these abnormalities would differ dependent on chemotherapy protocol, neoplastic disease, and decision thresholds used by the oncologist in the ordering of a CBC without a blood smear evaluation.

Effect of a combined aspiration and core biopsy technique on quality of core bone marrow specimens.

For cases requiring both a bone marrow aspirate and core biopsy, using the same needle and site (i.e., a combined technique) can decrease time, expense, and discomfort compared with the independent (direct) collection of each specimen. The benefits of the combined approach should not be achieved at the expense of specimen quality. In this study, core bone marrow samples obtained from the proximal humerus of 26 dogs by a combined technique immediately posteuthanasia were compared with core samples obtained directly from the opposite humerus. Both core samples from each dog were compared for relative overall quality. Biopsies were unsuccessful in four dogs using the combined technique and in one dog by the direct technique. Marrow length was shorter and hemorrhage artifact was more common using the combined technique. There were no differences in cellularity, megakaryocyte count, the myeloid/erythroid ratio (M/E ratio), iron stores, or diagnostic quality. Direct core biopsy remains the ideal technique; however, the degree of compromise was small in the samples obtained from the combined technique. For clinical patients, the advantages of the combined technique must continue to be weighed against potential loss of diagnostic sensitivity.

Comparison of manual polychromatophilic cell and automated reticulocyte quantification in evaluating regenerative response in anemic dogs.

BACKGROUND: Degree of polychromasia and reticulocyte counts are commonly used in veterinary medicine to evaluate response to anemia. The quantitative association between these 2 measurements has not been evaluated. OBJECTIVE: The aim of this retrospective study was to compare automated reticulocyte percents and counts with those of polychromatophilic cells on blood films from dogs. METHODS: Blood films and medical records from 30 clinically healthy dogs and 60 anemic dogs were evaluated. Manual percentage of polychromatophilic cells (MPP) was determined by counting cells in 10 1000× fields, and automated reticulocyte percentage (ARP) was measured using an ADVIA 120 hematology analyzer; absolute polychromatophilic cell and reticulocyte counts were then calculated. Degree of polychromasia, estimated as slight, mild, moderate, marked was documented. Percentages and absolute counts of polychromatophilic cells and reticulocytes were compared using least squares regression and Pearson's correlation coefficients. RESULTS: The reference interval for MPP in healthy dogs was 0.21-0.26%. Correlation between MPP and ARP was highest when all levels were considered (n = 60, r = .98, P < .0001), strong when ARP was > 5% (n = 20, r = .91, P < .0001), and poor when ARP was 1-2% (n = 20, r = .35, P < .0001). Results were similar for comparisons of absolute reticulocyte and polychromatophilic cell counts, with the best correlation found when all levels of counts were analyzed together (r = .96) and for automated reticulocyte counts > 150,000/µL (r = .94). Correlation of estimates of polychromasia with ARP was good (r = .83). CONCLUSION: In anemic dogs MPP can be used for assessment of regeneration, especially in dogs with higher levels of ARP. Standard quantification of reticulocytes is more accurate in dogs with lesser degrees of regeneration.

Thrombocytosis: a retrospective study of 165 dogs.

BACKGROUND: Thrombocytosis has been associated with various conditions, including inflammation, neoplasia, iron deficiency, splenectomy, and drug administration. OBJECTIVE: The aim of this study was to characterize diseases and conditions associated with thrombocytosis in dogs. METHODS: In this retrospective study, dogs with thrombocytosis (platelet count > 600 × 10(3) /µL) and complete medical records during a 1-year period were included, and breed, sex, age, CBC results, alkaline phosphatase and gamma-glutamyltransferase activities in some dogs, administration of glucocorticoids or vincristine, and primary diagnosis were evaluated. RESULTS: Thrombocytosis was found in 240 of 5342 dogs (4.6%), and 165 (3.1%) met inclusion criteria. Thrombocytosis was secondary in all dogs, and underlying diseases and conditions (n,%) were neoplasia (56, 33.9%), inflammation (55, 33.3%), miscellaneous disorders (26, 15.8%), neoplasia plus a second disease (13, 7.9%), endocrine diseases (8, 4.8%), and multiple diseases (7, 4.2%). In dogs with neoplasia, carcinomas (24) and round cell neoplasms (20), especially lymphoma and mast cell tumor, were the most frequent tumors. Inflammatory disorders consisted of immune-mediated disorders (11), neurologic diseases (8), infectious diseases (6), allergic disease (5), orthopedic diseases (4), gastrointestinal diseases (4), and miscellaneous conditions (17). Of the 165 dogs, 73 (44.2%) had received glucocorticoids (55) or vincristine (18) Marked (850-969 × 10(3) platelets/µL) or extreme ( ≥ 970 × 10(3) platelets/µL) thrombocytosis occurred in 24 (14.5%) dogs; 12 (50.0%) had neoplasia. Thromboembolism occurred in 13 (7.9%) dogs. CONCLUSIONS: Thrombocytosis in dogs occurred most frequently secondary to neoplastic and inflammatory diseases and was commonly associated with glucocorticoid and vincristine administration. Thromboembolic complications occurred in a small number of patients. Marked or extreme thrombocytosis was more likely to occur with neoplasia than with other conditions.

Learning-style profiles of 150 veterinary medical students.

Awareness of student learning-style preferences is important for several reasons. Understanding differences in learning styles permits instructors to design course materials that allow all types of learners to absorb and process information. Students who know their own learning style are better able to help themselves in courses taught in a non-preferred method by developing study strategies in line with their preferred learning method. We used the Felder and Solomon Index of Learning Styles to assess the learning-style profiles of 150 veterinary students in three consecutive years. Students were predominantly active (56.7%), sensing (79.3%), visual (76.7%), and sequential (69.3%). Most were balanced on the active-reflective (59.3%) and global-sequential (50%) dimensions, and 61.3% and 54% were moderately to strongly sensing and visual, respectively. Small but significant numbers of students were moderately to strongly intuitive (8.7%), verbal (13%), and global (12%). The most common patterns were active-sensing-visual-sequential (26%), reflective-sensing-visual-sequential (19.3%), active-sensing-visual-global (8.7%), and active-sensing-verbal-sequential (8.7%). Although most students (65.3%) were balanced on one to two dimensions, 77.3% had one or more strong preferences. Our results show that although people have dominant learning-style preference and patterns, they have significant minor preferences and patterns across all dimensions with moderate to strong preferences on each scale. These results indicate that a balanced approach to teaching is essential to allow all students to learn optimally.

Deep and superficial skin scrapings from a feline immunodeficiency virus-positive cat.

An 8-year-old, neutered male, domestic shorthair cat housed at the North Carolina State University, College of Veterinary Medicine, Laboratory Animal Research facility as part of a research colony was examined because of mulifocal skin lesions. The lesions consisted of patchy alopecia with mild crusting of the periauricular region, neck, and dorsum; periauricular excoriations; marked dorsal seborrhea and scaling; and generalized erythematous papules. A moderate amount of ceruminous exudate was present in both ear canals. Results of testing for feline immunodeficiency virus (FIV) were positive. An ear swab specimen and superficial and deep skin scrapings were obtained, mounted with oil on glass slides, and coverslipped for microscopic examination. Two populations of mites were observed: a large population of slender, long (approximately 200 microm), adult mites with long, tapering abdomens that comprised two-thirds of the total body length; and a smaller population of more translucent and shorter mites (approximately 100 microm) with wide, blunt abdomens that had prominent transverse ridges. The interpretation was demodicosis, with Demodex cati and D gatoi co-infection. Histologic sections of biopsies from skin lesions on the neck, dorsum, and periauricular area contained a mild perivascular and perifollicular inflammatory infiltrate composed predominantly of histiocytes, lymphocytes, and plasma cells. Diffusely within the follicular lumina and occasionally within the superficial keratin, a myriad of Demodex organisms were observed. Intrafollicular mites were compatible in appearance with D cati whereas those in the corneal layer were suggestive of D gatoi. Demodicosis is an uncommon disease of cats, and rare cases of dual infection have been documented, occasionally in FIV-infected cats. The dual infection emphasizes the importance of doing both superficial and deep skin scrapings and of recognizing the unique microscopic features of different Demodex mites.

Introduction and evaluation of virtual microscopy in teaching veterinary cytopathology.

Virtual microscopy (VM) uses a computer to view digitized slides and is comparable to using a microscope to view glass slides. This technology has been assessed in human medical education for teaching histology and histopathology, but, to the authors' knowledge, no one has evaluated its use in teaching cytopathology in veterinary medical education. We hypothesize that students will respond positively to the use of VM for viewing cytopathology preparations and that the technology can be successfully used for student assessment. To test this hypothesis, we surveyed students regarding their level of satisfaction with features of the VM system, their preference for use of VM in the curriculum, and the potential influence virtual slides may have on student study habits; student performance on a traditional cytopathology practical examination and a similar exam using VM was evaluated. Our results show that student perception of the VM system is generally very positive, with some concerns about resolution and the need for continued exposure to traditional microscopy. Within the curriculum, students indicated a preference for the option of using virtual slides for studying and take-home exercises. Overwhelmingly, students wanted either hybrid laboratory sessions or sessions using glass slides with virtual slides available for study and review. Students identified many VM test-taking features as advantageous compared with traditional glass-slide practical exams as traditionally administered. However, students indicated a strong preference for continued use of traditional microscopy for graded practical exams. Students may be more likely to study slides in preparation for practical examinations if virtual slides are available. Results also indicate that VM can be used successfully for assessment purposes, but students should receive training in using virtual slides if the technology will be used for assessment.

Gallbladder aspirate from a dog.

A 7-year-old, male, castrated, Labrador Retriever with a history of pancreatitis and inflammatory bowel disease presented for vomiting and anorexia. Serum biochemistry findings were indicative of cholestasis, hepatocellular insult, and decreased hepatic function. Ultrasound examination showed sediment and gas within the gallbladder, and a diagnosis of emphysematous cholecystitis was made. Emergency gallbladder resection was performed. Cytologic examination of bile fluid collected at surgery showed a mixed population of bacteria (bactibilia) together with fungal organisms consistent with Cyniclomyces guttulatus (previously known as Saccharomycopsis guttulatus). Similar fungal organisms were seen on a fecal smear. Bacteria cultured were normal gastrointestinal flora, supporting ascending infection; the fungal organisms were interpreted as incidental. Histopathology of the gallbladder indicated active (suppurative) and chronic (lymphocytic) cholecystitis and sections of liver tissue had evidence of chronic liver disease. A positive liver culture indicated concurrent bacterial hepatitis or cholangiohepatitis. Despite supportive care, the dog continued to decline and was euthanized 30 days later. Necropsy results confirmed end stage liver disease, but an initiating cause was not found. This case highlights the role of bactibilia in the development of acute cholecystitis and the unique cytologic appearance of C guttulatus as an incidental finding in bile fluid.

Cellular composition of bronchial brushings obtained from healthy dogs and dogs with chronic cough and cytologic composition of bronchoalveolar lavage fluid obtained from dogs with chronic cough.

OBJECTIVE: To determine whether bronchial brushings from dogs with chronic cough have increased numbers of goblet cells and WBCs, compared with numbers for healthy dogs, or have differing WBC populations, compared with populations in bronchoalveolar lavage (BAL) fluid obtained from dogs with chronic cough. ANIMALS: 9 healthy dogs and 10 dogs with chronic cough. PROCEDURE: Specimens were collected by use of bronchoscopy. Cellular composition was determined for brushings, and results from dogs with chronic cough were compared with those from healthy dogs. Cellular composition of brushings was compared with composition of BAL obtained from dogs with chronic cough. RESULTS: Brushings from healthy dogs contained a median of 2.9 x 10(6) epithelial cells, comprising 100% epithelial cells (96% ciliated, 3% goblet, and 1% other) and no WBCs. Brushings from dogs with chronic cough had 4.5 x 10(6) epithelial cells, comprising 93% epithelial cells (86% ciliated, 2% goblet, and 12% other). Dogs with chronic cough had significantly greater percentages of WBCs (7%) and neutrophils (6%), compared with values for healthy dogs. Five dogs with chronic cough had no neutrophilic inflammation evident in BAL, but 4 of these had evidence of neutrophilic inflammation in brushings. CONCLUSIONS AND CLINICAL RELEVANCE: Neutrophils, but not goblet cells, were increased in brushings from dogs with chronic cough. Analysis of bronchial brushings provides information about airway inflammation that differs from that found by examination of BAL in some dogs with chronic cough and is a more sensitive indicator of airway inflammation than cytologic examination of BAL in these dogs.

Clinical application of reticulocyte counts in dogs and cats.

Reticulocytes are anucleate immature red blood cells that contain a network of RNA, organelles, and mitochondria, which stain with supravital dyes. Both aggregate and punctate reticulocytes are present in domestic cats, and aggregate reticulocytes are used to assess the degree of regeneration in anemic dogs and cats. Multiple factors influence the degree of regenerative response to anemia. These factors include time of reticulocyte measurement, concurrent diseases, species, and ongoing therapy. Although many automated systems for reticulocyte enumeration exist, manual counts remain the gold standard in veterinary medicine.