Follow-up studies by peroral gastric biopsies and necropsy in vomiting dogs.

The results of follow-up studies in 139 vomiting dogs are presented. Follow-up studies were performed by biopsies in 34 dogs, by biopsies and necropsy in six dogs and by necropsy only in 99 dogs. The times between the first and the last series of biopsies varied from three to 1042 days and from one to 656 days between the first series of biopsies and necropsy. From the 55 dogs with gastritis in the first series of biopsies, 35 also showed gastritis in the following biopsies or at necropsy. These were mainly severe types of gastritis such as diffuse, hypertrophic or atrophic. Ten dogs with superficial gastritis showed no gastric changes at necropsy, two dogs had edema only and three dogs had gastric changes other than gastritis, such as multiple polyps. In general, carcinoma and lymphosarcoma were found in the biopsies as well as at necropsy, but in three cases of terminal carcinoma only gastritis had been diagnosed initially. In 35 dogs the first series of gastric biopsies showed no pathological changes, but in 22 of these dogs gastritis, ulceration, fibrosis, atrophy, gastric dilation with local necrosis, and perforation or lymphosarcoma of the submucosa were found in the second series of biopsies or at necropsy. Several dogs which did not have gastric changes at necropsy had enteritis or intestinal lymphosarcoma.     

The histological appearance of large intestinal biopsies in dogs with clinical signs of large bowel disease.

Colonic and rectal forceps and excision biopsies of 355 dogs with clinical signs of large bowel disease were investigated. Five percent of the forceps biopsies were unsuitable for examination; all excision biopsies were of good quality. Forceps biopsies were obtained from one to eight sites, up to 60 cm cranial from the anus, while excision biopsies, mostly from tumors, were from the rectoanal region. Slight to severe colitis and/or proctitis was found in 192 dogs (54%). A single type of colitis was seen in 160 dogs; in 53 cases the lesions were local, in 107 cases multiple. A combination of different types of colitis was found in 32 dogs. Atrophic colitis, diffuse colitis and canine histiocytic ulcerative colitis were the most prominent findings, followed by ulcerative, superficial and eosinophilic colitis. Follicular, hypertrophic and aspecific granulomatous colitis were found in only a few cases. Tumors were diagnosed in 57 dogs (16%). Of these tumors 50 were of epithelial and seven were of mesenchymal origin. A high percentage (61%) of the epithelial tumors consisted of adenomas of the rectoanal region. In ten other dogs (3%) a differential diagnosis of lymphosarcoma or colitis had to be made. Colitis and colorectal tumors were more prevalent in Boxers, German Shepherds, Poodles, Great Danes and Spaniels. In the Boxers simple chronic colitis, as well as canine histiocytic ulcerative colitis were more frequently found, the latter especially in females. Other biopsy findings were edema, crypt cysts, hemorrhages, an increased number of intraepithelial lymphocytes and an increased or decreased number of goblet cells.     

A morphometric study of the canine colon: comparison of control dogs and cases of colonic disease.

The microstructure of the canine colon was described morphometrically. The artifacts induced by administration of enemas and biopsy technique were studied by comparing biopsy specimens to tissues obtained at necropsy from 15 normal dogs. Biopsies from control dogs and clinical cases of colonic disease were then evaluated quantitatively, and histological abnormalities which might clarify mechanisms underlying large bowel dysfunction in the dog were sought. In control dogs, gland length and diameter, epithelial, goblet cell and mucosal mast cell numbers, and intraepithelial lymphocyte and mitotic indices were remarkably uniform throughout the colon. Minor variations were found in the proximal and distal regions of the colon. An apparent shortening of glands, and a reduction in mucous goblets and intraepithelial lymphocytes in biopsies were attributed to suboptimal orientation and irritation caused by enemas. The only significant difference from controls identified by morphometric analysis of biopsies from clinical cases was fewer epithelial cells lining longitudinal sections of glands. It was concluded that failure to identify morphometric variations in the colonic mucosa of clinical cases might reflect either a biased, homogeneously mild clinical syndrome in this group, or the possibility that in many of the clinical cases, a functional rather than physical abnormality was involved. The proprial inflammatory cell population was not examined quantitatively; further investigation of this component is merited.     

CT-GUIDED BRAIN BIOPSY USING A MODIFIED PELORUS MARK III STEREOTACTIC SYSTEM: EXPERIENCE WITH 50 DOGS

This report describes the results of CT-guided stereotactic brain biopsies performed on 50 consecutive dogs using a modified Pelorus Mark III Stereotactic System. Based on available histopathologic samples (stereotactic biopsy [n = 50], surgery [n = 17], necropsy [n = 9]) the patient population consisted of 34 dogs with primary brain tumors, 2 with invasive nasal adenocarcinomas, and 13 with non-neoplastic brain lesions. Brain tissue was not obtained from one dog. In 22 dogs a final diagnosis was made from tissue subsequently obtained from surgical resection or at necropsy. The final diagnosis was in agreement with the stereotactic biopsy diagnosis in 20 of these 22 dogs. In 17 other dogs without follow-up, stereotactic biopsy provided a diagnosis of a specific primary brain tumor subtype. Postoperative complications associated with the biopsy procedure were assessed in 41 dogs. The other 9 dogs either went directly to surgery (n = 7) or were killed (n = 2) immediately after the biopsy procedure. Thirty-six dogs recovered without apparent clinical complications. Postoperative clinical complications in the remaining 5 dogs included transient epistaxis (1 dog), transient exacerbation of cerebellar signs (1 dog), obtundation progressing to coma (1 dog), and medically uncontrollable seizures (2 dogs). The latter 3 dogs with severe neurologic complications all had large primary brain tumors and had been receiving high doses of phenobarbital and glucocorticoids to control seizures at the time of biopsy. These results suggest that this CT-guided biopsy procedure can provide an accurate pathologic diagnosis of brain lesions detected by CT and MR neuroimaging. Further refinement of both technique and case selection is expected to reduce the rate of clinical complications and to improve the accuracy of the procedure.     

The histological appearance of peroral gastric biopsies in clinically healthy and vomiting dogs.

A survey of the histology of gastric biopsies in 501 dogs, consisting of 19 clinically healthy dogs and 482 vomiting dogs is presented. Whole stomachs of four young clinically healthy laboratory dogs were used as controls. Eleven percent of forceps biopsies were unsuitable for examination; all suction biopsies were of good quality. Slight to severe gastritis was found in 168 vomiting dogs (35%), whereas five dogs (26%) of the clinically healthy group showed a mainly slight gastritis. Superficial and diffuse gastritis were the most prominent findings in the 168 dogs with gastritis. A single type of gastritis was found in 114 dogs, a combination of different types in 54 dogs. Gastric atrophy was seen in 23 (5%) vomiting dogs and in three (15%) clinically healthy dogs, atrophy with a slight to severe fibrosis in 21 (4%) vomiting dogs, and in 84 (17%) vomiting dogs and two (11%) healthy dogs, gastric fibrosis was present. Carcinomas were seen in 26 vomiting dogs, of which 17 also had gastritis. A differential diagnosis of granulomatous gastritis/carcinoma had to be made in one case. Seven dogs showed a lymphosarcoma, and in six other dogs a differential diagnosis of lymphosarcoma and/or gastritis was made. One adenomatous polyp was seen. In one clinically healthy dog an adenomyoma was diagnosed. Ulceration was found in 24 dogs, but only five of these lacked other lesions. Other biopsy findings were pseudopyloric metaplasia, hyperplasia, cysts, calcification and edema. Some dogs showed "antralization".     

ULTRASONOGRAPHY OF ALIMENTARY LYMPHOSARCOMA IN THE CAT

Clinical, radiological and ultrasonographic findings from 22 cats with gastrointestinal lymphosarcoma were reviewed. The most common clinical findings were anorexia, weight loss, vomiting, lethargy, depression, fever, anemia and a palpable abdominal mass. Abdominal radiographs of 12 cats revealed a mass associated with the gastrointestinal tract and/or mesentery, and decreased serosal detail, suggestive of peritoneal effusion. The most common ultrasonographic finding was transmural gastric or intestinal thickening associated with loss of normal wall layering, reduced wall echogenicity and localized hypomotility. As is noted in people, other patterns such as transmural-segmental, transmural-nodular, transmural-bulky and mucosal infiltration were represented. In 3 cats, mesenteric lymph-adenopathy was responsible for most of the mass-effect. Fine-needle aspiration biopsy, automated microcore biopsy, endoscopic biopsy or necropsy confirmed the diagnosis of lymphosarcoma in all cats. Chemotherapy was instituted in 19 cats. Only 6 cats had a complete response to treatment. The results of this study indicate that ultrasonography is a valuable tool for the diagnosis of feline alimentary lymphosarcoma and that biopsies can be obtained under ultrasonographic guidance.     

Association between anal furunculosis and colitis in the dog: preliminary observations

Treatment of anal furunculosis in dogs is often unsatisfactory and may be associated with significant recurrence and complications. This may be compounded by the simultaneous presence of colitis in affected animals. Clinical signs associated with colitis and anal furunculosis may be similar, including faecal tenesmus, dyschezia and haematochezia. To examine the incidence of concurrent anal furunculosis and colitis, colonic biopsies were collected from 18 dogs referred for treatment of anal furunculosis. Nine dogs (50 per cent) had a histopathological diagnosis of colitis. Clinical signs more indicative of colitis than anal furunculosis (increased frequency of defecation, mucus in faeces and diarrhoea) were not observed more frequently in dogs with confirmed colitis compared with those with furunculosis alone. Therefore, while an association between colitis and anal furunculosis may exist, clinical signs alone cannot be used as an indicator of the presence of colitis in cases of anal furunculosis. The authors recommend that colonic biopsies should be undertaken in all dogs presented with anal furunculosis. Whether specific treatment of colitis in dogs with histopathological evidence of colitis improves the outcome of treatment for anal furunculosis awaits further study.     

Percutaneous biopsy of abdominal organs under ultrasound guidance

Percutaneous sampling of one or more abdominal organs was performed under ultrasound guidance in 89 dogs and 16 cats. Tissue core samples were considered to be of diagnostic quality in 92 per cent of hepatic and 100 per cent of renal biopsies. Core biopsies were collected from the prostate in only three cases but each was adjudged of diagnostic quality. The technique allowed a definitive diagnosis or normal tissue to be confirmed in 65 per cent of animals undergoing hepatic biopsy, 83 per cent undergoing renal biopsy and 82 per cent undergoing prostatic biopsy or aspiration. Few complications occurred which could be ascribed with certainty to the procedure. One dog with extensive hepatic necrosis died one week after the biopsy, but necropsy examination was denied. One severely debilitated cat did not recover from general anaesthesia. One dog underwent aspiration of a sterile intraprostatic cyst, and developed prostatic abscessation one week later; prostatic carcinoma was subsequently found. Careful selection and preparation of patients for biopsy are essential. With this caveat, ultrasound-guided sampling of abdominal organs is a useful technique allowing a definitive diagnosis in a high proportion of cases. The technique is minimally invasive and the complication rate low.     

Ultrasound- guided catheter biopsy of the lower urinary tract: technique and results in 12 dogs

Ultrasound-guided catheter biopsy of lesions affecting the lower urinary tract was attempted in 12 dogs with mucosal lesions affecting the bladder [nine] or urethra (three). Histological biopsies were obtained by catheter biopsy in 10 dogs, enabling diagnosis of transitional cell carcinoma in five, papilloma in two, prostatic carcinoma in two and chronic cystitis in one. Cytological samples alone were obtained in two dogs, one of which enabled a diagnosis of transitional cell carcinoma; the other contained evidence of haemorrhage and inflammation, but squamous cell carcinoma was found in a subsequent exci-sional biopsy. Intravesicular haemorrhage after biopsy was observed ultrasonographically in two dogs. Ultrasound guidance enables accurate determination of biopsy catheter position. The size of biopsies obtained by this method may limit the accuracy of histological diagnosis.     

Acute blindness associated with intracranial tumors in dogs and cats: eight cases (1984-1989)

Rostral and middle cranial fossa tumors affecting the optic chiasm and resulting in acute visual deficits were diagnosed in 7 dogs and 1 cat. Blindness and dilated nonresponsive pupils were the primary signs in all animals. Other concurrent neurologic deficits were either absent or were equivocal. Behavioral changes, including signs of depression and lethargy, were noticed in 1 dog and the cat subsequent to the onset of blindness. Retinal function was assessed as normal by electroretinography in all animals. The histologic necropsy diagnosis was pituitary carcinoma in 1 dog and the cat and paranasal sinus carcinoma with intracranial extension in 1 dog. A cytologic diagnosis of polycentric lymphosarcoma affecting the optic chiasm was diagnosed in 1 dog. In the remaining 4 dogs, results of computed tomographic imaging or endocrine function testing suggested pituitary gland neoplasia. Four dogs were treated with cobalt-60 radiation or chemotherapy. There was partial return of visual function in only 1 of the dogs treated with radiation.     

Retrospective study on the diagnostic value of full-thickness biopsies from the stomach and intestines of dogs with chronic gastrointestinal disease symptoms

An evaluation of histologic findings in full-thickness biopsies from the gastrointestinal tract (GIT) from 64 dogs with chronic GIT disease symptoms was performed. In the majority of cases (38/64; 59%), intestinal lymphangiectasia and mucosal edema of unknown etiology were present. In 10 dogs (16%) an eosinophilic colitis, either alone or together with gastritis and/or enteritis, was found. In 5 dogs (8%) lymphocytic-plasmacytic enteritis or enterocolitis was diagnosed. Five dogs (8%) had an intestinal T-cell lymphoma. Samples from the remaining cases were histologically normal or did not allow for a final diagnosis. In contrast to reports about findings in endoscopic biopsies (which often are of varying quality or inadequate for diagnosis), in the majority of cases of this study, examination of full-thickness biopsies from the GIT allowed us to make a definitive histopathologic diagnosis. Furthermore, the study revealed that transmural biopsies are very helpful for diagnosing lymphoma.     

Disseminated large granular lymphoma in a horse

A 21‐year‐old pony gelding presented for a 5 week history of diarrhoea, inappetance, progressive weight loss and lethargy. Differential diagnoses for chronic diarrhoea and weight loss in horses include: chronic salmonellosis, sand enteropathy, enterolith, parasitism (strongylosis, cyathostomiasis), NSAID induced ulcerative colitis, inflammatory bowel disease (granulomatous, lymphocytic‐plasmacytic or eosinophilic enterocolitis), gastrointestinal neoplasia (lymphosarcoma, squamous cell carcinoma), antibiotic associated clostridial overgrowth, altered diet or bacterial fermentation, peritonitis, Strongylus vulgaris induced arteriopathy (now quite rare) and abdominal mass or abscess. In this gelding, ante mortem diagnosis of CD3⁺ intestinal large granular lymphoma was made via cytology of abdominal fluid and immunohistochemistry of a rectal muscle biopsy. This report details the clinical, cytological and immunophenotypic findings of a case of large granular lymphoma in a horse.     

ULTRASOUND-GUIDED FINE-NEEDLE ASPIRATION BIOPSY OF BONE LESIONS: A PRELIMINARY REPORT

The purpose of this preliminary study was to determine the feasibility of ultrasound-guided fine-needle aspiration biopsy of suspected neoplastic lesions of bone. Ultrasound-guided fine-needle aspiration biopsy samples were obtained in 23 patients (22 dogs and one cat) with radiographic evidence of a destructive or destructive/productive bone lesion. The lesions were located in the appendicular skeleton in 20 patients and in the axial skeleton in three. Histopathology from tissue core biopsies and/or necropsy was not deemed necessary in 11 patients where ultrasound-guided fine-needle aspiration biopsy results were conclusive for neoplasia. A cytologic diagnosis from ultrasound-guided fine-needle aspiration biopsy was confirmed by histologic samples obtained at surgery or necropsy in five patients. In one of these five, ultrasound-guided fine-needle aspiration biopsy samples were diagnostic for sarcoma when tissue-core biopsy was inconclusive. Both ultrasound-guided fine-needle aspiration biopsy and tissue core biopsy techniques were inconclusive in one patient. Ultrasound-guided fine-needle aspiration biopsy samples were nondiagnostic in five patients where a follow-up histopathologic diagnosis of neoplasia was made. It was concluded that ultrasound-guided fine-needle aspiration biopsy of bone, if diagnostic, may help avoid the need for a tissue-core biopsy in some instances. However, a negative ultrasound-guided fine-needle aspiration biopsy sample does not rule out neoplasia. A negative ultrasound-guided fine-needle aspiration biopsy should be followed by a tissue-core biopsy and histologic analysis in all patients. Ultrasound-guided fine-needle aspiration biopsy seems to be a promising technique for the diagnosis of bone lesions.     

Immunophenotypic and histological characterisation of 109 cases of feline lymphosarcoma

OBJECTIVE: To determine and analyse the immunophenotype and histological appearance of naturally occurring cases of lymphosarcoma in Australian cats. DESIGN: A prospective multi-institutional study of naturally occurring feline lymphosarcoma. METHODS: One hundred and eighteen cats were referred for diagnosis and/or management of suspected lymphosarcoma. Tissue samples for histopathological analysis and immunophenotyping were collected as biopsies or at necropsy from 109 cases. Histological classification of the neoplasms followed the Working Formulation Classification System. Four multi-species cross-reactive antibodies were used to classify tumours as having a B or T cell phenotype. RESULTS: Seventy-six (70%) cases were B cell tumours and 28 (26%) were T cell tumours. The remaining 5 (4%) specimens failed to stain with the four antibodies. Histologically, 11 (10%) cases were classified as low-grade, 72 (66%) were medium-grade and 26 (24%) were high-grade tumours. There were no significant associations between age and either histological grade or immunophenotype. Mediastinal and leukaemic cases were significantly more likely to be T cell tumours (P < 0.001 and P < 0.001, respectively). CONCLUSIONS: In contrast to previously documented studies in the cat, the majority of cases of lymphosarcoma were of B cell phenotype and intermediate histological grade. Based on our data, the histological phenotype of lymphosarcoma is unlikely to predict immunotype, nor are cases of certain immunotypes likely to be of specific histological subtype. Considered in relation to previous reports, the findings suggest that epidemiological factors operating in these cats to produce lymphosarcoma may be different to those operating in North American and UK cat populations.     

Comparison of core needle biopsy and fine-needle aspiration of enlarged peripheral lymph nodes for antemortem diagnosis of enzootic bovine lymphosarcoma in cattle

OBJECTIVE: To determine whether antemortem core needle biopsy and fine-needle aspiration of enlarged peripheral lymph nodes could be used to distinguish between inflammation and lymphosarcoma in cattle. DESIGN: Prospective study. ANIMALS: 25 cattle with enlarged peripheral lymph nodes. PROCEDURES: Antemortem biopsies of the selected lymph nodes were performed with an 18-gauge, 12-cm core needle biopsy instrument. Fine-needle aspirates were performed with a 20-gauge, 4-cm needle. Specimens were analyzed by pathologists who were unaware of clinical findings and final necropsy findings, and specimens were categorized as reactive, neoplastic, or nondiagnostic for comparison with necropsy results. RESULTS: Sensitivity and specificity of core needle biopsy ranged from 38% to 67% and from 80% to 25%, respectively. Sensitivity of fine-needle aspiration ranged from 41% to 53%, and specificity was 100%. Predictive values for positive test results ranged from 77% to 89% for core needle biopsy and were 100% for fine-needle aspiration. Predictive values for negative test results were low for both core needle biopsy and fine-needle aspiration. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that core needle biopsy and fine-needle aspiration can aid in the antemortem diagnosis of bovine enzootic lymphosarcoma. Results of fine-needle aspiration of enlarged peripheral lymph nodes were more specific and more predictive for a positive test result than were results of core needle biopsy.     

ULTRASONOGRAPHIC APPEARANCE OF SPLENIC DISEASE IN 101 CATS

The sonographic findings in 101 cats with splenic abnormalities are presented. Diagnosis was made by ultrasound-guided fine needle aspirate or fine-needle biopsy (n = 91), ultrasound-guided core biopsy (n = 1), surgical core biopsy (n = 1), or necropsy (n = 10). Two cats had more than one diagnostic procedure (fine needle aspirate and necropsy or core biopsy and necropsy). The splenic abnormalities included lymphosarcoma (n = 30), mast cell tumor (n = 27), extramedullary hematopoiesis and/or lymphoid hyperplasia (n = 27), epithelial tumors (n = 6), mesenchymal tumors (n = 4), malignant histiocytosis (n = 2), myeloproliferative disease (n = 2), pyogranulomatous inflammation (n = 2), erythroleukemia (n = 1), eosinophilic syndrome (n = 1), hematoma (n = 1), and granulomatous splenitis (n = 1). Three cats had more than one splenic abnormality (mast cell tumor and metastatic carcinoma, pyogranulomatous inflammation and lymphoid hyperplasia, histiocytic lymphosarcoma, and lymphoid hyperplasia). Pathognomonic changes were not seen for any of the diseases.     

Nutritional Management of Idiopathic Chronic Colitis in the Dog

Idiopathic chronic colitis was diagnosed in 13 dogs. Owners sought veterinary care because of semiformed to liquid feces, fresh blood and/or mucus in the feces, tenesmus, increased frequency of defecation, vomiting, weight loss, and flatulence in their dogs. A lymphocytic, plasmacytic infiltration in the colonic lamina propria was found on colonic biopsy specimens. Signs resolved in all 13 dogs after they were fed a low residue, easily assimilated, relatively hypoallergenic diet. In 11 dogs, two commercial diets not previously fed to these dogs were successfully substituted for the initial test diet, without causing recurrence of signs. Only two of these 11 dogs subsequently tolerated a switch to diets that had been fed at the time of onset of signs of colitis. All 13 dogs have been successfully managed from 2 months to 28 months following the initiation of dietary therapy. The results of these dietary challenges strongly suggest a dietary role in the pathogenesis of this disorder, and also illustrate the importance of dietary therapy in the management of idiopathic chronic colitis.     

Doxorubicin-lnduced Cardiotoxicosis Clinical Features in 32 Dogs

Clinical cardiac abnormalities developed in 32 of 175 dogs that had various malignancies and were treated with doxorubicin: 31 dogs had electrocardiographic abnormalities including arrhythmias and nonspecific alterations in the R wave, ST segment, or QRS duration and 7 dogs had congestive heart failure. All seven dogs that had congestive heart failure died within 90 days. At necropsy, 13 of 32 affected dogs had noninflammatory myocardial degeneration, myocytolysis, vacuolation, and/or fibrosis and there was intramural coronary arteriosclerosis in all 13. Five dogs with lymphosarcoma were in complete clinical remission when they died of doxorubicin-induced cardiomyopathy, but the overall survival times of the lymphosarcoma subset was nevertheless longer than in previous studies. The clinical use of doxorubicin in the dog can cause cardiotoxicosis but the therapeutic benefit appears to outweigh risks in most dogs.     

ASSOCIATION BETWEEN RENAL HYPOECHOIC SUBCAPSULAR THICKENING AND LYMPHOSARCOMA IN CATS

The purpose of this study was to investigate the association between renal hypoechoic subcapsular thickening observed ultrasonographically and the presence of renal lymphosarcoma in cats. The ultrasonography database was retrospectively searched for cats that underwent ultrasound examination and ultrasound guided needle renal aspirate, renal biopsy, or necropsy. One radiologist unaware of the final diagnosis evaluated the images for the presence of hypoechoic subcapsular thickening and other abnormal findings. Fifty-four cats met the inclusion criteria. Hypoechoic subcapsular thickening was found in 21 cats of which 17 had lymphosarcoma; the remaining four cats had a different diagnosis. Eleven out of 33 cats without hypoechoic subcapsular thickening were positive for lymphosarcoma, and the rest had a different diagnosis. There was a significant association between hypoechoic subcapsular thickening and renal lymphosarcoma (P = 0.001). The positive predictive value of hypoechoic subcapsular thickening for lymphosarcoma was 80.9% and the negative predictive value was 66.7%. The sensitivity and specificity of hypoechoic subcapsular thickening for the diagnosis of renal lymphosarcoma were 60.7% and 84.6%, respectively. The results of this study indicate that the presence of hypoechoic subcapsular thickening in feline kidneys is associated with renal lymphosarcoma.     

Thymic lymphosarcoma in three heifers

Three heifers with the thymic form of lymphosarcoma were examined. In each of the 3 cases, fever, bloat, and jugular venous distention had developed. Detectable antibody to bovine leukosis virus was not found on agar gel immunodiffusion testing in any of the cases. Thymic lymphosarcoma was confirmed by necropsy and histologic examination. Thymic lymphosarcoma must be considered in the differential diagnosis in heifers with fever, bloat, and jugular venous distention.