Association between ACTH stimulation test results and clinical signs in dogs with hyperadrenocorticism treated with trilostane

Trilostane is the recommended medical treatment for dogs with hyperadrenocorticicm (HAC). The objective of this study was to investigate the association between ACTH stimulation test (ACTHST) results, and relevant clinical signs, in dogs treated with trilostane. A disease-specific questionnaire was developed, which included the owner's assessment of polydipsia, polyuria, polyphagia, panting, and satisfaction with the treatment, based on a 5-response category rating scale. Forty-nine dogs with HAC were prospectively enrolled. Dogs were grouped according to their recheck appointment (first recheck, 710 days after commencement of treatment or change of trilostane dose; second recheck, 4 weeks after the first recheck; third recheck, performed at 3-6 months intervals once the dog was well controlled). At the recheck appointment, the owner's questionnaire responses were recorded, and an ACTHST was performed, along with urine specific gravity measurement. Linear mixed effects models were used to assess differences among the three recheck time points and to test possible associations between ACTHST results and clinical signs. Significant differences between rechecks were present for stimulated cortisol (first to third recheck, P < 0.001; second to third recheck, P < 0.01), polydipsia (first to second recheck, P = 0.001), polyuria (first to second recheck, P < 0.001; first to third recheck, P = 0.001), and owner satisfaction (first to second recheck, P < 0.001; first to third recheck, P < 0.001). Backward stepwise variable elimination did not identify any significant associations between ACTHST results and clinical signs. Therefore, clinical signs of HAC were not predicted based on the ACTHST results.

Comparison of auricular and rectal temperature measurement in normothermic, hypothermic, and hyperthermic dogs

Objective: Measurement of rectal temperature is the most common method and considered gold standard for obtaining body temperature in dogs. So far, no study has been performed comparing agreement between rectal and auricular measurements in a large case series. The purpose of the study was to assess agreement between rectal and auricular temperature measurement in normothermic, hypothermic, and hyperthermic dogs with consideration of different environmental conditions and ear conformations. Materials and methods: Reference values for both methods were established using 62 healthy dogs. Three hundred dogs with various diseases (220 normothermic, 32 hypothermic, 48 hyperthermic) were enrolled in this prospective study. Rectal temperature was compared to auricular temperature and differences in agreement with regard to environmental temperature, relative humidity, and different ear conformations (pendulous versus prick ears) were evaluated using Pearson’s correlation coefficient and Bland-Altman analysis. Results: Correlation between rectal and auricular temperature was significant (r: 0.892; p < 0.01). However, Bland-Altman plots showed an inacceptable variation of values (bias: 0.300 °C; limits of agreement: –0.606 to 1.206 °C). This variation was above a maximal clinical tolerance of 0.3 °C, which was established by experts’ opinion (n = 16). Relative humidity had a significant influence (p = 0.001), whereas environmental temperature did not. Conclusion: Variation between the two methods of measuring body temperature was clinically unacceptable. Clinical relevance: Although measurement of auricular temperature is fast, simple, and well tolerated, this method provides a clinically unacceptable difference to the rectal measurement.

Die Bedeutung der Zytologie für den Nachweis von Knochentumoren bei Hund und Katze

In einer prospektiven Untersuchung (1/2001–4/2002) wurde der Wert der Zytologie für die klinische Diagnostik von Knochentumoren bei Hund und Katze überprüft. Bei 31 Hunden und zwei Katzen mit klinischen und radiologischen Hinweisen auf eine Knochenneoplasie wurden eine Feinnadelaspirationsbiopsie und eine zytologische Untersuchung von Knochengewebe durchgeführt. Die Punktion erfolgte ohne Sedation oder Lokalanästhesie mit einer 20-Gauge-Einmalkanüle (0,9 × 40mm) und einer 5oder 10-ml-Plastikspritze. Bei allen Patienten wurde die zytologische Diagnose durch eine histologische Untersuchung überprüft. Die histologische Untersuchung ergab bei 29 Tieren eine maligne Neoplasie: Osteosarkom (n = 23), undifferenziertes Sarkom (n = 2), maligne Histiozytose (n = 2), Liposarkom (n = 1) und Adenokarzinommetastase (n = 1). Bei vier Patienten wurden nichtneoplastische Knochenveränderungen festgestellt: reparative Knochenveränderungen (n = 3) und Osteomyelitis (n = 1). Bei keinem Tier waren im Zusammenhang mit der Feinnadelaspirationsbiopsie Komplikationen oder deutliche Schmerzreaktionen feststellbar. Bei 8/33 Patienten konnte mit einer Feinnadelaspirationsbiopsie kein auswertbares Zellmaterial gewonnen werden, sodass eine zytologische Untersuchung zunächst nicht möglich war. Eine zytologische Untersuchung von Abklatschpräparaten einer offenen Knochenbiopsie war bei vier dieser acht Tiere durchführbar. Bei 4/33 Tieren gelang es mit der zytologischen Untersuchung nicht, die Dignität der Knochenprozesse zu beurteilen. Mehr als drei Viertel der Patienten, bei denen nicht auswertbare zytologische Präparate vorlagen, wiesen röntgenologische Hinweise auf eine ausgeprägte Sklerosierung des Knochens im Bereich der Läsion auf. Mithilfe der Zytologie konnte bei 24/25 Patienten mit auswertbaren zytologischen Präparaten eine korrekte Diagnose bezüglich der Dignität gestellt werden, während bei einem Hund mit reparativen Knochenveränderungen fälschlicherweise ein Sarkom diagnostiziert wurde. Bei 5/25 Tieren war es mithilfe der Zytologie lediglich möglich, die Dignität korrekt zu beurteilen, während die Bestimmung der Tumorart nicht gelang.

A Multistep Approach in the Cytologic Evaluation of Liver Biopsy Samples of Dogs with Hepatic Diseases

Cytologic criteria were evaluated for their diagnostic value in liver disease in dogs. Therefore, histopathologic and cytologic examination was performed on liver biopsy samples of 73 dogs with liver diseases and 28 healthy dogs. Logistic regression analysis was used to select the measured parameters to be included in a multistep approach. With the logistic regression method, different characteristic cytologic parameters could be defined for each histopathologic diagnosis. In malignant lymphoma of the liver, the presence of large numbers of lymphoblasts with a minimum of 5% of all cells was found. Clusters of epithelial cells with several cytologic characteristics of malignancy intermixed with normal hepatocytes were indicative of metastatic carcinoma or cholangiocellular carcinoma. Liver cells in hepatocellular carcinoma were characterized by a high nucleus/cytoplasm ratio, large cell diameters, increased numbers of nucleoli per nuclei, small numbers of cytoplasmic vacuoles, and frequently, small numbers of lymphocytes. Extrahepatic cholestasis was characterized by excessive extracellular bile pigment in the form of biliary casts, an increased number of nucleoli within hepatocytes, decreased hepatic cell size, and low numbers of lymphocytes. In destructive cholangiolitis, increased numbers of neutrophils and a small mean nuclear size within hepatocytes were seen. Acute and nonspecific reactive hepatitis are diagnosed based on the presence of moderate reactive nuclear patterns, including more pronounced chromatin, prominent nucleoli, increased numbers of inflammatory cells, excluding lymphocytes, and the absence of increased numbers of bile duct cell clusters. Increased number of mast cells also was indicative of nonspecific reactive hepatitis. Important cytologic criteria for the diagnosis of liver cirrhosis, in addition to chronic hepatitis, are intracellular bile accumulation and increased numbers of bile duct cell clusters. In summary, the stepwise approach based on logistic regression presented in this study might be helpful in the objective cytologic diagnosis of hepatic diseases.

Cytology of endoscopically obtained biopsies for the diagnosis of chronic intestinal diseases in cats

OBJECTIVE

To evaluate the diagnostic value of cytology of endoscopically obtained biopsies in cats presented for chronic gastrointestinal complaints with emphasis on the diagnosis of low-grade alimentary lymphoma (LGAL).

MATERIALS AND METHODS

Data of endoscopically obtained duodenal biopsies from 137 cats were evaluated retrospectively. Cytology was performed using the squash smear technique with subsequent Diff Quick® staining. Pathological findings were categorized according to type and grade of the inflammatory infiltrate. Moreover, reports were reviewed with regard to diagnosis of LGAL. Histopathology reports were analysed correspondingly and compared to cytology results. Histopathological samples were further evaluated by immunohistochemistry (IHC) if a diagnosis of LGAL had been expressed.

RESULTS

Squash smear preparation of intestinal biopsies was adequate for cytological examination in >97% of cases. Using histopathology as gold standard, with cytology, a sensitivity and specificity for detection of a pathologic process in feline intestinal biopsies of 68.1% and 70.6% were calculated, respectively. Regarding the detection of lymphoplasmacytic (LPE) and eosinophilic enteritis a statistically significant correlation with histopathology (p<0.05) was observed. With regard to grade of the inflammatory infiltrate, a weak correlation was calculated (r=0.482). Of 21 cats diagnosed or suspected with LGAL by cytology, IHC confirmed nine cases whereas 11 cases were reclassified as LPE. None of the confirmed LGAL had been missed with histopathology. A sensitivity of 60.0% and specificity of 90.6% for cytological detection of feline LGAL was obtained.

CONCLUSION AND CLINICAL RELEVANCE

The sensitivity of cytology to diagnose LGAL is low and it has no additional significance to histological biopsies.

Comparison of auricular and rectal temperature measurement in normothermic, hypothermic, and hyperthermic dogs

OBJECTIVE

Measurement of rectal temperature is the most common method and considered gold standard for obtaining body temperature in dogs. So far, no study has been performed comparing agreement between rectal and auricular measurements in a large case series. The purpose of the study was to assess agreement between rectal and auricular temperature measurement in normothermic, hypothermic, and hyperthermic dogs with consideration of different environmental conditions and ear conformations.

MATERIALS AND METHODS

Reference values for both methods were established using 62 healthy dogs. Three hundred dogs with various diseases (220 normothermic, 32 hypothermic, 48 hyperthermic) were enrolled in this prospective study. Rectal temperature was compared to auricular temperature and differences in agreement with regard to environmental temperature, relative humidity, and different ear conformations (pendulous versus prick ears) were evaluated using Pearson's correlation coefficient and Bland-Altman analysis.

RESULTS

Correlation between rec- tal and auricular temperature was significant (r: 0.892; p  <  0.01). However, Bland-Altman plots showed an inacceptable variation of values (bias: 0.300 °C; limits of agreement: -0.606 to 1.206 °C). This variation was above a maximal clinical tolerance of 0.3 °C, which was established by experts' opinion (n = 16). Relative humidity had a significant influence (p   =   0.001), whereas environmental temperature did not.

CONCLUSION

Variation between the two methods of measuring body temperature was clinically unacceptable.

CLINICAL RELEVANCE

Although measurement of auricular temperature is fast, simple, and well tolerated, this method provides a clinically unacceptable difference to the rectal measurement.

Assessment of cytological criteria for diagnosing osteosarcoma in dogs

OBJECTIVES

To evaluate the specific cytological criteria of osteosarcomas in dogs.

METHODS

Significant cytological characteristics of osteosarcoma and benign mesenchymal bone proliferations were determined from imprint smears of 25 dogs with osteosarcoma (group 1) and 20 dogs admitted for removal of surgical bone implants after uncomplicated healing of bone fractures (group 2).

RESULTS

Mild to moderate cellular necrosis occurred frequently in patients with osteosarcoma. The cytoplasm of osteoblasts was pale blue to blue with a more pronounced basophilia in group 2. In 48 per cent of the patients in group 1, but none in group 2, osteoblasts showed a slight to moderate eosinophilic cytoplasmic granulation. In both groups, osteoblasts contained one red to pale blue nucleus with one or two grey-red to blue nucleoli in group 2. Forty-four per cent of animals in group 1 had osteoblasts with more than two nucleoli per nucleus. The median nuclear:cytoplasmic ratio was higher in group 1 (1:2.0) than in group 2 (1:3.5). Osteoblasts in group I were frequently seen to have a clumped chromatin pattern and showed significantly more criteria of malignancy (median six criteria per patient) than those in group 2 (median two criteria per patient). In group 1, mitoses of osteoblasts were detectable in 23 of 25 dogs, whereas only one dog in group 2 had evidence of mitotic osteoblasts.

CLINICAL SIGNIFICANCE

Cytological criteria can be helpful in the diagnosis of canine osteosarcoma.

The influence of age on the cytology of the liver in healthy dogs

Liver cytology was evaluated in 28 healthy dogs 1-14 years of age with normal liver structure and function. Smears were stained with May-Grünwald-Giemsa. Hepatocytes had distinct cell borders, and cells did not overlap. Cells with two nuclei and cells with intranuclear crystalloid structures were observed regularly. Cytoplasm contained small numbers of vacuoles characteristic of glycogen and lipid and small amounts of pigment consistent with ceroid or bile. Nuclei were uniform. Small numbers of biliary epithelial cells were seen in most samples. Lymphocytes and neutrophils occurred in small numbers, with lipocytes, mast cells, fibrocytes, mesothelial cells, eosinophils, and Kupffer macrophages seen less frequently. Mean parenchymal cell sizes were significantly greater in older dogs, but no age-related differences were observed in nuclear size. Older dogs also had a significantly increased number of nuclei per cell. There were more neutrophils in young and old dogs than in middle-aged dogs.

Assessment of cytological criteria for diagnosing basal cell tumours in the dog and cat

A retrospective study was undertaken in which cytological features of basal cell tumours from 18 dogs and 12 cats were examined. Fine-needle aspiration biopsy was performed for cytological examination and diagnosis was confirmed on histopathological examination of excised tumour specimens. Cytological smears were analysed for occurrence of cystic areas, as well as frequencies of squamous cells, fibrocytes, fibroblasts, neutrophils, lymphocytes, mast cells, melanocytes and basal cells. Basal cell aggregates were examined for indicators of malignancy, evidence of basaloid cell structure, well defined cellular borders and cell aggregation patterns. Cellularity and quality of smears was moderate to good, although, in six aspirates, cellularity was poor due to a high amount of degenerate material within the tumours. Fifteen of the smears revealed between one and three nuclear criteria of malignancy. However, despite the less well differentiated appearance of basal cells that was sometimes seen, the tumours were considered benign based on histopathological examination. Basal cell tumours are therefore likely to be underdiagnosed on cytological examination due to non-specific features. The occurrence of other cell populations and lack of cells with basaloid structures and linear aggregation patterns might further confuse the tumour diagnosis. The authors conclude that the cytological diagnosis of basal cell tumours can be based on the criteria described in the present study.

[Clinical experiences with cytology in the dog]

In a retrospective study (1995) cytological diagnoses of 3987 specimen of different origin in the dog were evaluated. Biopsies were performed at the Department of Clinical Sciences of Companion animals at the University of Utrecht or sent in by external practitioners. Biopsies were obtained from different regions including skin/subcutis, mammary gland, lymph node, external ear canal, kidney, urinary bladder, urethra, prostatic gland, testes, bone, bone marrow, synovia, nose, oral cavity, cerebrospinal fluid, bronchial lavage, lung, spleen, liver, conjunctiva, and retrobulbar region. The majority of biopsies were obtained from skin/subcutis (n = 1815), lymph node (n = 706), and mammary gland (n = 415). A high percentage of non-diagnostic biopsies were observed with biopsies of lung, mammary gland, cerebrospinal fluid, external ear canal, and oral cavity. The frequencies of diagnoses in the different areas will be presented and the diagnostic indications of cytology are discussed.

Feline eosinophilic conjunctivitis

OBJECTIVE

To review 12 cases of histologically confirmed feline eosinophilic conjunctivitis, their clinical, cytologic, histologic and electronmicroscopic findings, results on PCR for FeHV-1, treatment and outcome.

ANIMALS STUDIED

Twelve naturally occurring cases presented during a period of 26 months.

PROCEDURES

Thorough ophthalmologic examination, conjunctival scrapings performed with the cytobrush method; histologic samples from the palpebral conjunctiva; PCR for FeHV-1 on Schirmer Tear Test (STT) strips; saliva and nasal swabs, and retrospective evaluation of all results.

RESULTS

The breed most commonly affected was the Domestic Shorthair (n = 8), followed by Persians (n = 2), Somali (n = 1) and Siamese (n = 1). Age at presentation was 1-15 years with a mean age of 7.2 years. Nine cats were castrated males; three cats were females: two of them were spayed. Unilateral (n = 7) or bilateral (n = 5) involvement with depigmentation and erosions of lid margin, blepharospasm, swelling and redness of conjunctiva and third eyelid were the most common clinical findings. Frequency of eosinophils in cytologic samples was more than 10% in every patient. PCR for FeHV-1 on STT was negative in all cases. Histologically, eosinophils, lymphocytes, plasma cells, mast cells and macrophages were involved. On electronmicroscopy, viral particles were not detected. Ten cases needed long-term anti-inflammatory treatment.

CONCLUSIONS

The 12 reviewed cases suggest that feline eosinophilic conjunctivitis is a chronic inflammatory uni- or bilateral disease of the adult cat. Typically the lid margin was also involved, and was thickened, depigmented and erosive. Cytological examination of conjunctival scrapings was a valuable tool for detecting eosinophilic conjunctivitis. The cytological findings correlated well with the histopathological findings in our patients. Topical or systemic anti-inflammatory drugs resolved the clinical symptoms in our cases within a short period of time. Neither electronmicroscopy nor PCR were able to detect involvement of FHV1 in the represented cases. The etiopathogenic role of FeHV-1 remains undetermined.

Correlation of haemostatic abnormalities with tumour stage and characteristics in dogs with mammary carcinoma

Sixty female dogs with untreated mammary carcinoma, comprising equal numbers of dogs in tumour stages I to IV, were evaluated for haemostatic abnormalities using the following tests: platelet count, prothrombin time, activated partial thromboplastin time, thrombin time, plasma activity of factor V, VIII and X, plasma concentration of fibrinogen, fibrin monomers and fibrinogen degradation products, and plasma antithrombin III activity. Two-thirds of all dogs had one or more haemostatic test abnormality of which the likelihood and frequency was increased in those with stage III and IV neoplasia. Haemostatic abnormalities were more frequently observed in dogs which had mammary tumours with distant metastases, extended tumour necrosis, inflammatory carcinomas, tumours fixed to underlying structures, or tumours in which there was penetration of the tumour capsule by tumour cells. As in humans with mammary carcinoma, these haemostatic abnormalities might be used as prognostic indicators, but their clinical importance remains unknown.

Haemophagocytic syndrome with disseminated intravascular coagulation in a dog

Clinical signs and haematological abnormalities of haemophagocytic syndrome of unknown origin are described for a male, nine-year-old rottweiler referred because of weakness, depression, mild weight loss and relapsing fever. Mucous membranes were pale and the spleen was enlarged. Ultrasonography revealed diffuse irregular structures in the enlarged spleen, and cytological examination of multiple fine needle aspirates of the spleen demonstrated extramedullary haematopoiesis. Haematological examination revealed pancytopenia and disseminated intravascular coagulation. A bone marrow smear contained numerous marrow macrophages with a cytologically benign appearance, containing phagocytosed haematopoietic cells. The dog died one week after referral. The differential diagnosis is discussed.