Eosinophilic papulocrustous dermatitis (miliary dermatitis) and eosinophilic inflammatory bowel disease in two cats

Two cats with chronic eosinophilic skin disease were investigated. The clinical investigation of the skin disease in one cat was limited and inflammatory bowel disease was diagnosed post mortem. A history of weight loss and a palpably thickened bowel in the second cat suggested concurrent gastrointestinal disease. Diagnosis of inflammatory bowel disease was confirmed on biopsy. Treatment with azathioprine and methylprednisolone acetate resolved the signs of gastrointestinal disease, the pruritus and 95% of the skin lesions. The concurrence of eosinophilic papulocrustous dermatitis and eosinophilic bowel disease raises the possibility of their being linked bv a common aetiology or pathophysiology.     

Correlation of rhinoscopic signs of inflammation with histologic findings in nasal biopsy specimens of cats with or without upper respiratory tract disease

OBJECTIVE: To investigate the correlation of cumulative rhinoscopic findings of hyperemia, mucus accumulation, and turbinate destruction with the type and severity of inflammatory infiltrates in nasal biopsy specimens of cats with or without upper respiratory tract disease. DESIGN: Prospective study. ANIMALS: Cats with (n = 11) and without (6) upper respiratory tract disease and cats with unknown medical histories (27). PROCEDURES; Lesions of hyperemia, mucus accumulation, and turbinate destruction detected rhinoscopically were each scored (scale, 0 [absent] to 3 [severe]), and a cumulative rhinoscopic score for each nasal cavity was calculated. Fifty biopsy specimens were examined histologically, and inflammatory infiltrates (lymphoplasmacytic or neutrophilic) were graded as absent, mild, moderate, or severe. Cumulative rhinoscopic scores and inflammation grades were compared for each specimen-cavity combination. RESULTS: In cats of known disease status, there was a positive but weak correlation between cumulative rhinoscopic scores and inflammation grades in biopsy specimens. In cats of unknown disease status, there was no similar correlation. Biopsy specimens with minimal inflammation were commonly obtained from nasal cavities with low rhinoscopic scores; specimens with moderate or severe inflammatory changes were frequently obtained from cavities that appeared normal rhinoscopically. Type of inflammatory infiltrates was not correlated with rhinoscopic signs of inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: The correlation of rhinoscopic findings with inflammation severity in nasal biopsy specimens (determined histologically) was weak or lacking in cats of known and unknown disease status, respectively. Results indicated that rhinoscopy with biopsy provides more complete evaluation of nasal disease than rhinoscopy alone in cats.     

Correlation of cytologic and histopathologic findings with perinodal echogenicity of abdominal lymph nodes in dogs and cats

Abdominal lymphadenopathy in dogs and cats is routinely investigated with ultrasound. As the determination between benign and neoplastic etiologies of lymphadenopathy affects patient management, specific sonographic characteristics associated with both benign and neoplastic lymph nodes have been suggested. However, a significant overlap between these characteristics exists, necessitating a cytologic or histopathologic diagnosis in most instances. The objectives of this retrospective, cross‐sectional study were to evaluate whether echogenicity of perinodal fat could be a discriminator between benign and neoplastic abdominal lymphadenopathy and to assess if additional sonographic features associated with malignancy could be identified in lymph nodes with hyperechoic perinodal fat. Small animal patients (257 dogs and 117 cats) with sonographic evidence of abdominal lymphadenopathy and a cytological or histopathological diagnosis were evaluated for differences in the proportions of sonographic features between benign and neoplastic groups. Greater maximum long axis diameter (in dogs and cats) and a greater number of abnormal lymph nodes (in cats) were associated with malignancy in lymph nodes with hyperechoic perinodal fat. Canine lymph nodes with round cell neoplasia were significantly more likely to have hyperechoic perinodal fat. Lymph nodes affected with other neoplasia or with lymphadenitis were equally likely to have normal or hyperechoic perinodal fat. Reactive lymph nodes were significantly less likely to have hyperechoic perinodal fat in both species. These results suggest that though echogenicity of perinodal fat is a nonspecific finding, abdominal lymph nodes with hyperechoic perinodal fat are less likely to be reactive and sampling of these lymph nodes may be indicated.     

Clinicopathologic, histologic, and toxicologic findings in 70 cats inadvertently exposed to pet food contaminated with melamine and cyanuric acid

OBJECTIVE: To document clinicopathologic, histologic, and toxicologic findings in cats inadvertently exposed to pet food contaminated with melamine and cyanuric acid. DESIGN: Case series. ANIMALS: 70 cats from a single cattery inadvertently fed contaminated food that was the subject of a March 2007 recall. PROCEDURES: Clinical signs, clinicopathologic and histopathologic findings, and results of toxicologic analyses were recorded. RESULTS: Clinical signs were identified in 43 cats and included inappetence, vomiting, polyuria, polydipsia, and lethargy. Azotemia was documented in 38 of the 68 cats for which serum biochemical analyses were performed 7 to 11 days after consumption of the contaminated food. One cat died, and 13 were euthanized. Histologic examination of kidney specimens from 13 cats revealed intratubular crystalluria, tubular necrosis with regeneration, and subcapsular perivascular inflammation characterized by perivascular fibroplasia or fibrosis and inflammation with intravascular fibrin thrombi. Toxicologic analyses revealed melamine and cyanuric acid in samples of cat food, vomitus, urine, and kidneys. CONCLUSIONS AND CLINICAL RELEVANCE: In cats unintentionally fed pet food contaminated with melamine and cyanuric acid, the most consistent clinical and pathologic abnormalities were associated with the urinary tract, specifically tubular necrosis and crystalluria.     

Thymoma-associated exfoliative dermatitis in cats

Five cases of exfoliative dermatitis in cats were presented from 1996 to 2002 in which a feline thymoma was found by postmortem or postsurgical examination. Besides abundant exfoliation of keratin squames and layers, the histologic picture of the skin revealed a similar pattern of interface dermatitis with predominantly CD3+ lymphocytes and fewer mast cells and plasma cells. In the epidermal basal layer a hydropic degeneration of keratinocytes was present. In all cases an infundibular lymphocytic mural folliculitis and absence of or drastic decrease in the number of sebaceous glands occurred. In addition to the so far described cell-poor type, we also found examples of a cell-rich skin lesion. Together with the clinical observation of generalized exfoliative dermatitis, the histologic pattern of this dermatitis was suggestive of an underlying thymoma. The pathogenesis of this skin disease in association with thymic neoplasia remains obscure, and our results contradict the hypothesis of production of autoantibodies that cross-react with epithelial antigens. The morphology of the thymomas and CD3 expression of the thymocytes varied and did not seem to have an impact on the dermal lesions.     

Echocardiographic findings in 103 cats with hyperthyroidism

Using M-mode echocardiography, cardiac abnormalities were studied in 103 cats with untreated hyperthyroidism. In addition, follow-up echocardiography was performed on 24 of these cats to assess the long-term (4 to 21 months) effect of treatment (thyroidectomy or radioiodine) on thyrotoxic cardiac disease. The most common echocardiographic abnormality in the 103 untreated hyperthyroid cats was hypertrophy of the left ventricular caudal wall (71.9%). Hypertrophy of the interventricular septum also was documented in 39.8% of the 103 cats. Other abnormalities included high values for left atrial diameter (70.0%), aortic root diameter (18.5%), and left ventricular diameter at end diastole (45.6%). In some of these cats, indices of contractility were enhanced; in 21.4% and 14.6% of the cats, values for shortening fraction and velocity of circumferential fiber shortening, respectively, were greater than those values measured in clinically normal cats. After treatment of the hyperthyroidism, left ventricular hypertrophy resolved or improved in many of the cats, as indicated by decreases in left ventricular caudal wall and interventricular septum thicknesses. Hyperdynamic wall motion resolved in all cats after treatment, as evidenced by consistent decreases in shortening fraction and velocity of circumferential fiber shortening. Despite these improvements, some cats had one or more persistently abnormal echocardiographic values after treatment. These results suggested that in cats, hyperthyroidism commonly is associated with largely reversible cardiomyopathy. In those cats in which cardiomyopathy persists or worsens after treatment, underlying primary cardiomyopathy or thyroid hormone-induced cardiac structural damage may exist.     

Radiographic findings in cats with mycobacterial infections

This study describes radiographic changes associated with mycobacterial infection in 33 domestic cats confirmed by culture or interferon-gamma testing. Infection was seen most frequently in adult (average age 5.7 years; range 1.5-12 years), non-pedigree (87%; 27/31), neutered male cats (69%; 22/32). The most common infections were Mycobacterium microti (60%; 18/30) and Mycobacterium bovis (37%; 11/30); Mycobacterium avium and Mycobacterium malmoense were infrequently cultured (3% of each; 1/30). Radiographs were available for the thorax (24 cats), abdomen (eight), appendicular skeleton (11) and head (three). Radiographic changes affected the thorax most commonly, consisting of bronchial (46%; 11/24), alveolar (38%; 9/24), nodular unstructured interstitial (38%; 9/24) or unstructured interstitial (25%; 6/24) lung patterns, which were often mixed. Perihilar or sternal lymphadenopathy were common (42%; 10/24), particularly perihilar lymphadenopathy (25%; 6/24). Skeletal changes were found in the distal antebrachium (three), pes (two), maxilla, scapula, spine, manus, femur, and tarsus (one each). Changes were typically osteolytic (73%; 8/11), often permeative osteolytic (64%; 7/11). Osteoproliferative changes were seen in three cats and soft tissue swelling in five cats, which were adjacent to the bony abnormality in four cats. Other changes included submandibular soft tissue swelling, marked aortic, aortic root and brachiocephalic trunk calcification, and soft tissue swelling with calcification in the distal antebranchium which was not involving bone. Abdominal changes were uncommon (seen in 2/8 cats) and consisted of hepatomegaly and hepatosplenomegaly. In summary, radiographic changes were varied, no lesion was pathognomic for mycobacterial infection, and pathology was seen most commonly in the thorax.     

Management of feline miliary dermatitis by supplementing the diet with essential fatty acids

Of eight cats with miliary dermatitis, six showed a good response to treatment with a dietary supplement of essential fatty acids. The analysis of serum fatty acids revealed significant abnormalities in cats with miliary dermatitis compared with normal cats.     

Clinical findings in dogs and cats with lead poisoning

Over an 11-year period, 68 cases of lead poisoning were diagnosed in dogs and three in cats, accounting for 58.6% and 21.4% of the accidental poisonings in dogs and cats, respectively, presented at the Small Animal Clinic, University of Queensland. Of the dogs, 94% showed alimentary tract involvement and 67.6% central nervous system signs. Blood lead concentrations above 0.3 ppm were considered to indicate toxicity when associated with alimentary tract or central nervous system abnormalities. The percutaneous absorption of lead in dogs is proposed as a factor for intoxication.     

Cytogenetic and histologic examination of four tortoiseshell cats

Tortoiseshell colored tomcats are very uncommon. In most cases their phenotype is caused by an aberration of sex chromosomes. In this study, we carried out cytogenetic investigations in four tortoiseshell tomacats. In two cases, an XXY syndrome could be proven. Another tortoiseshell tomcat had an XX/XY chromosomal constitution. One tomcat showed an exclusively male XY karyotype. In two cases the testes were histologically examined. In one XXY phenotypically male cat there was no spermatogenesis present. In the tomcat with XX/XY-chimerism spermatogenesis was seen in some testicular tubules.     

Evaluation of skin test reactivity to environmental allergens in healthy cats and cats with atopic dermatitis

OBJECTIVE: To evaluate skin test reactivity to environmental allergens in healthy cats and in cats with atopic dermatitis (AD). ANIMAL: 10 healthy cats and 10 cats with AD. PROCEDURE: 10 allergens in serial dilutions were injected ID on the lateral aspect of the thorax of sedated cats. Histamine (0.01% solution) and buffer solutions were used as positive and negative controls, respectively. Immediately after the last injection, 10% fluorescein solution was administered IV. Skin test results were evaluated with ultraviolet light after 15 to 30 minutes and at 4 and 6 hours by 2 independent observers. In the control group, skin tests were repeated after 6 weeks. Skin test reactivity and the nature of the immunoglobulin involved were investigated by use of the Prausnitz-Küstner test with untreated and heat-treated cat sera. RESULTS: Intertest and interobserver agreement were high when measurement of the diameter of the fluorescent wheal was used to evaluate skin test responses, compared with assessment of its intensity. In both groups of cats, immediate skin test reactivity was observed as an IgE-mediated reaction, as an IgG-mediated reaction, and as a result of nonspecific mast cell degranulation. There was no correlation between allergen concentration and the type of reaction observed. CONCLUSIONS AND CLINICAL RELEVANCE: Skin test reactivity in cats should be evaluated after IV administration of 10% fluorescein solution by means of a Prausnitz-Küstner test to differentiate among IgE-mediated, IgG-mediated, and nonspecific reactions.     

A seasonal eosinophilic dermatitis in cats

Twenty cats from Nelson with distinctive crusting and erosive dermatitis of the nasal bridge and histological lesions of eosinophilic dermatitis, often with collagenolysis, were examined in 1990 and 1991. Four of the cats also had pinnal dermatitis and five had eruptive lesions on the chin. The condition was intermittent and seasonal, occurring in summer and autumn. It is probable that the lesions were caused by hypersensitivity to insect bites, as has been demonstrated in a similar clinicopathological syndrome recently recognised in Australia.     

Haematological and biochemical findings in cats in Australia with lymphosarcoma

OBJECTIVE: To describe, for the first time, haematological and serum biochemical findings in cases of lymphosarcoma in Australian cats. DESIGN: A prospective multi-institutional study. PROCEDURE: Of 118 affected cats presented to the authors over a 18-month period, 97 were evaluated haematologically and 87 biochemically. Haematological analysis usually included determination of packed cell volume, haemoglobin concentration, red blood cell and leukocyte counts, differential leukcocyte count, reticulocyte count and examination of buffycoat smears for neoplastic cells. Serum biochemical analysis was done primarily with a discrete analyser and included a panel of commonly used analytes. RESULTS: Nonregenerative anaemia was present in 54% (52/97) of cats. Neutrophilia, present in 65% (59/91) of cats, was commonly associated with lymphocytopaenia, eosinopaenia and monocytosis. Of the 13 cats with a secondary leukaemic manifestation, only five had distinct lymphocytosis. Serum biochemical abnormalities either were nonspecific, such as hypoglycaemia in 37% (32/87) of cats, or related to specific tissue involvement, such as hypoalbuminaemia in 76% (31/41) of cats with alimentary involvement and azotaemia in 60% (15/25) of cats with renal involvement. CONCLUSION: It was shown for the first time that haematological and serum biochemical findings are of limited value in diagnosing lymphosarcoma in Australian cats, except if they are leukaemic. Although clinical pathological changes were common, they were nonspecific or related to specific tissue involvement. Their value in assessing response to therapy needs to be examined further. Patient characteristics such as age, breed and sex also had limited effect on laboratory findings and those observed were of little consequence. Additionally, histological and immunophenotypical variations in tumour type had little effect on laboratory findings.     

Clinicopathological findings in five cats with paw calcification

This retrospective study describes the clinicopathological findings in five cats with soft tissue mineralisation of interdigital spaces and footpads. Paw disease was the reason for veterinary consultation in three out of five cats. All cats had laboratory findings suggestive of renal failure and high solubility product [calciumxphosphorus]. In all cases, cytological examination of paw lesions was suggestive of calcinosis. The results of our study agree with two previous case reports of paw calcification in the cat, suggesting a metastatic pathogenesis and a correlation between paw mineralisation and renal failure.     

Adverse events in 50 cats with allergic dermatitis receiving ciclosporin

Ciclosporin is an immunosuppressive drug that has been used to treat allergies and other immune-mediated diseases in cats, dogs and humans. Information about the adverse effects of ciclosporin in cats has been limited to smaller studies and case reports. Adverse effects in dogs are mainly gastrointestinal in nature, but humans can also experience hypertension and altered renal function. The aim of this retrospective case series study was to document the occurrence and clinical appearance of adverse events in cats receiving ciclosporin to treat allergic skin disease. The medical records of 50 cats with allergic dermatitis treated with oral ciclosporin (1.9-7.3 mg/kg/day) were reviewed. Adverse events occurred in 66% (33 cats). Adverse events likely to be associated with ciclosporin included the following: vomiting or diarrhoea within 1-8 weeks of receiving ciclosporin (24%), weight loss (16%), anorexia and subsequent hepatic lipidosis (2%) and gingival hyperplasia (2%). Other adverse events less likely to be associated with ciclosporin therapy included the following: weight gain (14%), dental tartar and gingivitis (10%), otitis (4%), chronic diarrhoea (4%), inflammatory bowel disease with indolent gastrointestinal lymphoma (2%), urinary tract infection (2%), cataract (2%), elevated liver enzymes (2%), hyperthyroidism and renal failure (2%) and transient inappropriate urination (2%). Some cats experienced multiple adverse events. Case-control studies are needed to prove cause and effect of ciclosporin with regard to these adverse events.     

Clinical findings in cats with dilated cardiomyopathy and relationship of findings to taurine deficiency.

Between October 1986 and September 1988, 37 cats with moderate to severe idiopathic myocardial failure (dilated cardiomyopathy) were evaluated prospectively. Low plasma taurine concentration and diet history including foods that can cause taurine deficiency were documented in most of the cats. Comparison with a retrospectively studied population of 33 cats with dilated cardiomyopathy diagnosed between 1980 and 1986 demonstrated that the clinical and historical findings in the 33 retrospectively studied cats were similar to those in the 37 cats studied prospectively. Clinical findings in the 2 groups were also similar to findings previously reported in the literature. Because clinical findings and diet history were similar in the prospective and retrospective groups, we believe that many cats in the latter group had diet-induced taurine deficiency. These findings support the conclusion that most cases of dilated cardiomyopathy in cats have a common etiopathogenesis related to diet and as such are preventable.