Nucleated erythrocytes in blood smears of dogs undergoing chemotherapy

The frequency of normoblastemia in dogs receiving chemotherapy is unknown. To provide this information, we calculated the percentage and number of nucleated erythrocytes (nRBCs) in blood of dogs treated for lymphoma (n = 284), mast cell tumour (n = 40) or carcinoma (n = 46). Relative normoblastemia (>1 or >5%) and absolute normoblastemia (>0.1 or >0.4 × 10³ µL^?1) were found after administration of vincristine (49.3, 20.5, 42.5, 19.2%, respectively), carboplatin (37.0, 2.2, 34.8, 13.0%), cyclophosphamide (30.8, 7.7, 23.1, 7.7%), doxorubicin (25.0, 8.3, 21.7, 6.7%), vinblastine and prednisone (25.0; 5.0; 22.5; 7.5%). Absolute normoblastemia was very severe (>1.0 × 10³ nRBC µL^?1) after administration of vincristine (9.6%), doxorubicin (3.3%), vinblastine and prednisone (2.5%). Absolute normoblastemia negatively correlated with RBC counts (P < 0.001) and positively (P < 0.001) with reticulocyte and WBC counts, but correlation coefficients were low (?0.19, 0.37, 0.15). Vincristine, doxorubicin or vinblastine and prednisone may induce severe normoblastemia. This may increase WBC counts and mask neutropenia associated with chemotherapy.     

Third-degree atrioventricular block in 21 cats (1997-2004)

The effect of 3rd-degree atrioventricular block on long-term outcome in cats is unknown. Clinical findings and long-term outcome of 21 cats with 3rd-degree atrioventricular block were studied retrospectively. Median age of cats studied was 14 years (range 7-19 years). Presenting signs included respiratory distress or collapse, but 6 cats had no clinical signs of disease. Eight cats had congestive heart failure (CHF) at the time that 3rd-degree atrioventricular block was detected. Heart rates ranged from 80 to 140 beats per minute (bpm; median 120 bpm) with no difference in heart rate between cats with and those without CHF. Eleven of 18 cats that had echocardiograms had structural cardiac disease, and 6 cats had cardiac changes consistent with concurrent systemic disease. No atrioventricular nodal lesions were detected by echocardiography. One cat had atrioventricular nodal lesions detected on histologic examination. Median survival of 14 cats that died or were euthanized was 386 days (range 1-2,013 days). Survival did not differ between cats with or without CHF or between cats with or without structural cardiac disease. Thirteen cats with 3rd-degree atrioventricular block survived > 1 year after diagnosis, regardless of presenting signs or underlying cardiac disease. Third-degree heart block in cats is often not immediately life threatening. Survival was not affected by the presence of underlying heart disease or congestive heart failure at the time of presentation. Even cats with collapse might survive > 1 year without pacemaker implantation.     

Clinical and pathologic features of endometrial hyperplasia, pyometra, and endometritis in cats: 79 cases (1980-1985)

Records of 79 cats determined to have endometrial hyperplasia (EH) with or without pyometra or endometritis were studied. Forty-eight cats (61%) were spayed or died because of complications relating to reproductive tract disease. All other cats were free of clinical signs of disease, and lesions were found incidentally during routine ovariohysterectomy or at necropsy. Prevalence of uterine lesions was greater in cats greater than or equal to 5 years old. Breeding, age at first breeding, and queening could not be correlated with clinical or pathologic signs of disease. Seventy-one percent (34/48) of cats with clinical signs referable to the reproductive tract had histologic evidence of pyometra or endometritis, whereas only 19% (6/31) of cats without clinical signs had histologic evidence of either disease. Only 23% (9/39) of cats without pyometra or endometritis had corpora lutea (CL) in at least one ovary, whereas 40% (16/40) of cats with either pyometra or endometritis had CL. We concluded that the prevalence of EH in cats increases with age in sexually intact female cats, and that most cases of pyometra or endometritis, but not EH, in cats are associated with retained CL.     

Prevalence of serum antibodies against Bartonella species in the serum of cats with or without uveitis

Bartonella henselae has been implicated as a causative agent of chronic uveitis in people and in some cats. The objective of this study was to determine whether Bartonella species seroprevalence or titer magnitude varies among cats with uveitis, cats without ocular diseases recorded and healthy cats, while controlling for age and risk of flea exposure based on state of residence. There was no difference in seroprevalence rates or titer magnitude between cats with uveitis and cats with non-ocular diseases. Healthy cats were more likely to be seropositive for Bartonella species than cats with uveitis. The median Bartonella species titer was 1:64 for all groups, although healthy cats were more likely to have higher titers than cats with uveitis and cats with non-ocular disease. The results suggest that serum antibody tests alone cannot be used to document clinical uveitis associated with Bartonella species infection.     

Prevalence and risk factors for heartworm infection in cats from northern Florida

Necropsies were performed on 630 adult cats in northern Florida to determine the prevalence and risk factors for heartworm infection in cats of this region. Heartworms were identified in 4.9% of cats, and serological evidence of heartworm exposure was present in 17% of cats. Not all cats from which heartworms were recovered were seropositive for heartworm antigen or antibody. There was no association between heartworm infection and co-infection with feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV). Male cats were at higher risk of infection with heartworm, FeLV, or FIV than were females. Because even a single heartworm can cause clinical disease or death in cats, the authors conclude that cats in this region should receive heartworm prophylaxis to prevent heartworm infection.     

Treatment of fibroadenomatous hyperplasia in cats with aglépristone

Fibroadenomatous hyperplasia (FAH) is characterized by a rapid proliferation of mammary stroma and duct epithelium of 1 or more glands and predominantly affects younger female cats. Endogenous progesterone and exogenous progestogens play an important role in the genesis of FAH. The presence of progesterone receptors in fibroadenomatous tissue allows for targeted endocrine therapy with progesterone receptor blockers. We report on 22 young cats with FAH, none of which had responded to the withdrawal of progestogens or ovariectomy. The common signs were tachycardia (11 cats); skin ulceration, painful mammary glands, or both (16 cats); lethargy (8 cats); and anorexia (4 cats). The cats were treated with subcutaneous injections of the progesterone receptor blocker aglépristone on 1 (7 cats, 20 mg/kg) or 2 consecutive days (15 cats, 10 mg/kg/d) once weekly. All but 1 cat responded with a complete and lasting remission of signs after 1-4 weeks of treatment. Two cats had a short-term skin irritation at the site of the aglépristone injection. Two pregnant cats with FAH aborted after treatment with aglépristone and subsequently developed endometritis. In conclusion, the results of this study demonstrate that FAH in cats can be treated successfully with the progesterone receptor blocker aglépristone.     

Feline epitheliotropic intestinal malignant lymphoma: 10 cases (1997-2000)

The clinical, histopathologic, and immunohistochemical features of 10 cats with epitheliotropic intestinal malignant lymphoma (EIL) are described. Intestinal biopsy samples were reviewed by 3 pathologists to confirm the diagnosis of EIL. These samples (n = 10) were compared to the intestinal biopsies of normal cats (n = 11), cats with inflammatory bowel disease (IBD; n = 7), and cats with non-EIL (n = 9) for quantification and immunophenotyping of intraepithelial lymphocytes. Immunophenotypic studies were performed with CD3 and CD79a antibody stains to assess for T- and B-cell immunoreactivity, respectively. EIL biopsies had markedly more intraepithelial lymphocytes than normal intestine (NRL) and samples from cats with IBD. However, no marked difference was observed in the number of intraepithelial lymphocytes in cats with non-EIL compared to cats with EIL. Regardless of the histologic diagnosis, the intraepithelial lymphocytes in all cats were small- to intermediate-sized T cells. Clinical findings and imaging studies in the cats identified minimal or nonspecific findings in affected cats. Most cats fit the typical profile of cats with IBD or alimentary malignant lymphoma. Nine of 10 cats with EIL were treated with prednisone with or without additional chemotherapy. Four cats were refractory to chemotherapy and were euthanized within 3.5 months. The remaining 5 cats had long-term survival times of 11 months or greater. The median survival time was 11 months. Additional studies are warranted to better characterize EIL and its relationship to IBD in cats and non-EIL and to identify optimal treatment strategies for this disease.     

Plasma Taurine Concentrations and M-mode Echocardiographic Measures in Healthy Cats and in Cats with Dilated Cardiomyopathy

M-mode echocardiography was completed and plasma taurine concentrations were determined in 79 healthy cats and 77 cats with dilated cardiomyopathy (DCM). In healthy cats, a relationship was not observed between plasma taurine concentrations and any M-mode echocardiographic measurement. End-systolic and end-diastolic cardiac chamber dimensions were larger; wall thickness measures were smaller; and calculations of fractional shortening were less in cats with DCM than in healthy cats. Plasma taurine concentrations less than 30 nmol/mL were detected in 7/79 healthy cats and in 52/77 cats with DCM. Of the 52 cats with DCM and an initial plasma taurine concentration less than 30 nmol/mL, 23 died or were euthanized during the first post-treatment week, 7 were lost to further study, and 22 improved after taurine supplementation. Of the 25 cats with DCM and an initial plasma taurine concentration greater than or equal to 30 nmol/mL, 9 died or were euthanatized during the first post-treatment week, and 9 were lost to further study. Two cats did not improve, of which one died and one was euthanatized 4 to 8 weeks after initiation of taurine supplementation. Five cats with a plasma taurine concentration greater than or equal to 30 nmol/mL improved after taurine supplementation. Myocardial function subsequently deteriorated in three of these cats. Two of the three cats had signs of congestive heart failure redevelop.     

Prevalence of pituitary tumors among diabetic cats with insulin resistance

OBJECTIVE: To determine prevalence of pituitary tumors, detectable by means of computed tomography or magnetic resonance imaging, in cats with insulin resistance suspected to have acromegaly or hyperadrenocorticism versus cats with well-controlled diabetes mellitus. DESIGN: Case series. ANIMALS: 16 cats with insulin resistance that were also suspected to have acromegaly (n = 12) or pituitary-dependent hyperadrenocorticism (4) and 8 cats with well-controlled diabetes mellitus. PROCEDURE: Computed tomography was performed on all 16 cats with insulin resistance and 2 cats in which diabetes mellitus was well-controlled. The remaining 6 cats in which diabetes mellitus was well-controlled underwent magnetic resonance imaging. Images were obtained before and immediately after i.v. administration of contrast medium. RESULTS: Computed tomography revealed a mass in the region of the pituitary gland in all 16 cats with insulin resistance. Maximum width of the masses ranged from 4.4 to 12.7 mm; maximum height ranged from 3.1 to 12.6 mm. Results of computed tomography performed on 2 cats with well-controlled diabetes and magnetic resonance imaging performed on the remaining 6 cats were considered normal. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that cats with insulin resistance suspected to have acromegaly or pituitary-dependent hyperadrenocorticism are likely to have a pituitary mass detectable by means of computed tomography or magnetic resonance imaging.     

Prevalence of infectious diseases in feral cats in Northern Florida

Objectives of this study were to determine prevalence of infection in feral cats in Northern Florida with a select group of infectious organisms and to determine risk factors for infection. Blood samples or sera from 553 cats were tested with a panel of antibody, antigen or PCR assays. Male cats were at higher risk for FIV, Mycoplasma haemofelis, and M. haemominutum. Infection with either FeLV or FIV was associated with increased risk for coinfection with the other retrovirus, M. haemofelis, or M. haemominutum. Bartonella henselae had the highest prevalence and was the only organism that did not have any associated risk for coinfection with other organisms. Feral cats in this study had similar or lower prevalence rates of infections than those published for pet cats in the United States. Thus, feral cats assessed in this study appear to be of no greater risk to human beings or other cats than pet cats.     

Study of feline leukemia virus immunity.

Fifteen specific-pathogen-free cats were experimentally infected with FeLV; 8 cats recovered after transient or nondetectable viremia, and 7 cats became persistently viremic. Four additional cats served as noninfected controls. Antibodies to whole FeLV (ELISA and immunoblot [western] analysis), antibodies to fixed FeLV-infected cells, and virus-neutralizing antibodies were monitored for as long as 3 years after infection. As a group, cats that recovered after acute infection developed higher titer of these various antibodies than did cats that became persistently viremic. However, specific combination or titer of antibodies was not always found in recovered cats or in persistently viremic cats. Six cats that had recovered from acute FeLV infection nearly 3 years earlier were reinfected with the same virus. Three of the cats appeared to be resistant to reinfection, 2 cats became transiently viremic, and 1 cat became persistently viremic. Slight and transient anamnestic ELISA-detectable antibody response to whole virus was seen after reinfection; immunofluorescence- and western blot-detectable responses were not greatly enhanced. Five FeLV-recovered cats were monitored for 2 years; FeLV infection spontaneously recurred in 1 cat.     

Bartonella spp antibodies and DNA in aqueous humour of cats.

Bartonella spp antibodies were measured in the serum and aqueous humour of cats with and without uveitis and polymerase chain reaction (PCR) for Bartonella spp DNA was performed on aqueous humour from most of the cats. Serum and aqueous humour were assayed from 49 client-owned cats with uveitis, 49 healthy shelter cats, and nine cats experimentally inoculated with either B henselae or B clarridgeiae, 454 days after inoculation. An aqueous antibody coefficient (C value) was calculated for cats positive for Bartonella spp antibodies in the aqueous humour. Ocular production of Bartonella spp IgG (C value >1) was detected in seven of 49 cats with uveitis, none of 49 healthy shelter cats, and four of nine experimentally inoculated cats. The organism was detected by PCR in the aqueous humour of three of 24 cats with uveitis, one of 49 healthy shelter cats, and four of nine experimentally inoculated cats. Bartonella spp infect the eyes of some cats following natural exposure or experimental inoculation and may cause uveitis in some cats.     

Metabolic and hormonal alterations in cats with hepatic lipidosis

Hepatic lipidosis in cats is a commonly diagnosed hepatobiliary disease of unknown cause. The purpose of this prospective study was to characterize the blood hormone and lipid status of cats with hepatic lipidosis, and to compare this status to that of cats with other types of liver disease and to control cats. Twenty-three cats with hepatic disease were assigned to 1 of 2 groups on the basis of cytopathologic or histopathologic examination of the liver: group 1, hepatic lipidosis (n = 18); or group 2, cholangiohepatitis (n = 5). Ten healthy young adult cats were used as controls. Food was withheld from control animals for 24 hours before blood collection. Concentrations of plasma glucagon and serum insulin, cortisol, thyroxine, triglycerides, cholesterol, phospholipids, and nonesterified fatty acids (NEFAs) were determined in all cats, in addition to routine hematologic and serum biochemical testing. Cats with hepatic lipidosis had higher serum NEFA concentrations than cats with cholangiohepatitis or control cats (P < .05). Cats with cholangiohepatitis had higher serum cholesterol and phospholipid concentrations than those of cats with lipidosis or control cats (P < .05); their plasma glucagon concentrations were higher than those of control cats (P < .05), but were not different from those of cats with hepatic lipidosis. Serum insulin concentrations were significantly higher in control cats than in diseased cats (P < .05), but neither serum insulin nor the insulin to glucagon ratio was significantly different among the cats with hepatic disease. The high concentration of NEFAs in cats with hepatic lipidosis suggests that at least 1 factor in the pathogenesis of this syndrome may involve the regulation of hormone-sensitive lipase.     

Clinical features of salmonellosis in cats: six cases (1981-1986)

Of 6 cats with salmonellosis, only cats 1, 4, and 5 manifested clinical signs of gastroenteritis. In cats 2 to 5, salmonellosis was characterized by fever, a left-shifted leukogram, and vague nonspecific signs of illness. Salmonellae were isolated from blood and feces of cats 1 to 4, and from extraintestinal sites as part of a mixed gram-negative bacterial flora in cats 5 and 6. Of 4 cats with Salmonella bacteremia, cats 2, 3, and 4 were successfully treated with trimethoprim-sulfadiazine, amoxicillin, and/or chloramphenicol; treatment with cephapirin was ineffective in 3 cats. In some cats, salmonellosis was observed as a chronic febrile illness without specific gastrointestinal signs or as a localized tissue infection.     

Seroprevalences of feline leukemia virus and feline immunodeficiency virus in cats with abscesses or bite wounds and rate of veterinarian compliance with current guidelines for retrovirus testing

OBJECTIVE: To determine the seroprevalences of and seroconversion rates for FeLV and FIV infection in cats treated for bite wounds and cutaneous abscesses and to evaluate compliance with recommendations to determine the retrovirus infection status of cats at acquisition and 60 days after a high-risk event. DESIGN: Prospective study. ANIMALS: 967 cats from 134 veterinary practices in 30 states. PROCEDURES: Cats with bite wounds or abscesses were evaluated by use of a point-of-care immunoassay for blood-borne FeLV antigen and FIV antibody. Veterinarians were asked to retest cats approximately 60 days later to determine whether seronegative cats had seroconverted after injury. RESULTS: The combined FeLV-FIV status of only 96 (9.9%) cats was known prior to wound treatment. At the time of treatment, 187 (19.3%) cats were seropositive for 1 or both viruses. Age (adult), sex (male), history of cutaneous wounds, and outdoor access were significantly associated with seropositivity. At 73 of 134 (54.5%) veterinary practices, retesting of cats for retrovirus infection status was recommended to owners of 478 cats. Only 64 (13.4%) cats were retested; of these, 3 of 58 (5.2%) cats that were initially seronegative for FIV antibody seroconverted. CONCLUSIONS AND CLINICAL RELEVANCE: A high proportion of cats with abscesses or bite wounds were seropositive for FeLV antigen or FIV antibody. Compliance with recommendations to test cats for retrovirus infection status at acquisition or after treatment for injury was low. The FeLV-FIV infection status of cats with potential fight wounds should be determined at time of treatment and again 60 days later.     

Effects of body position and ventilation/compression ratios during cardiopulmonary resuscitation in cats

Eighteen cats were anesthetized and were randomly assigned to 2 groups (9 cats/group). Cardiopulmonary resuscitation (CPR) was performed on each cat, with the cat in dorsal (group 1) or lateral (group 2) recumbency, by administering 5 external cardiac compressions/1 interposed (diastolic) ventilation (American Heart Association [AHA] technique; n = 3 cats/technique), simultaneous compression and ventilation (SCV; n = 3 cats/technique), or SCV with 1 interposed (diastolic) ventilation every tenth compression (SCV/DV; n = 3 cats/technique). Fourteen of the 18 cats were resuscitated. Central aortic and venous pressures were determined concurrently with lead II electrocardiography. Arterial blood samples were collected during the base-line period (after pressure fluctuations had stabilized, with the cats spontaneously breathing room air), 2.5 minutes after the onset of arrest (defined as the cessation of aortic pressure fluctuations), and after 10 minutes of CPR. Arterial blood gas values during the base-line period or during the period of arrest were not significantly different between group-1 and group-2 cats. After CPR, arterial pH and bicarbonate values were not significantly different between groups or between technique categories. The PaCO2 values were significantly lower in cats resuscitated by SCV or by SCV/DV than in cats resuscitated by AHA (P less than 0.05). The PaO2 values were significantly (P less than 0.001) higher in group-2 cats than in group-1 cats and were significantly (P less than 0.001) different between each technique category, with cats resuscitated by AHA having the lowest PaO2 and cats resuscitated by SCV/DV having the highest PaO2. Body position, CPR technique, sex, weight, or arterial blood gas values after CPR were not predictors of successful resuscitation.     

Lymphangiosarcomas in cats: a retrospective study of 12 cases

Clinical, macroscopic, and histologic features of 12 lymphangiosarcomas in cats are described. Nine tumors were located in the subcutaneous tissue at the caudoventral abdominal wall (eight cats) or in the neck (one cat). The remaining three cats had lymphangiosarcomas around the cranial mesenteric artery (two cats) or precardial in the mediastinum (one cat). Macroscopically, the tumors were noncircumscribed, white, edematous, and intermixed with fat tissue. Histologic features varied from cleft-forming and cavernous growth to papilliform and solid patterns. Follow-up data were available for seven cats with subcutaneous lymphangiosarcomas. All these cats died or were euthanatized within 6 months after surgery because of poor wound healing, local recurrence, or distant metastases. The cats with abdominal or thoracic masses were either euthanatized at surgery or within 6 months after the first surgery because of recurrent chylothorax, chyloperitoneum, or distant metastases.     

Tick parasitism and antibodies to Borrelia burgdorferi in cats

Ticks were removed from naturally infested cats, and serum samples from these cats were tested for antibodies to Borrelia burgdorferi. Twenty-two of 93 cats (23.7%) had one or more motile stages of Ixodes dammini attached. Of 2 larvae and 20 nymphs removed from cats, 1 larva and 2 nymphs were infected with B burgdorferi. Spirochetes were not found in tissues of 13 female and 4 male ticks. Ten of 71 serum samples analyzed by indirect fluorescent antibody staining or ELISA contained antibodies to this spirochete. Maximal antibody titers were 1:256 and 1:2,560, respectively. At titers greater than or equal to 1:160 in ELISA, seropositivity ranged from 8.8% (n = 34 sera tested from 34 cats) in May through July to 33.3% (n = 12 cats tested) during February through April. In clinical studies of 30 cats, there were nearly equal percentages of seropositive cats with limb or joint disorders not accompanied by fever, anorexia, or fatigue (5 of 21 cats) and cats with these signs of illness but lacking lameness (2 of 9 cats.)     

Echocardiography, electrocardiography, and radiography of cats with dilatation cardiomyopathy, hypertrophic cardiomyopathy, and hyperthyroidism

The echocardiographic, ECG, and radiographic findings of sequentially examined cats with dilatation cardiomyopathy (DCM, n = 7), hypertrophic cardiomyopathy (HCM, n = 8), and hyperthyroidism (HT, n = 20) were compared with those of healthy control cats (n = 11). Cats with DCM were easily differentiated from healthy cats by echocardiography and from cats with HCM and HT by a dilated left ventricle at end-diastole with a mean +/- SD of 2.20 +/- 0.36 cm, reduced fractional shortening (2.9% +/- 3.7%), reduced aortic amplitude (0.07 +/- 0.05 cm), reduced left ventricular wall amplitude (0.09 +/- 0.09 cm), and increased E-point septal separation (0.83 +/- 0.29 cm). The cats with HCM were most consistently recognized echocardiographically by increased left ventricular wall thickness at end-diastole (0.75 +/- 0.12 cm). Some cats with HT had abnormal echocardiograms with left ventricular wall hypertrophy. These cats could usually be differentiated from the cats with HCM because of normal or increased ventricular wall amplitude, aortic amplitude, or percentage of thickening of the left ventricular wall and interventricular septum. Left atrial enlargement (left atrial diameter greater than 1.57 cm or left atrium/aorta greater than 1.75) was commonly detected by the echocardiogram in cats with DCM, HCM, or HT. The echocardiogram was helpful in differentiating the type of cardiomyopathy (DCM, HCM, or HT) when plain thoracic radiographs indicated that cardiomegaly existed. The ECG may have indicated incorrectly that there was left ventricular enlargement in some cats with HT, and it did not indicate consistently that left ventricular enlargement existed when present in cats with DCM or HCM. The ECG was a poor indicator of left atrial enlargement in all cats.     

Acute renal failure caused by lily ingestion in six cats

Acute renal failure was diagnosed in 6 cats that had ingested Easter lily or tiger lily plants. All 6 were treated medically; 2 underwent hemodialysis. Three cats survived the acute episode, and although they had chronic renal failure, they survived for more than 1.5 years. Two cats died despite aggressive medical management, including hemodialysis. One cat was euthanatized shortly after the diagnosis was made. Three of the cats were oliguric or anuric at the time of initial examination, and all 3 died. None of the 3 cats that survived had oliguria or anuria. Various members of the lily family (Liliaceae) can cause nephrotoxicosis in cats, but the toxic principle is not known. Although the prognosis for full recovery of cats with lily toxicosis is poor, long-term survival is possible with supportive care. The prognosis appears to be better for cats with nonoliguric renal failure.