Feline phaeohyphomycosis: treatment with ketaconazole and 5-fluorocytosine

Two cats with phaeohyphomycosis, one infected with Phialophora verrucosa and the other with Exophiala jeanselmei, were treated with ketaconazole alone and in combination with 5-fluorocytosine after recurrence of the infections following surgical excision. The drugs were given orally at various doses and for various lengths of time, but were ineffective. Hepatocellular damage occurred in one cat.     

Feline Lymphoma (145 Cases): Proliferation Indices, Cluster of Differentiation 3 Immunoreactivity, and Their Association with Prognosis in 90 Cats

Paraffin-embedded, formalin-fixed tissue samples from 145 cats with lymphoma were analyzed for cluster of differentiation 3 (CD3, a surface antigen) immunoreactivity, argyrophilic nucleolar organizer region (AgNOR) frequency, and proliferating cell nuclear antigen labeling index (PCNA-LI). This information along with signalment, anatomic site, and feline leukemia virus (FeLV) antigen status was used to determine the potential of these indicators to predict response to therapy, remission, and survival times, and to characterize cats with lymphoma in the era of general availability of FeLV testing and vaccination. Alimentary lymphoma, primarily occurring in older, FeLV-negative cats, was the most common site of involvement. Although the majority of tumors from FeLV-positive cats were CD3-immunoreactive, only one half of CD3-immunoreactive tumors occurred in FeLV-positive cats. Median remission duration and survival times were 126 days and 143 days, respectively, for all cats. Measures of tumor cell proliferation (AgNOR frequency and PCNA-LI) and CD3-immunoreactivity were not predictive of outcome. When all prognostic factors were accounted for by multivariate analysis, response to therapy, FeLV status, and clinical substage were predictive of outcome. FeLV-negative cats that achieved a complete response following induction therapy were likely to have durable (ie, > 6-month) responses, particularly when doxorubicin was included in the chemotherapy protocol. However, FeLV-positive cats had significantly shorter remission and survival times with available chemotherapeutic protocols.     

Feline uveitis: diagnosis and treatment

Uveitis is the inflammation of any or all parts of the vascular tunic of the eye; the vascular tunic includes the iris, the ciliary body, and choroid. A good knowledge base, up-to-date reference materials, and good instruments will improve the diagnosis of uveitis. Feline uveitis can be caused by numerous infectious agents in addition to neoplasia and less likely trauma. The infectious causes most commonly associated with feline uveitis include feline leukemia virus, feline immunodeficiency virus, feline infectious peritonitis, systemic fungal infections, toxoplasmosis, and bartonellosis. Neoplastic causes of uveitis can be primary or secondary. Iris melanoma is the most common primary uveal neoplasia and trauma-associated sarcoma is the second most common primary uveal neoplasia. Treatment for the clinical signs of anterior uveitis include topical steroidal or non-steroidal anti-inflammatory agents, parasympatholytic agents for ciliary spasm, to keep the pupil dilated, and to prevent posterior synechia. Posterior uveitis should be treated with systemic medications that will address the underlying cause. Enucleation of blind, painful eyes not responsive to medications is a means to alleviate the animal's discomfort and to further diagnose the underlying cause.     

Feline cutaneous fibropapillomas: clinicopathologic findings and association with papillomavirus infection

Twenty-three feline cutaneous fibropapillomas with histologic features similar to equine sarcoids were diagnosed. They were characterized by dermal fibroblastic proliferation with overlying, often ulcerated hyperplastic epidermis. Electron microscopic findings supported the fibroblastic nature of the neoplastic cells. The 23 tumors came from 20 cats and were submitted from veterinary clinics in Wisconsin and Minnesota. These tumors occurred most commonly in young cats and were found primarily on the head, neck, and digits. Fifteen of the 17 cats for which breed was reported were domestic shorthair cats. In 11/20 cases, there was confirmed exposure to cattle. Local recurrence of the tumor following surgical excision was reported in 7 of the 18 cats for which follow-up information was available. Metastasis was not documented in any of the cases. Two of the 19 tumors tested by polymerase chain reaction (PCR) had no amplifiable DNA. The remaining 17 were positive for papillomavirus by PCR. No papillomavirus DNA was detected in three other feline skin tumors (cutaneous mast cell tumor, malignant lymphoma, and fibrosarcoma) that served as controls. This is the first report of detection of papillomavirus in feline tumors that have clinicopathologic features similar to equine sarcoids.     

Canine Thyroid Carcinomas: Clinical Occurrence, Staging by Means of Scintiscans, and Therapy of 15 Cases

Tumor characteristics and degree of metastatic disease are outlined for 15 cases of canine thyroid carcinoma based on physical, laboratory, and radiographic examinations. Results of thyroid scintiscans using sodium pertechnetate are discussed in relation to clinical staging. Surgical resection was the primary therapy. Adjuvant therapy included thyroid replacement therapy, and ¹³¹I and ⁶⁰Co radiotherapy.     

Feline systemic hypertension: Diagnosis and management

PRACTICAL RELEVANCE: the clinical importance of feline hypertension has been recognised for many years and most feline practitioners are quite familiar with this syndrome. Once systemic hypertension is identified, long-term management of the patient is needed to avoid catastrophic (eg, blindness due to retinal detachment) or subtle (eg, accelerated renal damage) target organ damage. PATIENT GROUP: feline systemic hypertension is most commonly a complication of renal disease and hyperthyroidism, both diseases of older feline patients. By 15 years of age, the probability of having at least one of these two diseases is high. As well cared for cats are living longer, optimal long-term management of feline hypertension in patients with concurrent diseases is an issue of clinical importance. CLINICAL CHALLENGES: obtaining accurate blood pressure measurements in patients that are anxious, fractious or just plain uncooperative remains a significant issue in feline medicine, as does confident analysis of results from these patients. DIAGNOSTICS: careful measurement of systolic blood pressure using Doppler or oscillometric techniques in conjunction with evaluation for evidence of hypertensive choroidopathy (funduscopic examination) and hypertensive cardiac changes (thoracic auscultation) are essential to the diagnosis of systemic hypertension in cats. Other diagnostic techniques, including evaluation of renal and thyroid function, are needed to detect the underlying disease condition. EVIDENCE BASE: numerous well-designed clinical studies have greatly advanced our understanding of the most appropriate methods of diagnosis and therapy of feline hypertension.     

Feline systemic hypertension: Classification and pathogenesis

PRACTICAL RELEVANCE: the increased availability of indirect blood pressure monitoring devices in clinical practice over the past decade has highlighted the significance of systemic hypertension in the feline population. Without routine monitoring and appropriate intervention, cats with undiagnosed systemic hypertension may first be presented with sudden-onset blindness as a consequence of either hyphaema or retinal detachment. CLINICAL CHALLENGES: the primary aim in the early diagnosis and treatment of systemic hypertension is prevention of hypertensive target organ damage (with respect to the eye, kidney, cardiovascular and central nervous systems, in particular). A prerequisite is a knowledge of the pathophysiological mechanisms and disease conditions that may contribute to the development of hypertension. This allows the clinician to determine those cases in which blood pressure assessment and longitudinal monitoring is essential and can assist in determining appropriate therapeutic strategies for control of blood pressure. Recent studies have also begun to explore the relationship that systemic hypertension may have with proteinuria and the progression of kidney disease. PATIENT GROUP: the geriatric cat appears most susceptible to the development of systemic hypertension, and monitoring of systolic blood pressure is often advocated as part of a routine health screen in cats over 9-12 years old. Consideration must also be given to cats suspected of having an underlying disease such as chronic kidney disease or hyperthyroidism, or which are receiving therapeutic agents, irrespective of their age. EVIDENCE BASE: much of our understanding of the pathogenesis of feline hypertension is extrapolated from studies performed in experimental animal models or in human patients, and interspecies differences are often poorly understood.     

Prevalence of Feline Chlamydia psittaci and Feline Herpesvirus 1 in Cats with Upper Respiratory Tract Disease

The epidemiology of feline chlamydiosis and feline herpesvirus 1 (FHV1) infection in cats was determined using a duplex polymerase chain reaction assay. In cats with upper respiratory tract disease (URTD), prevalences of 66 (14.3%) of 462 cats and 98 (21.2%) of 462 cats were found for Chlamydia psittaci and FHV1, respectively. In cats without URTD, prevalences were 1/87 (1.1%) for both pathogens. Younger cats, cats sampled in summer, and cats with conjunctivitis were more likely to be positive for C psittaci than were cats sampled in other seasons and cats without conjunctivitis. Cats with recent contact with cats outside the household, cats with acute disease, and sneezing cats were more likely to be positive for FHV1 than were cats that had not had recent contact with cats outside the household, cats with chronic disease, and cats that were not sneezing. Purebred cats were less likely to be positive for FHV1 than were mixed breed cats and prevalence varied with year of sampling. Coinfection with both pathogens was lower than would be expected from their respective prevalences. Vaccinated cats were equally likely to be positive for FHV1 as unvaccinated cats. In sneezing cats FHV1 was more likely to be detected than C psittaci, particularly in acute cases, and when sneezing was not accompanied by conjunctivitis. Cats with reproductive disease concurrent with URTD were more likely to be infected with FHV1 than with C psittaci. Thus, the factors that should be considered in clinical diagnoses of C psittaci infections are the presence of conjunctivitis, age, and season, whereas contact with other cats, acute disease, and sneezing should be considered in diagnoses of FHV1 infection.     

Feline hyperthyroidism: A descriptive and case-control study

The frequency of diagnosis of feline hyperthyroidism has increased dramatically since the late 1970s. Whether this increase reflects enhanced diagnostic acumen or an actual increase in the incidence of this disease, or both, is unknown. It seems likely, in view of the distinctive nature of the signs and the lack of evidence of thyroid enlargement and clinical signs in previous feline necropsy series, that feline hyperthyroidism is truly occurring with increased frequency today.

A case-control study was undertaken to identify possible risk factors for this disease. Owners of 56 cats with feline hyperthyroidism and 117 controls were questioned about their cats' exposure to various potential risk factors (e.g., diet, medications) and these exposures were compared. Elevated odds ratios were associated with regular treatment with flea sprays or powders, living strictly indoors and having reported exposure to lawn herbicides, fertilizers or pesticides. Cases were also more likely to receive canned food and were less likely to be Siamese than controls. The relevance of these factors to the etiology of feline hyperthyroidism is discussed.     

Feline genetics: clinical applications and genetic testing

DNA testing for domestic cat diseases and appearance traits is a rapidly growing asset for veterinary medicine. Approximately 33 genes contain 50 mutations that cause feline health problems or alterations in the cat's appearance. A variety of commercial laboratories can now perform cat genetic diagnostics, allowing both the veterinary clinician and the private owner to obtain DNA test results. DNA is easily obtained from a cat via a buccal swab with a standard cotton bud or cytological brush, allowing DNA samples to be easily sent to any laboratory in the world. The DNA test results identify carriers of the traits, predict the incidence of traits from breeding programs, and influence medical prognoses and treatments. An overall goal of identifying these genetic mutations is the correction of the defect via gene therapies and designer drug therapies. Thus, genetic testing is an effective preventative medicine and a potential ultimate cure. However, genetic diagnostic tests may still be novel for many veterinary practitioners and their application in the clinical setting needs to have the same scrutiny as any other diagnostic procedure. This article will review the genetic tests for the domestic cat, potential sources of error for genetic testing, and the pros and cons of DNA results in veterinary medicine. Highlighted are genetic tests specific to the individual cat, which are a part of the cat's internal genome.