Evaluation of ifosfamide for treatment of various canine neoplasms

lfosfamide (3-[2-chloroethyl]-2[(2 chloroethyl)amino]tetrahydro-2H-1,3,2-oxazaphosphorine 2-oxide) is an alkylating agent with a broad spectrum of antitumor activity. The efficacy and toxicity of ifosfamide were evaluated in 72 dogs with spontaneously occurring tumors. Forty dogs (56%) had lymphoma, 31 (43%) had sarcomas, and 1 had a metastatic carcinoma. Five dogs received ifosfamide at dosages <350 mg/m2 IV. Neither toxicity nor response were observed, and the remaining dogs received ifosfamide at 350 mg/m2 (n = 18) and 375 mg/m2 body surface area IV (n = 49). Saline diuresis and the thiol compound mesna were used to prevent urothelial toxicity. Fifty-two dogs had measurable tumors and could be evaluated for response. Complete responses were seen in 1 dog with metastatic leiomyosarcoma of the urinary bladder and in 1 dog with metastatic cutaneous hemangiosarcoma. One dog with lymphoma had a partial response for 112 days. Six dogs with splenic hemangiosarcoma received ifosfamide postsplenectomy and their median survival time was 147 days. The acute dose limiting toxicity was neutropenia 7 days after administration of ifosfamide. The median and mean neutrophil counts 7 days after ifosfamide at 350 mg/m2 were 2,035 cells/microL and 4,773 cells/microL, respectively (n = 12). The median and mean neutrophil counts 7 days after ifosfamide at 375 mg/m2 were 2,500 cells/microL and 3,594 cells/microL, respectively (n = 37). No dog developed clinical or microscopic evidence of hemorrhagic cystitis. Ifosfamide appears safe to use in tumor-bearing dogs, and the evaluation of combination chemotherapy protocols that include ifosfamide should be considered.

Radiation therapy for long-term control of odontogenic tumours and epulis in three cats

Orthovoltage radiation was used to treat odontogenic tumours in three cats following incomplete surgical resection. Cats received a total radiation dose of 48-52 Gy over a period of 26-29 days. Acute toxicities were mild, consisting of hair loss within the radiation field in all cats, and mild mucositis in one cat. All cats had long-term (>35 months) control of their tumour, and two cats are still alive without recurrence of tumour 60 and 39 months, respectively, after completing treatment. Radiation therapy should be considered to be an adjuvant to incomplete surgery in cats with odontogenic neoplasms or epulides.

Lomustine (CCNU) for the treatment of resistant lymphoma in dogs

Forty-three dogs with lymphoma that had relapsed or had failed to achieve complete remission to previous chemotherapy were treated with lomustine (1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea [CCNU]) at a dosage of 90-100 mg/m2 body surface area p.o. every 3 weeks. Durable complete or partial responses occurred in 11 dogs for a median of 86 days. The acutely dose-limiting toxicosis was neutropenia 7 days after administration, resulting in a recommended dosage of 90 mg/m2. Cumulative thrombocytopenia occurred in dogs receiving continued CCNU treatment, and a dose interval of 3 weeks may be too short for continued administration of this drug. Toxicoses evident as fever or central nervous system signs or renal damage were uncommon or rare. CCNU is effective in the treatment of relapsed lymphoma.

Schizophrenia, psychotropic medication, and cataract

OBJECTIVE

To compare the distribution of cataract types between psychiatric patients diagnosed with schizophrenia and the general population not exposed to psychotropic medication, and to compare cataract prevalence between users and nonusers of various psychotropic medications in the general community.

DESIGN

Case-control.

PARTICIPANTS

A total of 151 (93%) eligible patients from a community mental health service and 3271 (83%) eligible residents from the Melbourne Visual Impairment Project (VIP) were examined.

MAIN OUTCOME MEASURES

All patients 40 years of age and older from a community mental health service and residents of nine randomly selected areas of Melbourne were eligible. Best-corrected distance visual acuity was determined using a 4-m logarithm of the minimum angle of resolution (LogMAR) chart. The presence of cataract was determined by photographs or slit-lamp examination using direct and indirect retroillumination. Anterior, cortical, nuclear, and posterior subcapsular cataracts were measured. Participants from the Melbourne VIP were classified as to whether they had taken benzodiazepams, phenothiazines, thioxanthenes, butyrophenols, tricyclic antidepressants, or monoamine oxidase inhibitors for at least 12 months during their lifetime.

RESULTS

The distribution of cataract type varied between persons with and without schizophrenia. Anterior subcapsular (ASC) cataract was significantly more prevalent (26%) in participants with schizophrenia from the community mental health service than Melbourne VIP participants (0.2%) not exposed to psychotropic medication (chi-square, 1 degree of freedom = 605.5, P = 0.001). This remained significant after controlling for age (odds ratios = 250, 95% confidence interval = 83.3, 1000). The distribution of the age-related cataract was similar across all groups of psychotropic medication users with the exception of the phenothiazine users. They had less of all types of the age-related cataracts, despite being slightly older than the control group (mean age, 60.0 vs. 58.4, t test = 0.85, P = 0.40). However, only cortical cataract in the phenothiazine group was statistically lower (chi-square, 1 degree of freedom = 3.96, P = 0.047).

CONCLUSION

This study has identified the need to investigate whether other newer agents, especially high-potency medications, cause ASC opacities if a certain threshold of exposure to psychotropic medications must be attained to develop cataract, or if schizophrenia itself is associated with cataract formation.

A combination chemotherapy protocol (VELCAP-L) for dogs with lymphoma

Ninety-eight dogs with lymphoma treated with a 5-drug combination chemotherapy regimen (vincristine, L-asparaginase, cyclophosphamide, doxorubicin, prednisone [VELCAP-L]) were evaluated for pretreatment characteristics predictive for response and remission duration. The complete remission rate was 69%, with a median remission duration of 55 weeks. Dogs with advanced stage of disease, constitutional signs, dogs that were older, and dogs that were dyspneic were less likely to achieve remission. Once in remission, small dogs and dogs without pretreatment thrombocytopenia were likely to have longer remission duration. Toxicoses were frequent, but rarely fatal, and no predictitive factors were found for a dog developing toxicoses. VELCAP-L is an effective treatment for dogs in stage I-III lymphoma, particularly in young, small animals.

Prognosis for dogs with stage I or II splenic hemangiosarcoma treated by splenectomy alone: 32 cases (1991-1993)

A retrospective analysis was performed on the case records of 32 dogs with Stage I or II splenic hemangiosarcoma that were treated by splenectomy alone and that survived the seven-day postoperative period. Median survival time for these 32 cases was 86 days (mean, 116 days; range, 14 to 470 days), and the one-year survival rate was estimated to be 6.25%. Survival was not influenced by signalment, presenting signs, stage of disease, or clinicopathological findings. The data provides a basis from which to evaluate adjuvant chemotherapy for splenic hemangiosarcoma that is confined to the spleen macroscopically.

Urinary tract infection in older adults

Urinary tract infection is common among older adults, although most individuals are asymptomatic. The prevalence of bacteriuria varies significantly with living situation and functional status. Asymptomatic bacteriuria is a benign condition and is not an independent risk factor for mortality in older adults. Treatment of asymptomatic bacteriuria generally is not indicated, but symptomatic urinary tract infection of the lower or upper tract dictates antibiotic therapy.

Use of focus groups to identify health promotion strategies for the early detection of diabetic retinopathy

BACKGROUND

People with diabetes do not regularly utilise eye services for the early prevention of vision loss due to diabetic eye disease. A community-based screening program has been initiated in Victoria to address this issue. To encourage people to take preventive eye health care measures, the most effective health promotion strategies were identified.

METHODS

Thirty-three health professionals were invited to attend focus groups. A sample of 35 people with diabetes was approached by their GPs or diabetes educators because of their motivation to participate in diabetes activities. Each group consisted of 10 members. Discussion points included the type of education messages available to people with diabetes; use of eye services among the participants with diabetes; and strategies required promoting the screening service.

RESULTS

Five focus groups were conducted. The discussions highlighted that a great deal could be achieved by using local community networks to promote the benefits of early detection of diabetic retinopathy and local screening program. The group members recommended that particular attention be directed to general practitioners and their distribution of materials to patients. Key issues for planning and implementing the program were highlighted. The groups urged development of strategies to encourage people with diabetes in rural Victoria to participate in a program for the early detection of diabetic retinopathy.

Mycobacterium fortuitum infection of the sternum. Review of the literature and case illustration

Sternal wound infection with atypical mycobacteria following open heart surgery is a rare occurrence. Previous reports have described infection by Mycobacterium fortuitum, an acid-fast bacillus and member of a larger family of rapidly growing mycobacteria. The source and mode of transmission have not been identified. Surgical debridement and the combination of aminoglycosides and quinolones have been shown to be effective methods of treatment. More recently, clarithromycin has been shown to be the drug of choice against rapidly growing mycobacteria. We describe a 49-year-old woman who underwent infundibular stenosis repair and in whom M fortuitum sternal osteomyelitis developed. Total sternectomy, muscle flap reconstruction, and antibiotic treatment successfully eradicated the infection.

Optimal treatment of urinary tract infections in elderly patients

Elderly patients are at high risk for urinary tract infection (UTI). Infections of the urinary tract may be classified as asymptomatic bacteriuria, uncomplicated cystitis, uncomplicated pyelonephritis or complicated UTI. The micro-organisms responsible for causing UTI are largely predictable and dictate therapy when indicated. UTIs may be diagnosed by both nonculture and culture techniques. Asymptomatic bacteriuria, though quite common in the elderly, should rarely be treated. Treatment of symptomatic uncomplicated and complicated UTIs is largely dictated by the known or expected pathogen(s) and classification of the infection. Additional features affecting the treatment of UTI in the elderly include allergies, adverse reactions to therapy, drug interactions and modification for renal insufficiency.

A comparison of doxorubicin and COP for maintenance of remission in cats with lymphoma

Thirty-eight cats with lymphoma were treated with vincristine, cyclophosphamide, and prednisone (COP). They were randomized at entry to receive maintenance chemotherapy consisting of either single-agent doxorubicin or continued COP therapy, starting on week 4 of treatment and continuing for 6 months or until relapse. Eighteen cats achieved complete clinical remission after COP induction chemotherapy. The median remission duration for 11 cats continuing to receive COP was 83 days, which was significantly shorter than for 7 cats that received doxorubicin (281 days). Thus, doxorubicin should be considered a well-tolerated and efficacious agent for the maintenance of remission in cats with lymphoma.

Discrimination of epidemic and sporadic isolates of Acinetobacter baumannii by repetitive element PCR-mediated DNA fingerprinting

In 1990, there was a significant increase in the number of lower respiratory tract infections and surgical wound infections in the adult intensive care units of our tertiary care teaching hospital caused by Acinetobacter baumannii compared with the number in 1989. During the 5-month period from April through August 1990, 84 isolates of A. baumannii were recovered from 50 hospitalized patients. Biotyping, comparison of antibiograms, plasmid analysis, and DNA polymorphisms of 20 isolates from 20 different patients, determined by the use of repetitive element PCR with primers aimed at repetitive extragenic palindromic sequences and enterobacterial repetitive intergenic consensus sequences, were used to investigate this apparent outbreak. Biotyping, antibiograms, plasmid analysis, and enterobacterial repetitive intergenic consensus PCR were not useful epidemiologically. Repetitive element PCR-mediated DNA fingerprinting using repetitive extragenic palindromic primers discriminated between epidemic and sporadic strains of A. baumannii and demonstrated four discrete clusters which were unique epidemiologically.

Beta-lactams versus glycopeptides in treatment of subcutaneous abscesses infected with Staphylococcus aureus

The antibacterial efficacies of the beta-lactam antibiotics nafcillin and cefazolin were compared with those of the glycopeptide antibiotics vancomycin and teicoplanin in rats with subcutaneous abscesses infected with methicillin-susceptible Staphylococcus aureus. Animals were treated with antibiotics or diluent for 3 or 7 days. Rats receiving any antibiotic treatment, with the exception of teicoplanin-treated animals at day 7, had lower bacterial counts in their abscesses than did controls at days 3 and 7. Rats in the nafcillin and cefazolin treatment groups had lower bacterial counts in their abscesses than did rats in the vancomycin and teicoplanin treatment groups at days 3 and 7. The beta-lactam antibiotics were more effective therapy than the glycopeptide antibiotics in rats with subcutaneous abscesses infected with methicillin-susceptible S. aureus. In vitro, animal, and clinical data comparing beta-lactam and glycopeptide treatment of S. aureus infections were reviewed along with the resulting treatment recommendations.