Cyclosporine and ketoconazole for the treatment of perianal fistulas in dogs

OBJECTIVE: To evaluate efficacy and cost of using cyclosporine and ketoconazole for the treatment of perianal fistulas in dogs. DESIGN: Clinical trial. ANIMALS: 12 dogs with perianal fistulas. PROCEDURE: Dogs received cyclosporine and ketoconazole orally (target whole blood trough cyclosporine concentrations of 400 to 600 ng/ml). Study endpoints were resolution of clinical signs, remission, and recurrence of disease. Adverse effects and cost of medications were reported. Results were compared with those from previous studies in humans and in dogs in which single agent cyclosporine treatment for perianal fistulas was used. RESULTS: All dogs had resolution of clinical signs. Eight dogs went into remission; however, 5 of those 8 had recurrence of fistulas. Adverse effects of treatment were minimal and well tolerated. Cost of treatment was comparable to traditional surgical options and less than single agent cyclosporine treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of cyclosporine with ketoconazole is an effective and cost-comparable treatment for perianal fistulas in dogs.     

Cyclosporin treatment of perianal fistulas in dogs.

The purpose of this pilot study was to investigate the efficacy of cyclosporin in treating perianal fistulas (PAF) in dogs. Based on resolution of all fistulas in all dogs with remission times up to > 18 months, we conclude that cyclosporin therapy is the treatment of choice for PAF in dogs.     

Castration for treatment of perianal gland neoplasms in the dog

Neoplasms of the perianal gland are common in the dog, particularly the male. Adenomas of the gland develop about 4.5 times more often than do carcinomas of the gland. The adenoma is hormone dependent; thus, castration without excision of the tumor has been successful in promoting regression without recurrence. Microscopic examination of the testes from dogs with perianal gland neoplasms has revealed 1 in 10 with tubular atrophy and 1 in 3 with testicular neoplasia. Interstitial cell tumors have been seen more often than other cell types of testis tumors.     

Use of ketoconazole in treatment of dermatophytosis in a dog

Ketoconazole, an antifungal imidazole derivative, was used successfully to treat Tricophyton mentagrophytes infection in a dog. The drug was administered orally (11 mg/kg of body weight, q 24 h) and continued for 90 days. Though ketoconazole is not licensed currently for veterinary purposes, it has been used successfully to treat dermatophyte infections as well as intermediate and deep fungal diseases in both dogs and cats. In this case, ketoconazole was found to be nontoxic and less expensive than griseofulvin in the treatment of dermatophytosis.     

Clinical observations of the treatment of canine perianal fistulas with topical tacrolimus in 10 dogs

Tacrolimus ointment, a potent immunosuppressive medication, was evaluated for efficacy in the treatment of perianal fistulas in dogs. Ten dogs with perianal fistulas were treated with topical tacrolimus ointment once to twice daily for 16 weeks. Full healing of the fistulas occurred in 50% and was noticeably improved in 90% of dogs.     

Results of surgical excision of perianal fistulas in dogs

Eighty-seven dogs that had perianal fistulas diagnosed at the Veterinary Medical Teaching Hospital, University of California, Davis, were treated by excision of the diseased tissues and bilateral anal sacculectomy. Males were affected more often than females (66 to 21), and the German Shepherd Dog was the predominant breed (59 of 87). Information from owners regarding long-term postoperative progress was available for 41 dogs. Twenty-two of the 41 dogs had been euthanatized, 15 (36.6%) because of complications related to perianal fistulas and 7 because of unrelated causes. The mean postoperative period, ie, from the time of surgery to the time of euthanasia, was 34.7 months (range, 1 to 82 months). The remaining 19 dogs were examined after a mean postoperative period of 42.3 months (range, 13 to 100 months). Postoperative complications included development of clinically evident fistulas in 23 of the 41 dogs (56.1%), lack of normal continence (26.8%), tenesmus (19.5%), flatulence (17.1%), and anal stricture (14.6%). Twenty-one of the 41 dogs (51.2%) were judged by their owners to be satisfactory pets or to have been satisfactory pets before euthanasia for unrelated reasons     

Cyclosporine treatment of perianal gland adenoma concurrent with benign prostatic hyperplasia in a dog

A 13-year-old, intact male, mixed-breed dog was evaluated for multiple intradermal nodules around the anus. The nodules were diagnosed as perianal gland adenoma based on histopathologic examination. After therapy with cyclosporin A for 5 wk, the perianal masses were moderately shrunken. The dog's condition has remained stable over 6 mo.     

Multiple perianal infundibular follicular cysts in a dog

This case report describes a 7‐year‐old male cocker spaniel dog with multiple perianal infundibular follicular cysts. Clinically the dog had moderate anal sacculitis, peri‐anal pruritus causing it to ‘scoot’ and lick the area. On examination of the perianal area, there were over 100 firm, well circumscribed papules, ranged from 0.2 to 0.5 cm in diameter with a central pore, and were found in the perianal region. Alopecia was present in the perianal region. The skin tissue in the perianal region resected surgically was submitted for histological examination. Microscopically, the tissue revealed multiple dilated cysts filled with keratins and the papules corresponded to infundibular follicular cysts. The affected dog showed moderate anal sacculitis. Anal sacculitis commonly causes repeated scooting or licking the area around the anus. Therefore, the multiple follicular cysts in the present case appear to be primarily a sequela to chronic external trauma to the perianal area, probably in response to anal sacculitis. To the best of the authors’ knowledge, the present report is the first documented case of multiple perianal infundibular follicular cysts in a dog.     

Anatomic predisposition to perianal fistulae formation in the German shepherd dog

Gross and microanatomic features which may predispose the German Shepherd Dog to perianal fistulae formation were studied in 2 groups of clinically healthy dogs: a predisposed group (German Shepherd Dogs) and a control group comprising breeds not ordinarily affected by perianal fistulae. The dimensions of the anal crypts (depth, base width, and length), measured and compared statistically between samples, identified no significant variation between groups (P greater than 0.05). Major tissue components of the anal canal were measured microscopically and were similarly evaluated: epithelial height in each zone, thickness of the lamina propria in each zone, thickness of the internal and external anal sphincter muscles, and density of the circumanal, sebaceous, and apocrine sweat glands. The only significant finding was an increase in density of apocrine sweat glands in the zona cutanea in the pre-disposed dog group. In a semiquantitative analysis of the inflammatory responses frequently seen in the anal glands, more mature fibroplasia was seen in the German Shepherd Dogs, indicating that inflammation was more longstanding in this group.     

Digoxin-quinidine interaction in the dog

In seven healthy dogs, digoxin was given as an oral loading dose (0.05 mg/kg/day) on the first day, followed by an oral maintenance dose (0.02 mg/kg/day) during the next 14 days. On the sixth day of digoxin treatment, oral quinidine (200 mg b.i.d.) was added until the tenth day. Plasma concentrations of digoxin and quinidine were measured; in three of the seven dogs ECG and physical signs of digitalis toxicity were evaluated. The average steady state plasma concentration of digoxin increased significantly ( P <0.01) during quinidine administration (from 1.4 to 2.3 ng/ml). On the days that digoxin was administered without quinidine, none of the dogs vomited nor was anorectic; the PQ-interval increased significantly ( P <0.01) between 0.01 and 0.03 s. When quinidine was added, vomiting and anorexia occurred but no further increases in die PQ-interval were seen.     

Evaluation of azathioprine on lesion severity and lymphocyte blastogenesis in dogs with perianal fistulas

Fourteen dogs with perianal fistulas were entered into a prospective clinical study to investigate the effects of long-term azathioprine on clinical outcome and to determine if the clinical results correlated with lymphocyte blastogenesis tests. Complete remission of perianal fistulas was seen in eight (57%) of 14 dogs; partial remission occurred in one (7%) dog; and no response was detected in five (36%) dogs. The results of lymphocyte blastogenesis assays did not correlate with therapeutic response.     

Evaluation of ketoconazole and itraconazole for treatment of disseminated cryptococcosis in cats

During the first part of a study, cats were inoculated with Cryptococcus neoformans via the following routes: intradermal, intranasal, IV, and intracisternal. Only use of the IV route of inoculation consistently induced disseminated cryptococcosis. In the second part of the study, disseminated cryptococcosis was experimentally induced in cats via IV inoculation of C neoformans. One month after inoculation, 3 cats were treated with ketoconazole (10 mg/kg of body weight/d) and 3 cats were treated with itraconazole (10 mg/kg/d) for 3 months. One of the ketoconazole-treated and 2 of the itraconazole-treated cats also had cryptococcosis of the CNS when treatment was begun. During treatment, serum cryptococcal antigen titer progressively decreased in all cats. Abnormalities in CBC values or the serum biochemical profile were not found in any cat during treatment. However, all ketoconazole-treated cats became anorectic and lost weight. Side effects were not seen in itraconazole-treated cats. During the 3-month posttreatment observation period, all cats remained healthy. At necropsy, histologic evidence of cryptococcosis was not found in the 3 ketoconazole-treated cats or in 2 of the itraconazole-treated cats. In the third itraconazole-treated cat, cryptococcal organisms were found in the kidneys.     

Metastases of perianal gland carcinoma in a dog: palliative tumor therapy

Palliative radiation therapy may provide significant relief in symptoms in pets with incurable cancer. Therapy is applied over a short period of time, using larger than normal fractional doses. Palliative radiation leads to minimal or no side effects. This case report describes the situation of a miniature poodle that was presented with severe dyschezia as well as fresh blood in the feces. The dog had a large abdominal mass which was diagnosed as lymph-node metastasis of a perianal gland carcinoma. Therapy included palliative radiation as well as chemotherapy. Six months after initial presentation the dog is free of clinical symptoms.     

Presumptive Nocardia spp. infection in a dog treated with cyclosporin and ketoconazole

Abstract

CASE HISTORY: A dog that had received 8 months of cyclosporin and ketoconazole therapy for treatment of atopic dermatitis subsequently developed severe neurological disease, that failed to respond to treatment with trimethoprim-sulphadiazine and clindamycin.

HISTOPATHOLOGICAL FINDINGS: Histopathological examination of the pulmonary parenchyma and spinal cord revealed loose aggregates of Gram-positive, partially acid-fast, fine, beaded, filamentous bacteria, most consistent with Nocardia spp.

DIAGNOSIS: A presumptive diagnosis was made of disseminated nocardiosis of the spinal cord and lungs.

CLINICAL RELEVANCE: Nocardia spp. is an opportunistic actinomycete that may cause disseminated disease, particularly in immunocompromised animals. Cyclosporin is used in veterinary medicine to control immune-mediated and allergic disorders, with few reported adverse side effects. This case gives further evidence that involvement of the spinal cord in nocardiosis of the central nervous system (CNS) carries a poor prognosis, and opportunistic infection by Nocardia spp. may be a potential complication of immunosuppressive cyclosporin therapy in the dog.     

Use of ketoconazole in the treatment of canine nasal aspergillosis

Fifteen dogs with nasal aspergillosis were treated with ketoconazole (5 mg/kg of body weight, q 12 h, PO) for 2 to 18 weeks. Four dogs whose conditions deteriorated during treatment received ketoconazole for less than the prescribed 6 weeks. Six months or more later, only 47% of the dogs were determined to be disease-free, on the basis of no fungal growth on culture. It was concluded that ketoconazole at this dosage is a useful treatment for canine nasal aspergillosis, but is no more effective than thiabendazole.