Long-term remission and survival in dogs with high-grade, B cell lymphoma treated with chemotherapy with or without sequential low-dose rate half-body irradiation.

BACKGROUND: Standard of care for dogs with high-grade lymphoma, multiagent chemotherapy, achieves good initial responses but long-term remissions are infrequent; previous studies using half-body irradiation suggest improved long-term outcomes. HYPOTHESIS: The addition of low-dose rate half-body irradiation would improve outcomes in dogs with B-cell lymphoma. ANIMALS: Client-owned dogs with stage III or higher, substage a, B-cell lymphoma that achieved complete remission after 4 doses of multiagent chemotherapy. METHODS: A case-controlled design comparing 2-year remission and survival rates between dogs treated with CHOP-based chemotherapy and those treated with chemotherapy and sequential low-dose rate half-body irradiation. RESULTS: Thirty-eight dogs were enrolled with 18 included in final analysis, 9 prospectively-enrolled dogs and 9 case-matched historical controls. The irradiation cohort's 2-year disease-free rate was 56% whereas median duration exceeded the 730-day study period compared with 0% and 261 days in the chemotherapy only group. Remission duration significantly differed between cohorts (P < .01), hazard ratio 0.218 (95% CI: 0.06-0.77). The irradiation cohort's 2-year survival rate was 78% with median overall survival duration exceeding the 730 day study period compared with 11% and 286 days in the chemotherapy only group. Overall survival time significantly differed between cohorts (P < .02), hazard ratio 0.173 (95% CI: 0.03-0.839). CONCLUSIONS AND CLINICAL IMPORTANCE: The improved long-term outcome achieved by dogs administered sequential low-dose rate half-body irradiation in this study is similar to previous observational studies. Where long-term remission is sought in dogs with B-cell lymphoma low-dose rate half-body irradiation could be considered in addition to standard chemotherapy.

A retrospective multi-center study of treatment, outcome, and prognostic factors in 34 dogs with disseminated aspergillosis in Australia.

BACKGROUND: Disseminated aspergillosis (DA) in dogs has a guarded prognosis and there is a lack of a gold standard treatment protocol. OBJECTIVE: To retrospectively assess survival times and factors influencing survival times. ANIMALS: Dogs diagnosed with DA from January 2007 to June 2017. METHODS: Disseminated aspergillosis case data were retrieved from 13 Australian veterinary referral centers, with a diagnosis confirmed with culture or PCR. Factors influencing survival time after diagnosis were quantified using a Cox proportional hazards regression model. RESULTS: Thirty-four dogs met the study inclusion criteria. Twenty-two dogs were treated with antifungal treatment and 12 dogs received no antifungal treatment. Accounting for censoring of dogs that were either still alive on the date of data collection or were loss to follow-up, dogs treated with itraconazole alone (n = 8) had a median survival time (MST) of 63 (95% CI: 20-272) days compared to 830 (95% CI: 267-1259) days for the n = 14 dogs that received multimodal antifungal therapy ( χ 2 test statistic 8.6; df = 1; P < .01). The daily hazard of death (DHOD) for dogs with abnormally high serum creatinine concentration at the time of diagnosis was 7.4 (95% CI: 1.9-29) times that of dogs with serum creatinine within the reference interval. CONCLUSION AND CLINICAL IMPORTANCE: Serum creatinine concentration at the time of diagnosis is a useful prognostic indicator for survival after a diagnosis of DA. The MST for dogs treated with multimodal antifungal therapy is longer than itraconazole alone and warrant further investigation (P < .01).

Tracheal pseudomembrane secondary to aspiration pneumonia in a 6-year-old Ragdoll.

CASE SUMMARY: A 6-year-old female spayed Ragdoll presented with a 4-day history of acute onset non-productive retching, coughing and anorexia. A complete blood count, serum biochemistry, thoracic radiography and abdominal ultrasound were performed. Initially, aspiration pneumonia was suspected owing to an alveolar lung pattern in the right cranial ventral lung lobes seen on radiographs. The cat did not improve with empirical antibiotic therapy. Bronchoscopy and bronchoalveolar lavage were performed. An intraluminal tracheal mass was identified and removed via endoscopic guidance and gentle traction. Histopathology results were consistent with a fibrinous tracheal pseudomembrane. The cat was concurrently diagnosed with Pseudomonas aeruginosa pneumonia, which was confirmed on bronchoalveolar lavage. Pseudomonas aeruginosa was also cultured within the pseudomembrane. The cat was received antimicrobial therapy for his Pseudomonas pneumonia. In humans, fibrinous tracheal pseudomembranes occur uncommonly as a complication following endotracheal intubation and rarely due to infectious organisms. As there was no prior history of endotracheal intubation, the development of fibrinous tracheal pseudomembrane in this cat was suspected to be secondary to Pseudonomas aeruginosa aspiration pneumonia. RELEVANCE AND NOVEL INFORMATION: The present case report is the first to describe a tracheal pseudomembrane in a cat. Bronchoscopy-guided gentle traction and subsequent removal of the tracheal pseudomembrane resulted in a complete resolution of the clinical signs.

Safety and Tolerability of Hyperbaric Oxygen Therapy in Cats and Dogs.

This prospective clinical trial was designed to evaluate the safety of hyperbaric oxygen therapy (HBOT) in a population of cats and dogs with a variety of naturally occurring diseases. Seventy-eight dogs and twelve cats with various naturally occurring disease conditions, who had the potential to benefit from HBOT, were enrolled in the study. These patients were treated with HBOT in a monoplace hyperbaric oxygen chamber at 2 air pressure absolute for a treatment length of either 45 min or 60 min. There were 230 hyperbaric oxygen treatments performed during the study period. No major adverse effects were observed. There were 76 minor adverse effects recorded, which were not considered to be of clinical significance. Hyperbaric oxygen therapy was well tolerated and there were no major adverse effects recorded during treatment.

Successful treatment of Providencia rettgeri cholecystitis and neutrophilic cholangitis in a cat.

CASE SUMMARY: A 15-year-old male neutered domestic shorthair cat was presented with a recent history of seizures, diarrhoea, lethargy, fever and jaundice. Marked elevation of liver enzyme activity was present and ultrasound examination was suggestive of cholecystitis and hepatitis. Neutrophilic cholangitis was confirmed on histopathology of liver biopsies. Bile culture identified a monomicrobial infection with Providencia rettgeri, which was resistant to multiple antimicrobial agents. The cat was treated with oral pradofloxacin for 4 weeks and remained well 4 months later. RELEVANCE AND NOVEL INFORMATION: Providencia species are rarely reported in the veterinary literature and are an uncommon cause of disease in humans. The significance of this species in humans relates to the high prevalence of antimicrobial resistance. This is the first report of P rettgeri causing clinical illness in a cat and highlights the importance of bile cultures in hepatic disease.

Incidence of sterile hemorrhagic cystitis in dogs receiving cyclophosphamide orally for three days without concurrent furosemide as part of a chemotherapeutic treatment for lymphoma: 57 cases (2007-2012).

OBJECTIVE: To evaluate the incidence of sterile hemorrhagic cystitis (SHC) and other adverse effects in dogs following oral administration of the single-day, maximum-tolerated dose (MTD) of cyclophosphamide divided over 3 days as part of a multiagent chemotherapy protocol for treatment of lymphoma without concurrent administration of furosemide. DESIGN: Retrospective case series. ANIMALS: 57 dogs. PROCEDURES: Medical records were reviewed to identify dogs with lymphoma that underwent the described cyclophosphamide treatment. Information was obtained regarding signalment, lymphoma stage, concurrent diseases, cyclophosphamide doses administered, adverse effects (including SHC), remission rates, and outcomes. The incidence of SHC was compared with that of literature-derived historical control groups that received the MTD of cyclophosphamide as a single, 1-day dose with or without furosemide treatment. RESULTS: None of the 57 dogs developed SHC during the study period. Forty-seven of 57 (82%) dogs had complete remission of lymphoma. Other adverse effects were uncommon and self-limiting; no dogs had myelosuppression, and only 5 had mild gastrointestinal effects. Incidence of SHC was significantly lower than that reported for historical control dogs that received cyclophosphamide as a single dose without furosemide (24/219) and was not significantly different from that for historical control dogs that received cyclophosphamide as a single dose with furosemide (2/139). CONCLUSIONS AND CLINICAL RELEVANCE: No dogs in this study had SHC following oral administration of the single-day MTD of cyclophosphamide divided over a 3-day period without furosemide administration. Further research is needed to confirm whether this method of cyclophosphamide administration is equivalent or superior to the current single-dose administration method.

Pimobendan and its use in treating canine congestive heart failure.

Pimobendan, a calcium sensitizer and phosphodiesterase III inhibitor, has positive inotropic and vasodilatory properties. Its use in patients with naturally occurring congestive heart failure (CHF) has been studied in a number of blinded, randomized, multicenter clinical trials. It has been shown to improve quality of life, reduce heart insufficiency scores, and increase median survival times for patients with CHF due to dilated cardiomyopathy and myxomatous valvular disease. Although most studies have reported positive findings, some potential adverse effects have also been described. Studies are under way to further evaluate the effects of this novel positive inotrope and vasodilator in canine cardiac disease.

Multifocal Balamuthia mandrillaris infection in a dog in Australia.

A 6-year-old male golden retriever, with an 8-month history of seizures and a clinical diagnosis of lymphoma in the central nervous system, was (at the owner's request) euthanized after signs of respiratory distress and shock developed. Upon postmortem examination, the diagnoses of meningoencephalitis and pneumonia were made. A histological examination of selected tissues from both the lung and central nervous system revealed a severe, acute, multifocal, amoebic, embolic pneumonia and a severe, chronic, multifocal, nonsuppurative, amoebic meningoencephalitis. Indirect immunofluorescence analysis confirmed the presence of trophozoite and cyst stages of Balamuthia mandrillaris. This is the first report of B. mandrillaris (which is a free-living amoeba) causing fatal, multifocal granulomatous amoebiasis in a dog in Australia.