Survival and prognostic indicators for cycad intoxication in dogs

Emerging Plant Intoxications in Domestic Animals: A European Perspective

Exposure to phytotoxins that are present in imported ornamental or native plants is an important cause of animal disease. Factors such as animal behaviors (especially indoor pets), climate change, and an increase in the global market for household and ornamental plants led to the appearance of new, previously unreported plant poisonings in Europe. This has resulted in an increase in the incidence of rarely reported intoxications. This review presents some of the emerging and well-established plant species that are responsible for poisoning episodes in companion animals and livestock in Europe. The main plant species are described, and the mechanism of action of the primary active agents and their clinical effects are presented. Data reflecting the real incidence of emerging poisoning cases from plant toxins are scarce to nonexistent in most European countries due to a lack of a centralized reporting/poison control system. The diversity of plant species and phytotoxins, as well as the emerging nature of certain plant poisonings, warrant a continuous update of knowledge by veterinarians and animal owners. The taxonomy and active agents present in these plants should be communicated to ensure awareness of the risks these toxins pose for domestic animals.

Plants and mushrooms associated with animal poisoning incidents in South Africa

Background

There is extensive literature on animal poisoning from plants and mushrooms worldwide; however, there is limited account of poisoning from South Africa.

Methods

This study sought to describe and provide an overview of animal poison exposures in South Africa. Poisoning episodes reported to the Poisons Information Helpline of the Western Cape, jointly run by the Poisons Information Centres at the Red Cross War Memorial Children’s Hospital and Tygerberg Hospital over a period of approximately 2.5 years, from June 2015 to November 2017, were analysed to identify exposure patterns, severity and clinical outcomes.

Results

Alien plant species accounted for most cases (n=10) of reported poison exposures. Among the 26 recorded animal poisoning episodes, the dog was the most commonly implicated species (n=24), whereas just two enquiries were related to other animals (one rabbit and one cow). There were 20 plant cases and 6 mushroom cases (all dogs). There was only one fatal case involving cycad in a dog.

Conclusion

Features of animal poisoning in South Africa were similar to those in other countries. The reported cases of animals exposed to poisonous plants and mushrooms could represent only a fraction of the actual exposures. Since most reported cases involved taxa that could not be identified to species level, more attention should be paid in case reporting and in animal poisoning prevention, engaging the public to enable people to recognise potentially hazardous plants and reduce the risk of poisoning in animals.

Plant and Fungal Hepatotoxicities of Cattle in Australia, with a Focus on Minimally Understood Toxins

Plant- and fungus-derived hepatotoxins are a major cause of disease and production losses in ruminants in Australia and around the world. Many are well studied and described in the literature; however, this is not the case for a number of hepatotoxicities with economic and animal welfare impacts, such as acute bovine liver disease (ABLD), brassica-associated liver disease (BALD) and Trema tomentosa, Argentipallium blandowskianum and Lythrum hyssopifolia toxicity. Additionally, significant overlap in the clinical presentation and pathology of these conditions can present a diagnostic challenge for veterinarians. This review summarizes the current and most recently published knowledge of common plant- and fungus-associated hepatotoxins affecting cattle in Australia, with a focus on the mechanisms of toxicity and distinguishing diagnostic features. Consolidation of the current understanding of hepatotoxic mechanisms in cattle provides insight into the potential mechanisms of lesser-known toxins, including cellular and subcellular targets and potential metabolic pathways. In the absence of specific etiological investigations, the study of epidemiological, clinical and pathological features of hepatotoxicity provides valuable insights into potential toxic mechanisms and is integral for the successful diagnosis and management of these conditions.

The characterization of cycad palm toxicosis and treatment effects in 130 dogs

The purpose of this retrospective study is to characterize the clinical signs, laboratory values, treatment modalities and mortality outcomes related to cycad palm toxicosis in dogs and to identify medical interventions that potentially correlate with mortality. Dogs with confirmed cycad palm ingestion were identified by reviewing medical records from two private veterinary referral centres for key terms and phrases indicative of cycad palm toxicosis. Of 130 dogs included, 107 (82.3%) presented with clinical signs. A total of 2 (1.5%) died and 14 (10.8%) were euthanized. Diarrhea, lethargy and mortality were all associated with an elevated initial alanine transaminase (ALT) concentration. Overall mortality was 12.3%, with a significantly higher proportion of dogs with an ALT concentration <125 U/L surviving compared to dogs with an elevated ALT concentration. Treatment with activated charcoal reduced the odds of death among all dogs by 82% and was even more protective among dogs with an elevated initial ALT concentration. Among dogs that had an initial platelet count performed, the presence of thrombocytopenia (<200,000/μL) was a negative prognostic indicator and was associated with a significant increase in mortality. Given the high mortality rates reported for cycad palm toxicosis, it is imperative to identify early clinical indicators of mortality as well as treatments that reduce mortality.

Presumptive Cycad Toxicosis in a Dog. Clinical and Magnetic Resonance Imaging Findings: A Case Report

Cases of cycad toxicosis have been described in dogs that have presented with gastrointestinal, hematologic, hepatic, neurological, and carcinogenic signs. This case report describes brain magnetic resonance imaging (MRI) lesions in a dog with gastrointestinal and neurological signs secondary to cycad toxicosis. A 5-year-old neutered female Jack Russell terrier presented with a 2-days history of gastroenteric signs, progressive generalized tremors, and altered mentation after possible ingestion of Cycad revoluta. Neurologic examinations revealed disorientation, a wide-based stance, severe spasticity of the four limbs, intention tremors, severe cerebellar ataxia, decreased postural reactions in all four limbs, and intermittent decreased menace response in both eyes—all of which are consistent with a multifocal intracranial disorder involving the forebrain and cerebellum. A brain MRI showed diffuse/ill-defined, intra-axial bilateral and symmetrical changes, predominantly affecting the white matter of the cerebral hemispheres, thalamus, hippocampus, and cerebellum. A presumptive diagnosis of toxic-metabolic encephalopathy was made. Medical management of the clinical signs was performed, and the dog was discharged 7 days after presentation with no neurological abnormalities. Two and 8 weeks later, complete blood count (CBC), chemistry, electrolytes, and 8 weeks later brain MRI were performed, revealing no abnormalities. To the best of the authors' knowledge, this is the first case report describing lesions detected by brain MRI secondary to cycad toxicosis as well as a complete resolution of brain lesions on a follow-up MRI 8 weeks later.

Indoor Companion Animal Poisoning by Plants in Europe

Indoor plant poisoning poses serious threats to companion animals. One of the major reasons of this kind of hazard can be identified in the increased amount of time that the pets spend indoor, sharing the domestic environment with their owners. In this review, the toxic houseplants most commonly associated with companion animal poisoning in Europe and well-documented in the literature are emphasized. An analysis of the major and emerging plant species accountable for companion animal poisoning is proposed, in order to provide a framework of the factors influencing these incidents. Indeed, knowing the way substances may induce toxic effects in companion animals can be useful in allowing easier diagnosis and treatment processes. In conclusion, the Authors argue that a better characterization of the phenomenon, as well as of its extent, would be allowed by the availability of a centralized system for the data collection. Furthermore, better information and awareness on the issue may help developing a focused corrective approach to prevent indoor pet poisoning in Europe.

Effect of clinical signs, endocrinopathies, timing of surgery, hyperlipidemia, and hyperbilirubinemia on outcome in dogs with gallbladder mucocele

Gallbladder mucocele (GBM) is a common extra-hepatic biliary syndrome in dogs with death rates ranging from 7 to 45%. Therefore, the aim of this study was to identify the association of survival with variables that could be utilized to improve clinical decisions. A total of 1194 dogs with a gross and histopathological diagnosis of GBM were included from 41 veterinary referral hospitals in this retrospective study. Dogs with GBM that demonstrated abnormal clinical signs had significantly greater odds of death than subclinical dogs in a univariable analysis (OR, 4.2; 95% CI, 2.14-8.23; P<0.001). The multivariable model indicated that categorical variables including owner recognition of jaundice (OR, 2.12; 95% CI, 1.19-3.77; P=0.011), concurrent hyperadrenocorticism (OR 1.94; 95% CI, 1.08-3.47; P=0.026), and Pomeranian breed (OR, 2.46; 95% CI 1.10-5.50; P=0.029) were associated with increased odds of death, and vomiting was associated with decreased odds of death (OR, 0.48; 95% CI, 0.30-0.72; P=0.001). Continuous variables in the multivariable model, total serum/plasma bilirubin concentration (OR, 1.03; 95% CI, 1.01-1.04; P<0.001) and age (OR, 1.17; 95% CI, 1.08-1.26; P<0.001), were associated with increased odds of death. The clinical utility of total serum/plasma bilirubin concentration as a biomarker to predict death was poor with a sensitivity of 0.61 (95% CI, 0.54-0.69) and a specificity of 0.63 (95% CI, 0.59-0.66). This study identified several prognostic variables in dogs with GBM including total serum/plasma bilirubin concentration, age, clinical signs, concurrent hyperadrenocorticism, and the Pomeranian breed. The presence of hypothyroidism or diabetes mellitus did not impact outcome in this study.

ACVIM consensus statement on the diagnosis and treatment of chronic hepatitis in dogs

This consensus statement on chronic hepatitis (CH) in dogs is based on the expert opinion of 7 specialists with extensive experience in diagnosing, treating, and conducting clinical research in hepatology in dogs. It was generated from expert opinion and information gathered from searching of PubMed for manuscripts on CH, the Veterinary Information Network for abstracts and conference proceeding from annual meetings of the American College of Veterinary Medicine and the European College of Veterinary Medicine, and selected manuscripts from the human literature on CH. The panel recognizes that the diagnosis and treatment of CH in the dog is a complex process that requires integration of clinical presentation with clinical pathology, diagnostic imaging, and hepatic biopsy. Essential to this process is an index of suspicion for CH, knowledge of how to best collect tissue samples, access to a pathologist with experience in assessing hepatic histopathology, knowledge of reasonable medical interventions, and a strategy for monitoring treatment response and complications.

Acute liver failure in two dogs following ingestion of cheese tree (Glochidion ferdinandi) roots

OBJECTIVE

To describe the management and resolution of acute liver failure (ALF) in two dogs following ingestion of cheese tree (Glochidion ferdinandi) roots.

CASE SUMMARIES

A 2-year-old male entire Bullmastiff and a 5-year-old female neutered German Shepherd dog were presented for acute-onset lethargy and vomiting after chewing on tree roots of a cheese tree. Both dogs developed clinical abnormalities consistent with ALF, including hepatic encephalopathy, marked increase in alanine aminotransferase activity and bilirubin concentration, and prolonged coagulation times. Treatment included administration of intravenous fluids, hepatoprotectants, vitamin K₁ , antibiotics, lactulose, antacids, antiemetics, and multiple fresh frozen plasma transfusions. Follow-up examinations performed 30 days after initial presentation revealed the dogs to be clinically healthy with serum biochemical and coagulation profiles within reference intervals.

NEW OR UNIQUE INFORMATION

This is the first report describing ALF in two dogs following ingestion of cheese tree (G. ferdinandi) roots. In this clinical setting, despite a poor prognosis, survival and recovery of adequate liver function were possible with medical management.

Cycad Palm Toxicosis in 14 Dogs from Texas

The goal of this study is to report clinical information, diagnostic findings, and treatment modalities; assess variables that may help distinguish survivors from nonsurvivors; and review the outcome of cycad palm toxicosis in dogs. Fourteen client-owned dogs with confirmed cycad palm ingestion were identified by reviewing the medical record database at Gulf Coast Veterinary Specialists. Information on signalment, time of ingestion to presentation, clinical signs, physical examination findings, initial and peak/nadir laboratory abnormalities, radiographic and ultrasonographic findings, treatment modalities, liver histopathology, and clinical outcome was retrieved. Of the 14 dogs, nine (64%) died as a direct result of cycad palm intoxication, and three survivors had persistently elevated liver enzymes, signifying residual liver damage. Despite decontamination, patients continued to display evidence of illness, indicating rapid absorption of toxins. When evaluating initial and peak/nadir laboratory values, nadir serum albumin levels and nadir platelet counts were significantly lower in nonsurvivors compared to survivors (1.25 g/dL [0.4–2.1 g/dL] versus 2.6 g/dL [1.7–3.4 g/dL] and 21 × 103 [0–64 × 103] versus 62 × 103 [6–144 × 103], respectively). In this cohort of dogs, the case fatality rate was higher than previously reported. Nadir serum albumin levels and nadir platelet counts may help distinguish potential survivors from nonsurvivors.

Acute Liver Injury and Failure

Acute liver injury and acute liver failure are syndromes characterized by a rapid loss of functional hepatocytes in a patient with no evidence of pre-existing liver disease. A variety of inciting causes have been identified, including toxic, infectious, neoplastic, and drug-induced causes. This article reviews the pathophysiology and clinical approach to the acute liver injury/acute liver failure patient, with a particular emphasis on the diagnostic evaluation and care in the acute setting.

Acute liver failure in dogs and cats

OBJECTIVE

To define acute liver failure (ALF), review the human and veterinary literature, and discuss the etiologies and current concepts in diagnostic and treatment options for ALF in veterinary and human medicine.

ETIOLOGY

In veterinary medicine ALF is most commonly caused by hepatotoxin exposure, infectious agents, inflammatory diseases, trauma, and hypoxic injury.

DIAGNOSIS

A patient may be deemed to be in ALF when there is a progression of acute liver injury with no known previous hepatic disease, the development of hepatic encephalopathy of any grade that occurs within 8 weeks after the onset of hyperbilirubinemia (defined as plasma bilirubin >50 μM/L [>2.9 mg/dL]), and the presence of a coagulopathy. Diagnostic testing to more specifically characterize liver dysfunction or pathology is usually required.

THERAPY

Supportive care to aid the failing liver and compensate for the lost functions of the liver remains the cornerstone of care of patients with ALF. Advanced therapeutic options such as extracorporeal liver assist devices and transplantation are currently available in human medicine.

PROGNOSIS

The prognosis for ALF depends upon the etiology, the degree of liver damage, and the response to therapy. In veterinary medicine, the prognosis is generally poor.