Anaphylaxis in dogs and cats

Occurrence of hemodynamic changes following administration of rocuronium in a dog presenting for an ophthalmic procedure

A 10-year-old, neutered male, Golden Retriever dog presented for surgical correction of a descemetocele. Acepromazine (0.02 mg/kg) and methadone (0.5 mg/kg) were administered intramuscularly for sedation, propofol (2 mg/kg) and midazolam (0.2 mg/kg) were administered intravenously for anaesthetic induction and isoflurane in oxygen was utilised for anaesthetic maintenance. Rocuronium (0.5 mg/kg), a neuromuscular blocking agent, was administered intravenously to facilitate central positioning of the eye for surgery. Within 10 min of rocuronium administration, the dog became tachycardic and hypotensive. Hemodynamic aberrations did not resolve with initial interventions but were successfully mitigated with the administration of diphenhydramine (0.8 mg/kg) intravenously. The dog remained stable throughout the remainder of the procedure and experienced a smooth and uneventful recovery. While it is difficult to confirm that the hemodynamic changes observed in this clinical case resulted solely from administration of rocuronium, the observance of the cardiovascular changes, timing of events and response to therapy suggest that rocuronium elicited a histamine response that was successfully treated with diphenhydramine.

Recurrent episodes of oral mite anaphylaxis in a dog

OBJECTIVE

To describe the clinical presentation and response to management of a dog with presumed oral mite anaphylaxis.

CASE SUMMARY

A 2-year-old male intact Golden Retriever was evaluated for a history of recurrent anaphylactic episodes. Over a period of 19 months, the dog had a total of 8 anaphylactic episodes that occurred in 2 different residences within the same state. The episodes most commonly resulted in vomiting and labored breathing, but the dog developed ascites, hypotension, and gall bladder wall edema during the most severe episodes. Serological testing demonstrated high immunoglobulin E levels to storage mites (SMs), specifically Tyrophagus SM. The dog's kibble was transitioned to being stored in small quantities in airtight containers in the freezer. At the time of publication, the dog has not had an anaphylactic reaction since making this change 1 year ago.

NEW OR UNIQUE INFORMATION PROVIDED

Based on a literature search and to the best of the authors' knowledge, this is the first time that SMs have been associated with severe recurrent anaphylaxis in a dog.

Acute hepatic rupture causing hemoperitoneum in a dog with anaphylaxis

A 2-year-old spayed female Siberian Husky was presented with a history of acute onset lethargy, collapse, haematochezia and vomiting. The patient was severely tachycardic and hypotensive. Point-of-care ultrasound revealed gallbladder wall thickening and peritoneal effusion consistent with haemorrhage on subsequent abdominocentesis. Despite attempted medical stabilization over the course of several hours, including blood products and multiple autotransfusions, the patient progressed to cardiopulmonary arrest. The dog was successfully resuscitated but was subsequently euthanized. Necropsy revealed a severe, acute hemoperitoneum secondary to rupture of the left lateral liver lobe. A tear in the hepatic capsule was identified along with a large hematoma. A single adult nematode, consistent with Dirofilaria immitis, was found in a pulmonary vessel in the right caudal lung lobe. The remaining necropsy findings were supportive of the clinical diagnosis of anaphylaxis. This report details a case, with necropsy findings, supporting a diagnosis of anaphylaxis and severe, refractory hemoperitoneum resulting from hepatic rupture. Acute hepatic rupture should be considered in cases of anaphylaxis-related hemoperitoneum.

Modified rush venom immunotherapy in dogs with Hymenoptera hypersensitivity

BACKGROUND

Hymenoptera envenomation occurs frequently in people and dogs and can trigger anaphylaxis. Venom immunotherapy (VIT) is the only preventive treatment for Hymenoptera hypersensitivity and is indicated for people with severe adverse reactions to insect stings. Rush VIT is an accelerated VIT protocol in people. This has not been reported in dogs.

OBJECTIVES

The objective of the study was to evaluate the safety of modified rush VIT.

ANIMALS

Twenty client-owned dogs with Hymenoptera hypersensitivity based on a history of adverse reactions to Hymenoptera envenomation and a positive intradermal test to honey bee and/or paper wasp venom.

MATERIALS AND METHODS

Dogs received incremental doses of venom via subcutaneous injection one day per week for three consecutive weeks until the maintenance dose was achieved. Vital signs were recorded every 30 min prior to venom administration. Adverse reactions were categorised as localised or grade I-IV systemic reactions.

RESULTS

Nineteen of 20 dogs (95%) completed rush VIT. One dog experienced a grade III systemic adverse reaction and was withdrawn from the study. No adverse reactions occurred in 10 of 20 dogs (50%). Localised and grade I-II systemic reactions occurred in nine of 20 dogs (45%), including nausea (n = 5), injection site pruritus (n = 3) and diarrhoea and lethargy (n = 1).

CONCLUSIONS AND CLINICAL RELEVANCE

Modified rush VIT in dogs was well-tolerated and should be considered for dogs with Hymenoptera hypersensitivity. Larger studies are needed to evaluate the efficacy of VIT in dogs for preventing hypersensitivity reactions to insect stings.

Evaluation of hemostatic derangements associated with canine anaphylaxis and the relationship to syndrome severity

OBJECTIVE

To describe hemostatic derangements associated with canine anaphylaxis and to assess for association with syndrome severity.

DESIGN

Prospective observational study.

SETTING

University teaching hospital.

ANIMALS

Twenty-seven client-owned dogs, recruited from November 2018 to January 2022, diagnosed with anaphylaxis of varying severity were included. Study inclusion required presentation <6 hours after initiation of clinical signs, no medications or history of illness within the prior 2 weeks, lack of comorbidities expected to affect hemostasis, and lack of a disease state that could alternatively explain the clinical presentation.

INTERVENTIONS

Blood samples were collected within the first hour of presentation for CBC, serum biochemistry, prothrombin time (PT), activated partial thromboplastin time (aPTT), and viscoelastic coagulation testing for use with a cartridge-based point-of-care device.

MEASUREMENTS AND MAIN RESULTS

Clotting time and clot formation time were prolonged, alpha angle and maximum clot firmness were decreased, PT and aPTT were prolonged, and platelet counts were lower in severe cases compared to mild and moderate cases. There were no differences for any parameter between mild and moderate cases. The presence or absence of abdominal effusion was not associated with hemostatic status.

CONCLUSIONS

Global hemostatic derangements consistent with hypocoagulability are a prominent feature of severe anaphylaxis in dogs and should be considered for routine evaluation.

Simultaneous hypersensitivity reactions to trimethoprim-sulfamethoxazole and amoxicillin-clavulanate in a dog

Antibiotics are known to be able to cause hypersensitivity reactions through various mechanisms. We present a case of drug-induced immune thrombocytopenia (DITP) and anaphylactic shock occurring simultaneously in a dog after the administration of two classes of antibiotics, namely trimethoprim-sulfamethoxazole (TMP-SMX) and amoxicillin-clavulanate (AMC). The patient recovered completely from DITP on discontinuation of TMP-SMX and the anaphylactic shock caused by AMC was treated with intensive care. DITP is a rare adverse drug reaction (ADR), and anaphylactic shock is a life-threatening ADR. This is the first case report of a dog manifesting two types of hypersensitivity reactions caused by two antibiotics.

The safety of rush immunotherapy in the management of canine atopic dermatitis-230 cases

BACKGROUND

The duration of the induction phase of allergen-specific immunotherapy conventionally is a period of several weeks, during which the volume of an allergen solution, administered by injection, is gradually increased until the maintenance dose is reached. In rush immunotherapy (RIT), the induction period is abbreviated to achieve a faster improvement in clinical signs of atopic dermatitis (AD) compared to conventional immunotherapy.

OBJECTIVE

The aim of this retrospective study was to evaluate the safety of RIT in 230 dogs with AD and report any adverse effects (AE).

ANIMALS

Two hundred thirty client-owned dogs.

MATERIALS AND METHODS

Medical records of dogs receiving RIT between 2012 and 2021 were analysed and observed AE were investigated. All dogs underwent RIT following a protocol of subcutaneous allergen extract injections, given hourly with an incrementally increasing volume from 0.1 to 1.0 mL.

RESULTS

Adverse effects were documented in 6 of 230 (2.6%) dogs. Five of these dogs (2.2%) showed mild gastrointestinal signs (1 of 5 vomiting, 4 of 5 diarrhoea) and one patient an increase in body temperature by 1.5°C. These occurred at different stages of the RIT protocol. All AE were graded as mild and self-limiting.

CONCLUSIONS AND CLINICAL RELEVANCE

Based on these data, supervised RIT in dogs appears to be a safe procedure to achieve the maintenance dose of allergen immunotherapy earlier with infrequent and mild AE.

Retrospective evaluation of hypersensitivity reactions and anaphylaxis in dogs (2003-2014): 86 cases

OBJECTIVE

To characterize anaphylactic reactions in dogs, including clinical signs, severity, treatments, prognosis, and estimated incidence. To determine whether glucocorticoids influence clinical recovery and survival.

DESIGN

Retrospective study between January 1, 2003 and April 28, 2014.

SETTING

University teaching hospital.

ANIMALS

Eighty-six dogs treated for a type I hypersensitivity reaction. Nineteen dogs fulfilled the criteria for anaphylaxis, and 67 dogs had mild cutaneous reactions.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The estimated incidence was 0.04% for anaphylaxis and 0.15% for mild hypersensitivity reactions. The female:male ratio (2.3:1) was significantly higher (P = 0.032) compared to our source population (ratio of 1:1.158). Vaccines were the most frequent trigger for anaphylaxis (57.9%) and mild hypersensitivity reactions (28.4%). Seventy-four (86%) dogs had cutaneous signs, and 11 (57.9%) dogs with anaphylaxis had no cutaneous signs reported. Forty-two (48.8%) dogs received both an H1 antagonist and a glucocorticoid, 34 (39.5%) dogs received an H1 antagonist only, and 6 (6.9%) dogs received a glucocorticoid only. The majority of the dogs survived, and 1 was euthanized due to complications. Clinical signs associated with nonsurvival included respiratory signs (P = 0.006), particularly respiratory distress (P < 0.00001) and cyanosis (P < 0.00001), and circulatory shock (P = 0.005). The analysis of the interaction between etiology, clinical signs, treatment, and outcome did not show any association between pairs of variables.

CONCLUSIONS

In the current study, anaphylaxis had a relatively good prognosis, and cutaneous signs were not always present. Based on the present data, the use of glucocorticoids to treat mild type I hypersensitivity reactions and anaphylaxis in dogs was not associated with clinical improvement or survival.

Retrospective review of diphenhydramine vs diphenhydramine plus glucocorticoid for the treatment of allergic reaction in cats

OBJECTIVES

The aims of the present study were to report the outcomes of treating allergic reactions in cats with diphenhydramine vs diphenhydramine plus glucocorticoid and to determine whether signs recurred or additional veterinary intervention was needed in the days after initial treatment.

METHODS

This retrospective study evaluated 73 cats treated for allergic reaction with diphenhydramine alone or in combination with a glucocorticoid at a 24 h emergency and specialty referral veterinary hospital between 1 January 2012 and 31 March 2021.

RESULTS

In total, 44 cats were treated with diphenhydramine alone, and 29 were treated with diphenhydramine plus dexamethasone sodium phosphate. The inciting cause was known or highly suspected in 50 patients. Vaccines were the most common (31 patients), followed by insect envenomation (17 cases). No cat in either group progressed to anaphylaxis. There was no difference in resolution of clinical signs between the groups. Follow-up contact was successfully made with 40/73 cat owners. All 40 cats were alive. Eight had persistent signs. There was no difference in the number of cats with persistent signs between groups. Five cats required additional treatment after the initial emergency visit. There was no difference between the two groups for persistent signs at follow-up.

CONCLUSIONS AND RELEVANCE

There was no difference in measured outcomes between cats treated with diphenhydramine alone vs those treated with a glucocorticoid in addition to diphenhydramine in this population. The ideal treatment for allergic reactions is unknown. Based on currently available data in human and veterinary literature, glucocorticoids are not indicated to treat acute allergic reactions. The role of antihistamines as part of a symptomatic supportive treatment plan to shorten the duration of signs is unclear at this time and may be considered.

A Retrospective Evaluation of Snake Envenomation in Dogs in South Korea (2004-2021)

Snake envenomation is a medical emergency capable of causing local and systemic complications. However, information on venomous snakebite in dogs in South Korea is scarce. In this study, fifty-nine dogs treated at a private veterinary clinic from 2004 to 2021 were retrospectively studied. The aim was to characterize the demographics, elapsed time between snakebite and veterinary clinic presentation, laboratory findings, clinical signs, treatments, adverse reactions to antivenom, and prognosis of venomous snakebite. Snakebite was mostly observed between 12 p.m. and 5 p.m. from April to October. On the days of envenomation, the weather conditions were mostly cloudy, followed by rain/precipitation, and least frequently fair weather. Grassland was the most common incident location, and leashed dog walking was the most frequent activity when snakebite occurred. The main local symptoms were edema, hemorrhagic discharge, cutaneous erythema, ulceration, and necrosis. Major systemic clinical signs were tachypnea, tachycardia, altered mentation, ptyalism, and hypotension. Based on the time interval between snakebite and presentation at the veterinary clinic, two groups were defined: <4 h (Group 1, 49.2%) and ≥4 h (Group 2, 50.8%). Systemic inflammation was more frequently observed in Group 2. The level of C-reactive protein at presentation (p = 0.036) and the highest-level during hospitalization (p = 0.023) were significantly elevated in Group 2 (≥4 h). The dogs in Group 2 displayed more frequent muscle damage (increased creatine kinase) than the dogs in Group 1, and a higher level of creatine kinase was associated with delayed (≥4 h) presentation after snakebite (p = 0.003). All of the dogs were treated symptomatically, and 34 dogs (58%) received antivenom. Treatment with antivenom showed no adverse reactions in this study. All of the treated dogs recovered. One dog was euthanized without any treatment due to respiratory distress, hypotension, and cost constraints. In conclusion, this study provides baseline information on venomous snakebite in dogs in South Korea. The prognosis was excellent, especially when the dogs were treated within 4 h.

Allergy, inflammation, hepatopathy and coagulation biomarkers in dogs with suspected anaphylaxis due to insect envenomation

Objectives

To compare concentrations of biomarkers of; allergy [mast cell tryptase (MCT) and histamine], inflammation [interleukin (IL)-6,-10, and-18, CXCL8, CCL2, keratinocyte chemoattractant (KC), C-reactive protein (CRP)], endothelial glycocalyx shedding (hyaluronan), coagulation [prothrombin time, activated partial thromboplastin time, fibrinogen concentration, and von Willebrand Factor antigen, protein C (PC) and antithrombin (AT) activity], and hepatopathy [alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and total bilirubin] between dogs with anaphylaxis after suspected insect exposure, dogs with critical illness, and healthy dogs.

Design

This was a single center prospective clinical observational comparative biomarker study that included 25 dogs with anaphylaxis (evidence of insect exposure, acute dermatological signs, and other organ involvement), 30 dogs with other critical illness, and 20 healthy dogs. Differences across groups in biomarker concentrations were tested using one-way ANOVA or Kruskal-Wallis test, with significant P values (<0.05) reported for pairwise differences detected by post-hoc tests. Logistic regression models were used to calculate the area under the receiver operator characteristic curve (AUROC) for discrimination between anaphylaxis and non-anaphylactic illness.

Results

Histamine concentration was significantly higher in the anaphylaxis group than the healthy (P < 0.001) and critically ill groups (P < 0.001), whereas no differences in MCT were detected amongst groups. Biomarker concentrations that were increased relative to healthy dogs in both the anaphylaxis and critically ill groups included IL-10 (P < 0.001 and P = 0.007, respectively), CCL2 (P = 0.007 and P < 0.001, respectively) and AST (both P < 0.001), whereas only the critically ill group had significantly increased CRP (P < 0.001), IL-6 (P < 0.001), KC (P < 0.001), ALP (P < 0.001), and fibrinogen (P = 0.016) concentrations, compared to the healthy group. Only dogs with anaphylaxis had significantly higher hyaluronan (P = 0.021) and ALT (P = 0.021) concentrations, and lower PC (P = 0.030) and AT (P = 0.032) activities, compared to healthy dogs. Both CRP and histamine concentration showed good discrimination between anaphylaxis and other critical illness, with an AUROC of 0.96 (95% CI 0.91-1) and 0.81 (95% CI 0.69-0.93), respectively.

Conclusions

This preliminary study in dogs with anaphylaxis after suspected insect exposure, found evidence of an early innate immune response, glycocalyx shedding and anticoagulant consumption. Both CRP and histamine showed potential clinical utility for differentiation between anaphylaxis and other critical illness.

The influence of leukoreduction on the acute transfusion-related complication rate in 455 dogs receiving 730 packed RBCs: 2014-2017

OBJECTIVE

To investigate the influence of prestorage leukoreduction of packed RBCs (pRBCs) on acute transfusion-related complication rate in dogs.

SETTING

Two private referral hospitals.

DESIGN

Retrospective case study.

ANIMALS

Four hundred and fifty-five dogs receiving nonleukoreduced (nLR) or leukoreduced (LR) pRBC between January 1, 2014 and July 31, 2017.

MEASUREMENTS AND MAIN RESULTS

Transfusions were retrospectively reviewed to record data about the patient, donor, unit, transfusion event, acute complications, hospital discharge, and cause of death. Of 730 transfusion events in 455 dogs, 288 used LR pRBC and 442 used nLR pRBC. There was a 18.9% (138/730) overall complication rate. Seven (0.96%) complications were life-threatening. The most common complications were pyrexia (5.6%), gastrointestinal signs (4.9%), and hemolysis with no other signs (4.1%). Pyrexia with no other clinical signs, consistent with a febrile nonhemolytic transfusion reaction (FNHTR), occurred in 3.2% of transfusion events. There was a significant (P = 0.03) decrease in the rate of FNHTR with LR pRBC (1%) versus nLR pRBC (4.5%). Use of LR pRBC did not decrease in-hospital mortality. The odds of any complication, hemolysis only, FNHTR, and more severe complications increased with pRBC age. Leukoreduction did not decrease the impact of pRBC age on these complications. Use of older pRBC did not increase the incidence of life-threatening complications or mortality. Dogs receiving pRBC for blood loss were more likely to have gastrointestinal and more severe complications than those dogs that had hemolysis. The effect of pRBC unit age on complications was not influenced by the underlying reason for transfusion. Dogs that received a previous transfusion were more likely to have respiratory complications.

CONCLUSION

In this study, the use of LR pRBC was associated with a decreased rate of FNHTR but no other complications. Unit age was associated with the incidence of hemolysis, FNHTR, and complication severity but not the rate of life-threatening complications or mortality.

Effects of morphine on histamine release from two cell lines of canine mast cell tumor and on plasma histamine concentrations in dogs with cutaneous mast cell tumor

OBJECTIVE

To determine the effects of morphine on histamine release from 2 canine mast cell tumor (MCT) cell lines and on plasma histamine concentrations in dogs with cutaneous MCTs.

ANIMALS

10 dogs with cutaneous MCT and 10 dogs with soft tissue sarcoma (STS).

PROCEDURES

The study consisted of 2 phases. First, 2 canine MCT cell lines were exposed to 3 pharmacologically relevant morphine concentrations, and histamine concentrations were determined by an ELISA. Second, dogs with MCT or STS received 0.5 mg of morphine/kg, IM, before surgery for tumor excision. Clinical signs, respiratory rate, heart rate, arterial blood pressure, rectal temperature, and plasma histamine concentrations were recorded before and 5, 15, 30, and 60 minutes after morphine administration but prior to surgery. Data were compared by use of a 2-way ANOVA with the Sidak multiple comparisons test.

RESULTS

In the first phase, canine MCT cell lines did not release histamine when exposed to pharmacologically relevant morphine concentrations. In the second phase, no differences were noted for heart rate, arterial blood pressure, and rectal temperature between MCT and STS groups. Plasma histamine concentrations did not significantly differ over time within groups and between groups.

CONCLUSIONS AND CLINICAL RELEVANCE

No significant changes in histamine concentrations were noted for both in vitro and in vivo study phases, and no hemodynamic changes were noted for the in vivo study phase. These preliminary results suggested that morphine may be used safely in some dogs with MCT.

Anaphylaxis after vaccination for cats in Japan

Severe adverse reactions in cats after vaccination were examined from 316 cases reported to the Ministry of Agriculture, Forestry and Fisheries (MAFF) in Japan during 15-year period from April 2004 to March 2019. We found that 130 (41%) showed anaphylaxis, and 99 (76%) of the 130 cases of anaphylaxis resulted in death. Veterinarians should be well prepared to deal with vaccine-associated anaphylaxis in cats. Bovine serum albumin (BSA) as indicator of purification was detected at high levels in commercially available feline vaccines. BSA might derive from fetal calf serum in culture media. This study provides useful information about anaphylaxis including critical details of the potential clinical signs associated with adverse events to feline vaccination.

Clinical characteristics of two-hundred thirty-two dogs (2006-2018) treated for suspected anaphylaxis in Perth, Western Australia

OBJECTIVE

To describe the clinical features of dogs treated for suspected anaphylaxis in Perth, Western Australia.

DESIGN

Single-centre observational case series with retrospective and prospective phases.

METHODS

This was a two-phase study of dogs with clinical suspicion of anaphylaxis presenting to the emergency service of a university teaching hospital. Dogs required evidence of, and appropriate treatment of, a type 1 hypersensitivity reaction as well as two or more organs affected (or cardiovascular signs alone) to be included. Phase 1 includes retrospective case series of 186 dogs (March 2006-December 2018). Phase 2 includes prospective descriptive case series of 46 dogs (October 2017-July 2018) focused on clinical signs.

RESULTS

In phase 1, 88 (47%) dogs had evidence of insect exposure prior to the acute event. One hundred forty (75%) dogs had dermatological signs, 141 (76%) had gastrointestinal signs and 129 (69%) had cardiovascular signs. Ninety-two (49%) dogs had vasoconstrictive shock (5 with bradycardia), 24 (13%) had vasodilatory shock, 8 (4%) had mixed vasodilatory and vasoconstrictive shock and 5 (3%) had unclassifiable shock. On focused abdominal ultrasound, 42 of 71 (59%) dogs had gallbladder wall oedema and 3 of 71 (4%) dogs had peritoneal free fluid. In phase 2, the distributions of insect exposure, organ dysfunction and sonographic abnormalities were similar to phase 1.

CONCLUSION

Dogs presenting with suspected anaphylaxis showed a broad range of presentations. Dermatological signs were absent in a proportion of dogs, vasoconstrictive shock was more frequent than vasodilatory and unique features of shock were identified. This study highlights the challenges of diagnosis based on presenting features alone.

Investigation of the association between gall bladder wall thickness and hypoalbuminaemia in dogs

OBJECTIVES

To assess the correlation between gallbladder wall thickness and serum/plasma albumin concentrations in dogs.

MATERIALS AND METHODS

Retrospective searches of digital medical record databases were conducted to identify dogs that had either severely low serum/plasma albumin concentration (<1.5 g/dL) or ultrasonographic evidence of gallbladder wall thickening (>2 mm). Analysis of covariance models were used to analyze gallbladder wall thickness with sample type (serum vs plasma), age, etiology, albumin, and albumin ' etiology as the covariates.

RESULTS

A total of 216 dogs met inclusion criteria. One-hundred and forty-six dogs had a thickened gallbladder wall (Group 1). Median serum/plasma albumin concentration for dogs in this group was 2.2 g/dL (1 to 5 g/dL), and 84 dogs (57.5%) had hypoalbuminemia (<2.5 g/dL). The search for dogs with severe hypoalbuminemia (< 1.5 g/dL) identified 70 dogs (Group 2). In this group, median gallbladder wall thickness was 1.3 mm (0.2 to 6.1 mm) and 17 dogs (24.3%) had a thickened gallbladder wall. Serum/plasma albumin concentration and gallbladder wall thickness were not significantly correlated for Group 1 (r = 0.0044, p = 0.9580) or Group 2 (r = -0.1137, p = 0.3487). A moderate negative correlation (-0.64) was identified between gallbladder wall thickness and albumin concentration in dogs with immune-mediated diseases (p = 0.03).

CLINICAL SIGNIFICANCE

Gallbladder wall thickness and serum/plasma albumin concentration are independent variables in dogs.

Randomized double-blinded clinical trial on acute transfusion reactions in dogs receiving leukoreduced versus nonleukoreduced packed red blood cells

Background

Leukoreduction of blood products is commonly performed in human medicine, but its effect on outcome or incidence of transfusion reactions (TRs) in dogs is unknown.

Objectives

To prospectively evaluate the incidence of acute TRs in, and the outcome of, dogs receiving either leukoreduced (LR) or nonleukoreduced (N‐LR) packed red blood cells (PRBC).

Animals

Dogs (n = 194) administered PRBC between August 2017 and June 2020.

Methods

Prospective randomized double‐blinded clinical trial. Dogs were randomized to receive either LR or N‐LR PRBC and clinicians, nurses and investigators were blinded to the group allocations. The incidence of TRs, change in PCV, hospitalization duration, and survival to discharge were recorded.

Results

Out of the 194 dogs, 96 received LR and 98 received N‐LR PRBCs. The mean 12‐hour change in PCV value was +9.22% (SD 5.27%) for dogs that received N‐LR and +10.69% (SD 6.44%) for dogs that received LR PRBC (effect size 0.26, 95% confidence interval [CI] −0.02 to 0.55), which was not significantly different (P = .08). TRs were documented in 16/194 (8.24%) dogs, with 1/194 (0.51%) being a mild allergic reaction, while 15/194 (7.73%) had suspected febrile nonhemolytic TRs (FNHTRs). FNHTR incidence was not significantly different between the LR (6/96, 6.25%, 95% CI 2.8‐13.56) and N‐LR (9/98, 9.18%, 95% CI 4.92‐17.11) groups (P = .81). Of the 156 dogs that survived to discharge, 80/156 received N‐LR PRBC and 76/156 received LR PRBC which was not significantly different (P = .66).

Conclusions and Clinical Importance

A clinical advantage of using LR over N‐LR PRBC in terms of TRs and increase in PCV after transfusion was not detected.

A Suspected Anaphylactoid Reaction to Propofol in a Dog

Anaphylactoid reactions to anaesthetic drugs are rarely reported in veterinary medicine. The aim of this report is to describe a suspected anaphylactic reaction to propofol in a 14 years old Shih-Tzu undergoing general anaesthesia for ovariohysterectomy due to a pyometra. The anesthetic protocol included intramuscular methadone for premedication and fentanyl, midazolam and propofol intravenously for co-induction. At endotracheal intubation, the glottis appeared subjectively thickened. Shortly after induction and endotracheal intubation, desaturation, hypercapnia and bradycardia occurred; chest compliance at manual ventilation was poor and peripheral pulses were weak. The procedure was aborted. Pulmonary oedema was diagnosed at thoracic radiography and a cardiogenic origin was excluded via echocardiography. Fluid therapy and glucocorticoids were administered, and mechanical ventilation was started in the intensive care unit. Two hours later, the owner opted for euthanasia due to financial constraints.

Spontaneous abdominal effusion in dogs with presumed anaphylaxis

OBJECTIVE

To describe patient characteristics of dogs developing spontaneous abdominal effusion in association with anaphylaxis.

DESIGN

Retrospective study between 2010 and 2018.

SETTING

University teaching hospital and referral specialty private practice emergency departments.

ANIMALS

Sixteen dogs presenting to the emergency department for clinical signs suggestive of anaphylaxis with peritoneal effusion documented via ultrasonography.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Dogs presented with clinical signs of anaphylaxis including vomiting 12 of 16 (75%), diarrhea 9 of 16 (56%), and collapse 7 of 16 (44%). Physical examination findings included altered mentation 14 of 16 (88%), erythema 2 of 16 (13%), and urticaria 2 of 16 (13%). Historically, 3 of 16 (19%) had just recently been vaccinated, 1 of 16 (6%) had known contact with an insect, and 8 of 16 (50%) had been outdoors prior to the onset of clinical signs, whereas 5 of 16 (31%) had no known triggering event. At presentation, median systolic arterial pressure was 70 mm Hg (range, 30-210 mm Hg). Venous blood gas revealed an acidemia with a mean pH of 7.24 ± 0.09, a base deficit of 7.15 ± 7.7 mmol/L, and an increased plasma lactate with a mean of 7.35 ± 2.09 mmol/L. Bloodwork abnormalities included an increased alanine aminotransferase activity with a mean of 439.2 ± 404.5 U/L and an increased gamma-glutamyl transferase activity with a mean concentration of 7.29 ± 4.1 U/L. Twelve patients (75%) had gallbladder wall abnormalities on ultrasonography. Eight patients (50%) had abdominocentesis performed. The median PCV of the effusion was 0.29 L/L (29%; range, 4-41) and total plasma protein was 38 g/L (3.8 g/dL; range, 2.4-6.5). Two dogs (12.5%) were euthanized. The remaining 14 dogs (87.5%) survived to discharge, with a mean hospitalization time of 23.7 ± 16.7 hours.

CONCLUSIONS

Abdominal effusion should be considered a potential sequela of anaphylaxis in dogs. Therefore, serial monitoring for presence or development of spontaneous abdominal effusion should be considered.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) Transfusion Reaction Small Animal Consensus Statement (TRACS). Part 1: Definitions and clinical signs

OBJECTIVE

To use a systematic, evidence-based consensus process to develop definitions for transfusion reactions in dogs and cats.

DESIGN

Evidence evaluation of the literature was carried out for identified transfusion reaction types in dogs and cats. Reaction definitions were generated based on synthesis of human and veterinary literature. Consensus on the definitions was achieved through Delphi-style surveys. Draft recommendations were made available through industry specialty listservs and comments were incorporated.

RESULTS

Definitions with imputability criteria were developed for 14 types of transfusion reactions.

CONCLUSIONS

The evidence review and consensus process resulted in definitions that can be used to facilitate future veterinary transfusion reaction research.

Retrospective review of diphenhydramine versus diphenhydramine plus glucocorticoid for treatment of uncomplicated allergic reaction in dogs

OBJECTIVE

To report the outcome of treatment of uncomplicated allergic reactions in dogs with diphenhydramine vs diphenhydramine plus glucocorticoid and to determine the incidence rate of uncomplicated allergic reactions DESIGN: Retrospective study between January 1, 2012 and August 15, 2018.

SETTING

Privately owned, 24-hour emergency and specialty referral veterinary hospital.

ANIMALS

Eight hundred and eighty cases of dogs treated for uncomplicated allergic reaction with diphenhydramine alone or in combination with a glucocorticoid.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two hundred ninety-nine dogs were treated with diphenhydramine alone, and 581 were treated with diphenhydramine plus Dex SP. There was no difference between the 2 groups for response to initial therapy, need for additional veterinary intervention after discharge, or persistent signs at follow-up. The cumulative incidence of emergency department presentation for uncomplicated allergic reaction in this hospital was 1.2%.

CONCLUSIONS

There was no difference in measured outcomes between dogs treated with diphenhydramine alone vs those treated with a glucocorticoid in addition to diphenhydramine in this population of dogs.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) transfusion reaction small animal consensus statement (TRACS). Part 3: Diagnosis and treatment

OBJECTIVE

To systematically review available evidence to develop guidelines for diagnosis and treatment of transfusion-associated reactions in dogs and cats.

DESIGN

Standardized and systemic evaluation of the literature (identified through Medline via PubMed and Google Scholar searches) was carried out for identified transfusion reaction types in dogs and cats. The available evidence was evaluated using PICO (Population, Intervention, Comparison, Outcome) questions generated for each reaction type. The evidence was categorized by level of evidence (LOE) and quality (Good, Fair, or Poor). Guidelines, diagnostic, and treatment algorithms were generated based on the evaluation of the evidence. Consensus on the final guidelines was achieved through Delphi-style surveys. Draft recommendations were disseminated through veterinary specialty listservs for review and comments, which were evaluated and integrated prior to final publication.

RESULTS

Medline via PubMed and Google Scholar databases were searched. There were 14 Population Intervention Comparison Outcome questions identified and corresponding worksheets were developed focusing on the diagnosis and treatment of transfusion-associated reactions in dogs and cats. Fourteen guidelines and four algorithms were developed with a high degree of consensus.

CONCLUSIONS

This systematic evidence evaluation process yielded recommended diagnostic and treatment algorithms for use in practice. However, significant knowledge gaps were identified, demonstrating the need for additional research in veterinary transfusion medicine.

Adverse consequences of vaccination

The importance of adverse effects from vaccination must not be overstated. Vaccine benefits greatly exceed any risks from the procedure. Neither must they be minimized. Unnecessary vaccination must be discouraged. Hypersensitivity reactions to vaccine components are real and must be guarded against. Residual virulence, although a concern tends to be more a hypothetical than a real problem. Progressive improvements in animal vaccines have significantly reduced the chances of adverse effects occurring, although some issues persist. One such example is injection-site sarcomas in cats. Another issue is the influence of animal size on the prevalence of adverse events in dogs.

Mortality rate and prognostic factors for dogs with severe anaphylaxis: 67 cases (2016-2018)

OBJECTIVE

To determine mortality rates for dogs with severe anaphylaxis and identify potential prognostic factors.

ANIMALS

67 dogs with suspected anaphylaxis graded as severe.

PROCEDURES

Dogs were classified on the basis of outcome as survivors and nonsurvivors. Medical records were reviewed, and data were extracted including signalment, examination findings, time to hospital admission from onset of clinical signs, CBC results, serum biochemical analysis results, coagulation testing results, and findings on abdominal ultrasonography. Initial treatment within the first 6 hours after hospital admission was recorded for analysis, specifically including the use of epinephrine, diphenhydramine, corticosteroids, antimicrobials, fresh-frozen plasma, and supplemental dextrose.

RESULTS

The overall mortality rate was 14.9% (10/67) for dogs with anaphylaxis graded as severe. Serum phosphorus concentration and prothrombin time (PT) were significantly higher in nonsurvivors, compared with survivors. Nonsurvivors had lower presenting body temperatures than survivors. Serum phosphorus concentration ≥ 12.0 mmol/L, hypoglycemia within 6 hours after hospital admission, high PT value, concurrently high PT and partial thromboplastin time (PTT) values > 50% above the reference range limit, and the need for supplemental dextrose were associated with death. The incidences of coagulopathy and peritoneal effusion were unexpectedly high (85.2% and 65.5% of dogs, respectively) but were not indicative of survival.

CONCLUSIONS AND CLINICAL RELEVANCE

Despite the poor presenting clinical condition seen in dogs with severe anaphylaxis, the rate of survival with treatment was fairly high. Coagulopathy and the presence of peritoneal effusion were common findings in dogs with severe anaphylaxis. Serum phosphorus concentration ≥ 12.0 mmol/L, high PT value, concurrent increases of PT and PTT values > 50% above reference range limits, hypoglycemia within 6 hours after hospital admission, and the need for supplemental dextrose were associated with death.

Anaphylaxis-related hemoperitoneum in 11 dogs

OBJECTIVE

To describe the unique complication of hemoperitoneum associated with anaphylaxis.

DESIGN

Retrospective case series from September 2012 to August 2017.

SETTING

Two private emergency and specialty referral hospitals.

ANIMALS

Eleven client-owned dogs diagnosed with anaphylaxis and hemoperitoneum upon presentation or referral.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Inclusion criteria included clinical signs consistent with anaphylaxis (hypotension, tachycardia, vomiting, diarrhea, weakness, collapse, with or without the presence of dermal signs) due to witnessed or unwitnessed presumed bee sting, an elevated alanine aminotransferase (ALT), performance of abdominal FAST (AFAST) examination with an abdominal fluid score, the sonographic presence of gallbladder wall edema, and hemoperitoneum. All dogs (n=11) were managed medically without surgical intervention. 91% (n=10) of dogs survived to discharge.

CONCLUSIONS

Hemoperitoneum development can be seen with anaphylactic reactions, though the exact mechanism remains to be fully understood. Medical therapy is warranted and can be successful in these patients; surgery is not indicated to address hemoperitoneum.

Plasma histamine concentrations in horses administered sodium penicillin, guaifenesin-xylazine-ketamine and isoflurane with morphine or butorphanol

OBJECTIVE

Various drugs administered to horses undergoing surgical procedures can release histamine. Histamine concentrations were evaluated in horses prepared for surgery and administered butorphanol or morphine intraoperative infusions.

STUDY DESIGN

Prospective studies with one randomized.

ANIMALS

A total of 44 client-owned horses.

METHODS

In one study, anesthesia was induced with xylazine followed by ketamine-diazepam. Anesthesia was maintained with guaifenesin-xylazine-ketamine (GXK) during surgical preparation. For surgery, isoflurane was administered with intravenous (IV) morphine (group M: 0.15 mg kg^-1 and 0.1 mg kg^-1 hour^-1; 15 horses) or butorphanol (group B: 0.05 mg kg^-1 and 0.01 mg kg^-1 hour^-1; 15 horses). Histamine and morphine concentrations were measured using enzyme-linked immunoassay before opioid injection (time 0), and after 1, 2, 5, 30, 60 and 90 minutes. In a subsequent study, plasma histamine concentrations were measured in 14 horses before drug administration (baseline), 15 minutes after IV sodium penicillin and 15 minutes after starting GXK IV infusion. Statistical comparison was performed using anova for repeated measures. Pearson correlation compared morphine and histamine concentrations. Data are presented as mean ± standard deviation. Significance was assumed when p ≤ 0.05.

RESULTS

With histamine, differences occurred between baseline (3.2 ± 2.4 ng mL^-1) and GXK (5.2 ± 7.1 ng mL^-1) and between baseline and time 0 in group B (11.9 ± 13.4 ng mL^-1) and group M (11.1 ± 12.4 ng mL^-1). No differences occurred between baseline and after penicillin or between groups M and B. Morphine concentrations were higher at 1 minute following injection (8.1 ± 5.1 ng mL^-1) than at 30 minutes (4.9 ± 3.1 ng mL^-1) and 60 minutes (4.0 ± 2.5 ng mL^-1). Histamine correlated with morphine at 2, 30 and 60 minutes.

CONCLUSIONS AND CLINICAL RELEVANCE

GXK increased histamine concentration, but concentrations were similar with morphine and butorphanol.

ST segment depression and ventricular fibrillation in a dog after contrast agent administration

An 11-year-old Toy Poodle underwent a computed tomography examination with contrast (iohexol) enhancement under anesthesia. Heart rate and R-wave amplitude on electrocardiogram (ECG) increased 2.5 min after iohexol administration, and end-tidal carbon dioxide decreased to 12 mmHg. A progressive ST segment depression was observed on ECG. Subsequently, the ECG waveform changed to ventricular fibrillation. However, spontaneous circulation returned following cardiopulmonary resuscitation. Myocardial ischemia or anaphylactic shock was suspected in the dog, which explains the ST segment depression observed on ECG. When performing radiological examinations with a contrast agent, the ECG waveform changes, such as an increase in heart rate, R-wave amplitude, or ST segment depression, should be carefully monitored. This might enable early detection of cardiac dysfunction and the ensuing cardiac arrest in dogs.

Treatment of dogs with severe heartworm disease

Fortunately, the majority of dogs diagnosed with heartworm infection are asymptomatic (or have only mild symptoms such as intermittent cough) and go through adulticide therapy without complication. Complications occurring with heartworm infection and during its treatment most often directly reflect the pulmonary vascular and parenchymal injury inflicted by Dirofilaria immitis. Clinical signs may include exercise intolerance, frequent cough, hemoptysis, tachypnea, and dyspnea. Severe manifestations such as heart failure and caval syndrome may prove fatal. Acute hypersensitivity reactions after initiation of macrocyclic lactone preventive therapy in microfilaremic dogs or after melarsomine injection during adulticide therapy do occur, but are uncommon. This article reviews complications associated with heartworm infection.

Suspected Anaphylactic Reaction to Ketamine in 3 Yucatan Swine (Sus scrofa)

This case series describes the clinical courses of 3 juvenile Yucatan miniature swine (Sus scrofa) that experienced a suspected anaphylactic reaction to ketamine hydrochloride during premedication for protocol-related surgery. All 3 swine rapidly developed diffuse erythema shortly after injection with ketamine-containing drug combinations. Clinical signs ranged from tachycardia and erythema alone to tachycardia and erythema followed by respiratory and cardiac arrest. Ketamine was considered the most likely cause of these reactions because it was the only agent in the premedication sedation combination that was used in all 3 swine. Subsequent intradermal skin testing confirmed this suspicion. With supportive care measures and standard medical interventions for anaphylaxis, all 3 animals recovered well and went on to be successful experimental subjects when an alternative anesthetic regimen that did not contain ketamine was used. To our knowledge, this report is the first description of a suspected adverse ketamine reaction of this type in swine despite the widespread use of the drug in this species. Ketamine anaphylaxis is rare in people, but the few cases described presented with symptoms similar to the clinical signs seen in the pigs in this report. In addition to highlighting a potential adverse drug reaction to ketamine in swine, this case series demonstrates the value of emergency preparedness for even the most routine of procedures.

Feline asthma and heartworm disease: Clinical features, diagnostics and therapeutics

PRACTICAL RELEVANCE

For feline practitioners, the cat with a cough or respiratory distress and thoracic radiographs with a bronchial or bronchointerstitial pattern suggests lower airway disease. Two important differentials, allergic asthma and heartworm disease (HWD), have many overlapping clinicopathologic features, but also clear and important differences in terms of cause and disease progression, treatment and prognosis. Notably, asthma is readily treatable and HWD is preventable.

CLINICAL SIGNIFICANCE

Feline HWD comprises two clinical syndromes: the comparatively recently described heartworm-associated respiratory disease (HARD) and adult HWD. The former is much more common; very few cats with HARD develop adult HWD. In HARD, following death of immature worms, pulmonary lesions may improve over time ('self-cure'). Lesions of adult HWD also improve over time as long as reinfection does not occur; however, with death of adult heartworms, mortality is high, and the prognosis is guarded. In asthma, morbidity is relatively high, but mortality is low, with an overall good to excellent prognosis.

DISEASE RECOGNITION

Feline asthma is encountered worldwide. In the authors' impression, feline HWD is often under-recognized.

AIMS

The aim of this review is to assist clinicians in differentiating feline asthma from feline HWD; as such, the emphasis is on distinguishing clinical features, as well as on diagnostics, therapy and prognosis. In differentiating these conditions, clinicians can attempt the goal of properly managing these diseases and can best educate owners on prognosis.

EVIDENCE BASE

For both feline asthma and feline HWD, the authors have drawn on the available peer-reviewed literature studies involving experimental models as well as spontaneous disease.

Suspected anaphylactic shock associated with administration of tranexamic acid in a dog

A 10-year-old male castrated Maltese was referred with clinical signs of hematuria, stranguria, and pollakiuria. The dog was diagnosed with sterile hemorrhagic cystitis with urethroliths and cystoliths. To remove the uroliths, the dog underwent retrograde urohydropropulsion followed by a cystotomy. The following day, persistent bleeding in the urinary bladder was identified with large hematoma, hematuria and anemia. In order to reduce bleeding, the dog received 10 mg/kg of tranexamic acid (TXA) intravenously. Immediately after TXA administration, the dog developed anaphylactic shock manifested by hypotension, hypothermia, tachycardia and a dull mentation. Thus, an emergency treatment including bolus injection of crystalloid, administration of dexamethasone and diphenhydramine, and oxygen supplementation was given, after which the dog quickly recovered within a few minutes.

Review of oncological emergencies in small animal patients

Oncological emergencies can occur at any time during the course of a malignancy and need to be recognized promptly to maximize successful outcomes. Emergencies are characterized as chemotherapy-induced, paraneoplastic syndromes, or directly related to the neoplasm. Prompt identification with treatment of these emergencies can prolong survival and improve quality of life, even in the setting of terminal illness. This review aims to educate the reader on the pathophysiology, clinical presentation and treatment of some of these emergencies, and to review the current veterinary literature to help educate veterinarians in primary and tertiary facilities to know how to diagnose and treat these serious conditions.

EAACI position paper: Comparing insect hypersensitivity induced by bite, sting, inhalation or ingestion in human beings and animals

Adverse reactions to insects occur in both human and veterinary patients. Systematic comparison may lead to improved recommendations for prevention and treatment in all species. In this position paper, we summarize the current knowledge on insect allergy induced via stings, bites, inhalation or ingestion, and compare reactions in companion animals to those in people. With few exceptions, the situation in human insect allergy is better documented than in animals. We focus on a review of recent literature and give overviews of the epidemiology and clinical signs. We discuss allergen sources and allergenic molecules to the extent described, and aspects of diagnosis, prophylaxis, management and therapy.

Spontaneous hemoperitoneum and anaphylactic shock associated with Hymenoptera envenomation in a dog

OBJECTIVE

To describe the clinical presentation of a dog with spontaneous hemoperitoneum associated with anaphylactic shock from Hymenoptera envenomation.

CASE SUMMARY

An 8-year-old female neutered Beagle presented as an emergency for acute onset of collapse, hematemesis, and hematochezia. The dog was tachycardic, tachypneic, and hypotensive. Initial assessment revealed a hemoperitoneum with documentation of a nonclotting sanguineous peritoneal effusion with PCV 81% and total protein concentration 65 g/L (6.5 g/dL). No obvious masses were appreciated ultrasonographically during original presentation and cytology of the peritoneal effusion was unremarkable. Peripheral PCV was 67% and total plasma protein concentration was 72 g/L (7.2 g/dL). A bee stinger was located in the right upper lip after presentation and was postulated to be the inciting trigger for the abdominal hemorrhage and shock. The patient was medically stabilized and ultimately made an uneventful recovery. Abdominal ultrasound performed 3 days after discharge revealed a single 0.85 cm hyperechoic liver nodule. Follow-up evaluation at 6 and 18 months after presentation documented a normal physical examination, unremarkable thoracic radiographs, and no change in the original hyperechoic liver nodule.

NEW OR UNIQUE INFORMATION PROVIDED

This report details an unusual clinical presentation of anaphylactic shock due to Hymenoptera envenomation in a dog. To the authors' knowledge, spontaneous hemoperitoneum associated with anaphylaxis and bee envenomation has not been documented in the veterinary literature.

Seizure-like activity after gadolinium administration in an anaesthetised foal undergoing magnetic resonance imaging

The use of MRI has been recently increasing in veterinary patients, and this modality has been adapted for use in large animals with the concurrent use of gadolinium-based contrast media. Possible adverse reactions to its administration have been described in human and veterinary medicine, but there are no reports in foals. This case report describes the occurrence of seizure-like activity following administration of gadolinium to a 1.5-month old Finnish warmblood foal that was admitted for an MRI scan and cerebral spinal fluid collection. After the administration of contrast media, severe muscle twitching was observed. Prompt intervention, facilitated by constant patient monitoring and administration of propofol and diazepam, resulted in the control of the seizure and a favourable outcome. Since no alterations were found during the diagnostic investigation, it was suspected that the seizure-like activity might have been an adverse reaction to the contrast medium.

A serious adverse event secondary to rapid intravenous levetiracetam injection in a dog

OBJECTIVE

To describe a serious adverse event as a result of rapid intravenous injection of undiluted levetiracetam in a dog.

CASE SUMMARY

An 8-year-old female spayed Chihuahua was evaluated for cluster seizures and tachypnea. The patient was administered an intravenous dose of undiluted levetiracetam (60 mg/kg) and immediately developed tachycardia, hyperglycemia, hypotension, and a dull mentation. The patient's blood pressure and mentation did not respond to intravenous fluid boluses but improved immediately after administration of epinephrine intravenously. The patient subsequently developed respiratory failure necessitating mechanical ventilation, prior to cardiac arrest. Necropsy examination noted a pulmonary inflammatory cell infiltrate, pulmonary edema, and interstitial pneumonia.

NEW OR UNIQUE INFORMATION PROVIDED

This report documents a serious adverse event associated with intravenous levetiracetam administration to a dog.

Fluorescein sodium-guided resection of intracranial lesions in 22 dogs

OBJECTIVE

To evaluate the safety of an intraoperative fluorescein sodium (FS) injection and elucidate the relationships between the MRI findings, pathological diagnoses, and intraoperative staining characteristics of intracranial lesions in 22 dogs.

STUDY DESIGN

Prospective case series.

ANIMALS

Twenty-two dogs with intracranial lesions.

METHODS

FS was intravenously administered to 22 dogs undergoing craniotomy for suspected intracranial tumors to evaluate perioperative and postoperative adverse effects. The intensities and patterns of gadolinium (Gd) enhancement on preoperative magnetic resonance imaging and intraoperative FS staining were graded, and their relationship was evaluated. Intraoperative FS staining characteristics and pathological diagnoses were compared.

RESULTS

The only adverse effect noted was repetitive vomiting in 2 dogs. The intensities and patterns between preoperative Gd enhancement and intraoperative FS staining appeared to agree. High-grade glioma and histiocytic sarcoma had more intense FS staining. Lesions with strong Gd enhancement, including meningiomas and choroid plexus tumors, also had intense FS staining.

CONCLUSION

The intraoperative use of FS is a simple and safe technique to guide the resection of intracranial lesions in dogs. The findings on Gd enhancement, FS staining, and histopathology appeared to agree but require validation in a larger set of cases.

CLINICAL SIGNIFICANCE

The intraoperative use of FS may improve the prognosis of dogs with brain tumors by guiding the resection of lesions.

Australian elapid snake envenomation in cats: Clinical priorities and approach

Practical relevance: No fewer than 140 species of terrestrial snakes reside in Australia, 92 of which possess venom glands. With the exception of the brown tree snake, the venom-producing snakes belong to the family Elapidae. The venom of a number of elapid species is more toxic than that of the Indian cobra and eastern diamondback rattle snake, which has earned Australia its reputation for being home to the world's most venomous snakes. Clinical challenges: The diagnosis of elapid snake envenomation is not always easy. Identification of Australian snakes is not straightforward and there are no pathognomonic clinical signs. In cats, diagnosis of envenomation is confounded by the fact that, in most cases, there is a delay in seeking veterinary attention, probably because snake encounters are not usually witnessed by owners, and also because of the tendency of cats to hide and seek seclusion when unwell. Although the administration of antivenom is associated with improved outcomes, the snake venom detection kit and antivenom are expensive and so their use may be precluded if there are financial constraints. Evidence base: In providing comprehensive guidance on the diagnosis and treatment of Australian elapid snake envenomation in cats, the authors of this review draw on the published veterinary, medical and toxicology literature, as well as their professional experience as specialists in medicine, and emergency medicine and critical care.

Incidence of anaphylactic reactions after propofol administration in dogs

Propofol is an anesthetic agent suspended in an emulsion system that includes egg yolk lecithin and soybean oil, because of which, there is concern about the use of propofol in patients allergic to these substances. We examined the association between propofol administration and incidence of adverse events in dogs with allergy to egg yolk lecithin and soybean oil. On the basis of the findings of an allergen-specific immunoglobulin E (IgE) test, 14 dogs with high levels (high-IgE group) and 7 dogs with low levels (normal-IgE group) of IgE were selected. Following intravenous administration of propofol, the incidence of anaphylactic reactions and plasma histamine concentrations under general anesthesia maintained with isoflurane throughout surgery were compared between the two groups. The frequency of anaphylactic reactions and plasma histamine concentrations were compared by the chi-square test and Student t-test, respectively. The statistical significance for both tests was set at P<0.05. In the high- and normal-IgE groups, the average frequencies of anaphylactic reactions after propofol administration were 21.4 and 14.3%, and the mean plasma histamine concentrations were 167.9 ± 94.5 nM and 65.7 ± 40.3 nM, respectively. Animals of neither groups experienced shock-like symptoms. These results revealed that propofol might be relatively safe, although careful perioperative anesthesia monitoring and standby protocols are required when using propofol in dogs with a history of allergic diseases or high chicken- or soybean-specific IgE levels.

Pharmacokinetics of caspofungin acetate to guide optimal dosing in cats

Cats are the most common mammal to develop invasive fungal rhinosinusitis caused by cryptic species in Aspergillus section Fumigati that are resistant to azoles but susceptible to caspofungin. In this study nonlinear mixed-effects pharmacokinetic modeling and simulation was used to investigate caspofungin pharmacokinetics and explore dosing regimens in cats using caspofungin minimum effective concentrations (MECs). Plasma concentrations in healthy cats were determined using HPLC-MS/MS after administration of a single and seven consecutive daily intravenous doses of 1 mg/kg caspofungin. In the final pharmacokinetic model an optimum maximum concentration (C_max): MEC ratio of 10–20 was used to guide caspofungin efficacy. Simulations were performed for dosing regimens (doses 0.25–2 mg/kg and 6–72 h dosing intervals) with and without inclusion of a loading dose. Using a 1 mg/kg dose C_max first dose was 14.8 μg/mL, C_max at steady state was 19.8 μg/mL, C_min was 5 μg/mL and C_max: MEC was >20 in 42.6% of cats after multiple doses. An optimal C_max: MEC ratio was achieved in caspofungin simulations using 0.75 mg/kg q 24 h or 1 mg/kg q 72h. However, at 1 mg/kg q 72h, C_min was < MEC (<1 μg/mL) in over 95% of the population. Using a loading dose of 1 mg/kg and a daily dose of 0.75 mg/kg thereafter, the Cmax: MEC was optimal and C_min was > 2.5 μg/mL for 98% of the population. Based on the modeling data this dosing regimen is likely to achieve target therapeutic concentrations, meet the proposed C_max: MEC window and provide consistent exposure between doses.