Dominic Barfield

Feline Blood Transfusions A Pinker Shade of Pale

Practical relevance Blood transfusions are a potentially life-saving procedure that are within the reach of most small animal practitioners. Only minimal equipment is required. Patient group Any cat with clinical signs attributable to a reduced red blood cell mass that is affecting oxygen transport (as a result of reduced packed cell volume or acute blood loss) is a potential candidate for a transfusion. Clinical challenges Although the principles of transfusion medicine are not complicated, there can be fatal consequences if certain steps are omitted. Diagnostics Blood typing kits and blood filters are readily available from veterinary wholesalers, laboratories and blood banking services. Evidence base Over the past three decades, a substantial body of clinical research and reports has built up covering feline blood types and transfusion medicine. This article draws on that research to provide clinical guidance aimed at all veterinarians in feline or small animal practice who either currently practise transfusion medicine or plan to do so.

Synovial Osteochondroma Involving the Elbow of a Cat

Clinical presentation A 12-year-old spayed domestic crossbred cat presented because she would not walk down stairs. A firm swelling on the medial aspect of the elbow was detected during physical examination. The lesion was not hot or painful on palpation and the lameness was mild, but the elbow had a reduced range of motion compared with the contralateral limb. Diagnosis and treatment Plain radiographs, physical findings, the appearance of the lesion at surgery and histopathological examination of biopsy specimens suggested the mass was a synovial osteochondroma arising from synovial membrane near the medial portion of the elbow joint. Resection of the lesion improved the cats mobility and overall clinical status. At the time of writing, the cat continued to do well 18 months following surgery and was receiving standard doses of meloxicam for the concurrent elbow osteoarthritis. Practical relevance Practitioners should be alert to the possibility of this benign entity. Misdiagnosis as a chondrosarcoma, for example, might conceivably lead to radical and unnecessary amputation.

Pupillary dilation, tachycardia and abnormal behaviour in a young cat

An 8-month-old spayed Himalayan cat was presented on a Monday morning by one of the cat’s owners with an acute history of ‘agitation’ and being unable to walk. The cat lived exclusively indoors in an affluent suburb near the central business district of Sydney. It had a habit of sleeping in the kitchen cupboard, and had been accidentally locked in that cupboard overnight. On inspection, the patient was unsettled, but able to walk. It reacted inappropriately and excessively to innocuous stimuli, such as the approach of a friendly person. Physical findings included pronounced pupillary dilation (Fig 1) and tachycardia (heart rate> 240 beats per minute (bpm)). Rectal temperature was not taken because of the anxious state of the cat. The cardiac impulse was accentuated, the heart sounds

Feline non-regenerative immune-mediated anaemia: features and outcome in 15 cases

Objectives Pure red cell aplasia (PRCA) and non-regenerative immune-mediated haemolytic anaemia (NRIMHA) are uncommon causes of non-regenerative anaemia affecting the bone marrow in the cat. This retrospective study aimed to describe the clinical features, treatment and outcome (remission and survival) of cats with these disorders. Methods Cases of PRCA and NRIMHA presenting between 2009 and 2013 were retrieved. Clinical features including signalment, history, clinical signs and diagnostic investigations were recorded, as well as treatment(s) used and outcome (remission and survival). Outcome was compared for PRCA and NRIMHA. Results Fifteen cats met inclusion criteria: seven with PRCA and eight with NRIMHA. The majority (12/15) were younger than 3 years of age. Volume overload was common (8/11). Treatment with whole blood transfusions with or without Oxyglobin was necessary in most cats (14/15) and resulted in congestive heart failure in one cat. Most cats (11/15) achieved remission 12–42 days after starting immunosuppressive treatment. Treatment protocols associated with remission were glucocorticoids alone (remission in 6/7 cats), glucocorticoids and chlorambucil (remission in 3/6 treated cats), glucocorticoids and ciclosporin (one cat only) and ciclosporin alone (one cat only). Relapse was observed in 3/11 cats, and 8/11 cats were still receiving treatment at the time of follow-up. Outcome (remission and survival) did not differ between PRCA and NRIMHA. Conclusions and relevance PRCA and NRIMHA are uncommon causes of anaemia in predominantly young cats. The prognosis is reasonable, with a mortality rate of 27%, and it can take at least 6 weeks before remission is observed. Following clinical remission, gradual withdrawal of immunosuppressive treatments should be attempted, with close monitoring for relapse; some cats may require long-term treatment. This study is the first to report the use of chlorambucil as an adjunctive immunosuppressant in these cases. Outcome did not differ for PRCA and NRIMHA.

Benzalkonium chloride intoxication in cats

THE UK is fortunate to have a Veterinary Poisons Information Service (VPIS). A paper summarised on p 229 of this issue of Veterinary Record by Bates and Edwards (2014) concerning benzalkonium chloride (BAC) exposure in cats is testament to the excellent database analyses VPIS conducts as part of its mission. It is pertinent that during the period studied, only one case of feline BAC intoxication was reported in the adverse drug reaction database of the Center for Veterinary Medicines in the USA, with another single case recorded by the Australian Pesticides and Veterinary Medicines Authority, while the VPIS recorded 245 cases. Although the paper is retrospective, the data is sufficiently robust to paint an evidence-based clinical picture for both owners and the veterinary team confronted with the management of such patients. The number of cases Bates and Edwards reviewed is huge, reflecting the commonness and importance of this toxicosis, and the excellent record-keeping of this group. The first question that springs from the paper is ‘Why cats?’ (or, ‘Why not dogs?’). The answer is straightforward, at least in part. The intoxication reflects the behavioural predisposition of cats to groom any abnormal material from their coat or pads. This often gets them into trouble when they share the environment with people who use different chemical agents to clean surfaces on which cats may walk or roll. It is the same reason why cats are at risk of lead intoxication from flaky paint (they groom it off their coat and ingest it) (Knight and Kumar 2003), why flea allergens in the coat can trigger severe secondary eosinophilic granuloma lesions on the lingual surface (Malik 2007), and why cats come to ingest illicit substances that mysteriously find their way onto their coat or paws (Barfield and others …

Systemic Scedosporium prolificans infection in an 11‐month‐old Border collie with cobalamin deficiency secondary to selective cobalamin malabsorption (canine Imerslund‐Gräsbeck syndrome)

An 11-month-old Border collie presented collapsed and continued to deteriorate rapidly despite supportive treatment. The dog had a history of failure to thrive and recurring respiratory infection. Laboratory abnormalities included neutrophilic leucocytosis, Heinz body anaemia, hyperammonaemia, hyperbilirubinaemia, proteinuria and hypocobalaminaemia. Post-mortem examination revealed multi-focal necrosis within the heart, kidneys, pancreas, liver, meninges and cerebral cortex. Fungal hyphae in lesions were identified as Scedosporium prolificans following culture. Subsequent genotyping confirmed that the dog carried the CUBN:c.8392delC mutation in a homozygous state, verifying hereditary cobalamin deficiency (a.k.a. Imerslund-Gräsbeck syndrome). Cobalamin deficiency may have been a predisposing factor for the development of systemic fungal infection in this dog.

Clinical findings and results of diagnostic imaging in 82 dogs with gastrointestinal ulceration

OBJECTIVES To describe clinical and imaging findings in dogs with confirmed gastrointestinal ulceration, to compare findings in dogs with perforated and non-perforated ulcers and to estimate the sensitivities of radiography, ultrasonography and computed tomography (CT) for gastrointestinal ulceration and perforation. METHODS Retrospective review of medical records of 82 dogs that had a macroscopic ulcer in the gastric or intestinal mucosa diagnosed directly at endoscopy, surgery or necropsy and had survey radiography, ultrasonography or a CT scan of the abdomen during the same period of hospitalisation. RESULTS The most frequent clinical signs were vomiting in 88% dogs, haematemesis in 32%, melaena in 31% and weight loss in 7%. The most frequent imaging findings in dogs with non-perforated ulcers were gastrointestinal mural lesion in 56%, mucosal defect compatible with an ulcer in 44% and peritoneal fluid in 21%. In dogs with perforated ulcers the most frequent imaging findings were peritoneal fluid in 83%, gastrointestinal mural lesion in 48%, peritoneal gas in 31% and mucosal defect compatible with an ulcer in 29%. Sensitivities of radiography, ultrasonography and CT were 30, 65 and 67% in dogs with non-perforated ulcers and 79, 86 and 93% in dogs with perforated ulcers, respectively. CLINICAL SIGNIFICANCE In dogs with non-perforated ulcers, survey radiography was usually negative whereas ultrasonography and CT frequently enabled detection of the site of the ulcer; in dogs with perforated ulcers, radiography was frequently positive for peritoneal gas and CT was a sensitive modality for both the ulcer and signs of perforation.

Retrospective evaluation of recurrent secondary septic peritonitis in dogs (2000–2011): 41 cases

OBJECTIVE To describe the clinical characteristics of recurrent septic peritonitis in dogs. DESIGN Multicenter retrospective observational study. ANIMALS Client-owned dogs with recurrent septic peritonitis. SETTING Three university emergency and referral hospitals. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Medical records from 3 veterinary university teaching hospitals were reviewed and data were collected using a standardized data collection sheet for all cases of septic peritonitis during the study period (2000-2011). Forty one dogs met the inclusion criteria for recurrent peritonitis. All dogs underwent relaparotomy. The original cause of septic peritonitis in these cases included previous surgery for gastrointestinal foreign body removal (n = 26), gastrointestinal neoplasia (n = 3), gastric or duodenal ulceration (n = 3), biliary tract leakage (n = 2), and single instance for each of the following: penetrating foreign body, hernia strangulation, intussusception, mesenteric volvulus, infection of the laparotomy incision, prostatic abscess, and trauma. Eighteen animals survived to discharge. There was no difference detected between survivors and nonsurvivors with recurrent peritonitis in terms of inciting cause, serum albumin concentration, surgical management, or provision of appropriate initial antimicrobials. The survival rate for dogs having recurrent peritonitis was 43.9% (18/41 dogs). CONCLUSIONS This retrospective study did not identify any significant prognostic indicators for dogs with recurrent peritonitis and that the mortality rate for dogs having more than one surgery for septic peritonitis is similar to that reported for a single surgery for septic peritonitis.

Assessment of feline blood for transfusion

IN a paper summarised on p 352 of this issue, Juvet and others (2011) describe the blood types of 176 cats in and around the Dublin area of Ireland as well as the prevalence of feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). The blood types of cats is a subject that has attracted significant study since Holmes first described two types in the Manchester area of the UK in the 1950s (Holmes 1950). The information gleaned from these studies is of great importance to the veterinary practitioner. The importance of blood typing feline patients for AB blood grouping before transfusion cannot be stressed enough due to the risk of fatal transfusion reactions that can occur in type B cats due to the presence of preformed anti-A antibodies. Previous studies have identified not only geographical variation, but also breed variation and have demonstrated a lack of predictability of feline blood types. Interestingly, recent studies have also identified an increased incidence of type B cats compared with older studies. Geographically, it is thought that the basis of different blood types in the AB group system is most likely to be related to the blood type of cats introduced to a certain area as a result of ‘the founder effect’. This is clearly demonstrated with the introduction of certain breeds from a single blood type to different regions, for example, Siamese and Bengal cats in the UK (Gunn-Moore and others 2009). This is possibly the …

Use of calcium folinate in the management of accidental methotrexate ingestion in two dogs

CASE DESCRIPTION 2 English Pointers were suspected of having consumed toxic doses of methotrexate, a dihydrofolate reductase inhibitor frequently used in human and veterinary chemotherapeutic protocols. CLINICAL FINDINGS Potentially toxic plasma concentrations of methotrexate were detected in both dogs. Results of physical examination, a CBC, blood gas analysis, and serum biochemical analysis were predominantly unremarkable, although 1 dog had mild hyponatremia (1372 mmol/L; reference range, 140 to 153 mmol/L) and mild hypocalcemia (1.03 mmol of ionized calcium/L; reference range, 1.13 to 1.33 mmol of ionized calcium/L). TREATMENT AND OUTCOME Point-of-care determination of plasma methotrexate concentrations was not available; thus, palliative care was provided. Emesis was induced in both dogs by SC administration of apomorphine, and 3 doses of a suspension of activated charcoal with sorbitol were administered orally over a 6-hour period. Fluid diuresis was initiated in both dogs by administration of a compound sodium lactate solution, and N-acetylcysteine was administered IV to both dogs as a hepatoprotectant. A solution of calcium folinate (also known as leucovorin) was administered IV to both dogs to mitigate the effects of ingested methotrexate. No adverse effects associated with calcium folinate administration were identified, and no clinical or pathological evidence of methotrexate intoxication was detected. CLINICAL RELEVANCE IV administration of calcium folinate appeared to prevent the pathological sequelae of methotrexate intoxication without adverse effects. Administration of calcium folinate is recommended for the treatment of dogs with suspected or confirmed methotrexate overdose.