Comparison of Thames Medical CAT+ Doppler and SunTech Vet 20 oscillometric devices for non-invasive blood pressure measurement in conscious cats.

OBJECTIVES: A comparative assessment of systolic blood pressure (BP) measurement agreement and precision in two commonly used non-invasive BP devices was carried out in conscious cats. METHODS: Systolic BP measurements were obtained from 50 conscious cats as part of their clinical investigations. All measurements were taken by the same operator and were performed according to the American College of Veterinary Internal Medicine (ACVIM) consensus guidelines. The same cuff location and cuff size were used for paired measurements. The order of device use was randomised, and an arousal score was assigned during each procedure. Precision was assessed using standard deviation and coefficient of variance comparisons. Agreement was assessed using graphical and statistical comparisons of derived 'delta mean' and 'mean of means' data. RESULTS: A total of 50 cats aged between 3 months and 15 years were enrolled (29 domestic shorthair, seven domestic longhair, three British Shorthair, two Ragdoll, two Sphynx, two Persian, one Siamese, one Burmese, one Russian Blue, one Maine Coon and one Oriental) with a body weight in the range of 1.2-6.2 kg. BP measurements were in the range of 95-179 mmHg. Oscillometric measurements were associated with lower arousal scores. The Doppler device demonstrated superior repeatability precision. Body weight, sex, cuff size, cuff location, arousal score and the order in which the devices were used had no significant effect on precision or agreement. Correlation between the two devices was 0.0837 and agreement was considered clinically acceptable (<10 mmHg) in 32/50 (64%) cats. Of the 18 cats with suboptimal agreement, the oscillometric mean BP was higher in 14 (78%) cats. CONCLUSIONS AND RELEVANCE: Based on this study sample, suboptimal agreement between paired CAT+ Doppler and SunTech Vet20 oscillometric BP measurements in 36% of conscious cats suggests that these devices should not be used interchangeably. Compared with Doppler, oscillometric measurements were consistently higher, particularly at higher blood pressures. Further studies are required to assess which device has superior accuracy in conscious cats.

Distal esophageal sphincter achalasia in a Labrador retriever dog with polypoid gastric mucosal hyperplasia and pyloric stenosis.

An 11-year-old, neutered female, Labrador retriever dog was presented with a history of intractable vomiting, regurgitation, and coughing. Computed tomography (CT) imaging identified marked hypertrophy of the distal esophagus with a suspicion of distal esophageal achalasia, based on the observation of a "bird beak" appearance. This was later confirmed on a fluoroscopic swallow study. Marked hypertrophy of the gastric pylorus was also identified on CT imaging, and polypoid gastric mucosal hyperplasia was diagnosed based on the gross endoscopic appearance combined with gastric histopathology. Secondary aspiration pneumonia was diagnosed based on the results of CT imaging, bronchoscopy and bronchoalveolar lavage fluid analysis. Medical therapy alone failed to elicit any significant improvement, but clinical resolution was achieved following surgical intervention comprising Ventral Heller myotomy, Dor's fundoplication, and pyloroplasty.

Achalasie du sphincter oesophagien distal chez un chien de race Labrador avec hyperplasie polypoïde de la muqueuse gastrique et sténose du pylore. Une femelle Labrador stérilisée âgée de 11 ans fut présentée avec une histoire de vomissements intraitables, de régurgitation et de toux. Un examen par tomodensitométrie (CT) identifia une hypertrophie marquée de l'oesophage distal avec un doute d'achalasie oesophagienne distale, sur la base de l'observation d'une apparence en « bec d'oiseau ¼. Ceci fut ultérieurement confirmé par examen fluoroscopique. Une hypertrophie marquée du pylore gastrique fut également identifiée lors de l'examen par CT, et une hyperplasie polypoïde de la muqueuse gastrique fut diagnostiquée sur la base de l'apparence macroscopique lors de l'endoscopie combinée avec l'examen histopathologique de la muqueuse gastrique. Une pneumonie par aspiration secondaire fut diagnostiquée basée sur les résultats du CT, de la bronchoscopie et de l'analyse du liquide de lavage broncho-alvéolaire. Une thérapie médicale seule ne parvint pas à éliciter une amélioration significative, mais une résolution clinique fut obtenue à la suite d'une intervention chirurgicale comprenant une myotomie ventrale de Heller, une fundoplicature de Dor, et une pyloroplastie.(Traduit par Dr Serge Messier).

Suspected choledochal cyst in a domestic shorthair cat.

A 9-year-old female neutered domestic shorthair cat was presented with a history of polyphagia, weight loss and inappropriate urination. Clinical examination revealed jaundice and a mid-cranial abdominal mass. Further investigations revealed a large extra-hepatic cyst originating from the biliary tract (choledochal cyst). Concurrent chronic, active neutrophilic cholangitis and chronic lymphoplasmacytic pancreatitis were also noted. Surgical drainage, subtotal resection and omentalisation of the cyst, along with supportive medical management, were successful in relieving the clinical signs.

Alternaria species infection in nine domestic cats.

A case series of nine domestic cats with culture-confirmed Alternaria species infection is presented, with conclusions drawn regarding signalment, clinical signs, treatment and outcome. Middle aged neutered males were over-represented and all presented with cutaneous lesions involving the extremities (nose, pinnae and digits). Lesions were mainly slow-growing, poorly circumscribed nodules or plaques but some also presented as non-healing wounds. A combination of surgical excision with adjunctive medical therapy appeared to be the most successful treatment option but long courses of medical therapy were generally required and recurrence was common.

Evaluation of real-time RT-PCR for the quantification of FCoV shedding in the faeces of domestic cats.

Faecal samples were taken from cats living in multi-cat households with endemic feline coronavirus (FCoV) infection. Total RNA was extracted from faecal suspensions and FCoV RNA was quantified using a real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay. The real-time RT-PCR threshold cycle (C(T)) values were consistently high suggesting that the samples contained very little viral RNA. However, experiments in which RNA extracted from FCoV-infected cell culture supernatants was combined with RNA extracted from faecal suspensions revealed the presence of faecal factors that significantly inhibited the reverse transcription reaction. Consequently, three methods of RNA extraction were investigated and RNA dilution was undertaken to investigate whether the effects of the faecal inhibitors could be reduced. Our results show that using the QIAgen RNA mini kit for RNA extraction and dilution of the RNA samples helps to reduce the inhibitory effects. However, because the extent of the inhibitory effects varied between faecal samples, accurate quantification proved difficult. We, therefore, conclude that although real-time RT-PCR provides an excellent method for detecting the presence of viral shedding, quantification of FCoV RNA in faecal material has to take into account the possible effects of RT-PCR inhibitors. It is, therefore, essential that all new assays, and the methods of sample preparation, are carefully evaluated before being used in a clinical setting.

Type I feline coronavirus spike glycoprotein fails to recognize aminopeptidase N as a functional receptor on feline cell lines.

There are two types of feline coronaviruses that can be distinguished by serology and sequence analysis. Type I viruses, which are prevalent in the field but are difficult to isolate and propagate in cell culture, and type II viruses, which are less prevalent but replicate well in cell culture. An important determinant of coronavirus infection, in vivo and in cell culture, is the interaction of the virus surface glycoprotein with a cellular receptor. It is generally accepted that feline aminopeptidase N can act as a receptor for the attachment and entry of type II strains, and it has been proposed that the same molecule acts as a receptor for type I viruses. However, the experimental data are inconclusive. The aim of the studies reported here was to provide evidence for or against the involvement of feline aminopeptidase N as a receptor for type I feline coronaviruses. Our approach was to produce retroviral pseudotypes that bear the type I or type II feline coronavirus surface glycoprotein and to screen a range of feline cell lines for the expression of a functional receptor for attachment and entry. Our results show that type I feline coronavirus surface glycoprotein fails to recognize feline aminopeptidase N as a functional receptor on three continuous feline cell lines. This suggests that feline aminopeptidase N is not a receptor for type I feline coronaviruses. Our results also indicate that it should be possible to use retroviral pseudotypes to identify and characterize the cellular receptor for type I feline coronaviruses.

Genomic RNA sequence of feline coronavirus strain FCoV C1Je.

This paper reports the first genomic RNA sequence of a field strain feline coronavirus (FCoV). Viral RNA was isolated at post mortem from the jejunum and liver of a cat with feline infectious peritonitis (FIP). A consensus sequence of the jejunum-derived genomic RNA (FCoV C1Je) was determined from overlapping cDNA fragments produced by reverse transcriptase polymerase chain reaction (RT-PCR) amplification. RT-PCR products were sequenced by a reiterative sequencing strategy and the genomic RNA termini were determined using a rapid amplification of cDNA ends PCR strategy. The FCoV C1Je genome was found to be 29,255 nucleotides in length, excluding the poly(A) tail. Comparison of the FCoV C1Je genomic RNA sequence with that of the laboratory strain FCoV FIP virus (FIPV) 79-1146 showed that both viruses have a similar genome organisation and predictions made for the open reading frames and cis-acting elements of the FIPV 79-1146 genome hold true for FCoV C1Je. In addition, the sequence of the 3'-proximal third of the liver derived genomic RNA (FCoV C1Li), which encompasses the structural and accessory protein genes of the virus, was also determined. Comparisons of the enteric (jejunum) and non-enteric (liver) derived viral RNA sequences revealed 100% nucleotide identity, a finding that questions the well accepted 'internal mutation theory' of FIPV pathogenicity.

Genomic RNA sequence of Feline coronavirus strain FIPV WSU-79/1146.

A consensus sequence of the Feline coronavirus (FCoV) (strain FIPV WSU-79/1146) genome was determined from overlapping cDNA fragments produced by RT-PCR amplification of viral RNA. The genome was found to be 29 125 nt in length, excluding the poly(A) tail. Analysis of the sequence identified conserved open reading frames and revealed an overall genome organization similar to that of other coronaviruses. The genomic RNA was analysed for putative cis-acting elements and the pattern of subgenomic mRNA synthesis was analysed by Northern blotting. Comparative sequence analysis of the predicted FCoV proteins identified 16 replicase proteins (nsp1-nsp16) and four structural proteins (spike, membrane, envelope and nucleocapsid). Two mRNAs encoding putative accessory proteins were also detected. Phylogenetic analyses confirmed that FIPV WSU-79/1146 belongs to the coronavirus subgroup G1-1. These results confirm and extend previous findings from partial sequence analysis of FCoV genomes.

Oesophageal strictures in cats associated with doxycycline therapy.

Four cases of oesophageal stricture subsequent to doxycycline administration are reported. All cases were young to middle age (median age 3 years; range 1-7 years), and either domestic shorthair or domestic longhair breed. In all cases the predominant clinical sign was regurgitation, which developed at variable times after doxycycline administration. In all cases the reason for doxycycline use was treatment or prophylaxis of suspected infections (Mycoplasma haemofelis, Chlamydophila felis or Bordetella bronchiseptica), and the duration of therapy was variable. In one case the stricture was definitively diagnosed at post mortem examination, in the three other cases, definitive diagnosis was by endoscopy. Balloon dilation was successful in the three cases that were treated. This is the largest case series, to date, of oesophageal disease in cats associated with doxycycline administration. Caution should be exercised when administering oral medication to cats, especially doxycycline, and should be accompanied either by a water or food swallow.