Bartonellosis in cats: a role in uveitis?

Demography and clinical pattern of newly diagnosed uveitis patients in Malaysia

Introduction

Uveitis is one of the common causes of visual impairment in Malaysia. It remains a challenging entity to diagnose and manage due to variation in its clinical presentation. This study aims to observe the demographic and clinical pattern of cases from the participating ophthalmology units in Malaysia.

Methods

This study involved prospective and multicentered data collection for patients newly diagnosed with uveitis from 1^st January 2018 to 31^st December 2018. Variables collected and analyzed included age, gender, ethnicity, nationality, state of origin, laterality, granulomatous or non-granulomatous uveitis, and etiology of uveitis.

Results

A total of 1199 newly diagnosed uveitis patients were analyzed within the study period. There was a significant association between the anatomical location of uveitis with age at presentation. The percentage of patients with anterior uveitis was higher in the ‘40 to 60’ years and ‘above 60’ years age groups at 52.1% (n = 210) and 61.3% (n = 114) respectively. In contrast the percentage of patients with posterior and panuveitis was higher in the 1 to 20 and 20 to 40 years age groups at 51.4% (n = 54) and 48.7% (n = 246) respectively.

Sixty three percent of the patients presented with unilateral uveitis (n = 760, p < 0.001) vs bilateral. Non-granulomatous uveitis comprised 84.5% of all patients (n = 1013, p < 0.001) compared to granulomatous uveitis. Non-infectious etiology contributed to 65.7% of all patients (n = 788, p < 0.001) with the majority being unclassifiable uveitis (n = 686, 57.2%,). Specific inflammatory entities contributed to only 8.5% (n = 102) of the non-infectious causes with Vogt-Koyanagi-Harada (VKH) syndrome being the most common (n = 25, 2.1%,). Infectious uveitis comprised 34.3% (n = 411) with tubercular (TB) uveitis (n = 105, 8.8%) and viral uveitis (n = 107, 8.9%) contributing the most followed by ocular Toxoplasmosis (n = 93,7.8%).]

Conclusion

This study has highlighted the demographic data and common causes of uveitis in Malaysia.

A multicenter retrospective study into endogenous causes of uveitis in cats in the United Kingdom: Ninety two cases

PURPOSE

The purpose of this study was to investigate the most common causes of endogenous feline uveitis in a UK referral population and to investigate associations based on signalment.

METHODS

Retrospective multicenter cross-sectional study from 2010 to 2019 including cats presented to the Animal Health Trust and the Royal Veterinary College with clinical signs consistent with uveitis. Cats were included in analyzes if they had a full physical examination including an ophthalmic examination, complete blood count, serum biochemistry, and infectious disease testing for at least two diseases unless the diagnosis was found on clinical examination (eg, neoplasia).

RESULTS

A total of 92 cats were included in the study. The majority of cats presenting with uveitis were male (66.3%). The most common causes of endogenous uveitis were idiopathic uveitis (42/92 45.7%), feline infectious peritonitis (FIP) 15/92 16.3%), and lymphoma (10/92 10.9%). Fisher's exact test showed differences in breed across diagnosis groups (p = .002) with purebred cats being overrepresented in the lymphoma and FIP groups. Kruskal-Wallis test showed differences in median age across diagnosis groups (p < .001) with cats in the FIP group having the youngest age (median 1.4 years, interquartile range (IQR) 0.4-1.8 years) and cats in the neoplasia (primary or paraneoplastic) group having the oldest age (median 12.8 IQR 10.8-13.8). Idiopathic uveitis was unilateral in 56.1% of cases, and infectious causes were unilateral in 47.8% of cases.

CONCLUSIONS

The most common cause of endogenous uveitis in a population of cats in the UK was idiopathic uveitis, followed by FIP and lymphoma.

Hereditary cataract in the Bengal cat in Poland

BACKGROUND

This paper reports the significant prevalence of a presumed hereditary cataract in the Bengal cat breed in Poland. The nuclear part of the lens is affected and previous reports from Sweden and France for this type of feline cataract suggest that a recessive mode of inheritance is probably involved.

RESULTS

Presumed congenital or neonatal cataract involving the posterior nuclear part of each lens was initially diagnosed in a 12 month old male Bengal cat. As both parents and a sibling were also affected with cataract, a group of 18 related and 11 non-related cats was then subsequently examined. Eight related cats and one non-related cat were found to be similarly affected. A breed survey was then completed using an additional five centres across Poland and a further 190 related cats were examined. A total of 223 cats have been involved in this study, with 75 (33%) being affected with several types of cataract and 67 (30%) being specifically affected with the same or similar nuclear lesions. Eight cats (3.6%) presented with other cataract types and a prominence of the posterior lens suture lines was recorded in 65 cats unaffected with cataract (29%). There were no demonstrable vision problems. Neither age nor coat colour was significantly associated with the nuclear cataract, but the nuclear cataract group had a higher proportion of females than the unaffected group. Pedigree analysis has indicated probable inheritance as a recessive trait.

CONCLUSIONS

These findings suggest that a presumably inherited nuclear cataract is present in the Bengal cat breed in Poland. It is considered to be either congenital or of very early onset, probably being inherited as a recessive trait. Although the lesion has no noticeable effect on vision, breeders in Poland and worldwide should be aware of the disease and clinical examination of young breeding stock prior to reproduction is advisable.

Causes of Feline Uveitis: A Retrospective Study of 96 Cases at the Faculty of Veterinary Medicine Bucharest, 2012-2015

Uveitis is a common cause of blindness in feline patients as incorrectly treated or its chronicization can lead to formation of pre-iridal fibrovascular membranes, pupillary block and secondary glaucoma. The objective of this study was to investigate the causes of uveitis in cats diagnosed at the Faculty of Veterinary Medicine, Bucharest between 2012 and 2015. Medical records were reviewed and cats were considered if complete diagnostic work-up, clinical examination and imaging studies were performed. All the feline cases were serologically tested for at least two of the common infectious causes: feline leukemia virus, feline immunodeficiency virus, feline coronavirus, Toxoplasma gondii, and Bartonella spp. Ninety-six cats with a mean age of 5.42 years, ranging from 1 month to 17 years old, with a male to female ratio of 1.33/1 were diagnosed with uveitis. The European domestic cat was overrepresented at 76% followed by Birman cat (6.3%), Persian cat (4.2%), Russian blue (4.2%), Norwegian cat (2%), British Short Hair (1%), Sphynx (1%) and Cornish Rex (1%). Infectious diseases were the cause of uveitis in 31 cases (32.3%), neoplasia was diagnosed in 22 cases (22.9%), uveitis secondary to septic keratitis in 8 cases (8.3%) and uveitis secondary to direct ocular trauma in 6 cases (6.3%). Twenty-nine cats (30.2%) with a mean age of 4.33 years old were diagnosed with idiopathic or immune-mediated uveitis, less than previously reported. Aqueous flare occurred in 91 cats and keratic precipitates were noted in 39 cats. The most common infectious cause of uveitis in this study was Toxoplasma gondii (n=18). Infectious diseases remain the most common cause of feline uveitis, therefore systemic evaluation and serological investigations should be performed in all cats with uveitis, cataract and glaucoma.

Metagenomic survey for viruses in Western Arctic caribou, Alaska, through iterative assembly of taxonomic units

Pathogen surveillance in animals does not provide a sufficient level of vigilance because it is generally confined to surveillance of pathogens with known economic impact in domestic animals and practically nonexistent in wildlife species. As most (re-)emerging viral infections originate from animal sources, it is important to obtain insight into viral pathogens present in the wildlife reservoir from a public health perspective. When monitoring living, free-ranging wildlife for viruses, sample collection can be challenging and availability of nucleic acids isolated from samples is often limited. The development of viral metagenomics platforms allows a more comprehensive inventory of viruses present in wildlife. We report a metagenomic viral survey of the Western Arctic herd of barren ground caribou (Rangifer tarandus granti) in Alaska, USA. The presence of mammalian viruses in eye and nose swabs of 39 free-ranging caribou was investigated by random amplification combined with a metagenomic analysis approach that applied exhaustive iterative assembly of sequencing results to define taxonomic units of each metagenome. Through homology search methods we identified the presence of several mammalian viruses, including different papillomaviruses, a novel parvovirus, polyomavirus, and a virus that potentially represents a member of a novel genus in the family Coronaviridae.