The effect of patient symptom awareness on the visual outcome in retinal detachment.

PURPOSE: To explore whether a patient's prior knowledge of the symptoms associated with rhegmatogenous retinal detachment (RRD) relates to the visual outcome after treatment. METHODS: We performed a prospective survey study on 126 patients receiving treatment for primary RRD between March and July 2021. RESULTS: Thirty-seven per cent (n = 47) of patients responded that they were aware of the RRD symptoms prior to the detachment. A history of RRD in the fellow eye or knowledge of family members treated for RRD was frequently reported as a reason for the patient's awareness of RRD symptoms. Patients aware of RRD symptoms presented significantly more often with an attached macula (χ2 , p = 0.002) and a better visual outcome following surgery (Mann-Whitney U, p = 0.028) compared to patients who were not aware of RRD-related symptoms. Among 76 patients with a myopic refractive error, only 15% (n = 11) indicated that they had been warned about the increased RRD risk related to myopia, suggesting that three-quarters of patients were not actively informed by their eye care professionals. CONCLUSION: RRD symptom awareness is significantly related to a higher rate of macula-on RRDs and better visual outcomes after treatment. There is limited awareness of increased RRD risk in myopic RRD patients. These findings suggest that counselling individuals at high risk of RRD about related symptoms is inadequate and better counselling may improve visual outcomes following RRD treatment.

Quantification of the health-status of the Dutch Labrador retriever population.

Health issues in purebred dogs are currently considered one of the biggest problems in companion animal health. The Labrador retriever (LR) is one of the most popular dog breeds. The aim of this study was to quantify LR breed health in comparison with mixed-breed dogs (MB), by using four different data sources: a veterinary practice management system (appr. 35,000 unique individuals LR + MB), data from two animal insurance companies (appr. 15,500 and 4500 individuals respectively), and a histopathological laboratory (appr. 4000 individuals). After extensive recoding of the data, health parameters utilised to quantify breed health were longevity, frequency of practice visits and insurance expense claims, and diagnostic codes. A Kaplan-Meier univariate and multivariable Cox proportional hazard model were used to evaluate longevity. A negative binomial model was used to analyse the frequency of visits, claims, and diagnostic codes in both sets of insurance data. Logistic regression was used to look into the categorical diagnostic codes in the laboratory data. The median lifespan of the LR was similar (12 years, practice data) or longer (10 versus 8 years, insurance data) than MB for individuals with a known birth and death date. When including censored individuals, survival time in the LR was comparable to MB individuals up to 10 years of age. Above 10 years of age, the LR lived a similar length as MB with a medium to large body size, but shorter than all MB. The LR visited the veterinary practice more often (risk ratio (RR) 1.2, 95% confidence interval 1.2-1.3), and also showed a higher frequency of insurance expense claims (RR 2.2 (2.1-2.3) and RR 1.2 (1.1-1.3) respectively for the two insurance data sets). The largest difference in organ systems between the LR and MB in insurance claims was related to ears (RR 5.3 (4.8-5.8) and RR 2.6 (2.3-3.1)), followed by airways (RR 2.6 (2.4-2.8)), tendons & muscles (RR 2.4 (2.2-2.6) and RR 1.4 (1.1-1.7)), and joints (RR 1.7 (1.3-2.1)), without a difference in median age at diagnosis. The data from the histopathological laboratory suggested a higher disease burden related to oncology for the LR compared to MB (OR 1.2, 95% CI 1.0-1.3). Oncological diagnoses were made at a younger age in the LR (8.8 versus 9.4 years). The disease burden was significantly higher for the LR than MB, but these results may suffer from substantial bias such as selection bias towards the database, and different behaviour of LR versus MB owners with regards to veterinary care. In the future, longer term population data can corroborate these results.

PETscan: measuring incidence of disease phenotypes to prioritize genetic studies in companion animals.

Reliable incidence measurement of diseases is necessary for identification of hereditary diseases in companion animal populations. The data collection system 'PETscan' was developed to facilitate standardized registration of diagnoses in veterinary practice. In the development, we attempted to counter challenges known from other primary practice data systems. PETscan includes a comprehensive list of potential diagnoses and supports the veterinary professionals in the diagnostic process. Demographics, individual data and standardized diagnostic data are collected through practice management software in a central database for epidemiological analysis. A preliminary data analysis from PETscan showed specific health issues in four canine breeds. As a real-time prospective monitoring tool, PETscan summaries can objectively assess the incidence of disorders in companion animal populations and can be used to prioritize disease-gene identification studies and evaluate the effects of breeding strategies, for example, after implementation of a new DNA test in the breeding strategy.

Heterozygosity testing and multiplex DNA panel screening as a potential tool to monitor health and inbreeding in a small, closed dog population.

BACKGROUND: Selective breeding in populations with a limited effective population size may result in a loss of genetic diversity, which can cause an increased concentration of specific disease liability genes. The Dutch Shepherd Dog (DSD) in the Netherlands is an example of such a breed with a small effective population. OBJECTIVE: To evaluate the measurement of genetic diversity and multiplex DNA panel screening for implementation in a breeding strategy for the Dutch Shepherd Dog (DSD) and to investigate the clinical relevance of potentially identified mutations in the multiplex DNA panel screening. RESULTS: Genome-wide SNP testing showed genetic isolation and reduced genetic diversity within coat variety subgroups of the DSD. Panel screening identified a Von Willebrand's Disease type I mutation. Although decreased Von Willebrand's Factor proteins were significantly lower in DSDs carrying the VWD-I allele compared to the wildtype, clinical follow-up did not show a significant association between the clinical phenotype and VWD-I genotype. CONCLUSIONS: Genetic relationship measurement within a breed population may be a useful tool to enable breeding strategies to conserve genetic diversity. Results from a disease panel screening need to be evaluated for clinical relevance before breed selection restrictions can be considered.

Disease burden in four populations of dog and cat breeds compared to mixed-breed dogs and European shorthair cats.

Current public and professional opinion is that many dog breeds suffer from health issues related to inherited diseases or extreme phenotypes. The aim of this historical comparative observational study was to evaluate the breed-related disease burden in three purebred dog populations (Chihuahua, French bulldog, Labrador retriever) and one purebred cat breed (Persian cats) in the Netherlands by comparison to a control population of mixed-breed dogs and European Shorthair cats. A qualitative query was performed, consisting of a literature review and collecting the expert opinions of University veterinary specialists, to gather insight into potential diseases of the study population. Next, a referral clinic case control study of the patients referred to specific medical disciplines in the University Clinic was performed. The odds ratio (OR) was calculated to determine the likelihood of a patient referred to a particular medical discipline being a certain breed. Together, the qualitative query and the case control study resulted in a list of potentially relevant diseases limited to five organ systems per breed. These were analysed in data from primary practices. Patient files from ten primary practices over a period of two years were manually extracted and examined. Four-hundred individual patient records per breed as well as 1000 non-breed records were randomly selected from the 10 practices, weighted per practice size. Records were then examined and the presence or absence of certain diseases was identified. To evaluate the disease burden per breed, proportional difference (PD) was estimated, as well as the animal's age at presentation in months. The results of the referral clinic case control study showed an overrepresentation (Odds Ratio>1.5) of the selected breeds in several medical specialties, while median age at presentation was in some cases significantly lower than in the non-breed animals. Results of the practice-based extended cross-sectional study showed that only a few of the selected diseases contribute to the disease burden in these purebred populations, which was different from the expectations derived from the literature or expert opinion. Additional results included age difference at presentation, which may be interpreted as age of onset, and could indicate a higher disease burden for the individual animal. Also, only a small percentage of purebred dogs was registered with the national kennel club. Our final recommendation is that population-based data mining is needed to evaluate country-specific companion animal health and welfare.

IL-10 promotor haplotypes associated with susceptibility to and severity of bacterial corneal ulcers.

Interleukin-10 plays an important role in modulating inflammation and antimicrobial defences. In animal models for bacterial corneal ulcers, high IL-10 levels were associated with a better clinical outcome. We investigated whether IL-10 promotor haplotypes, known to determine IL-10 expression in vitro, are associated with susceptibility to and/or clinical outcome of bacterial corneal ulcers in patients. IL-10 promotor polymorphisms C-819T, G-1082A, A-2763C, and A-2849G for 83 patients with bacterial corneal ulcers and 115 healthy controls were determined by restriction fragment length PCR analysis. For 63 patients and all healthy controls the most frequently occurring IL-10 promotor haplotypes were inferred from these data using the program SNPHAP. A significant underrepresentation of the A-2849A genotype was observed in patients as compared to healthy controls. Both the -2763A allele and the IL-10.1 promotor haplotype were associated with a poor clinical outcome, whereas a favourable clinical outcome was seen in patients carrying the IL-10.2 promotor haplotype. Together, IL-10 promotor haplotypes associated with low IL-10 levels seem to protect against the onset of bacterial corneal ulcers. Once a corneal ulcer has developed, patients carrying IL-10 haplotypes associated with a high IL-10 expression may have a favourable outcome.

Cytotoxic effect of sodium hypochlorite 0.5% (NaOCl) on ocular melanoma cells in vitro.

PURPOSE: Excision with or without adjuvant cryotherapy or brachytherapy is the treatment of choice in conjunctival melanoma. Adjuvant rinsing with alcohol or sodium hypochlorite peroperatively (Dakin's solution) is used in some centers to prevent seeding of melanoma cells. The purpose of this research is to compare the cytotoxicity of sodium hypochlorite (NaOCl) with other potential cytotoxic solutions in the treatment of conjunctival melanoma. METHODS: Three uveal melanoma cell lines (OCM8, Mel285, and Mel270) and one conjunctival melanoma cell line (CM2005.1) were tested in a proliferation test (CellTiter 96 AQueous One Solution Cell Proliferation Assay, Promega, Madison, WI). The 96-well plates were coated with melanoma cells and treated with sodium hypochlorite 0.5%, sodium bicarbonate (1.4% and 8.4%), ethanol 99%, or sodium chlorite during 3, 5, or 15 minutes. Each solution was tested in several dilutions. RESULTS: In all cell lines, no surviving cells were observed after treatment of 3 minutes with sodium hypochlorite. Ethanol 99% had a similar effect. A reduction of 70% of viable cells could be reached using sodium bicarbonate 1.4% or 8.4%. Water reduced the amount of viable cells by 40%. CONCLUSIONS: Sodium hypochlorite is cytotoxic for melanocytic cells in vitro. Its use may reduce local seeding of tumor cells and may decrease metastasis after extirpation of an extended ocular tumour. Further in vivo evaluation of sodium hypochlorite is required.

Lactoferrin Glu561Asp polymorphism is associated with susceptibility to herpes simplex keratitis.

Lactoferrin plays an important role in the defense against infections, including herpes simplex virus (HSV) keratitis. We studied the impact of three single nucleotide polymorphisms in the human lactoferrin gene on the susceptibility to HSV infections of the eye and the severity of such infections. Lactoferrin gene polymorphisms were determined by PCR combined with restriction fragment length analysis in 105 HSV keratitis patients and 145 control subjects. Bilateral tear samples were harvested from 50 patients and 40 healthy controls and tear lactoferrin concentrations were determined by ELISA. Patients' records were used to acquire information about the severity of the HSV keratitis. The frequencies of the Glu561Asp polymorphism, but not those of the Ala11Thr and Lys29Arg polymorphisms, differed significantly between patients and control subjects with an under-representation of the Asp561 allele in the patient group. Furthermore, the values for best corrected visual acuity, frequency of recurrences since onset, and average duration of clinical episodes did not differ among patients with various lactoferrin genotypes. In addition, tear lactoferrin concentrations were the same in patients with HSV keratitis and healthy controls and also did not differ among patients with various lactoferrin genotypes. Lactoferrin Glu561Asp polymorphism is associated with the susceptibility to HSV keratitis with a protective role for lactoferrin variants comprising Asp561. However, no beneficial effects of this lactoferrin variant on the clinical outcome of ocular HSV keratitis were noted.

Impression cytology of melanocytic conjunctival tumours using the Biopore membrane.

PURPOSE: To compare a new Biopore membrane impression cytology method with the routinely used exfoliative cytology in patients with a melanocytic lesion of the conjunctiva. METHODS: Sixty-eight consecutive patients with a conjunctival melanocytic lesion underwent Biopore membrane impression cytology as well as exfoliative cytology. A histologic sample was also available in 26 cases. All Biopore samples were stained immediately with RAL 555. Both Biopore and exfoliative cytology samples were assessed by two cytopathologists and graded into four different categories of atypia. RESULTS: Twenty-three out of 26 Biopores and 20 out of 24 for the exfoliative smears correlated with the corresponding histologic sample. Biopore cytology resulted in higher numbers of cells with a greater density compared to exfoliative cytology. CONCLUSIONS: Biopore cytology can be used for cytologic sampling of conjunctival melanocytic lesions. Because of the larger amount and higher density of cells obtained with the Biopore membrane, interpretation by a pathologist is easier and faster. Sampling of the fornix, caruncula, and ocular material in children is difficult with the Biopore method, and exfoliative cytology seems to be the favorable test in those situations.

A new model for limbal transplantation using E-GFP for follow-up of transplant survival.

Limbal transplants in humans show a high rate of rejection even under local and systemic immunotherapy. In order to test immunomodulatory treatments a new limbal transplant model in the rat was developed using enhanced green fluorescent protein (E-GFP) as marker for follow-up. Sixty E-GFP-positive limbal transplants from Sprague-Dawley TgN(act-EGFP)Osb4 rats were transplanted onto 18 wild-type inbred Sprague-Dawley (isografts) rats, six wild-type litter mate Sprague-Dawley (sibling) rats, 18 Fischer 344 (allografts) rats, and 18 Fischer 344 rats depleted from monocytes and macrophages by subconjunctival treatment with clodronate liposomes. All rats were monitored three times a week with fluorescence microscopy, until fluorescence had disappeared. At postoperative days 6, 9, 12, and 15, three rats of all groups were killed for immunohistochemical analysis of infiltrating cells. Using a modified digital fluorescence microscope, we were able to monitor transplant behavior over time without disturbance of the ocular surface. The average days of rejection were 14 days in the isograft group, the sibling group, and the untreated allograft group. However, the average day of rejection in the allogeneic macrophage-depleted group was 27 days. Marked infiltration of macrophages and lymphocytes was seen in the untreated isografts and allografts. In the clodronate liposome-treated allografts infiltration was minor. A successful new limbal transplant model is described. The transplant can be accurately followed up in vivo by E-GFP labeling of the donor tissue without disturbing the corneal surface. Although E-GFP itself proved to be immunogenic, local clodronate liposome injections significantly increased graft survival. So the model seems to be useful for testing immunosuppressive or modulatory agents in limbal transplantation studies.

Immunophenotypic markers to differentiate between benign and malignant melanocytic lesions.

BACKGROUND/AIMS: The authors investigated the expression of S100A1, S100A6, S100B, MelanA, and CEA in conjunctival naevi, primary acquired melanosis (PAM), conjunctival melanoma, and uveal melanoma in order to assess their potential usefulness in the pathological differential diagnosis of these entities. METHODS: Paraffin embedded sections of 18 conjunctival naevi, 14 PAM, 16 conjunctival melanomas, and 20 uveal melanomas were immunostained for S100A1, S100A6, S100B, MelanA, and CEA, and expression was scored semiquantitatively. RESULTS: Expression of S100A1 differed significantly between conjunctival naevi and conjunctival melanoma, with percentages of positive cells of 30.6% and 71.4%, respectively. Conjunctival melanomas had high average scores for S100A1 and S100B (71.4%, 62.9%, respectively), while uveal melanomas also had high S100A1 but low S100B scores (88.5%, 18.5%, respectively). MelanA was highly variable; naevi and uveal melanoma had higher average scores than conjunctival melanoma. CEA was hardly detectable in all four groups. CONCLUSION: S100A1 seems to be a possible candidate to differentiate conjunctival naevi from conjunctival melanoma. S100B seems to differentiate between uveal melanoma and conjunctival melanoma. However, the study size was small and therefore the data have to be confirmed by others.

111In-tropolonate labelled platelets; studies in normals and in patients with thrombocytopenia.

Human platelets were labelled with aqueous 111In-tropolonate in comparison with 111In-oxinate. In normals the labelling efficiency with 111In-tropolonate was higher (93% +/- 2%) than with 111In-oxinate (67% +/- 8%) (P less than 0.05). In cases of severe thrombocytopenia, lower labelling efficiencies were obtained. In six normals a mean platelet life of 9 days +/- 3 days and an initial recovery of 59% +/- 15% were obtained. In twelve patients with thrombocytopenia the mean platelet life was 4 days +/- 4 days and the initial recovery was 58% +/- 20%. The absolute uptake of radioactivity in spleen and in liver in both groups are reported.