Evisceration with implantation of an intrascleral silicone prosthesis in dogs: A retrospective study of 107 cases (2010-2019).

OBJECTIVE: To retrospectively analyze the preoperative clinical characteristics and surgical outcomes of evisceration with implantation of an intrascleral silicone prosthesis (EIISP) procedures in dogs and evaluate whether brachycephalic dogs are more prone than non-brachycephalic dogs to develop postoperative complications after EIISP. ANIMAL STUDIED: Ninety-One dogs (19 of which were brachycephalic) were included. PROCEDURES: Medical records from 2010 to 2019 were reviewed. Signalment, reason for EIISP, postoperative complications, follow-up time, and postoperative eye appearance were analyzed. RESULTS: The most frequently represented breeds were French Bulldog [11/91 (12%) dogs], Jack Russell Terrier [6/91 (7%)], and Shih Tzu [6/91 (7%)]. Brachycephalic dogs were statistically younger than non-brachycephalic dogs at the time of EIISP (p = 1.61 × 10-5 ). Uncontrolled glaucoma was the most common reason for EIISP in both groups. Short-term complications (from D0 to D15) seen in 7/91 (8%) dogs included epithelial corneal ulcers (n = 3), keratoconjunctivitis sicca (KCS) (n = 2), and prosthesis extrusion (n = 2). Long-term complications seen in 26/91 (29%) dogs included KCS (n = 11), epithelial corneal ulcers (n = 7), stromal ulcers (n = 3), entropion (n = 4), and prosthesis extrusion (n = 1). Extrusion of the prosthesis occurred twice in eyes that had undergone diode laser transscleral cyclophotocoagulation. The risk of postoperative complications was not significantly different between brachycephalic and non-brachycephalic dogs (p = .3). CONCLUSIONS: Brachycephalic status in dogs does not appear to influence the risk of complications from EIISP. Nevertheless, the present study is a reminder that EIISP focuses on esthetics, and considering the possible complications associated with it, it does not provide a benefit to the patient compared to enucleation.

Association of serum 25-hydroxyvitamin D concentrations with Schirmer tear test 1 and tear film breakup time in dogs.

BACKGROUND: The association between vitamin D and canine keratoconjunctivitis sicca (KCS) has not been investigated in dogs. OBJECTIVES: To investigate the association of serum 25-hydroxyvitamin D [25(OH)D] concentrations with Schirmer tear test 1 (STT-1) and tear film breakup time (TFBUT) in dogs. METHODS: Sixty-one clinically healthy, client-owned dogs were enrolled. STT-1 and TFBUT were measured in 122 (61dogs) and 82 (41 dogs out of total 61 dogs) eyes, respectively. Serum 25(OH)D concentrations were evaluated by quantitative chemiluminescent immunoassay. The dogs were classified into 6 groups according to the evaluations (STT-1: group 1, normal [≥ 15 mm/min] in both eyes; group 2, normal in one eye and abnormal [< 15 mm/min] in the fellow eye; group 3, abnormal in both eyes; TFBUT: group 4, normal [≥ 20 sec] in both eyes; group 5, normal in one eye and abnormal [< 20 sec] in the fellow eye; group 6, abnormal in both eyes). RESULTS: STT-1 was positively correlated with TFBUT (p < 0.001). Among the STT-1 groups, the mean serum 25(OH)D concentration in group 1 was significantly higher than in groups 2 and 3 with positive correlation (p < 0.001). However, there were no significant differences among the TFBUT groups 4, 5, and 6. CONCLUSIONS: In dogs, it was found that serum 25(OH)D concentrations had a greater effect on quantitative KCS than qualitative KCS. Therefore, it is considered that measurement of serum 25(OH)D concentration could be included in the diagnostic tests in canine quantitative KCS patients.

A review of diagnostic tests for qualitative and quantitative tear film deficiency in dogs.

Dry eye disease (DED) is a complex multifactorial condition caused by loss of ocular surface homeostasis from quantitative and/or qualitative tear film deficiency. Schirmer tear test (STT) is often the only diagnostic test used to assess for DED in veterinary practice. STT is invaluable in the diagnosis and monitoring of quantitative tear film deficiency (i.e., keratoconjunctivitis sicca); however, it is not sufficient to optimize therapy and fully recognize other contributing factors for the disturbance in ocular surface homeostasis. The present work reviews diagnostic tests for assessing aqueous tear production in veterinary medicine, as well as the quality of tears, corneal epithelial barrier integrity, and the lacrimal functional unit.

Long-lasting otic medications may be a rare cause of neurogenic keratoconjunctivitis sicca in dogs.

OBJECTIVE: To characterize the clinical course and long-term prognosis of a suspected novel cause of neurogenic keratoconjunctivitis sicca (nKCS) secondary to florfenicol, terbinafine hydrochloride, mometasone furoate (Claro and Neptra) or florfenicol, terbinafine, betamethasone acetate (Osurnia). ANIMALS: 29 client-owned dogs. PROCEDURES: Online survey and word-of-mouth recruitment were conducted to identify dogs that developed clinical signs of nKCS after application of otitis externa medication containing terbinafine and florfenicol. A retrospective analysis of medical records of dogs meeting inclusion criteria was then conducted. Included dogs had onset of clinical signs of nKCS within 1 day after application of otitis externa medications containing terbinafine and florfenicol and had documentation of low Schirmer tear test value (< 15 mm/min) of affected eyes. RESULTS: 29 dogs with medical records available for review met the inclusion criteria. Documented return of clinically normal tear production was identified in 24 of 29 dogs, with a median time from application of ear medication to documented return of clinically normal tear production of 86 days (range, 19 to 482 days). A corneal ulcer was diagnosed in 68% (20/29). Multivariable Cox regression analysis showed being referred to an ophthalmologist (P = .03) and having a deep ulcer (P = .02) were associated with a longer time to documentation of Schirmer tear test ≥ 15 mm/min. CLINICAL RELEVANCE: Dogs that developed nKCS within 1 day after application of otitis externa medications containing terbinafine and florfenicol had a good prognosis for return of normal tear production within 1 year.

Changes in tear production in a dog with keratoconjunctivitis sicca for a year after inevitable nictitating membrane gland resection due to suspicion of a malignant tumour.

Since the removal of the NM causes KCS in dogs, it was contraindicated to remove the NM unless unavoidable such as in a malignant tumour. However, to the best of author's knowledge, there are no reports of conjunctivitis and keratitis owing to decreased tear production following removal of the NM gland. This case study demonstrates the tear production changes in a dog for a year after removal of the nictitating membrane (NM) due to suspicion of a malignant tumour. A 13-year-old spayed female English Cocker Spaniel who had suffered from severe ocular discharge, discomfort, keratoconjunctivitis sicca (KCS), and NM enlargement in the right eye was brought to our hospital. The dog could not tolerate treatment with topical 0.2% cyclosporine or corticosteroids. The dog's right eye had NM gland prolapse, severe follicular conjunctivitis and a very low Schirmer tear test-1 (STT-1) value of 3 mm/min. Furthermore, the result of fine needle aspiration of the enlarged NM gland suggested a risk of malignancy. Despite the risk of KCS, complete NM resection was performed to diagnose the tumour. Fortunately, the final histopathological evaluation revealed chronic inflammation without any evidence of malignancy. Contrary to concerns that the STT-1 value would further decrease after the removal of the NM gland, the STT-1 value remained elevated compared to that before surgery, and the clinical symptoms improved for a year. It is generally known that NM gland resection is not recommended due to the risk of developing iatrogenic KCS unless a malignant tumour is suspected. In this case, surgical removal of the inflammatory NM gland that was not responsive to medications had a positive effect on KCS. Since the inflammatory and structural disease of the NM was strengthening KCS, the outcome was thought to be different from that when the normal third eyelid was removed.

Topical applications of allogeneic adipose-derived mesenchymal stem cells ameliorate the canine keratoconjunctivitis sicca.

BACKGROUND: Canine keratoconjunctivitis sicca (KCS) is predominantly an immune-mediated disease. Current therapy of canine KCS is mainly by immunosuppressant, but the effectiveness was limited in some patients. In the past few years, some studies showed the results of the use of mesenchymal stem cells in treating canine KCS via periocular injections. However, the periocular injection procedure requires sedation or general anesthesia, and may lead to iatrogenic or incidental injury during the injection process. The aim of this study was to investigate the efficacy of topical allogenic canine adipose-derived mesenchymal stem cells (cAD-MSCs) in clinical patients of canine KCS. RESULTS: The cAD-MSCs used in this study were characterized for their capability of tri-lineage differentiation and immunomodulatory properties. In addition, preparation methods for eye drops of cAD-MSCs was developed and its optimal preservation was tested. The canine KCS patients were recruited for clinical trial and divided into two groups based on their history of previous treatment. All patients received topical cAD-MSCs treatment once per week for 6 consecutive weeks and complete ophthalmic examinations were performed 1 week before treatment (week 0) and at 3rd, 6th, 9th weeks, respectively. The results showed that the quantity and quality of tears have improved significantly following topical cAD-MSCs treatment based on Schirmers tear test-1 and tear break-up time. More than half of all patients were found improved in the tear quantity. In particular, 56.5% of the patients that were unresponsive to prior immunosuppressant therapy had an effective increase in tear volume. The severity of clinical signs was also ameliorated according to the numeric rating scale score from both patient owners and the clinician. CONCLUSION: To sum up, topical cAD-MSCs may be beneficial especially in KCS patients with poor owner compliance for frequent daily use of eye drops or those who are unresponsive to immunosuppressant therapy.

Neurogenic keratoconjunctivitis sicca in 34 dogs: A case series.

OBJECTIVE: To describe the clinical findings, imaging features, underlying conditions, treatment, and progression of dogs presented between 2010 and 2019 with neurogenic keratoconjunctivitis sicca (NKCS). METHODS: Dogs diagnosed with NKCS were searched in the clinical database. Inclusion criteria were STT-1 readings <15 mm/min, clinical signs of KCS with concurrent ipsilateral xeromycteria. RESULTS: Thirty-four cases were identified. Mean age at presentation was 8.2 years, median 8.9 years (0.3-14.7). Twenty dogs were male, and 14 dogs were female. Concurrent neurological deficits included facial neuropathy (n = 13, 38%), peripheral vestibular syndrome (n = 10, 29%), and Horner's syndrome (n = 5, 15%). Advanced imaging was acquired in 53% of cases (n = 18). Etiologies included idiopathic (n = 18, 53%), endocrinopathy (n = 6, 18%), otitis interna (n = 4, 12%), head trauma (n = 3, 9%), iatrogenic (post-TECA-LBO, n = 1, 3%), brainstem mass (n = 1, 3%), and an area of inflammation in the pterygopalatine fossa (n = 1, 3%). Treatment for NKCS was initiated in most cases (n = 30, 88%) including: oral pilocarpine 2% and lacrimostimulant (n = 19), oral pilocarpine 2% only (n = 3), or lacrimostimulant only (n = 8). A mean time follow-up of 3.7 months, median 3 months (1-14) was available in 23 cases (68%). Eleven cases with follow-up were responsive (48%) with resolution of the clinical signs in a median time 4 months (1-10), and all of them were treated with oral pilocarpine (±lacrimostimulant). CONCLUSIONS: Most cases presented as idiopathic NKCS; in others, an underlying cause of facial neuropathy was identified. All responsive cases were treated with oral pilocarpine 2%.

Assessment of tear film osmolarity using the IPen® Vet osmometer in Pug and Shih-Tzu dogs with and without keratoconjunctivitis sicca.

OBJECTIVE: To establish tear film osmolarity (TFO) values in Pugs and Shih-Tzus, with and without keratoconjunctivitis sicca (KCS). ANIMALS STUDIED: A total of 82 adult dogs were evaluated. PROCEDURE: The inclusion criteria for the healthy group was a Schirmer tear test (STT-1) ≥15 mm/min with no clinical signs of KCS, whereas those with KCS had clinical signs and a STT-1 ≤10 mm/min. All animals underwent complete ophthalmological evaluation prior to STT-1 and TFO. Student's t tests were used to compare STT-1 and TFO in KCS and healthy eyes as well as possible differences in TFO between breeds. In addition, a linear regression to model the relationship between the two variables (STT-1 and TFO) was performed. A P-value ≤ 0.05 was considered statistically significant. RESULTS: STT-1 results were significantly lower (p = 0.0001) in the KCS group (4.46 ± 1.74) compared with the control group (18.80 ± 2.02). Mean TFO results were significantly higher in the KCS group (353.02 ± 16.58 mOsm/L) (p < 0.0001) compared with the control group (315.27 ± 6.15 mOsm/L). The formula Y = 365.059-2.625 * X significantly predicts (p < 0.001) the value of the variable Y (TFO mOsm/L) as a function of the variable X (STT-1 mm/min), with a coefficient of determination of 0.71. CONCLUSIONS: The results revealed differences in TFO and STT-1 between KCS and healthy dogs. Additionally, STT-1 and TFO values were correlated with the aim to use STT-1 values to predict TFO values in brachycephalic breeds.

Oral mucosa transplantation may improve tear film osmolarity in dogs with keratoconjunctivitis sicca - a preliminary study / [Transplante da mucosa oral na melhoria da osmolaridade do filme lacrimal em cães com ceratoconjuntivite seca - estudo preliminar]

The objective of this study was to evaluate the use of cyclosporine 1% alone or associated with oral mucosa transplantation (OMT) in dogs with dry keratoconjunctivitis (KCS). Schirmer Tear Test (STT-1) and Tear Film Osmolarity (TFO) were measured in both eyes of 30 adult dogs (before and 45 days after treatment. The animals were divided into three groups (10 dogs for group): control (normal dogs), group I (GI, treated with 1% cyclosporine alone), and group II (GII, treated with 1% cyclosporine and OMT). All STT-1 and TFO values were subjected to the Shapiro-Wilk normality test, and all were normally distributed. STT-1 and TFO values before and after treatment were subjected to the T-Student Test. The STT­1 and TFO values of the right eye were subjected to Repeated Measures ANOVA followed by a Tukey Test for comparison between groups I and II. Means with a value of p≤0.05 were considered significant. There was a decreased osmolarity in both groups after treatment. Mean osmolarity in GII (322.60±16.56 mOsm/L) was significantly lower than GI (336.40±5.66 mOsm/L). The OMT associated with cyclosporine 1% improved the osmolarity of the tear film in dogs with KCS with a seeming synergism between the clinical and surgical treatments.(AU)

Avaliou-se o uso de ciclosporina 1% isolada ou associada ao transplante de mucosa oral (TMO) em cães com ceratoconjuntivite seca (CCS). O teste lacrimal de Schirmer (TLS-1) e a osmolaridade do filme lacrimal (OFL) foram medidos em ambos os olhos, em 30 cães adultos, antes e 45 dias após o tratamento. Os animais foram divididos em três grupos (10 cães por grupo): controle (cães saudáveis), grupo I (GI, tratados apenas com ciclosporina 1%) e grupo II (GII, tratados com 1% de ciclosporina associada ao TMO). Todos os valores do TLS-1 e da OFL foram submetidos ao teste de normalidade Shapiro-Wilk, e todos foram distribuídos normalmente. Os valores de TLS-1 e OFT antes e depois do tratamento foram submetidos ao teste T-Student. Os valores TLS-1 e OFT do olho direito foram submetidos à ANOVA de medidas repetidas, seguida por um teste de Tukey para comparação entre os grupos I e II. Valor de P≤0,05 foi considerado significativo. Houve uma diminuição da osmolaridade em ambos os grupos após o tratamento. A osmolaridade média no GII (322,60±16,56 mOsm/L) foi significativamente inferior à no GI (336,40±5,66 mOsm/L). O TMO associado à ciclosporina 1% melhorou a osmolaridade do filme lacrimal em cães com CCS, com uma sinergia aparente entre os tratamentos clínicos e cirúrgicos.(AU)

Study shows there are lots of dry eyes in the house.

Georgina Mills reports on research that examines the frequency and breed-related risk factors for keratoconjunctivitis sicca in dogs.

Keratoconjunctivitis sicca in dogs under primary veterinary care in the UK: an epidemiological study.

OBJECTIVES: To estimate the frequency and breed-related risk factors for keratoconjunctivitis sicca (KCS) in dogs under UK primary veterinary care. METHODS: Analysis of cohort electronic patient record data through the VetCompass Programme. Risk factor analysis used multivariable logistic regression. RESULTS: There were 1456 KCS cases overall from 363,898 dogs [prevalence 0.40%, 95% confidence interval (CI) 0.38-0.42] and 430 incident cases during 2013 (1-year incidence risk 0.12%, 95% CI 0.11-0.13). Compared with crossbreds, breeds with the highest odds ratio (aOR) for KCS included American cocker spaniel (aOR 52.33: 95% CI 30.65-89.37), English bulldog (aOR 37.95: 95% CI 26.54-54.28), pug (aOR 22.09: 95% CI 15.15-32.2) and Lhasa apso (aOR 21.58: 95% CI 16.29-28.57). Conversely, Labrador retrievers (aOR 0.23: 95% CI 0.1-0.52) and border collie (aOR 0.30: 95% CI 0.11-0.82) had reduced odds. Brachycephalic dogs had 3.63 (95% CI 3.24-4.07) times odds compared to mesocephalics. Spaniels had 3.03 (95% CI 2.69-3.40) times odds compared to non-spaniels. Dogs weighing at or above the mean bodyweight for breed/sex had 1.25 (95% CI 1.12-1.39) times odds compared to body weights below. Advancing age was strongly associated with increased odds. CLINICAL SIGNIFICANCE: Quantitative tear tests are recommended within yearly health examinations for breeds with evidence of predisposition to KCS and might also be considered in the future within eye testing for breeding in predisposed breeds. Breed predisposition to KCS suggests that breeding strategies could aim to reduce extremes of facial conformation.

Interferon therapies in small animals.

Interferons (IFNs) are cytokines that play an important role in the immune response of animals and humans. A number of studies reviewed here have evaluated the use of human, canine and feline IFNs as treatments for infectious, inflammatory and neoplastic disease in dogs and cats. Recombinant canine IFN-γ is deemed an efficacious therapy for canine atopic dermatitis. Recombinant feline IFN-ω is effective against canine parvoviral enteritis and has also been recommended for canine atopic dermatitis. Based on limited evidence, recombinant canine IFN-α could be a topical treatment option for dogs with gingivitis and keratoconjunctivitis sicca. Conclusive evidence is lacking for other diseases and large randomised controlled trials are needed before IFNs can be recommended for other indications.

The Impact of Surgical Excision of the Orbital Lacrimal Gland on the Aqueous Tear Production and Ocular Surface Health in Donkeys (Equus asinus).

The exact contribution of the orbital lacrimal gland (OLG) is unknown and is still a subject of debate and inconsistency in literature. Currently, there are no detailed studies addressing the influence of the OLG removal on tear production in equines. This study aimed to address the influence of surgical excision of the OLG on aqueous tear production and ocular surface health in donkeys. The study was conducted on six clinically healthy donkeys with no ophthalmic abnormalities. In each donkey, the OLG of the left eye was surgically excised, whereas the right eye was served as a control. External ophthalmic examination, Schirmer tear test (STT) I and II, tear pH, fluorescein staining test were conducted on both eyes, preoperatively and at one-week intervals for 60 days, postoperatively. There were significant decreases in STT I and II values (P = .0001 and .0001, respectively), whereas tear pH values showed a significant increase (P = .0001) in the operated eyes compared with the control ones. There were no overt clinical signs characteristics of keratoconjunctivitis sicca (KCS) in the operated eyes. However, there was evidence of microinjury of the keratoconjunctival epithelium evidenced by positive fluorescein uptake, postoperatively. Surgical excision of the OLG significantly diminished the aqueous tear production and threatened the corneal epithelium as a result of corneal dehydration. On the contrary to the recommendations of other studies, eyes subjected to this procedure should receive treatment of dry eye to prevent development of KCS, postoperatively.

Efficacy of adjunctive therapy using Vizoovet in improving clinical signs of keratoconjunctivitis sicca in dogs: A pilot study.

OBJECTIVE: To assess the clinical safety and efficacy of adjunctive therapy using Vizoovet to ameliorate clinical signs of keratoconjunctivitis sicca (KCS) in dogs. ANIMALS STUDIED: Twenty client-owned dogs. PROCEDURES: Canine patients diagnosed with KCS were enrolled in this prospective study. Patients were randomly selected to receive either Vizoovet or GenTeal drops twice daily in addition to twice daily tacrolimus 0.03% solution. Data were collected from only one eye of each patient and included STT-1, IOP, TFBUT, and results of objective clinical scoring performed by pet owners. Statistical significance was set at P ≤ .05. RESULTS: In all, 20 dogs (20 eyes) were enrolled in this prospective randomized study. Females (n = 12; 60%) outnumbered males (n = 8; 40%) and all dogs were spayed/neutered. Mean age of all dogs was 10.6 ± 3.79 years. In both treatment groups, the improvement in STT-1 values over the course of the study was significant (P = .002). When comparing the STT-1 improvements between groups, no significance was found (P = .78). In both groups, the improvement in TFBUT was significant (P = .0018). When comparing the TFBUT improvements between groups, no significance was found (P = .14). Squinting, rubbing, ocular discharge, and medication administration scores all significantly improved throughout the course of the study; however, they did not differ significantly between groups. Throughout the study, no adverse side effects were noted clinically or by the pet owner in either group. CONCLUSIONS AND CLINICAL RELEVANCE: Adjunctive treatment with Vizoovet was as safe and effective as GenTeal drops at improving clinical signs of dry eye in dogs.

Clinical-dosimetric relationship between lacrimal gland dose and keratoconjunctivitis sicca in dogs with sinonasal tumors treated with radiation therapy.

BACKGROUND: Dogs with sinonasal tumor can develop keratoconjunctivitis sicca (KCS) after radiation therapy (RT). In humans, the incidence of xerophtalmia is associated with the mean radiation dose received by the ipsilateral lacrimal gland (LG). HYPOTHESIS/OBJECTIVES: The eyes receiving a higher mean LG dose are more likely to develop KCS. The aim of the study was to determine a starting threshold dose to use as dose constraint for intensity-modulated radiation therapy (IMRT). ANIMALS: Dogs with nasal tumors treated with RT between August 2013 and December 2016. METHODS: Case control retrospective study of dogs with sinonasal tumor treated with 42 Gray (Gy) in 10 fractions using IMRT. Dogs were included if development of KCS after RT was documented (cases) or adequate follow-up information with Schirmer tear test (STT) result for ≥6 months after RT was available (controls). Lacrimal glands were contoured and dose distribution was calculated using the original treatment plan to determine prescribed doses to LGs. RESULTS: Twenty-five dogs were treated with RT and 5 dogs (20%) developed KCS. Fifteen dogs met the inclusion criteria including 5 unilateral KCS and 10 control dogs, resulting in 5 KCS eyes and 25 control eyes. KCS developed at a median of 111 days (84-122) after 1st RT. The mean LG dose reached using a 4.2 Gy per fraction was 33.08 Gy (range: 23.75-42.33) for KCS eyes and 10.33 Gy (1.8-24.77) for control eyes (P < .001). The minimum LG mean dose for developing KCS was 23.75 Gy. No eyes that received a mean LG dose <20 Gy developed KCS versus 5/7 (71%) developed with >20 Gy. CONCLUSION AND CLINICAL IMPORTANCE: Contouring and applying a dose constraint on LGs should be performed when using IMRT in dogs with sinonasal tumors to reduce the risk of KCS.

Antimicrobial susceptibility and minimal inhibitory concentration of bacteria isolated from the eyes of dogs with keratoconjunctivitis sicca / Susceptibilidade antimicrobiana e concentração inibitória mínima de bactérias isoladas dos olhos de cães com ceratoconjuntivite seca

The objective of this study was to evaluate the antimicrobial susceptibility profile of bacteria isolated from the eyes of dogs with keratoconjunctivitis sicca (KCS). We evaluated 65 dogs diagnosed with KCS and 30 healthy dogs (Control Group). Conjunctival swab samples were collected after KCS was diagnosed. Microbiological examinations were performed, including aerobic culture, antimicrobial susceptibility testing and minimum inhibitory concentration (MIC) determination for chloramphenicol, tobramycin, ofloxacin and moxifloxacin. MICs of the fifteen most resistant strains of Staphylococcus pseudintermedius (Staphylococcus intermedius Group, SIG) and the fifteen most resistant strains of gram-negative bacteria were determined. By percentage, the microorganisms exhibited the highest susceptibility to polymyxin B, tobramycin and chloramphenicol and the lowest to tetracycline. Three multi-drug-resistant strains of SIG were detected: one displayed isolated susceptibility to cefazolin, another to vancomycin, and another to polymyxin B and amikacin. The species of bacteria isolated from the eyes of dogs with KCS presented variable susceptibility to the antibiotics tested. We found evidence of the emergence of quinolone-resistant strains of SIG and further evidence of increased ocular prevalence. These findings reinforce the need to identify the bacteria involved and their antimicrobial susceptibility profile, as secondary infections can serve as exacerbating and perpetuating factors in KCS.(AU)

O objetivo deste estudo foi avaliar o perfil de susceptibilidade antimicrobiana de bactérias isoladas de olhos de cães com ceratoconjuntivite seca (CCS). Foram avaliados 65 cães com diagnóstico de CCS e 30 cães saudáveis ​​(Grupo Controle). Depois do diagnosticado de CCS, suabes conjuntivais foram coletados. Exames microbiológicos foram realizados, incluindo cultura aeróbia, teste de susceptibilidade antimicrobiana e determinação da concentração inibitória mínima (CIM) para cloranfenicol, tobramicina, ofloxacina e moxifloxacina. Para determinar a CIM, foram selecionadas as quinze cepas mais resistentes de Staphylococcus pseudintermedius (Staphylococcus intermedius Group-SIG) e as quinze cepas mais resistentes de bactérias gram-negativas. Os microrganismos apresentaram maior suscetibilidade percentual à polimixina B, tobramicina e cloranfenicol e menor suscetibilidade à tetraciclina. Três cepas de SIG resistentes a múltiplos medicamentos foram detectadas, do quais um demonstrou suscetibilidade isolada à cefazolina, outro à vancomicina e outro à polimixina B e à amicacina. As espécies de bactérias isoladas dos olhos de cães com CCS apresentaram suscetibilidade variável aos antibióticos testados. Encontramos evidências do surgimento de cepas resistentes à quinolona de S. pseudintermedius e outras evidências de aumento da prevalência ocular. Esses achados reforçam a necessidade de identificar as bactérias envolvidas e seu perfil de susceptibilidade aos antimicrobianos, pois as infecções secundárias podem servir como fatores exacerbantes e perpetuantes na CCS.(AU)

Comprehensive Clinical, Diagnostic, and Advanced Imaging Characterization of the Ocular Surface in Spontaneous Aqueous Deficient Dry Eye Disease in Dogs.

PURPOSE: To perform a comprehensive clinical, diagnostic, and imaging characterization of the ocular surface in West Highland White Terriers (WHWTs) diagnosed with aqueous deficient dry eye (ADDE) disease. METHODS: Six ADDE-affected and 13 ADDE-unaffected WHWT dogs were enrolled and underwent clinical assessment and disease scoring, tear osmolarity, phenol red thread test, Schirmer tear test, tear film breakup time, fluorescein staining, Rose bengal and lissamine green vital dye staining, meibometry, corneal esthesiometry, ultrasound pachymetry, optical coherence tomography, in vivo confocal microscopy, and conjunctival biopsy. Subjective assessment of their condition was provided by owner-reported surveys. RESULTS: ADDE-affected WHWT dogs had higher median clinical disease (conjunctiva: 5.75 vs. 0.00; cornea: 14.00 vs. 5.00; total: 17.50 vs. 5.00), vital staining (Rose bengal: 2.25 vs. 1.50; lissamine green: 2.00 vs. 1.00), and histologic disease (conjunctiva: 2 vs. 0) scores when compared with the controls. In addition, ADDE-affected WHWTs had significantly lower phenol red thread test (5.0 vs. 17.5, mm/15 s), Schirmer tear test (3 vs. 20, mm/min), tear film breakup time (3.6 vs. 13.9, s) values and higher area under the curve values for meibometry (394 vs. 245, meibometry units [MU]). There were no significant differences in other tear film tests performed. Advanced imaging revealed decreased tear meniscus height (optical coherence tomography) and variable pigment deposition within corneal epithelial cells (in vivo confocal microscopy). CONCLUSIONS: This comprehensive assessment of ADDE-affected WHWTs depicts the ocular surface changes associated with quantitative lacrimal gland dysfunction. Importantly, ADDE-affected WHWTs may prove a valuable naturally occurring ADDE model for investigating underlying pathophysiological mechanisms and the development of novel therapeutics.

The Effect of Periocular Fatty Acids and 0.15% Hyaluronate Eye Drops Application on Keratoconjunctivitis Sicca in Dogs: An Exploratory Study.

The aim of this exploratory study was to evaluate the efficacy of a periophthalmic cream of a pool of fatty acids (FAG®) in association with 0.15% hyaluronate eye drops in alleviating the clinical symptoms of keratoconjunctivitis sicca (KCS) in a case series of dogs. The study was conducted on 10 dogs diagnosed with idiopathic KCS. All dogs had been previously treated with topical tobramycin alone, which had been ineffective in improving clinical signs. The affected eyes were treated with 2 applications daily of a periophthalmic cream of FAG® and 1 drop 3 times a day of 0.15% of hyaluronate eye drops for 8 weeks. Schirmer tear test I (STT I) values were recorded and ocular signs (conjunctival hyperemia, ocular discharge, corneal opacity, vascularization and pigmentation, and discomfort level) were collected, scored on a 3-point scale (grade 0, grade 1, and grade 2). Differences between scores and STT data recorded at baseline and at 8 weeks of therapy were statistically analysed. The effect of treatment was pronounced (increase in STT values by more than 4 mm/min, no signs of inflammation) in 8/18 eyes; moderate (increase in STT values of 3-4 mm/min or mild improvement in signs of corneal/conjunctival inflammation) in 3/18 eyes; and unsatisfactory in 7 of 18 eyes. Median of STT values significantly improved compared with baseline levels, while statistically significant decreases in clinical-sign scores of conjunctival hyperemia, ocular discharge, and discomfort were recorded. However, in moderate and advanced stages, reduction of neovascularization or corneal pigmentation was not observed throughout the treatment period. No noticeable adverse reactions were recorded. Preliminary results indicate that the application of periocular FAG and topical 0.15% hyaluronate eye drops may be a suitable treatment for KCS in dogs in selected cases. A larger comparative study is necessary to further confirm these findings.

Characterisation of corneal impression cytology in dogs and its application in the diagnosis of keratoconjunctivitis sicca.

OBJECTIVE: Determine morphological and morphometric parameters of corneal epithelium in dogs, and determine the cellular alterations that occur in canine keratoconjunctivitis sicca (KCS) using impression cytology. STUDY ANIMALS: 60 dogs divided into two groups: dogs with Schirmer tear test (STT) at least 15 mm/minute and absence of ocular disease, and dogs with STT less than 15 mm/minute and clinical signs of KCS. PROCEDURES: Impression cytology was used to collect corneal samples. The percentage of eyes with cell changes, the number of such cells and the percentage of cells with structural alterations in each group were determined. The possible correlation between corneal epithelium alterations and decreased tear production was evaluated. RESULTS: A significant positive correlation existed between STT and the area of the cytoplasm and nucleus of corneal cells. A significant negative correlation was found between STT ​​and the nucleus/cytoplasm ratio, and the presence of cellular changes. A significant difference existed between the numbers of pyknotic nuclei, being higher among animals with all stages of KCS. CONCLUSION: Corneal impression cytology can be used to assess the corneal epithelium in healthy eyes and eyes with KCS, demonstrating its usefulness as a diagnostic tool especially in mild and early cases.

Comparative efficacy of topical oclacitinib 0.1% and tacrolimus 0.01% in canine keratoconjunctivitis sicca.

OBJECTIVE: To assess the efficacy of 0.1% oclacitinib as a single agent, and in combination with tacrolimus 0.01%, for the control of ophthalmic signs of keratoconjunctivitis sicca (KCS) in dogs. ANIMALS STUDIED: Thirty-two dogs (57 eyes) diagnosed with idiopathic KCS were included. Inclusion criteria were Schirmer Tear Test 1 (STT-1) values <15 mm/min and concurrent clinical signs such as ocular hyperemia and discharge. PROCEDURES: The animals were submitted to a randomized, open-label, 5-week study and divided into 3 treatment groups treated with the following ophthalmic solutions: (a) 0.1% oclacitinib, (b) 0.1% oclacitinib +0.01% tacrolimus, and (c) 0.01% tacrolimus. Eye drops were instilled twice daily (12-hour intervals). At each follow-up examination, STT-1, clinical signs, and potential drug side effects were assessed. RESULTS: Oclacitinib did not significantly improve STT-1 values or clinical scores. Tacrolimus alone and in combination with oclacitinib increased mean STT-1 values by 11.84 ± 5.2 and 12.46 ± 5.3 mm/min, respectively (P = 0.0001). Clinical scores of ocular discharge and hyperemia also improved significantly in both groups receiving treatment with tacrolimus (P < 0.05). However, addition of oclacitinib to tacrolimus provided no additional improvement over tacrolimus alone. CONCLUSIONS: Topical 0.1% oclacitinib twice daily is not effective in controlling the ocular signs of KCS in dogs. 0.01% tacrolimus increased STT-1 values significantly and could potentially be used as a treatment for mild-to-moderate cases of KCS. Synergism between drugs did not occur, and therefore the use of oclacitinib is not justified in cases of canine KCS.