Effect of topical 0.02% tacrolimus aqueous suspension on tear production in dogs with keratoconjunctivitis sicca

Tacrolimus loaded nanostructured lipid carriers using Moringa oleifera seed oil: design, optimization and in-vitro evaluations

The proposed research aims to develop Tacrolimus-loaded nanostructured lipid carriers (TAC-loaded NLCs) to overcome poor aqueous solubility and dissolution rate to enhance its oral absorption. A central composite design was used to optimise the amount of Poloxamer 188 and D-α-Tocopherol-polyethylene-glycol-succinate (TPGS). The optimised TAC-loaded NLCs contain stearic acid (250 mg), Moringa oleifera (MO) seed oil (50 mg), TAC (Tacrolimus: 10 mg), TPGS (60 mg), and Poloxamer 188 (1% w/v) with a mean diameter of 393.3 ± 29.68 nm, a zeta potential of -18.3 ± 6.19 mV, high entrapment efficiency (92.12 ± 1.14% w/w), and desirability (0.989). TAC-loaded NLCs showed ∼12 times higher drug dissolution efficiency, while in-vitro anti-inflammatory studies showed ∼1.8 times lower IC50 (half-maximal inhibitory concentration) than TAC suspension. The lyophilised TAC-loaded NLCs were found to be stable after 3 months. Thus, the present study concludes the successful encapsulation of TAC in NLCs made of stearic acid and MO seed oil.

Topical Ocular Therapeutics in Small Animals

This article reviews the administration of common topical ophthalmic medications, in relation to factors influencing absorption including composition of topical ophthalmic preparations, and potential systemic effects. Commonly prescribed, commercially available topical ophthalmic medications are discussed with respect to pharmacology, their indications for use, and adverse effects. Knowledge of topical ocular pharmacokinetics is essential for the management of veterinary ophthalmic disease.

Impacts of exposure to topical calcineurin inhibitors on metabolism in vitiligo infants

BACKGROUND

Tacrolimus ointment is a recently developed topical immunomodulator that has been approved for use in patients with vitiligo older than 2 years. Concern regarding potential systemic toxic effects has limited treatment options for children younger than 2 years. We wanted to determine whether topical tacrolimus therapy is safe and effective in patients with vitiligo younger than 2 years.

METHODS

The present 6-month clinical trial was conducted to evaluate the efficacy and safety of 0.03% tacrolimus in the treatment of vitiligo in children under 2 years of age. Meanwhile, serum and urine samples were collected, and liquid chromatography-mass spectrometry was performed to generate the serum and urine metabolic profile data of patients and healthy controls.

RESULTS

The overall response rate at the sixth month, which was defined by the degree of re-pigmentation, was 100%. As revealed by blood monitoring and metabolite detection 6 months later, there was no difference between the treatment group and the control group. There is no evidence that long-term topical application of 0.03% tacrolimus ointment will cause metabolite or other physical changes in the body.

CONCLUSIONS

Tacrolimus ointment appears to be effective and safe in the treatment of vitiligo in children younger than 2 year.

TRIAL REGISTRATION

http://www.chictr.org.cn identifier: ChiCTR 2100045920.

IMPACT

We first reported the efficacy and safety of topical application of 0.03% tacrolimus ointment in infants with vitiligo characterized by the metabolites. There is no evidence that long-term topical application of 0.03% tacrolimus ointment will cause metabolite or other physical changes in the body. This study provide evidence for the TCI treatment of infants with vitiligo.

Comparison of topical 0.03% tacrolimus and homologous injectable platelet-rich plasma in the treatment of keratoconjunctivitis sicca in dogs

Background and Aim

Keratoconjunctivitis sicca (KCS) is predominantly an immune-mediated chronic inflammatory ocular disease that is commonly diagnosed in dogs. This study aimed to compare the conventional use of topical immunosuppressant tacrolimus 0.03% eye drops and a new therapy injectable homologous platelet-rich plasma (HPRP) into the third eyelid gland and inferior and superior palpebral conjunctiva of dogs with KCS.

Materials and Methods

A total of 66 eyes from 33 dogs were evaluated. The eyes were divided into three equal groups: Negative control group, tacrolimus group (TG), and homologous platelet-rich plasma group (HPRPG). The animals were evaluated using the Schirmer's tear test-1 (STT-1), osmolarity test (OT), strip meniscometry test (SMT), tear film break-up test (TBUT), fluorescein test, lissamine green test (LGT), and cytological and histopathological analyses.

Results

In TG, there was a significant increase (p < 0.05) in the STT-1 and SMT values, and goblet cell count in the palpebral conjunctiva by the end of the study. In HPRPG, 36% (four dogs) received three applications, 55% (six dogs) received two applications, and 9% (one dog) received one application before the initial ocular signs improved. There was a significant decrease (p < 0.05) in the lymphocyte and neutrophil counts of the palpebral conjunctiva in HPRPG than in TG. Both groups showed equivalent improvements in TBUT, OT, and LGT values.

Conclusion

Tacrolimus 0.03% eye drops were more efficient than HPRP in increasing tear production and the number of goblet cells. However, injectable HPRP was more efficient than tacrolimus in decreasing the number of conjunctival inflammatory cells. Treatment with injectable HPRP requires an average of two to three applications, is safe and feasible, and can be used as a cheaper alternative or as an adjuvant to conventional treatment with topical immunosuppressants.

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.

Systemic Treatment of Immune-Mediated Keratoconjunctivitis Sicca with Allogeneic Stem Cells Improves the Schirmer Tear Test Score in a Canine Spontaneous Model of Disease

Keratoconjunctivitis sicca (KCS) is characterized by ocular discomfort, conjunctival hyperaemia, and corneal scarring, causing reduced aqueous tear production that can be measured using the standard Schirmer tear test (STT). Canine adipose tissue-derived MSCs (cATMSCs) have been proposed as treatment due to their anti-inflammatory effect, by releasing cytokines and immunomodulatory soluble factors.

PURPOSE

The aim of this study was to evaluate the effect of the systemic administration of cATMSCs on tear production in dogs with immune-mediated KCS, compared to classical Cyclosporine A (CsA) treatment.

METHODS

Twenty-eight client-owned dogs with spontaneous KCS were allocated in the experimental group (n = 14, treated with systemic cATMSCs or control group (n = 14, treated with CsA). SST values increased significantly at days 15 (p = 0.002), 45 (p = 0.042) and 180 (p = 0.005) with no observed side-effects in the experimental group. Eyes with an initial STT value of 11-14 mm/min maintained significant improvement at day 180, needing only artificial tears as treatment. Eyes with an initial STT value <11 mm/min needed cyclosporin treatment at day 45, so follow-up was stopped. Control animals treated with CsA did not improve their STT at day 180.

RESULTS AND CONCLUSIONS

Systemic allogeneic cATMSCs application appeared to be a feasible and effective therapy with positive outcome in dogs with initial STT between 11-14 mm/min, with a significant improvement in tear production. The STT increment was maintained for at least 180 days, without needing additional medication, thus suggesting it could constitute an alternative therapy to classical immunosuppressive treatments.

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%.

Topical Tacrolimus Progylcosomes Nano-Vesicles As a Potential Therapy for Experimental Dry Eye Syndrome

The present work aimed to evaluate the efficacy of topical tacrolimus (0.01%) loaded propylene glycol (PG) modified nano-vesicles (Proglycosomes Nano-vesicles, PNVs) for the treatment of experimental dry eye syndrome (DES) in rabbits. DES was induced by topical application of atropine (1.0%) and benzalkonium chloride (0.1%) aqueous solution. PNVs treatment (PNV group) was compared with tacrolimus solution 0.01% (TAC group) and untreated group and healthy group were used as controls. PNV treated animals showed improved clinical performance with marked increase in tear production and tear break-up time (TBUT). Further, PNVs also subside ocular inflammation as evident from absence of matrix metalloprotenaise-9 and normal ocular surface temperature (32.3 ± 0.34 °C). Additionally, PNVs have positive effect on ocular and epithelial damage observed through low ocular surface staining score and improved globlet cell density. The PNV treatment was found to more effectively compared to TAC solution and most of the parameters were close to those of healthy animals. In conclusion, tacrolimus PNV formulation (0.01%) could be a potential therapy for treatment of dry eye syndrome.

Effect of Withdrawing Chronic Topical Immune Modulating Treatment on Schirmer Tear Test Values in Dogs with Dry Eye Disease: Relevance to Dry Eye Studies

Purpose: To determine the effect of discontinuing chronic topical immune modulating (IM) treatment on Schirmer tear test (STT) values in dogs with dry eye disease (DED). Methods: Serial measurements of STTs from 14 dogs (16 eyes) previously diagnosed with DED were obtained before and after discontinuation of topical IM agents. Dogs with moderate to severe DED that had been well controlled with a topical IM treatment were included. After initial assessment topical IM treatment was discontinued, but topical lubricant was continued, and STT values were obtained sequentially. A mixed-effects regression model was used to evaluate the effects of age, gender, breed, clinical score, frequency of treatment, baseline STT value, and drug type on final STT values after IM withdrawal. P < 0.05 was considered statistically significant. Results: During the follow-up period after the IM treatment had been discontinued (136 ± 29 days), 50% of the eyes (n = 8) exhibited STT values that never decreased to <10 mm/min. In the other 50% (n = 8), STT values decreased from 15.9 ± 4.7 mm/min to 6.1 ± 0.9 mm/min. In this group, the time it took to decrease the STT to <10 mm/min was 21.1 ± 9.5 days. Severe clinical signs of DED and low baseline STT pre-IM treatment significantly affected STT post-IM treatment withdrawal (P < 0.05). Conclusions: The duration that a residual effect of topical IM treatment persists needs to be taken into consideration when studies are designed utilizing dogs with previous IM treatment for DED.

Formulation development, optimization, and in vitro assessment of thermoresponsive ophthalmic pluronic F127-chitosan in situ tacrolimus gel

To overcome problems associated with topical delivery of tacrolimus (TCS), a thermoresponsive in situ gel system containing pluronic F127 (PL), and chitosan (CS) was developed, to enhance the precorneal retention, and to sustain the release of the drug. The PL-CS in situ gel was optimized using a 2-factor-3-level central composite experimental design by selecting the concentration of PL and CS as independent variables while gelation time, gelation temperature, and spreadability as dependent variables. The optimized formulation was developed using 22.5 g PL and 0.3 g CS, gels at 33.6 °C, in 22.93 s, and showed the spreadability of 6.2 cm. In vitro studies conducted for the optimized gel revealed the sustained release of TCS (81.73% in 4 h) and improved corneal permeation (74.13% in 4 h), compared with TCS solution. The mechanism of release of TCS followed the Higuchi model with Fickian diffusion transport. Further, histopathology and HET-CAM studies revealed that the developed gel was non-irritating and safe for ocular administration.

Ocular toxicity of mustard gas: A concise review

Sulfur mustard (SM) is a chemical warfare agent that has been used throughout recent history and remains a threat today. Exposed soldiers and civilians experience a variety of symptoms primarily in the respiratory system, skin, and eyes. The ocular tissues are highly sensitive to damage by SM and undergo unique manifestations of acute, chronic, and delayed complications that can persist for months and years after exposure. The mechanisms of this unique mustard gas keratopathy are still not fully understood and animal models for the study of this disease are discussed. Recent advances in mechanisms of injury are included in this review. Ophthalmic manifestations of SM injury including persistent epithelial defects, limbal stem cell deficiency, corneal neovascularization, dry eye, and corneal opacification have been reported. A wide variety of medical and surgical therapies have been studied and are reviewed here along with potential future therapies.

Exploring Free Energy Profiles of Enantioselective Organocatalytic Aldol Reactions under Full Solvent Influence

We present a computational study on the enantioselectivity of organocatalytic proline-catalyzed aldol reactions between aldehydes in dimethylformamide (DMF). To explore the free energy surface of the reaction, we apply two-dimensional metadynamics on top of ab initio molecular dynamics (AIMD) simulations with explicit solvent description on the DFT level of theory. We avoid unwanted side reactions by utilizing our newly developed hybrid AIMD (HyAIMD) simulation scheme, which adds a simple force field to the AIMD simulation to prevent unwanted bond breaking and formation. Our condensed phase simulation results are able to nicely reproduce the experimental findings, including the main stereoisomer that is formed, and give a correct qualitative prediction of the change in syn:anti product ratio with different substituents. Furthermore, we give a microscopic explanation for the selectivity. We show that both the explicit description of the solvent and the inclusion of entropic effects are vital to a good outcome-metadynamics simulations in vacuum and static nudged elastic band (NEB) calculations yield significantly worse predictions when compared to the experiment. The approach described here can be applied to a plethora of other enantioselective or organocatalytic reactions, enabling us to tune the catalyst or determine the solvent with the highest stereoselectivity.

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 features of cats with aqueous tear deficiency: a retrospective case series of 10 patients (17 eyes)

OBJECTIVES

The aim of this study was to describe the clinical findings, diagnostic test results and response to therapy of cats with Schirmer tear test 1 (STT-1) values below the reference interval.

METHODS

The medical records of three institutions were searched for cats with ocular surface disease and STT-1 values <9 mm/min, confirmed at two or more separate visits.

RESULTS

Ten cats (17 eyes) were included. The mean ± SD (range) age and STT-1 values in affected eye(s) were 6.1 ± 5.7 (0.2-16) years and 2.4 ± 3.1 (0-8) mm/min, respectively. Concurrent ocular surface disease was bilateral in 5/10 cats. Clinical signs included conjunctivitis (14/17 eyes), corneal ulceration (6/17 eyes), non-ulcerative keratitis (4/17 eyes), symblepharon (4/17 eyes), eosinophilic keratitis (3/17 eyes), corneal sequestrum (3/17 eyes), corneal fibrosis (2/17 eyes) and meibomitis (2/17 eyes). Management included: topically applied lacrimomimetics, antiviral drugs, corticosteroids or immunomodulatory drugs; orally administered famciclovir; or surgical procedures, in various combinations. Response to therapy (defined as an increase in STT-1 value of ⩾5 mm/min) was transient (seen at a single reassessment) in 65% of eyes and sustained (seen at ⩾2 consecutive reassessments) in 18% of eyes.

CONCLUSIONS AND RELEVANCE

Clinical features seen in cats with low STT-1 values are described, although the association between aqueous deficiency and the reported ocular changes is unknown at this time. We encourage clinicians to assess the tear film in cats with ocular surface disease, and initiate therapy with lacrimomimetics if STT-1 values are repeatedly below normal. Such information will further define aqueous tear deficiency in cats, providing a better understanding of disease prevalence, pathogenesis and treatment.

Reduction in the inflammatory markers CD4, IL-1, IL-6 and TNFα in dogs with keratoconjunctivitis sicca treated topically with mesenchymal stem cells

Keratoconjunctivitis sicca (KCS) is of predominantly immune-mediated origin. Dogs are an excellent model for understanding this disease, as the origin of KCS in dogs is like that in humans. The objective of this study was to localize and quantify immunological markers, such as CD4 lymphocytes, interleukin (IL)-1, IL-6 and tumor necrosis factor alpha (TNFα), before and after topical treatment with mesenchymal stem cells (MSCs). Twenty-two dogs positive for KCS were topically treated with 50 μL (1 × 10⁶ MSCs) in the conjunctival sac and were evaluated for 6 months. The levels of the markers CD4, IL-6, IL-1 and TNFα were analyzed in conjunctival biopsy and cytology of the third eyelid gland by immunohistochemistry and immunocytochemistry. The results showed that before treatment, there was marked expression of all the markers (CD4, IL-6, IL-1 and TNFα), and after 6 months, there were significant (p < .05) reductions in the expression levels of all the markers. These results demonstrated that topical MSC treatment promotes a significant decrease in the expression levels of these inflammatory markers and could be used as adjuvant therapy in the treatment of KCS in dogs and humans. In addition, these markers can be excellent tools for diagnosing and analyzing the progression of KCS.

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.

Comparison of 0.025% FK-506, 0.05% Cyclosporin A, and 0.3% Sodium Hyaluronate Eye Drops for the Treatment of Botulinum Toxin B-Induced Mouse Dry Eye

PURPOSE

To compare the effects of FK-506, cyclosporin A (CsA), and sodium hyaluronate (HA) eye drops for the treatment of botulinum toxin B (BTX-B)-induced mouse dry eye.

METHODS

CBA/J mice were randomized into 5 groups. The groups received treatment with eye drops containing 0.025% FK-506 combined with 0.3% HA (FK-506+HA group), 0.025% FK-506 (FK-506 group), 0.05% CsA (CsA group), 0.3% HA (HA group), or 0.9% saline (saline group) 3 days after an intralacrimal gland injection with 20 mU of BTX-B. Tear production, corneal fluorescein staining, blink rate, and the mRNA and protein expression levels of inflammatory cytokines were measured.

RESULTS

FK-506+HA eye drops increased tear production and reduced the corneal fluorescein staining scores at all time points after treatment compared with those in the saline group. Compared with those in the saline group, the tear production and severity of corneal epithelial defects in the FK-506 group were significantly improved at weeks 2 and 4. Compared with the saline eye drops, the CsA eye drops ameliorated only tear production and corneal fluorescein staining scores at week 4 after administration. The FK-506+HA, FK-506, and CsA eye drops downregulated the expression of inflammatory cytokines in both the keratoconjunctival tissues and lacrimal glands at week 4.

CONCLUSIONS

The topical application of 0.025% FK-506 combined with 0.3% HA, 0.025% FK-506, or 0.05% CsA can suppress the expression of inflammatory cytokines and can alleviate the signs of dry eye. Topical application of 0.025% FK-506 combined with 0.3% HA showed the best therapeutic effect and may be a possible therapy for dry eye.

Eficácia dos colírios ciclosporina e tacrolimo no tratamento de ceratoconjuntivite seca em cães

RESUMO O objetivo deste estudo foi avaliar os efeitos do tacrolimo e da ciclosporina na produção lacrimal de cães com ceratoconjuntivite seca (CCS) durante 90 dias. Para tanto, foram utilizados colírios de tacrolimo 0,02% (TcL) e ciclosporina 0,1% (CsA) em 14 cães com CCS. Os animais foram distribuídos em dois grupos e avaliados antes do início do tratamento (T0) e aos 15 (T1), 30 (T2), 45 (T3), 60 (T4), 75 (T5) e 90 (T6) dias após o início do tratamento. Na avaliação clínica, observou-se maior redução da secreção ocular, da opacidade e do edema corneano e da vascularização conjuntival. no grupo tacrolimo. No teste de Schirmer, verificou-se produção basal de 6(4,07 e 5,86(2,85mm/min no TcL e CsA, respectivamente, com aumento significativo da produção lacrimal em ambos os grupos, contudo houve aumento significativo da produção lacrimal a partir dos 15 dias de tratamento no grupo TcL (17,88(5,51mm/min), mas apenas a partir dos 45 dias no grupo CsA (11,86(4,74mm/min). Conclui-se que o uso do colírio tacrolimo aumentou em 68,83% a produção lacrimal em 90 dias de tratamento, comparado com a ciclosporina (56,82%), além de diminuir as manifestações clínicas inerentes à CCS, quando comparado à terapia com ciclosporina.

Efficacy of HL036 versus Cyclosporine A in the Treatment of Naturally Occurring Canine Keratoconjunctivitis Sicca

PURPOSES

To (i) evaluate the efficacy and safety of HL036, a tumor-necrosis factor (TNF)-α-blocking protein, in the treatment of naturally occurring canine keratoconjunctivitis sicca (KCS) and (ii) compare these features with those of 1% cyclosporine A (CsA).

MATERIALS AND METHODS

Dogs (n = 29) diagnosed with KCS were randomly assigned to receive one drop topical aqueous HL036 (0.2, 1, or 5 mg/mL) or 1% CsA in the affected eye(s) at 12-h intervals for 42 days. Schirmer's tear test (STT), fluorescein corneal staining (FCS), and clinical-sign scores were evaluated prior to application (day-0) and on days 14, 28, and 42 post-treatment. Of the 29 dogs enrolled, 19 (65.5%) received HL036 (HL036 group) and 10 (34.5%) received 1% CsA (CsA group). A linear mixed-effects model analysis was performed to determine score differences between groups and over time.

RESULTS

After treatment, clinical-sign scores and STT values had significantly improved compared with baseline levels in dogs of both treatment groups. Decreases in total clinical-sign scores for the HL036-group were greater than those of 1% CsA group. No severe adverse reactions were noted in either group.

CONCLUSIONS

Our findings suggest that topical aqueous HL036 is well-tolerated and more effective than 1% CsA for treating naturally occurring canine KCS.

Canine Diabetes Mellitus Associated Ocular Disease

Diabetes mellitus (DM) is a commonly encountered disease in companion animal veterinary practice. Ocular complications in dogs with DM are thought to be common but there are no reports of the overall incidence of DM-associated ocular disease. Some complications, such as cataracts and ocular surface disease, can lead to vision loss and significant morbidity among DM patients, therefore early recognition and intervention are essential for successful outcomes. The purpose of this article is to provide a review of several currently known or suspected ocular diseases associated with DM.

Immune Relevant Models for Ocular Inflammatory Diseases

Ocular inflammatory diseases, such as dry eye and uveitis, are common, painful, difficult to treat, and may result in vision loss or blindness. Ocular side effects from the use of antiinflammatory drugs (such as corticosteroids or nonsteroidal antiinflammatories) to treat ocular inflammation have prompted development of more specific and safer medications to treat inflammatory and immune-mediated diseases of the eye. To assess the efficacy and safety of these new therapeutics, appropriate immune-relevant animal models of ocular inflammation are needed. Both induced and naturally-occurring models have been described, but the most valuable for translating treatments to the human eye are the animal models of spontaneous, immunologic ocular disease, such as those with dry eye or uveitis. The purpose of this review is to describe common immune-relevant models of dry eye and uveitis with an overview of the immuno-pathogenesis of each disease and reported evaluation of models from small to large animals. We will also review a selected group of naturally-occurring large animal models, equine uveitis and canine dry eye, that have promise to translate into a better understanding and treatment of clinical immune-relevant ocular disease in man.

Immunohistochemical evaluation of lymphocyte populations in the nictitans glands of normal dogs and dogs with keratoconjunctivitis sicca

Idiopathic canine keratoconjunctivitis sicca (iKCS) is a common condition of the canine eye involving a deficiency in aqueous tear production which is commonly held to have an immune-mediated, as most probably an autoimmune aetiopathogenesis. Yet to date no direct evaluation has been made of the inflammatory cell populations in the lacrimal tissue of dogs with iKCS. Here we sought to quantify T and B lymphocyte populations in the lacrimal tissue of the nictitans glands of dogs with iKCS those with neurological KCS (nKCS)and also in dogs with tear production within the recognized normal levels and no ocular surface signs of KCS. Nictitans glands were obtained from 10 healthy dogs with no signs or history consistent with KCS at post-mortem or after enucleation. Nictitans glands were also obtained at parotid duct transposition surgery from ten dogs with idiopathic KCS and three with neurogenic KCS. Histological sections form the lacrimal tissue were processed immunohistochemically with primary monoclonal antibodies recognizing the T lymphocyte CD3 antigen and the B lymphocyte CD79a antigen. Cell numbers were counted in 10 randomly sampled representative high-power fields in five sections. Statistical significance of differences in cell numbers was determined using analysis of variance with significance achieved at p=0.05.Nictitans glands from dogs with iKCS showed elevated numbers of T and B lymphocytes compared with those from dogs with normal tear production. The increase in the T cell population was highly statistically significant (p=0.0025) while the increase in B cells, while statistically significant was less pronouncedly so (p=0.049). T and B lymphocyte numbers were not significantly elevated in nictitans glands from dogs with neurogenic KCS compared with those in dogs with normal tear production. The elevation in the T cell population seen in dogs with idiopathic KCS strongly supports the widely held assumption that this disease is an immune-mediated and probably autoimmune. The lack of increase in T cell populations in dogs with nKCS strongly suggests that the changes in iKCS are causing the tear deficiency and not resulting from it.

Use of clinical vignette questionnaires to investigate the variation in management of keratoconjunctivitis sicca and acute glaucoma in dogs

There is little peer-reviewed research assessing therapeutic effectiveness in canine eye disease. Current treatments used in first opinion and ophthalmology referral practices are also somewhat poorly documented. The aim of this study was to investigate the current management of canine keratoconjunctivitis sicca (KCS) and acute primary angle-closure glaucoma (PACG) by veterinary surgeons. Questionnaires using clinical vignettes were administered to a cross section of general practitioners ('GPs') and veterinarians engaged in or training for postgraduate ophthalmology practice ('PGs'). Similar treatment recommendations for KCS (topical cyclosporine, lubricant, antibiotic) were given by both groups of veterinarians with the single exception of increased topical antibiotic use by GPs. Treatment of acute glaucoma diverged between groups: PGs were much more likely to recommend topical prostaglandin analogues and a wider array of both topical and systemic treatments were recommended by both groups. Systemic ocular hypotensive agents were suggested infrequently. Our results suggest that treatments may vary substantially in ocular conditions, particularly in conditions for which neither guidelines nor high-quality evidence exists. This study highlights the need for novel strategies to address evidence gaps in veterinary medicine, as well as for better evaluation and dissemination of current treatment experience.

Comparison between fish and linseed oils administered orally for the treatment of experimentally induced keratoconjunctivitis sicca in rabbits

The objective of this study was to compare the efficacy of two sources of omega 3 and 6, fish oil (FO) and linseed oil (LO), orally administered, alone or in combination, for treating experimentally induced keratoconjunctivitis sicca (KCS) in rabbits. Twenty-eight New Zealand rabbits were used in this study. Seven animals were allocated to the C group (negative control), and KCS was induced in 21 animals by topically applying 1% atropine sulfate drops for 7 days. Treatment with atropine was maintained throughout the study period (12 weeks). The rabbits were divided into 3 treatment groups containing 7 animals each: FO group, LO group and FLO group (FO and LO). The animals were evaluated using the Schirmer Tear Test I (STT I), Rose Bengal Test (RBT), fluorescein test (FT), tear film break-up time (TBUT), and conjunctival and histopathological analysis. There was a significant increase in STT I and TBUT values in treatment groups, but the increase occurred earlier in the FO group. The results of the RBT and FT were similar among treatment groups, except FT, in the FLO group, negative staining was only in 12 weeks. There was a significant decrease in the number of goblet cells in the FLO group compared with the other groups. The results demonstrated that orally administered of FO and LO improved the clinical signs of KCS. However, improvement occurred earlier in the FO group. Using oils in combination did not provide additional benefits. These results contribute to the future development of new oral formulations as adjuvant therapies for KCS.

Surgical and medical treatment of ocular disease in a dog with Ehlers-Danlos syndrome

Correctional surgery was performed on a 3‐year‐old intact male shih tzu presenting with Ehlers–Danlos syndrome, ocular disease, and skin fold dermatitis. A one‐year follow‐up showed that no further clinical corrections were needed. Therefore, surgery could be considered in some canine patients with Ehlers–Danlos syndrome.

Clinical evaluation of a nutraceutical diet as an adjuvant to pharmacological treatment in dogs affected by Keratoconjunctivitis sicca

Background

Canine keratoconjunctivitis sicca (cKCS) is an inflammatory eye condition related to a deficiency in the tear aqueous fraction. Etiopathogenesis of such disease is substantially multifactorial, combining the individual genetic background with environmental factors that contribute to the process of immunological tolerance disruption and, as a consequence, to the emergence of autoimmunity disease. In this occurrence, it is of relevance the role of the physiological immune-dysregulation that results in immune-mediated processes at the basis of cKCS. Current therapies for this ocular disease rely on immunosuppressive treatments. Clinical response to treatment frequently varies from poor to good, depending on the clinical-pathological status of eyes at diagnosis and on individual response to therapy. In the light of the variability of clinical response to therapies, we evaluated the use of an anti-inflammatory/antioxidant nutraceutical diet with potential immune-modulating activity as a therapeutical adjuvant in cKCS pharmacological treatment. Such combination was administered to a cohort of dogs affected by cKCS in which the only immunosuppressive treatment resulted poorly responsive or ineffective in controlling the ocular symptoms.

Results

Fifty dogs of different breeds affected by immune-mediated cKSC were equally distributed and randomly assigned to receive either a standard diet (control, n = 25) or the nutraceutical diet (treatment group, n = 25) both combined with standard immunosuppressive therapy over a 60 days period. An overall significant improvement of all clinical parameters (tear production, conjunctival inflammation, corneal keratinization, corneal pigment density and mucus discharge) and the lack of food-related adverse reactions were observed in the treatment group (p < 0.0001).

Conclusions

Our results showed that the association of traditional immune-suppressive therapy with the antioxidant/anti-inflammatory properties of the nutraceutical diet resulted in a significant amelioration of clinical signs and symptoms in cKSC. The beneficial effects, likely due to the presence of supplemented nutraceuticals in the diet, appeared to specifically reduce the immune-mediated ocular symptoms in those cKCS-affected dogs that were poorly responsive or unresponsive to classical immunosuppressive drugs. These data suggest that metabolic changes could affect the immune response orchestration in a model of immune-mediated ocular disease, as represented by cKSC.

Preformulation Studies of a Liposomal Formulation Containing Sirolimus for the Treatment of Dry Eye Disease

PURPOSE

The aim of this study was to develop and characterize a liposomal product containing sirolimus to be administered subconjunctivally for the treatment of nonresponsive keratoconjunctivitis sicca (KCS) or dry eye.

METHODS

Formulations were prepared using an ethanol injection method and an adaptation of the heating method in pursuance of the most suitable methodology for future industrial production. Liposomes were loaded with either a high dose of 1 mg/mL of sirolimus or a less toxic dose of 0.4 mg/mL. The effects of critical process and formulation parameters were investigated. Liposomes were characterized in terms of size, zeta potential, polydispersity, differential scanning calorimetry, morphology, entrapment efficiency, phospholipid content, thermal stability, and sterility. The formulation was evaluated clinically in dogs with spontaneous KCS.

RESULTS

Sterile liposomal dispersions with sizes ranging from 140 to 211 nm, were successfully obtained. High entrapment efficiency of 93%-98% was achieved. The heating method allowed an easier production of liposomes with high entrapment efficiency, to significantly shorten production time and the elimination of the use of alcohol. The poor stability of the obtained liposomes in aqueous dispersion made the inclusion of a lyophilization step necessary to the manufacturing process. In vivo testing of the liposomal sirolimus formulations in the spontaneous KCS dog model have produced promising results, particularly with a sirolimus dose of 1 mg/mL, indicating the need for further development and study of proposed formulations in the treatment of canine KCS. Clinical improvement in tear production in dogs with spontaneous KCS treated with the 1 mg/mL dose product was observed.

CONCLUSIONS

The heating method allowed easier production of high entrapment efficiency liposomes to significantly shorten production time and the elimination of the use of alcohol. Tear production was increased in dogs administered with the formulation.

Immune-mediated keratoconjunctivitis sicca in dogs: current perspectives on management

Keratoconjunctivitis sicca (KCS) is a frequent canine ophthalmic disease, resulting from the deficiency of one or more elements in the precorneal tear film. There are different known causes of KCS in dogs, including congenital, metabolic, infectious, drug induced, neurogenic, radiation, iatrogenic, idiopathic, and immune mediated, though the last one is the most prevalent form in dogs. Initially, clinical signs of KCS include blepharospasm caused by ocular pain, mucoid to mucopurulent ocular discharge, and conjunctival hyperemia; secondary bacterial infection may also occur, with chronicity, corneal epithelial hyperplasia, pigmentation, neovascularization, and corneal ulceration. The diagnosis of KCS is based on the presence of consistent clinical signs and measurement of decreased aqueous tear production using the Schirmer tear test. Therapy is based on administering the following topical drugs: ocular lubricant, mucolytics, antibiotics, corticosteroids, pilocarpine, and immunomodulators. These last drugs (eg, cyclosporine, pimecrolimus, and tacrolimus) have immunosuppressive activity and stimulate tear production. Furthermore, the nerve growth factor is a new subject matter of the research. Although these therapies are advantageous, stimulation of natural tear production seems to provide the highest recovery in clinical signs and prevention of vision loss. The goal of the following article is to describe the recent developments about KCS in dogs emphasizing the use of new therapies.

Effect of once daily topical 0.3% naltrexone on tear parameters and corneal sensitivity in dogs with uncontrolled keratoconjunctivitis sicca: a double-masked randomized placebo-controlled clinical trial

OBJECTIVE

To determine the effect of once daily topical 0.3% naltrexone (NTX) on tear production, tear film breakup time (TFBUT), and corneal sensitivity in dogs with uncontrolled keratoconjunctivitis sicca (KCS).

ANIMALS STUDIED

Sixteen dogs with uncontrolled KCS.

PROCEDURES

A randomized placebo-controlled trial was performed in 16 dogs with topical 0.3% NTX once daily or topical saline solution drops once daily. A baseline was obtained at week 0 for tear production (Schirmer tear test 1 and 2-STT1, STT2), TFBUT, and corneal sensitivity. STT1, STT2, and TFBUT were then subsequently measured at weeks 1, 2, and 4 while on NTX or saline drops. Corneal sensitivity measures were repeated at week 4. The drops were subsequently discontinued and all parameters rechecked at week 5.

RESULTS

There was no statistically significant difference in tear parameters or corneal sensitivity between the NTX-treated and the saline-treated groups.

CONCLUSION

Topical 0.3% NTX given as a once daily dose over 4 weeks did not alter tear production, tear film stability, or corneal sensitivity in dogs with uncontrolled KCS.

Comparação entre dois protocolos de tratamento de ceratoconjuntivite seca experimentalmente induzida em coelhos

O objetivo deste estudo foi avaliar e comparar a eficácia de dois protocolos de tratamento de ceratoconjuntivite seca (CCS) experimentalmente induzida em coelhos: uma formulação oftálmica tópica composta por álcool polivinílico 1,4%, adicionado com acetilcisteína 10% e pilocarpina 1% (AAP), e outro protocolo com o uso do óleo de semente de linhaça (OL) tópico em forma de colírio, durante 12 semanas. Foram utilizados 15 coelhos machos, adultos, da raça Nova Zelândia, alocados aleatoriamente em três grupos: grupo C (controle), grupo AAP (formulação oftálmica) e grupo L (OL tópica). Os animais foram avaliados semanalmente pelo teste lacrimal de Schirmer, teste de fluoresceína e teste de Rosa Bengala; uma vez por mês, pelo exame de citologia esfoliativa ocular; ao final do experimento, pela análise histopatológica da córnea e conjuntiva. Os resultados demonstraram que houve um aumento maior na produção lacrimal quando utilizada a formulação oftálmica, e uma resolução mais rápida das úlceras de córnea, bem como diminuição no número de células desvitalizadas quando utilizado o óleo de semente de linhaça, além de aumento no número de células caliciformes em ambos os grupos de tratamento. A associação desses dois protocolos pode ser no futuro uma alternativa no tratamento da CCS.

Liposomes containing bile salts as novel ocular delivery systems for tacrolimus (FK506): in vitro characterization and improved corneal permeation

The objective of this study was to investigate the potential of liposomes containing bile salts as an ophthalmic delivery system for tacrolimus to improve corneal permeability. Liposomes containing bile salts, including sodium taurocholate, sodium deoxycholate, and sodium glycocholate, were produced by the thin-film dispersion method with a particle size of approximately 100 nm and an entrapment efficiency of more than 90%. Less than 5% tacrolimus was released from conventional liposomes and from liposomes containing sodium taurocholate, sodium deoxycholate, or sodium glycocholate over 12 hours. The cellular uptake of conventional liposomes was significantly higher than that of liposomes containing bile salts. However, liposomes containing bile salts exerted a 3–4-fold increase of tacrolimus in ex vivo corneal transport of tacrolimus compared with conventional liposomes. When rabbit eyes were treated with a DiI perchlorate-loaded liposome suspension, liposomes containing bile salts showed fast and sustained penetration across the cornea. Unfortunately, liposomes containing sodium deoxycholate caused toxicity or irritation to both spontaneously derived human corneal epithelial cells and the rabbit cornea. Therefore, liposomes containing sodium taurocholate and sodium glycocholate are potential carriers in ocular drug delivery systems, given their low toxicity and vastly improved permeability.

Partial ligation of the transposed parotid duct at the level of the parotid gland for excessive salivary secretions

OBJECTIVE

To determine the outcome and effect of a partial ligation of the transposed parotid duct at the level of the parotid gland in four dogs with excessive salivation and ocular irritation.

METHODS

Four dogs were previously diagnosed with absolute keratoconjunctivitis sicca. After a parotid duct transposition (PDT) surgery, these dogs experienced excessive saliva production and abundant salivary precipitates, which resulted in epiphora, moist dermatitis, blepharospasm, and keratitis. In an effort to decrease saliva production, a partial ligation of the transposed duct at the level of the parotid gland was performed. Two or three accessory branches to the primary parotid duct were ligated at the level of the salivary gland.

RESULTS

The four cases were three Yorkshire terriers and a Chihuahua. The average age of the four patients was 2.5 years. Partial ligation of accessory branches of the parotid duct at the level of the parotid gland after a PDT in this study demonstrated improved ocular comfort, decreased salivary precipitates, and adequate Schirmer tear test results without marked epiphora in three of the four animals. The male Yorkshire had epiphora after the initial partial ligations of two accessory branches were placed at the level of the parotid gland. To correct the excessive salivary flow, two additional ligatures were placed at a later date, which resolved the epiphora.

CONCLUSION

Partial ligation of the parotid duct at the level of the parotid gland proved to be an effective technique in moderating the salivation in these four patients with excessive salivary secretions after PDT.

Parotid duct transposition in dogs: a retrospective review of 92 eyes from 1999 to 2009

OBJECTIVE

  The aim of this study was to perform a retrospective review of parotid duct transposition (PDT) in the dog to determine the rate and nature of complications, the success and failure rates and to evaluate owner satisfaction.

METHODS

  Medical records of 56 dogs (92 eyes) that underwent PDT and subsequent follow-up by a veterinary ophthalmologist were reviewed. Forty owners (40 dogs/66 eyes) were contacted by telephone and 37 owners (37 dogs/60 eyes) also completed a visual analog scale questionnaire. Statistical evaluation included Wilcoxon Signed Rank tests, one-way analysis of variance and Kaplan-Meier survival analysis with Wilcoxon and Log-rank tests.

RESULTS

  The mean follow-up was 38.7 months (range 1-109 months). The surgical success rate was 92% (85/92 eyes). Total failures (8%, 7/92 eyes) were because of severe saliva intolerance (n = 5 eyes) and PDT failure (n = 2 eyes). The complication rate was 50% (46/92 eyes) of which 61% (28/46 eyes) were managed medically and 39% (18/46 eyes) required further surgery. Ninety percent (36/40) of owners indicated that they would proceed with surgery again. Statistically significant improvements in owner perception of ocular comfort, number of daily topical treatments, ocular wetness, and postoperative vision were identified.

CONCLUSIONS

  This study shows that PDT is a successful procedure based on clinical findings and in terms of owner perception. It has also demonstrated that PDT improves ocular comfort and vision in medically refractive cases of keratoconjunctivitis sicca, and that a low level of on-going management is required in 33% of cases.

An investigation comparing the efficacy of topical ocular application of tacrolimus and cyclosporine in dogs

The purpose of this paper was to determine the efficacy and safety of topical tacrolimus, compared to cyclosporine, for treating keratoconjunctivitis sicca (KCS) in dogs. This study was a two-phase, randomized, controlled, masked clinical trial. Phase 1 evaluated ophthalmic 0.03% tacrolimus in normal dogs. Ocular examinations were performed daily. Phase 2 evaluated the efficacy of tacrolimus in treating KCS. Half the dogs received 2% cyclosporine A; the others received 0.03% tacrolimus, both diluted in olive oil. Four ophthalmic examinations were done over 12 weeks. There was no significant difference between groups in phase I. In phase 2, there was no significant difference in Schirmer tear test I (STT) results between the two groups, and both groups had a significant increase in STT over time. Both drugs were effective in increasing the STT in dogs naïve to lacrimostimulants. Tacrolimus was effective in increasing the STT in 4 dogs currently nonresponsive to cyclosporine.

Efficacy of topically applied liposome-bound tetracycline in the treatment of dry eye model

OBJECTIVE

To evaluate the effects of liposome-bound tetracycline eye drops in a rabbit dry eye model evaluating their advantage of being less allergic, preservative free and prolonged action compared with other tear substitutes.

PROCEDURES

New Zealand albino rabbits were equally divided into control group and dry eye induced groups. Dryness was induced in 24 eyes of 12 healthy adult male albino rabbits by instilling atropine sulfate eye drops 1% three times daily for 1 week, then animals were subdivided into four groups; group 1 (rabbits with dry eye model), groups 2, 3, and 4: rabbits with dry eye model treated for 7 days starting on 7th day of dryness induction with either tetracycline, empty liposome, or combined tetracycline with liposome as topical eye drops respectively. Schirmer (STT) test and tear break up time (TBUT) were assessed on days 0, 2, 4, 7, 9, 11, and 14. Animals were sacrificed on day 14 and histopathological examination of the cornea and conjunctiva was performed.

RESULTS

Tear break up time and STT test values were significantly improved in groups 2, 3, 4 as compared with group 1. The histopathological examination showed normal cytoarchitecture of corneas and conjunctivae in groups 2, 3, 4 against the dryness effect that continued to affect the cornea and conjunctival epithelium in group 1. There was a significant improvement in the group treated with liposome-bound tetracycline eye drops (group 4) as compared with tetracycline alone (group 2) and empty liposome (group 3).

CONCLUSION

The use of liposome encapsulated tetracycline significantly improved STT and TBUT values as well as reverse surface ocular pathology.

Autoimmunity at the ocular surface: pathogenesis and regulation

A healthy ocular surface environment is essential to preserve visual function, and as such the eye has evolved a complex network of mechanisms to maintain homeostasis. Fundamental to the health of the ocular surface is the immune system, designed to respond rapidly to environmental and microbial insults, whereas maintaining tolerance to self-antigens and commensal microbes. To this end, activation of the innate and adaptive immune response is tightly regulated to limit bystander tissue damage. However, aberrant activation of the immune system can result in autoimmunity to self-antigens localized to the ocular surface and associated tissues. Environmental, microbial and endogenous stress, antigen localization, and genetic factors provide the triggers underlying the immunological events that shape the outcome of the diverse spectrum of autoimmune-based ocular surface disorders.

Visual loss associated with tacrolimus: case report and review of the literature

Tacrolimus is an immunosuppressive medication in the class of calcineurin inhibitors that acts by inhibiting T-cell and interleukin-2 activity, and is commonly used after allogeneic organ transplant. We present a patient who used tacrolimus after cadaveric kidney transplant and experienced blurry vision. Ocular examination and patient's course subsequently revealed aqueous tear deficiency as a dose-dependent adverse effect of oral tacrolimus.