Ocular manifestations of liver disease: an important diagnostic aid.

PURPOSE: This review examined existing literature to determine various ocular manifestations of liver pathologies, with a focus on metabolic deficiencies as well as viral and immune liver conditions. METHODS: Recent data were compiled from PubMed from 2000 to 2020 using keywords that were relevant to the assessed pathologies. Ocular presentations of several liver pathologies were researched and then summarized in a comprehensive form. RESULTS: Several ocular manifestations of liver disease were related to vitamin A deficiency, as liver disease is associated with impaired vitamin A homeostasis. Alcoholic liver cirrhosis can result in vitamin A deficiency, presenting with Bitot spots, xerosis, and corneal necrosis. Congenital liver diseases such as mucopolysaccharidoses and peroxisomal disorders are also linked with ocular signs. Viral causes of liver disease have associations with conditions like retinal vasculitis, keratoconjunctivitis sicca, retinopathies, Mooren's ulcer, and Sjogren's syndrome. Autoimmune hepatitis has been linked to peripheral ulcerative keratitis and uveitis. CONCLUSIONS: Building strong associations between ocular and liver pathology will allow for early detection of such conditions, leading to the early implementation of management strategies. While this review outlines several of the existing connections between hepatic and ophthalmic disease, further research is needed in the area in order to strengthen these associations.

Ocular manifestations of rheumatoid arthritis.

PURPOSE OF REVIEW: This article summarizes the pathophysiology of rheumatoid arthritis and common ocular manifestations that it is associated with: keratoconjunctivitis sicca, episcleritis, scleritis, and peripheral ulcerative keratitis. RECENT FINDINGS: Newer biologic agents are being used to effectively treat rheumatoid arthritis and its ocular manifestations. SUMMARY: The eye is a frequent extra-articular site of inflammation in patients with rheumatoid arthritis. Ocular involvement can range from more benign conditions such as keratoconjunctivitis sicca and episcleritis, to potentially vision and globe-threatening diseases like scleritis and peripheral ulcerative keratitis. Clinicians should be aware of these ophthalmic manifestations and the various treatment options that are available. Coordination between ophthalmology and rheumatology is helpful in the treatment of these patients.

Phenotypic features and predictors of the clinical severity of keratoconjunctivitis sicca and salivary gland dysfunction in patients with Sjögren's syndrome: a longitudinal analysis of the Korean Initiative of primary Sjögren's Syndrome (KISS) cohort.

OBJECTIVE: The aim was to investigate prevalence and degree of ocular and oral involvement in patients with primary Sjögren's syndrome (PSS). METHOD: We analysed 134 participants from the Korean Initiative of PSS cohort who completed a 2 year follow-up oral and ocular sign test. The severity of keratoconjunctivitis sicca (KCS) was determined with the Schirmer I test value (STV) [abnormal (AB) ≤ 5 mm/5 min; normal (N) > 5 mm/5 min]. Salivary gland dysfunction (SGD) was determined by unstimulated whole salivary (UWS) flow rate [moderate to severe (MS) < 0.1 mL/min; mild (Mi) ≥ 0.1 mL/min]. Subgroups were divided into three groups according to STV and severity of SGD: AB-STV/MS-SGD, AB-STV/Mi-SGD, and N-STV/MS-SGD groups. We analysed the changes in STV and SGD during the follow-up period. RESULTS: Among the 134 participants enrolled in this study, 105 (78%) were placed in the AB-STV/MS-SGD group, 16 (12%) in the AB-STV/Mi-SGD, and 13 (10%) in the N-STV/MS-SGD at the 2 year follow-up. The AB-STV/Mi-SGD group was younger than the other two groups, and had a lower Xerostomia Inventory score and lower level of ß2-microglobulin. Participants in the N-STV/MS-SGD group had less hyperimmunoglobulinaemia, rheumatoid factor (RF), and antinuclear antibodies (ANAs). Patients and those with positive RF or ANA ≥ 1:320 at baseline were more likely to have abnormal STV at the 2 year follow-up. CONCLUSIONS: Patients with PSS and positive RF or ANA ≥ 1:320 at baseline may benefit from regular ophthalmology examinations, even if they do not have KCS at baseline or dry eye symptoms.

Rheumatoid factor isotype and Ro epitope distribution in primary Sjögren syndrome and rheumatoid arthritis with keratoconjunctivitis sicca.

Primary Sjögren syndrome (pS) is associated with autoantibodies such as rheumatoid factor (RF) and anti-nuclear antibodies such as anti-Ro (SS-A) and/or La (SS-B). Recent developments within autoimmune diagnostics allow quantitation of RF subclasses and anti-Ro epitopes. Will this refinement by autoimmune diagnostics help predicting development of extraglandular manifestations (EGM) in pS patients? A cohort of pS and rheumatoid arthritis (RA) patients with keratoconjunctivitis sicca (n = 35 and 16, resp) was included. Of the pS patients, 54% developed one or more EGM. Antibodies quantitated were IgM-RF, IgA-RF, IgG-RF, anti-Ro52, and anti-Ro60. Upon analysis of RF isotypes, pS patients generally displayed higher IgA-RF concentrations than RA patients (126 versus 49 U/ml, p = 0.015), while the dominant RF isotype in RA patients was IgM-RF (82.5 versus 38 U/ml, p = 0.012). No differences were observed regarding IgG-RF concentrations. In pS without/with EGM, the median RF IgM concentrations were similar, while RF IgA and IgG concentrations tended to be lower in pS patients with EGM > 1. Both Ro epitopes were strongly recognized by almost all pS patients, independent from EGM, while these antibodies were absent in RA patients. Primary Sjögren syndrome and RA patients have distinct serological profiles when analysing RF and Ro-specific antibodies. A longitudinal study of switched RF isotypes in pS patients is worthwhile from an immunological point of view, but its value is limited regarding identification of pS patients prone to developing EGM or RA patients prone to developing secondary sicca symptoms.

Severity of Sjögren's Syndrome Keratoconjunctivitis Sicca Increases with Increased Percentage of Conjunctival Antigen-Presenting Cells.

This study investigated the relationship between clinical severity and percentage of conjunctival antigen-presenting cells (APCs) in Sjögren's syndrome (SS)-associated keratoconjunctivitis sicca (KCS). KCS clinical severity was based on symptom severity, tear volume, tear break-up time, and ocular surface dye staining. Conjunctival goblet cell density (GCD) was measured in periodic acid Schiff (PAS)-stained membranes. Conjunctival cells obtained by impression cytology were used for flow cytometry to measure percentages of CD45⁺HLA-DR⁺ APCs and mature CD11c⁺CD86⁺ dendritic cells (DCs). Compared to normal conjunctiva, the percentages of HLA-DR⁺ and CD11c⁺CD86⁺ cells were higher in the conjunctiva of the KCS group (p < 0.05). The percentage of CD45⁺HLA-DR⁺ cells positively correlated with clinical severity (r = 0.71, p < 0.05) and negatively correlated with GCD (r = -0.61, p < 0.05). Clinical severity also negatively correlated with GCD (r = -0.54, p < 0.05). These findings indicate that a higher percentage of APCs and mature DCs in the conjunctiva is associated with more severe KCS in SS. These APCs may contribute to the generation of the pathogenic Th1 cells that cause goblet cell loss in KCS.

A Review of Ocular Graft-Versus-Host Disease.

: Graft-versus-host disease (GVHD) is a major complication that occurs following allogeneic hematopoietic stem cell transplantation, which is a potential curative therapy used in a variety of malignant or benign hematological diseases. Graft-versus-host disease primarily occurs in many organs, but most notably in the skin, lungs, gastrointestinal tract, liver, eyes, mucosa, and musculoskeletal system. Ocular manifestations of GVHD may precede other systemic GVHD findings, and it may be a poor prognosis for mortality. While all parts of the eye may be affected, ocular GVHD occurs primarily in the ocular surface. Dry eye disease or keratoconjunctivitis sicca is the most common presenting manifestation of chronic ocular GVHD. Dry eye disease in ocular GVHD is a multifactorial process, which involves destruction and fibrosis of lacrimal glands and conjunctiva, leading to tear film deficiency and instability. Depending on the severity of ocular involvement and response to treatment, ocular GVHD may cause decreased quality of life. Management of GVHD begins with prevention by understanding risk factors and by implementing prophylactic treatment after allogeneic hematopoietic stem cell transplantation. A multidisciplinary approach to the prevention and treatment of GVHD is important, and there are currently no preventive therapies available for ocular GVHD. Once diagnosed, ocular GVHD treatment strategies target ocular surface lubrication and support, tear film stabilization, inflammation reduction, and surgical intervention. The goal of this review is to define ocular GVHD and its categorical manifestations, as well as to describe the importance of comprehensive assessment, diagnosis, and ophthalmologic treatment and management of ocular GVHD with a multidisciplinary approach.

Efficacy and safety of belimumab in primary Sjögren's syndrome: results of the BELISS open-label phase II study.

BACKGROUND: Increased expression of B cell activating factor (BAFF or B lymphocyte stimulator) may explain the B cell activation characteristic of primary Sjögren's syndrome (pSS). OBJECTIVES: To evaluate the efficacy and safety of belimumab, targeting BAFF, in patients with pSS. METHODS: Patients were included in this bi-centric prospective 1-year open-label trial if they fulfilled American European Consensus group criteria, were anti-Sjögren's syndrome A-positive and had current systemic complications or salivary gland enlargement, or early disease (<5 years), or biomarkers of B cell activation. They received belimumab, 10 mg/kg, at weeks 0, 2 and 4 and then every 4 weeks to week 24. The primary end-point, assessed at week 28, was improvement in two of five items: reduction in ≥30% in dryness score on a visual analogue scale (VAS), ≥30% in fatigue VAS score, ≥30% in VAS pain score, ≥30% in systemic activity VAS assessed by the physician and/or >25% improvement in any B cell activation biomarker values. RESULTS: Among 30 patients included, the primary end-point was achieved in 18 (60%). The mean (SD) European League Against Rheumatism (EULAR) Sjögren's Syndrome Disease Activity Index decreased from 8.8 (7.4) to 6.3 (6.6) (p=0.0015) and EULAR) Sjögren's Syndrome Patient Reported Index from 6.4 (1.1) to 5.6 (2.0) (p=0.0174). The mean dryness, fatigue and pain VAS varied from 7.8 (1.8) to 6.2 (2.9) (p=0.0021), 6.9 (1.8) to 6.0 (2.2) (p=0.0606) and 4.6 (2.6) to 4.7 (2.4) (p=0.89), respectively. Salivary flow and Schirmer's test did not change. CONCLUSIONS: These encouraging results justify future randomised controlled trials of belimumab in a selected target population of pSS patients most likely to benefit from treatment.

Retrospective study of the prevalence of keratoconjunctivitis sicca in diabetic and nondiabetic dogs after phacoemulsification.

OBJECTIVE: To evaluate the prevalence of keratoconjunctivitis sicca (KCS) in diabetic and nondiabetic dogs following phacoemulsification. PROCEDURES: Medical records were reviewed for signalment, body weight, diabetes status, and STT at the preoperative and all postoperative examinations. A clinical diagnosis of KCS was defined as a STT <15 mm/min with compatible clinical signs. Schirmer tear test values and the prevalence of KCS based on STT <15 mm/min were evaluated at 2-4, 5-8, 9-14, 15-20, and 41-52 weeks postoperatively. Size of dog (large, >10 kg; small, ≤10 kg) and STT ranges (<15 mm/min, 15-22 mm/min and >22 mm/min) were categorized for analysis of effect of body weight and STT on prevalence of KCS. RESULTS: One hundred and seventeen nondiabetic (198 eyes) and 118 diabetic dogs (228 eyes) were evaluated. KCS was diagnosed in nearly twice as many diabetics as nondiabetics (27.4% vs. 15.4%) within 2 weeks postoperatively (P = 0.0088). Percentage of eyes with KCS among all dogs decreased over time and did not differ significantly after the first postoperative visit. Diabetic small dogs were 1.7 times more likely to have KCS than nondiabetic small dogs (P = 0.0052). Preoperative STT was significantly associated with likelihood of postoperative KCS among large (P < 0.0001), but not small dogs (P = 0.0781). Among large dogs, eyes with STTs between 15 and 22 mm/min were approximately 3 times more likely to be diagnosed with KCS after surgery than those with STT >22 mm/min. CONCLUSION: The greatest risk for KCS for all dogs is during the first 2 weeks postoperatively. Populations at greatest risk for postoperative KCS are small dogs, small diabetic dogs, and large dogs with preoperative STT ≤22.

Interleukin-1 receptor mediates the interplay between CD4+ T cells and ocular resident cells to promote keratinizing squamous metaplasia in Sjögren's syndrome.

Keratinizing squamous metaplasia (SQM) of the ocular mucosal epithelium is a blinding corneal disease characterized by the loss of conjunctival goblet cells (GCs), pathological ocular surface keratinization and tissue recruitment of immune cells. Using the autoimmune regulator (Aire)-deficient mouse as a model for Sjögren's syndrome (SS)-associated SQM, we identified CD4(+) T lymphocytes as the main immune effectors driving SQM and uncovered a pathogenic role for interleukin-1 (IL-1). IL-1, a pleiotropic cytokine family enriched in ocular epithelia, governs tissue homeostasis and mucosal immunity. Here, we used adoptive transfer of autoreactive CD4(+) T cells to dissect the mechanism whereby IL-1 promotes SQM. CD4(+) T cells adoptively transferred from both Aire knockout (KO) and Aire/IL-1 receptor type 1 (IL-1R1) double KO donors conferred SQM to severe-combined immunodeficiency (scid) recipients with functional IL-1R1, but not scid recipients lacking IL-1R1. In the lacrimal gland, IL-1R1 was primarily immunolocalized to ductal epithelium surrounded by CD4(+) T cells. In the eye, IL-1R1 was expressed on local mucosal epithelial and stromal cells, but not on resident antigen-presenting cells or infiltrating immune cells. In both tissues, autoreactive CD4(+) T-cell infiltration was only observed in the presence of IL-1R1-postive resident cells. Moreover, persistent activation of IL-1R1 signaling led to chronic immune-mediated inflammation by retaining CD4(+) T cells in the local microenvironment. Following IL-1R1-dependent infiltration of CD4(+) T cells, we observed SQM hallmarks in local tissues-corneal keratinization, conjunctival GC mucin acidification and epithelial cell hyperplasia throughout the ocular surface mucosa. Proinflammatory IL-1 expression in ocular epithelial cells significantly correlated with reduced tear secretion, while CD4(+) T-cell infiltration of the lacrimal gland predicted the development of ocular SQM. Collectively, data in this study indicated a central role for IL-1 in orchestrating a functional interplay between immune cells and resident cells of SS-targeted tissues in the pathogenesis of SQM.

Dacryocystorhinostomy precipitating keratoconjunctivitis sicca in aplasia of lacrimal and major salivary glands (ALSG).

We report a 16-month-old girl referred for bilateral epiphora and sticky eyes since birth. Examination revealed a refluxible left lacrimal sac mucocele, agenesis of the left lower punctum, and agenesis of both puncta on the right side. Complete bony obstruction was noted on probing of the left nasolacrimal duct. At 4 years of age, she underwent left external dacryocystorhinostomy (DCR) with silicone intubation because of chronic dacryocystitis. Her epiphora and stickiness improved significantly in the first postoperative year, but she subsequently developed dryness of the left eye, dry mouth, and dental caries. CT and MRI scans revealed the absence of the lacrimal and salivary glands. The clinical signs and symptoms improved with plugging the left upper punctum and topical lubricants. Aplasia of the lacrimal and salivary glands may present with symptoms of congenital lacrimal obstruction, and failure to make an early diagnosis will result in inappropriate lacrimal surgery and dry eye.

[Ocular involvement and its' manifestations in rheumatoid arthritis patients].

PURPOSE: To study the type, occurrence and nature of ocular involvement amongst patients with rheumatoid arthritis (RA), and to identify demographic, clinical and/or laboratory variables associated with eye involvement in RA. RESEARCH TYPE: Cross sectional research, retrospective METHODS: The research was conducted among 61 patients diagnosed with rheumatoid arthritis. The subjects were recruited for the research during their periodic visits to the Soroka Hospital Rheumatology Clinic. Comprehensive rheumatologic tests were administered and general health was examined with a prepared questionnaire. Additionally, the subjects' personal files were examined with data collected from general serum rheumatologic tests and details regarding medications administered. The patients were given a comprehensive eye examination, including a visual acuity examination, test for anterior and posterior fragments, a slit lamp examination after pupil dilation, for epithelial cell filaments, tests for dry eye symptoms, including a Schirmer's test, a tear breakup time test, and a corneal examination for epithelial cells and the existence of superficial punctate keratopathy. The subjects were also questioned regarding their dry eye syndrome and a specular microscopy test was performed. The assembled data was processed and analyzed with the aim of finding correlations between the subjective and objective sensations of dry eye symptoms and the activity of rheumatoid arthritis disease, blood tests, medications taken, and the patient's general state of health. RESULTS: The majority of the research subjects (90.2%) were women. Their average age was 51.9 +/- 13.21 years; 31.1% of the subjects complained of eye dryness and, during the eye examination, 85% were found to be suffering from dry eye. The study found a correlation between the objective indicators of keratitis sicca and the following parameters: laboratory values for SGOT (p < 0.03), ESR (p < 0.05), Cr (p < 0.05), TG (p < 0.03), LDL (p < 0.02), Hb (p < 0.01), ALP (p < 0.01), in addition to prednisone medication (p < 0.03, df = 2, x2 = 7.02) and methotrexate (p < 0.03, df = 2, x2 = 8.88). No correlation was found with the following parameters: age, disease duration, smoking, disease severity, other background diseases, and additional laboratory findings including RF and ANA measurements, and consuming other anti-rheumatoid arthritis medications. Similarly, no relation was found with the patients' various subjective syndromes. The average results of the specular microscopy test were 2116.15 +/- 416.59 for the right eye and 2125.67 +/- 446.14 for the left eye. CONCLUSIONS: The significance of the specular microscopy test results is that corneal damage found in rheumatoid arthritis patients occurs only to the external layer and does not affect the endothelial layer. The study indicates that keratitis sicca is prevalent among rheumatoid arthritis patients and must be taken into account regardless of the degree that the disease has progressed, because the severity of the dryness is not dependent on disease progression. Additionally, a discrepancy exists between the patients' subjective sensation of their eye condition and the objective findings of the study.

Clinical Profile in Genetically Proven Blau Syndrome: A Case Series from South India.

Purpose: To report the clinical profile of genetically proven Blau syndrome in seven cases from a single center in South India.Materials & Methods: Retrospective case seriesResults: There were four females and three males. All cases had a history of skin and joint involvement of varying severity. Flexion contractures of the proximal interphalangeal joints were seen in all cases except Case 2. Ocular involvement was bilateral and included keratoconjunctivitis sicca (six cases), granulomatous panuveitis (three cases), granulomatous anterior uveitis (three cases), conjunctival granulomas (three cases), subepithelial corneal opacities (one case), and subretinal granuloma (one case). Other ocular findings included band-shaped keratopathy (five cases) and cataract (three cases). All cases received oral steroids and methotrexate with an addition of mycophenolate mofetil in one case. Visual prognosis was good in all cases.Conclusions: Blau syndrome is underreported in India. This is the largest case series of genetically proven Blau syndrome from South India and highlights the clinical profile of Blau syndrome seen in India.

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.

[Inflammation of the conjunctiva]. / Bindehautentzündung.

Inflammations of the conjunctiva represent some of the most frequent eye diseases in general and ophthalmologic practice. Etiologically multiple diseases can be identified. A group of infectious conjunctivites contrasts with a very hereogeneous non-infectious group. Neoplastic processes such as low grade epithelial dysplasias and lymphomas may mascarade conjunctivitis. The differentiation of the various clinical pictures may be challenging for the practitioner. This article reviews the methodology of patient history and clinical work up as well as the symptomatology and treatment options for the most important conjunctivites in clinical practice.

Jupiter scleral lenses in the management of chronic graft versus host disease.

OBJECTIVES: To describe the use of the Jupiter scleral contact lens (Medlens Innovations, Front Royal, VA or Essilor Contact Lens, Inc., Dallas, TX) in the management of ocular manifestations of chronic graft versus host disease (cGVHD). METHODS: This study is a retrospective case series. Five consecutive patients with severe keratoconjunctivitis sicca (KCS) associated with cGVHD that could not be adequately managed with conventional therapy were evaluated for scleral contact lens wear between January and December 2007. All patients were evaluated with lenses from the standard 18.2 mm Jupiter B diagnostic fitting set. If lenses of standard design failed to provide adequate fit, custom lenses were designed. Three outcome measures were evaluated: the patient's ability to tolerate and successfully handle the lenses, improvement in symptoms of KCS, and improvement in visual acuity. RESULTS: All 5 patients (10 eyes) were successfully fit with Jupiter scleral lenses. Six eyes of 3 patients were successfully fit with lenses of standard design. Standard parameters were altered to achieve adequate fit in 4 eyes of 2 patients. All patients reported subjective improvements in comfort with Jupiter scleral lenses, and best-corrected vision improved in 7 of the 10 eyes fit within the first several months of contact lens wear. The remaining 3 eyes maintained the visual acuity measured before scleral lens wear (20/20 in 2 eyes, 20/40 in 1 eye). Duration of follow-up ranged from 4 to 14 months. CONCLUSIONS: Jupiter scleral lenses can relieve symptoms of KCS and may improve vision in patients with cGVHD.

Keratoconjunctivitis sicca attributable to parasympathetic facial nerve dysfunction associated with hypothyroidism in a horse.

CASE DESCRIPTION: A 6-year-old 680-kg (1,496-lb) German Warmblood gelding was evaluated because of bilateral blepharospasm and head shaking. CLINICAL FINDINGS: Moderate blepharospasm was evident bilaterally, and both eyes had hyperemic and edematous conjunctivas and lusterless corneas. For each eye, the Schirmer tear test value was only 7 mm/min. The horse's nasal mucosa was dry. Abnormal behaviors included mild repetitive vertical movement of the head, snorting, and flehmen response (classic signs of head shaking). Touching the horse's nostrils and face revealed paresthesia and dysesthesia with slight nasolabial muscle hypertrophy bilaterally. Cranial nerve examination revealed no other abnormalities. Serum thyroxine concentration was low, and results of thyrotropin-releasing hormone and thyroid-stimulating hormone stimulation tests were negative, indicating that the horse had hypothyroidism. The diagnoses included keratoconjunctivitis sicca and dry nares attributable to parasympathetic facial nerve dysfunction, head-shaking syndrome with paresthesia and dysesthesia of the face attributable to sensory trigeminal nerve disorder, and hypothyroidism. The 2 nerve dysfunctions were considered peripheral neuropathies that were most likely caused by hypothyroidism. TREATMENT AND OUTCOME: Treatment of both eyes was initiated with topical applications of cyclosporine, 0.5% sodium hyaluronate, and vitamin A ointment. Levothyroxine (20 microg/kg [9.1 microg/lb], PO, q 24 h) was administered. Within 3 weeks to 4 months, serum thyroxine concentration was within reference range, and clinical signs and Schirmer tear test values improved. CLINICAL RELEVANCE: Hypothyroidism should be considered as a differential diagnosis in horses with peripheral neuropathy or keratoconjunctivitis sicca. In affected horses, administration of levothyroxine may lead to resolution of neurologic signs.

Immunopathogenesis of keratoconjunctivitis sicca in the dog.

Keratoconjunctivitis sicca (KCS), more commonly known as dry eye, is an inflammatory condition of the ocular surface caused by a pathologic reduction in the aqueous component of the tear film. It is seen commonly in the dog and defined as a Schirmer tear test with a reading of less than 10 mm in one minute. While KCS may be caused by neurological disease or drug toxicity, most cases are immune-mediated. Whereas the immunological basis of autoimmune KCS has been extensively investigated in humans and experimental rodent models, little research has been undertaken in the dog. It is hoped that this review spurs further research into the etiopathogenic factors in canine KCS.

An unusual ocular presentation of acquired immune deficiency syndrome.

A 50-year-old male who presented with bilateral keratomalacia and on subsequent evaluation was found to be human immunodeficiency virus (HIV) positive is being reported. A MEDLINE search of the literature did not reveal any report of keratomalacia as the initial presenting feature of HIV/ acquired immune deficiency syndrome.

Dry eye syndrome (DES) and watering eyes.

Dry eye symptoms and watering eyes increase with age and are relatively common among older people. The conditions cause distress which can be ameliorated if patients are advised appropriately. Accurate diagnosis of the underlying cause provides the basis for management. This paper outlines key features of the conditions and the range of therapies available.