PURPOSE: Corneal infections, particularly fungal keratitis due to rare fungal species, pose a diagnostic and therapeutic challenge because of difficulty in identification and varying susceptibility profiles. In this study, we report the first case of fungal keratitis because of Exophiala phaeomuriformis. METHODS: We report the clinical findings and microbial identification techniques of a case of fungal keratitis due to E. phaeomuriformis. An 84-year-old woman presented with redness, pain, and itching in the left eye for 2 weeks. Slit-lamp biomicroscopy revealed one broken suture from previous penetrating keratoplasty (PKP), black infiltrates at the 4-o'clock position, without an overlying epithelial defect and hypopyon. Microbial identification was based cultures on Sabouraud dextrose agar and DNA sequencing and correlations to laser in vivo confocal microscopy (IVCM; Heidelberg Retinal Tomograph 3/Rostock Cornea Module, Heidelberg Engineering) and multiphoton microscopy (Ultima Microscope; Prairie Technologies) images. RESULTS: Slit-lamp biomicroscopy revealed one broken suture from previous PKP, black infiltrates at the 4-o'clock position, without an overlying epithelial defect and hypopyon. Based on a clinical suspicion of fungal keratitis, antifungals and fortified antibiotics were started. However, the patient did not respond to therapy and required urgent PKP. After surgery, the patient was maintained on topical and systemic voriconazole and also topical 2% cyclosporine for 5 months because of possibility of scleral involvement noticed during surgery. At the end of the treatment period, her vision improved from hand motion to 20/40, with no recurrence observed in a follow-up period of 1 year. Results of diagnostic tests were supported by fungal elements in stroma on IVCM. Culture from the infiltrate grew black yeast. DNA sequencing led to the diagnosis of E. phaeomuriformis keratitis. Antifungal susceptibility testing revealed sensitivity to voriconazole. CONCLUSION: This is, to our knowledge, the first reported case of E. phaeomuriformis fungal keratitis. Diagnostic testing included slit-lamp biomicroscopy, which revealed pigmented infiltrates, culture plates grew black yeast, microscopy showed branched fungal hyphae with budding conidia, and physiological features showed tolerance to high temperatures, nitrate assimilation, and ribosomal DNA sequencing. Collectively, these tests demonstrate unique features seen for this microorganism. High suspicion should be kept with pigmented infiltrates and with dark yeast on culture plates. Prompt and aggressive medical management with voriconazole or therapeutic PKP in nonresponsive cases is essential to prevent irreversible loss of vision.
Mesenchymal stem cells (MSCs) possess distinct immunomodulatory properties and have tremendous potential for use in therapeutic applications in various inflammatory diseases. MSCs have been shown to regulate pathogenic functions of mature myeloid inflammatory cells, such as macrophages and neutrophils. Intriguingly, the capacity of MSCs to modulate differentiation of myeloid progenitors to mature inflammatory cells remains unknown to date. Here, we report the novel finding that MSCs inhibit the expression of differentiation markers on myeloid progenitors under inflammatory conditions. We demonstrate that the inhibitory effect of MSCs is dependent on direct cell-cell contact and that this intercellular contact is mediated through interaction of CD200 expressed by MSCs and CD200R1 expressed by myeloid progenitors. Further, using an injury model of sterile inflammation, we show that MSCs promote myeloid progenitor frequencies and suppress infiltration of inflammatory cells in the inflamed tissue. We also find that downregulation of CD200 in MSCs correlates with abrogation of their immunoregulatory function. Collectively, our study provides unequivocal evidence that MSCs inhibit differentiation of myeloid progenitors in the inflammatory environment via CD200-CD200R1 interaction. This article is protected by copyright. All rights reserved.
The function of the meibomian gland in the upper and lower eyelids is critical to maintaining homeostasis at the ocular surface. Highly specialized meibocytes within the gland must differentiate and accumulate intracellular lipid droplets that are released into the tear film following rupture of the cell membrane. Proteases and their inhibitors have been recognized as key players in remodeling extracellular matrices and promoting the normal integrity of glandular tissue. They modulate a wide range of biological processes, such as cell proliferation and differentiation, and can contribute to disease when aberrantly expressed. Deciphering the role of proteolytic activity in the meibomian gland offers an opportunity to gain a more comprehensive and fundamental understanding of the developmental, physiological, and pathological processes associated with this gland.
OBJECTIVE: This case series is the first to describe divergence palsy as an adverse effect of antiepileptic drug use. Diplopia is a common adverse effect of antiepileptic drugs, but no explanatory motility deficit has ever been reported. METHODS: We present 2 patients, 1 on oxcarbazepine and 1 on divalproex, each with a normal examination result between spells and divergency palsy when symptomatic. RESULTS: Discontinuation of the antiepileptic medication led to resolution of the episodes in both cases. Rechallenge with the offending agent after washout in one patient resulted in recurrence of diplopia and divergence palsy, both resolving after subsequent withdrawal of the antiepileptic. CONCLUSIONS: Antiepileptic drugs may cause divergence palsy.
There are no data in the literature regarding the safety of re-treatment with ethambutol for recurrent mycobacterial infection after prior ethambutol-induced optic neuropathy. We describe a patient who developed optic neuropathy attributed to ethambutol, recovered fully after drug withdrawal, and tolerated a 14-month long re-treatment 10 years later without developing recurrent optic neuropathy.
Photoreceptors are sensory neurons designed to convert light stimuli into neurological responses. This process, called phototransduction, takes place in the outer segments (OS) of rod and cone photoreceptors. OS are specialized sensory cilia, with analogous structures to those present in other nonmotile cilia. Deficient morphogenesis and/or dysfunction of photoreceptor sensory cilia (PSC) caused by mutations in a variety of photoreceptor-specific and common cilia genes can lead to inherited retinal degenerations (IRDs). IRDs can manifest as isolated retinal diseases or syndromic diseases. In this review, we describe the structure and composition of PSC and different forms of ciliopathies with retinal involvement. We review the genetics of the IRDs, which are monogenic disorders but genetically diverse with regard to causality.
Fenofibrate, a specific agonist of peroxisome proliferator-activated receptor alpha (PPARα), displays robust therapeutic effects on diabetic retinopathy (DR) in type 2 diabetic patients. Our recent studies have shown that PPARα is down-regulated in the diabetic retina, which contributes to the pathogenesis of DR. However, the mechanism for diabetes-induced down-regulation of PPARα remains unknown. We investigated the role of microRNA-21 (miR-21) in regulating PPARα in DR. MiR-21 was over-expressed, while PPARα levels were decreased in the retina of db/db mice, a type 2 diabetic model. Such alterations were also observed in palmitate-treated retinal endothelial cells. MiR-21 targeted PPARα by inhibiting its mRNA translation. Knockout of miR-21 prevented the decrease of PPARα, alleviated microvascular damage, ameliorated inflammation and reduced cell apoptosis in the retina of db/db mice. Intravitreal injection of miR-21 inhibitor attenuated PPARα down-regulation and ameliorated retinal inflammation in db/db mice. Further, retinal miR-21 levels were increased, while PPARα levels were decreased in oxygen-induced retinopathy (OIR). Knockout of miR-21 prevented PPARα down-regulation and ameliorated retinal neovascularization and inflammation in OIR retinas. In conclusion, diabetes-induced over-expression of miR-21 in the retina is responsible, at least in part, for PPARα down-regulation in DR. Targeting miR-21 may represent a novel therapeutic strategy for DR.
The roles of transforming growth factor (TGF)-β in extracellular matrix production and vascular remodeling, coupled with increased TGF-β expression and signaling in diabetes, suggest TGF-β as an important contributor to the microangiopathy of diabetic retinopathy and nephropathy. To investigate whether increased TGF-β signaling could be a therapeutic target for preventing retinopathy, we used a pharmacologic approach (SM16, a selective inhibitor of the type 1 TGF-β receptor activin receptor-like kinase 5, orally active) to inhibit the increased, but not the basal, Tgf-β signaling in retinal vessels of diabetic rats. At the level of vascular gene expression, 3.5 months' diabetes induced minimal changes. Diabetes + SM16 for 3 weeks caused widespread changes in gene expression poised to enhance vascular inflammation, thrombosis, leakage, and wall instability; these changes were not observed in control rats given SM16. The synergy of diabetes and SM16 in altering gene expression was not observed in the lung. At the level of vascular network morphology, 7 months' diabetes induced no detectable changes. Diabetes + SM16 for 3 weeks caused instead distorted morphology and decreased density. Thus, in diabetes, retinal vessels become dependent on a small increase in TGF-β signaling via activin receptor-like kinase 5 to maintain early integrity. The increased TGF-β signaling may protect against rapid retinopathy progression and should not be a target of inhibitory interventions.
PURPOSE: V-pattern strabismus observed with syndromic craniosynostosis has been attributed to disparate causes. We compared severity of V pattern with degree of excyclorotation of rectus muscles to appraise significance of this proposed aetiology. METHODS: 43 patients with Apert, Crouzon or Pfeiffer syndrome referred to Boston Children's Hospital Department of Ophthalmology were identified. 28 met inclusion criteria for retrospective cohort study, specifically: (1) sensorimotor measurements in minimum of seven cardinal gazes, (2) quantified fundus torsion and (3) orbital CT imaging sufficient to measure rectus muscle cyclorotation in coronal and quasicoronal planes, posteriorly (near orbital apex) and anteriorly (near pulleys). Patients were placed in one of four V-pattern severity groups. The most severe group demonstrated inability to elevate abducted eye above midline with characteristic 'seesaw' misalignment during horizontal saccades. Rectus muscle cyclorotation was measured by paediatric neuroradiologist blinded to group placement. Primary outcome was correlation of severity of V pattern with degree of excyclorotation. Secondary outcome was correlation of severity with craniosynostosis syndrome. RESULTS: Increasing severity of V pattern correlated with greater excyclorotation in anterior coronal (p=0.009), anterior quasicoronal (p=0.021), posterior coronal (p=0.014) and posterior quasicoronal (p=0.040) planes for moderate-to-severe V pattern. Even greater excyclorotation was associated with seesaw V pattern in anterior quasicoronal (p=0.004) and posterior quasicoronal (p=0.001) views. Highly significant association was found between Apert syndrome and severity of V pattern (p=0.004). CONCLUSIONS: Severity of V pattern is associated with magnitude of excyclorotation. More severe V pattern and seesaw strabismus noted with Apert syndrome may relate to distinctive orbital morphology.
Ideally, biomaterials designed to play specific physical and physiological roles in vivo should comprise components and microarchitectures analogous to those of the native tissues they intend to replace. For that, implantable biomaterials need to be carefully designed to have the correct structural and compositional properties, which consequently impart their bio-function. In this study, we showed that the control of such properties can be defined from the bottom-up, using smart surface templates to modulate the structure, composition, and bio-mechanics of human transplantable tissues. Using multi-functional peptide amphiphile-coated surfaces with different anisotropies, we were able to control the phenotype of corneal stromal cells and instruct them to fabricate self-lifting tissues that closely emulated the native stromal lamellae of the human cornea. The type and arrangement of the extracellular matrix comprising these corneal stromal Self-Lifting Analogous Tissue Equivalents (SLATEs) were then evaluated in detail, and was shown to correlate with tissue function. Specifically, SLATEs comprising aligned collagen fibrils were shown to be significantly thicker, denser, and more resistant to proteolytic degradation compared to SLATEs formed with randomly-oriented constituents. In addition, SLATEs were highly transparent while providing increased absorption to near-UV radiation. Importantly, corneal stromal SLATEs were capable of constituting tissues with a higher-order complexity, either by creating thicker tissues through stacking or by serving as substrate to support a fully-differentiated, stratified corneal epithelium. SLATEs were also deemed safe as implants in a rabbit corneal model, being capable of integrating with the surrounding host tissue without provoking inflammation, neo-vascularization, or any other signs of rejection after a 9-months follow-up. This work thus paves the way for the de novo bio-fabrication of easy-retrievable, scaffold-free human tissues with controlled structural, compositional, and functional properties to replace corneal, as well as other, tissues.
A 49-year-old woman with a known right optic disc cavernous hemangioma experienced pain with eye movements and worsening of a superior visual field defect. While she retained 20/20 visual acuity in each eye, findings on magnetic resonance imaging were consistent with a hemorrhage in the anterior portion of the right intraorbital optic nerve. Her visual function stabilized spontaneously. We are unaware of previous reports of hemorrhage into the optic nerve from a cavernous hemangioma of the optic disc.
PURPOSE: Inherited retinal dystrophies are a significant cause of vision loss and are characterized by the loss of photoreceptors and the retinal pigment epithelium (RPE). Mutations in approximately 250 genes cause inherited retinal degenerations with a high degree of genetic heterogeneity. New techniques in next-generation sequencing are allowing the comprehensive analysis of all retinal disease genes thus changing the approach to the molecular diagnosis of inherited retinal dystrophies. This review serves to analyze clinical progress in genetic diagnostic testing and implications for retinal gene therapy. METHODS: A literature search of PubMed and OMIM was conducted to relevant articles in inherited retinal dystrophies. RESULTS: Next-generation genetic sequencing allows the simultaneous analysis of all the approximately 250 genes that cause inherited retinal dystrophies. Reported diagnostic rates range are high and range from 51% to 57%. These new sequencing tools are highly accurate with sensitivities of 97.9% and specificities of 100%. Retinal gene therapy clinical trials are underway for multiple genes including RPE65, ABCA4, CHM, RS1, MYO7A, CNGA3, CNGB3, ND4, and MERTK for which a molecular diagnosis may be beneficial for patients. CONCLUSION: Comprehensive next-generation genetic sequencing of all retinal dystrophy genes is changing the paradigm for how retinal specialists perform genetic testing for inherited retinal degenerations. Not only are high diagnostic yields obtained, but mutations in genes with novel clinical phenotypes are also identified. In the era of retinal gene therapy clinical trials, identifying specific genetic defects will increasingly be of use to identify patients who may enroll in clinical studies and benefit from novel therapies.
Painless low-grade right proptosis with 20/25 visual acuity developed slowly in a 49-year-old woman with a past history of breast cancer. Imaging studies disclosed an oval-to-round superotemporal mass in the right lacrimal fossa without bone erosion. Excisional biopsy revealed a pseudoencapsulated, bosselated tumor with a spindled, hypocellular, and heavily periodic acid Schiff-positive stroma constituted of abundant basement membrane material and collagen. Scattered lumens and focal cribriform cellular clusters were present in the peripheries of several of the lobules. Immunohistochemistry showed epithelial membrane antigen+ and cytokeratin (CK) 7+ in many small luminal structures. The spindled cells were calponin+, CK5/6+, CK14+, and p63+, confirming their myoepithelial nature. The Ki67 proliferation index was 2-3%, and upregulation of nuclear p53, a tumor suppressor gene product which may be aberrantly overexpressed in malignancy, was observed in rare cells. Immunohistochemical probes for HMGA2 and PLAG1 oncoproteins, characteristic of pleomorphic adenoma, were stained intensely and less intensely, respectively. MYB and c-KIT (CD117) were negative, thereby strongly arguing against the diagnosis of adenoid cystic carcinoma. In atypical epithelial tumors of the lacrimal gland, genetic probes identifying distinctive gene translocations or their oncoprotein products complement traditional immunohistochemical biomarkers such as cytokeratins and other structural or secretory molecules. Characteristic genetic abnormalities demonstrated by immunohistochemistry for their upregulated protein products, or by in situ hybridization for translocations, are increasingly being relied on for diagnostic precision.
Primary orbital natural killer T-cell lymphoma (NKTCL) is a rare condition with only a few published cases in the literature. Over 1 month, an 81-year-old man developed progressive left periocular inflammation unresponsive to treatment. Clinical examination and imaging studies demonstrated a left lacrimal gland enlargement. Bilateral anterior uveitis and erythematous nontender cutaneous lesions were also found. Biopsies of the skin and lacrimal gland on the back revealed histopathologic and immunohistochemical findings confirming Epstein-Barr virus-positive NKTCL. Metastatic work up disclosed multifocal involvement in the pancreas, stomach, and chest wall. Palliative treatment consisting of nonanthracycline-based chemotherapy and radiation was instituted, but the patient died 5 months after the onset of symptoms. This is the first example of acute dacryoadenitis, and the second of bilateral anterior uveitis, in the setting of NKTCL. Absence of naso-sinus involvement in the current case is rare in NKTCL. Despite treatment, the prognosis remains dismal. Orbital specialists should include NKTCL in the differential diagnosis of lacrimal gland/orbital masses and perform an incisional biopsy if the clinical scenario so dictates.