[Uveitis intermedia in childhood]. / Uveitis intermedia im Kindesalter.

Round 10-12% of all children who present with signs of uveitis suffer from intermediate uveitis. Compared to uveitis anterior in children, the association of intermediate uveitis to a systemic disease is much more complicated. Most cases of uveitis intermedia are idiopathic and show the signs of a pars planitis. Post-infectious and immunological causes are difficult to detect. In cases of uveitis in children, it is necessary to know the specific symptoms of possible underlying systemic diseases. On this basis, an adequate and specific diagnosis will most probably be successful. This paper presents the different causes of uveitis intermedia in childhood and compares the incidence of the disease in comparison with adults as far as this is mentioned in the literature.

[Diagnostics in childhood uveitis: what tests for which uveitis?]. / Diagnostik bei Uveitis im Kindesalter: Welche Tests bei welcher Uveitis?

BACKGROUND: Intraocular inflammation in children differs considerably from that found in adults. Therefore the diagnostic work-up has to be adapted to the age and specific diseases. MATERIALS AND METHODS: The published literature was reviewed for results of clinical trials and consensus meetings. In addition, the authors have incorporated their own experience. RESULTS: Recommendations for a systematic and complete diagnostic work-up are given using tables where possible. CONCLUSIONS: A close cooperation between ophthalmologists and paediatricians is very important.

Interferon as a treatment for uveitis associated with multiple sclerosis.

AIM: In addition to optic neuritis (ON), multiple sclerosis (MS) may also involve the eye with a typically bilateral intermediate uveitis. The aim of this pilot study was to evaluate the efficacy of type I interferons (IFN) for the treatment of MS associated uveitis. METHODS: In this non-randomised, retrospective observational case series 13 patients (eight female, five male) with proved MS and associated uveitis from five uveitis centres who were treated with interferon beta1a were included. Visual acuity (VA), cell count in the aqueous humour and vitreous, as well as the presence of cystoid macula oedema (CMO) were observed. RESULTS: All except one patient had a bilateral form of intermediate uveitis (total of 24 eyes). Seven patients had documented CMO before IFN treatment (n = 13 eyes). Median duration of treatment was 24.6 months (range 7.9-78.7). VA improved in 17 eyes (comparing VA before therapy and at last follow up); while 10 eyes (36%) improved >or=3 Snellen lines. Aqueous cell count improved by 1.2 (SD 1.1) grades in all eyes. Vitreous cell count improved by 1.7 (1.4) in all eyes. Only two patients still had minimal CMO on last follow up angiographically. CMO resolved after or during IFN treatment in nine eyes. CONCLUSIONS: IFN has been shown to have beneficial effects in patients with MS and/or ON. As shown in the models of experimental allergic encephalomyelitis (EAE) and uveitis, the neurological and ophthalmological manifestations seem to share similar pathogenic mechanisms. Treatment of MS associated uveitis with IFN appears to have beneficial effects on VA, intraocular inflammation activity, and the presence of CMO.

Adenoviral p53 gene transfer inhibits human Tenon's capsule fibroblast proliferation.

BACKGROUND/AIM: Although antiproliferative drugs have been used successfully to prevent scarring after filtration surgery in patients with glaucoma, complications associated with their use (such as hypotony or endophthalmitis) energise the search for an alternative treatment. Single application of beta radiation leads to long term growth arrest and expression of p53 in human Tenon's capsule fibroblasts (hTf). The authors assume that the activation of p53 is one of the cellular triggers. Their aim was to analyse the effect of p53 overexpression on hTf and to determine which pathways are involved. METHODS: A recombinant adenoviral vector (rAd.p53) containing transgenes encoding for human p53 and green fluorescent protein (GFP) was used to induce overexpression of p53 in hTF and a control vector (rAd.GFP). Transgene expression was detected by western blot (p53 and p21WAF-1/Cip1). Cell proliferation and viability were investigated using cell counts, 5'-bromodeoxyuridine incorporation (BrdU assay) and tetrazolium reduction (MTT assay). RESULTS: Infection of hTf with rAd.p53 resulted in significant inhibition of cell proliferation, DNA synthesis, and metabolic activity in vitro. Western blot showed increased levels of p53 and p21WAF-1/Cip1 in rAd.p53 infected cells, but not in rAd.GFP and uninfected cells. Apoptosis was excluded with flow cytometry. CONCLUSIONS: Adenoviral p53 gene transfer leads to significant growth inhibition in hTf. P53 induces p21(WAF-1/Cip1) expression and does not cause apoptosis in hTf in vitro. p53 as an antiproliferative drug has the potential to replace mitomycin C and 5-fluorouracil in glaucoma surgery.

[Vision-threatening complications in childhood uveitis]. / Visusmindernde Komplikationen bei Uveitis im Kindesalter.

PURPOSE: We analyzed the epidemiologic data and vision-threatening complications in different forms of childhood uveitis. METHODS: This retrospective study included 187 consecutive patients with onset of uveitis before the age of 16 years classified as anterior (AU), intermediate (IU), posterior (PU), and panuveitis (PanU). We analyzed the epidemiologic data as well as visual acuity, uveitic complications and the conservative and surgical therapy. RESULTS: Associated disease was observed in 85 of 187 patients. The most common complications in AU patients were cataract, posterior synechiae, band keratopathy and CME. IU was accompanied by dense vitreous opacities, cataract and CME. Macular scars were the most frequent cause for visual loss in PU. PanU was complicated by dense vitreous opacities, cataract, retinal detachment, CME and phthisis bulbi. CONCLUSIONS: Childhood uveitis is frequently associated with systemic immune-mediated diseases. The diverse uveitis types have different but typical complications.

Mycophenolate mofetil inhibits human Tenon fibroblast proliferation by guanosine depletion.

BACKGROUND/AIM: Mycophenolate mofetil could be a useful antiproliferative drug in glaucoma filtering surgery. In this study the authors set out to investigate whether growth inhibition of mycophenolate mofetil on human Tenon fibroblasts is mediated by guanosine depletion. METHODS: Cultured human Tenon fibroblasts were incubated in various concentrations of mycophenolate mofetil with and without supplementation of guanosine. RESULTS: Growth inhibition was concentration dependent. The effect could be completely antagonised by guanosine supplement. CONCLUSION: Human Tenon fibroblasts depend on the de novo synthesis pathway of guanosine. No sufficient salvage pathway from purine degradation appears to exist.

Modulation of hydrogen peroxide induced injury to corneal endothelium by virus mediated catalase gene transfer.

AIM: To examine the effect of catalase gene transfer on survival of corneal endothelial cells (EC) following challenge with hydrogen peroxide (H(2)O(2)) in an ex vivo model of oxidative stress. METHODS: A recombinant adenovirus vector (AdCL) was used to transfer human catalase cDNA into EC of whole thickness rabbit corneas ex vivo. The resulting catalase protein concentration was measured in corneal lysates by ELISA; catalase functional activity in lysates was determined using a H(2)O(2) activity assay. To examine the morphological effects of catalase gene transfer in modulation of H(2)O(2) induced injury, transduced corneas were maintained in ex vivo culture and challenged with H(2)O(2). Laser scanning confocal microscopy was used to image EC injury. Cell density, cell morphology, and ratios of viable to necrotic cells were determined. RESULTS: Following incubation with AdCL, catalase expression reached maximum at 5-7 days. Corneas transduced with AdCL showed increased EC cell survival following challenge with H(2)O(2) on day 3 when compared to null vector control or mock infected corneas. CONCLUSIONS: Ex vivo catalase gene transfer can protect EC from death mediated by H(2)O(2). This gene based approach to the protection of corneal endothelium from oxidative stress may have application in prevention of EC loss in pathological conditions in which H(2)O(2) is involved and in ex vivo donor corneal storage before transplantation.

Cytokine and chemokine expression kinetics after corneal transplantation.

BACKGROUND: Allogeneic rejection is the most common cause of corneal graft failure. The aim of this work was to establish the kinetics of cytokine and chemokine mRNA expression before and after onset of corneal graft rejection. METHODS: Intracorneal cytokine and chemokine mRNA levels were investigated in the Brown Norway-->Lewis inbred rat model in which rejection onset is observed at 8/9 days after grafting in all animals. Nongrafted corneas and syngeneic (Lewis-->Lewis) corneal transplants were used as controls. Donor and recipient cornea was examined by quantitative competitive reverse transcription-polymerase chain reaction (RT-PCR) for hypoxyanthine phosphoribosyltransferase (HPRT), CD3, CD25, interleukin (IL)-1beta, IL-1RA, IL2, IL-6, IL-10, interferon-gamma (IFN-gamma), tumor necrosis factor (TNF), transforming growth factor (TGF)-beta1, and macrophage inflammatory protein (MIP)-II and by nonquantitative RT-PCR for IL4, IL-5, IL-12 p40, IL-13, TGF-beta2, monocyte chemotactic protein-1 (MCP-1), MIP-1alpha, MIP-1beta, and RANTES (for regulated upon activation normal T cell expressed and secreted). RESULTS: A biphasic expression of cytokine and chemokine mRNA was found after transplantation. During the early phase (days 3-9), there was an elevation of the majority of the cytokines examined, including IL-1beta, IL-6, IL-10, IL-12 p40, and MIP-II. There was no difference in cytokine expression patterns between allogeneic or syngeneic recipients at this time. In syngeneic recipients, cytokine levels reduced to pretransplant levels by day 13, whereas levels of all cytokines rose after observed rejection onset in the allografts, including TGF-beta1, TGF-beta2, and IL-1RA. The T cell-derived cytokines IL-4, IL-13, and IFN-gamma were detected only during the rejection phase in allogeneic recipients. CONCLUSIONS: There is an early cytokine and chemokine response to the transplantation process, evident in syngeneic and allogeneic grafts, that probably drives angiogenesis, leukocyte recruitment, and affects leukocyte functions. After an immune response has been generated, allogeneic rejection results in the expression of Th1 cytokines (IL-2, IL-12 p40, IFN-gamma), Th2 cytokines (IL-4, IL-6, IL-10, and IL-13), and antiinflammatory/Th3 cytokines (TGF-beta1/2 and IL-1RA).

Gene delivery to the corneal endothelium.

Gene transfer to the corneal endothelium has potential for modulating rejection of corneal grafts. It can also serve as a convenient and useful model for gene therapy of other organs. In this article we review the work carried out in our laboratory using both viral and nonviral vectors to obtain gene expression in the cornea.

Adeno-associated and herpes simplex viruses as vectors for gene transfer to the corneal endothelium.

PURPOSE: We examined the efficacy and cytopathogenicity of adeno-associated (AAV) and herpes simplex viruses (HSV) as vectors for gene transfer to corneal endothelial cells (CECs). METHODS: Recombinant AAV and HSV were examined for their ability to deliver a lacZ histochemical marker gene to whole-thickness rabbit and human corneas ex vivo. Transgene expression was detected with histochemistry and quantified by a colorimetric assay. RESULTS: Rabbit and human corneas transduced with AAV showed increasing numbers of cells expressing marker gene over a 3- to 4-week period. Using 2.5 x 10(6) or 1.5 x 10(7) infective units for rabbit and human corneal specimens, respectively, approximately 2% of CECs expressed the reporter gene. HSV (10(6) plaque-forming units/specimen) transduced approximately 5% of rabbit and human CECs but showed cytotoxicity. In contrast to the duration of recombinant AAV-mediated lacZ expression, recombinant HSV expression was maximal at day 1 and declined to low levels at day 7. CONCLUSION: AAV is a promising vector, but its usefulness for corneal transduction is currently limited by the technical difficulties preparing high titres. The HSV vector examined is efficient but needs further genetic modification to prolong transgene expression and reduce its toxicity.

Randomised controlled trial of corticosteroid regimens in endothelial corneal allograft rejection.

AIM: To determine whether the addition of systemic corticosteroid to local intensive corticosteroid therapy of endothelial corneal allograft rejection improves outcome. METHODS: A prospective randomised treatment trial was carried out at a tertiary referral centre. 36 consecutive corneal graft recipients, presenting with a first episode of endothelial graft rejection, received either (i) one intravenous pulse of methylprednisolone 500 mg in addition to local corticosteroid treatment, or (ii) local treatment only. The regimen of local treatment standardised in all cases for the first 24 hours consisted of one subconjunctival betamethasone 2 mg injection and dexamethasone 0.1% drops in the affected eye every hour for 24 hours. RESULTS: Failure to reverse the graft rejection episode was found in 3/36 (8%) patients. Each of these had been treated with local steroid only. Graft failure from any cause occurred in 9/36 (25%) within 2 years of follow up. No statistically significant difference was found between the two groups with regard to reversal of the graft rejection episode, later recurrence of graft rejection, or graft failure. CONCLUSIONS: In treatment of graft rejection, additional systemic treatment with 500 mg methylprednisolone yields no significant benefit over intensive local corticosteroid alone. Graft survival following treatment of a rejection episode with local corticosteroid treatment alone is good in those patients without other risk factors for graft failure and much higher than reported previously.

Activated polyamidoamine dendrimers, a non-viral vector for gene transfer to the corneal endothelium.

We investigated the efficiency of activated polyamidoamine dendrimers, a new class of nonviral vectors, to transfect rabbit and human corneas in ex vivo culture. In addition to assessing the expression of a marker gene we have demonstrated that this approach can be used to induce the production of TNF receptor fusion protein (TNFR-Ig), a protein with therapeutic potential. Whole thickness rabbit or human corneas were transfected ex vivo with complexes consisting of dendrimers and plasmids containing lacZ or TNFR-Ig genes. Following optimisation 6-10% of the corneal endothelial cells expressed the marker gene. Expression was restricted to the endothelium and was maximal after transfection with 18:1 (w/w) activated dendrimer:plasmid DNA ratio and culture for 3 days. The supernatant of corneas transfected with TNFR-Ig plasmid contained TNFR-Ig protein which was able to inhibit TNF-mediated cytotoxicity in a bioassay. We have therefore shown that activated dendrimers are an efficient nonviral vector capable of transducing corneal endothelial cells ex vivo. They may have applications in gene-based approaches aimed at prevention of corneal allograft rejection or in treatment of other disorders of corneal endothelium.

[Gene transfer in ophthalmology]. / Gentransfer in der Augenheilkunde.

BACKGROUND: Research into the molecular and genetic basis of disease is continually expanding. How does the increasing knowledge about the genetic basis of eye diseases contribute to the development of new therapeutic strategies? MATERIALS AND METHODS: Gene therapy, here defined as the introduction of genetic material into human cells, offers great opportunities. Gene transfer strategies can be used for gene replacement in recessive disease, gene inactivation in dominant disease, expression of "rescue factors" and apoptosis modulators in degenerative disease, "suicide genes" for example in proliferative diseases and expression of immunmodulatory factors in immunological disorders. Viral vector systems have been developed to introduce the gene of interest into the target cell. RESULTS: Most of the published strategies include the use of vectors for gene transfer. Adenovirus (AV), adenoassociated virus (AAV), encapsulated adenovirus mini-chromosomes (EAMs), herpes simplex virus (HSV) and lentiviruses are the most frequently used viral vector systems to date. Their advantages and disadvantages, the in vivo models used for gene transfer in retinal degeneration, and the results obtained to date by different research groups in the field will be reviewed. CONCLUSIONS: Gene transfer into ocular tissues has been demonstrated with growing functional success and may develop into a new therapeutic tool for clinical ophthalmology.

[Intravitreal injection of cidofovir in cytomegalovirus retinitis]. / Intravitreale Injektion von Cidofovir bei CMV-Retinitis.

BACKGROUND: CMV retinitis is the most common opportunistic ocular infection and the main cause of blindness in AIDS patients with a T-helper cell count < or = 50/microliter. Cidofovir is a nucleotide analogue with a long half-life time after phosphorylation intracellularly. It is effective against CMV and can be given intravenously and intravitreally. The aim was to offer an alternative therapy for CMV retinitis to patients who could not receive standard treatment because of contraindications or refused it. The efficacy and tolerance of intravitreal injections of cidofovir should be evaluated. PATIENTS AND METHODS: We treated 16 eyes of 12 patients. The total number of injections with 15 micrograms of cidofovir each was 49, with an average of 3 injections per eye. The duration of follow-up was 75-295 days (median 170 days). Probenecid was given concomitantly. Injections were repeated after 6-10 weeks. Secondary prophylaxis of CMV organ infection was done with oral ganciclovir. RESULTS: Within a few days all areas with active retinitis turned into scars following the first injection. Under consequent treatment no reactivation was observed. Four eyes developed a mild iritis with hypotony within a mean time of 12 days after injection. All responded rapidly to topical steroids. None had a persisting loss of vision. Two eyes developed cystoid macular edema (CME). Two patients stopped anti-CMV treatment (ganciclovir orally and injections), followed by a recurrence after an average of 64-days. CONCLUSIONS: Intravitreal injection therapy with 15 micrograms cidofovir and concomitant oral probenecid is a valuable and safe alternative treatment for CMV retinitis in AIDS patients. Its main complication is iritis with hypotony, which is effectively treatable with topical steroids. No complications caused by the injection technique itself were noted. The occasional observation of CME in otherwise quiet eyes, however, is probably drug-related.

[Acute retinal necrosis syndrome. Argon laser coagulation for prevention of rhegmatogenic retinal detachment]. / Akutes Retinanekrose (ARN)-Syndrom. Argon-Laser-Koagulation (ALK) zur Prophylaxe rhegmatogener Netzhautablösungen.

BACKGROUND: ARN syndrome follows severeintraocular infection by herpes viruses and primarily affects the peripheral retina. Following scar formation, despite antiviral treatment, rhegmatogenous retinal detachment occurs very often. Prophylactic argon laser photocoagulation has therefore been proposed. We report our experience. PATIENTS: We treated five patients presenting clinically with advanced unilateral ARN with acyclovir. All eyes received a prophylactic confluent double row of argon laser treatment (500 microns, 0.2 s, gray-white lesions) central to the affected area as soon as was possible, depending on the vitreous clouding. Four patients were treated with Aspirin. RESULTS: One of the five patients had a peripheral rhegmatogenous retinal detachment that was limited by the argon laser row. Another patient had a tractional detachment needing vitreoretinal surgery. Two eyes developed vitreal hemorrhage of unknown origin. CONCLUSION: A lower rate of rhegmatogenous retinal detachments than expected occurred post-laser treatment. Vitreal hemorrhage was more frequent than previously reported. The bleeding probably originated from anterior retinal neovascularization and may have been enhanced by Aspirin treatment. We recommend early prophylactic argon laser photocoagulation in all ARN patients in agreement with the results of previous studies.

Prophylactic argon laser coagulation for rhegmatogenous retinal detachment in AIDS patients with cytomegalovirus retinitis.

BACKGROUND: The incidence of cytomegalovirus (CMV) retinitis in patients with acquired immunodeficiency syndrome (AIDS) reaches 20-45%. Despite aggressive medical treatment, rhegmatogenous retinal detachments develop in up to 30% of the affected eyes. Surgical repair is often difficult due to multiple large and hardly visible retinal holes with vitreal traction. Pars plana vitrectomy with instillation of silicone oil is the procedure of choice, giving limited functional results with anatomical reattachment. METHODS: We performed prophylactic laser coagulation in AIDS patients with medically treated CMV retinitis to prevent a progressive retinal detachment. Twenty-two quiescent CMV lesions in 22 eyes of 20 patients were treated with argon green laser coagulation. Each CMV lesion was completely surrounded with a double or triple row of laser spots (500-600 mumols; 0.2 s; gray-white lesions). RESULTS: The duration of follow-up was 2-24 months. Histopathologic evaluation was possible in two eyes of one patient. Reactivated or smoldering CMV retinitis crossed the laser scars in 11 eyes, making additional laser coagulation necessary. In four eyes retinal holes in the CMV scar tissue led to retinal detachment, which stopped at the laser scar. In three eyes the detachment is still controlled by the laser scar. In one eye, the detachment stopped at the laser scar for 6.5 months and then slowly progressed across it. There were no complications associated with our laser treatment. CONCLUSION: Prophylactic argon laser coagulation in quiescent CMV retinitis seems to reduce the rate of progressive retinal detachment with no need for vitrectomy and silicone oil tamponade.

[Corneoscleral transplant excision in the cadaver. Experiences of the North Rhine Westphalia Lions Cornea Bank 1995 and 1996]. / Korneosklerale Transplantatentnahme an der Leiche. Erfahrungen der Lions-Hornhautbank Nordrhein-Westfalen in den Jahren 1995 und 1996.

BACKGROUND: Donor corneas are normally obtained by whole globe enucleation-a procedure often refused by the bereaved. To increase the acceptance of cornea donation, we have exclusively obtained donor corneas by in situ excision since the end of 1994. There have been reports of increased endothelial damage and higher contamination rates. We report our experience in 1995 and 1996. METHODS: The in situ excision was performed by staff trained in microsurgical techniques. Only donor corneas with negative end-storage cultures after at least 10 days and an endothelial cell count of more than 2500 cells/mm2 were used for transplantation. RESULTS: In all, 705 corneoscleral buttons were excised from 1/95 to 12/96. The bereaved consented in 34% in 1996. A total of 30.5% of the corneas were ineligible for transplantation which corresponds to the discard figures from all cornea banks with culture methods. We did not observe any primary transplant failure nor endophthalmitis after 444 perforating keratoplasties. CONCLUSION: In situ corneal excision is safe, and helps to reduce the shortage in donor corneas.