Are intravitreal injections essential during the COVID-19 pandemic? Global preferred practice patterns and practical recommendations

Tertiary outpatient ophthalmology clinics are high-risk environments for COVID-19 transmission, especially retina clinics, where regular follow-up is needed for elderly patients with multiple comorbidities. Intravitreal injection therapy (IVT) for chronic macular diseases, is one of the most common procedures performed, associated with a significant burden of care because of the vigorous treatment regimen associated with multiple investigations. While minimizing the risk of COVID-19 infection transmission is a priority, this must be balanced against the continued provision of sight-saving ophthalmic care to patients at risk of permanent vision loss. This review aims to give evidence-based guidelines on managing IVT during the COVID-19 pandemic in common macular diseases such as age-related macular degeneration, diabetic macula edema and retinal vascular disease and to report on how the COVID-19 pandemic has affected IVT practices worldwide.

To illustrate some real-world examples, 18 participants in the International Retina Collaborative, from 15 countries and across four continents, were surveyed regarding pre- and during- COVID-19 pandemic IVT practices in tertiary ophthalmic centers. The majority of centers reported a reduction in the number of appointments to reduce the risk of the spread of COVID-19 with varying changes to their IVT regimen to treat various macula diseases. Due to the constantly evolving nature of the COVID-19 pandemic, and the uncertainty about the normal resumption of health services, we suggest that new solutions for eye healthcare provision, like telemedicine, may be adopted in the future when we consider new long-term adaptations required to cope with the COVID-19 pandemic.

[What will cataract surgery look like in the future? Alternatives in the pipeline]

Phacoemulsification is the most frequently performed surgery in the world. Over the past few years, this surgery seems to have reached a plateau with no further innovative breakthroughs. In this paper, we focus on alternatives techniques, the latest innovations, and the research and development pipeline in this field.

First-in-human study of the safety and viability of intraocular robotic surgery

Microsurgery of the retina would be dramatically improved by instruments that offer supra-human precision. Here, we report the results of a first-in-human study of remotely controlled robot-assisted retinal surgery performed through a telemanipulation device. Specifically, 12 patients requiring dissection of the epiretinal or inner limiting membrane over the macula were randomly assigned to either undergo robot-assisted-surgery or manual surgery, under general anaesthesia. We evaluated surgical success, duration of surgery and amount of retinal microtrauma as a proxy for safety. Surgical outcomes were equally successful in the robotic-surgery and manual-surgery groups. Differences in the amount of retinal microtrauma between the two groups were statistically insignificant, yet dissection took longer with robotic surgery (median time, 4 min 5 s) than with manual surgery (1 min 20 s). We also show the feasibility of using the robot to inject recombinant tissue plasminogen activator under the retina to displace sight-threatening haemorrhage in three patients under local anaesthesia. A safe and viable robotic system for intraocular surgery would enable precise and minimally traumatic delivery of gene therapy or cell therapy to the retina.

The additional value of blood culture bottles in the diagnosis of endophthalmitis

PURPOSE

To assess the additional value of blood culture bottles (BCBs) in the diagnosis of endophthalmitis by comparing its culture yield with that of conventional media (CM).

DESIGN

Retrospective consecutive case series.

METHODS

We included patients who were treated between January 2001 and January 2010 for clinically suspected endophthalmitis of any etiology, and had vitreous specimens cultivated in both BCB and CM.

RESULTS

Specimens from 85 eyes from 85 patients were included. The culture yield of BCB was 69%, and that of CM was 72% (difference not significant). Adding the results of BCB improved the yield of CM significantly by 13%, resulting in a combined yield of 81%. The sensitivity of detection of Haemophilus influenzae in BCB seemed lower compared with CM, possibly due to the lack of growth factors in the BCB. There was no difference in yield between specimens obtained by tap or by vitrectomy.

CONCLUSION

In contrast with earlier reports, we did not find BCB superior to CM. The combined use of BCB and CM increased the pathogen detection rate significantly and should therefore be considered as the microbiological method of choice in the work-up of endophthalmitis.

Uveitic macular oedema: correlation between optical coherence tomography patterns with visual acuity and fluorescein angiography

AIMS

(1) To associate optical coherence tomography (OCT) patterns with particular fluorescein angiography (FA) findings in uveitis patients with macular oedema. (2) To investigate the correlation between tomographic features and visual acuity (VA). (3) To determine the impact of OCT patterns on visual improvement over time.

METHODS

129 eyes of 90 patients followed for uveitis with macular oedema and adequate media clarity were consecutively included from February to November 2004. We examined the relationship between VA, the fluorescein angiograms grading and central thickness.

RESULTS

Mean retinal thickness at the central fovea was 357 (SD 128) microm. The mean VA was 0.5 (logMAR). There was agreement between OCT and FA in 112 eyes (86.8%). In eight eyes (6.2%), serous retinal detachment (SRD) was detected on OCT but not on FA. Nine eyes (7%) had perifoveal leakage on FA without macular thickening on OCT. There were three patterns of macular oedema on OCT: diffuse macular oedema (DMO), cystoid macular oedema (CMO) and SRD. CMO was detected in 61 eyes (50.8%), and in 18 of these eyes (15%), CMO was associated with SRD. DMO was detected in 45 eyes (37.5%), and in eight (6.7%) of these eyes, DMO was associated with SRD. SRD without retinal thickening was present in 14 eyes (11%). Epiretinal membrane was detected by OCT in 27 eyes (21%). Six eyes demonstrated vitreomacular traction (4.7%). There was a correlation between VA and central thickness on OCT (r = 0.407, p = 0.000001). Correlation between VA and central thickness is significant in the group with CMO (r = 0.401, p = 0.001) but not significant in the group with DMO. Furthermore, vision recovery was observed in patients with CMO but was limited in patients with DMO. SRD did not have a significant impact on visual recovery, but its presence reduced the correlation between vision and central thickness.

CONCLUSION

OCT is effective in detection of macular oedema. It allows determination of the distribution of fluid and quantification of retinal thickness particularly in patients with CMO. In these patients, a potential for vision recovery was also identified. DMO was associated with a poor visual prognosis and a poor prognosis for vision recovery. SRD is associated with a high probability of vision recovery when observed alone or underlying CMO eyes. It should be substracted from the central thickness measurement when attempting to correlate central thickness with vision in patients with macular oedema in uveitis.

Minimally invasive surgery—endoscopic retinal detachment repair in patients with media opacities

PURPOSE

Evaluate the use of an ophthalmic endoscope in patients with a retinal detachment and anterior media opacity.

MATERIALS AND METHODS

A retrospective interventional case series. Search of a comprehensive database of retinal detachment patients with pre-operatively impaired anterior segments such that lens extraction, a keratoprosthesis, or extensive anterior segment manipulation was required for adequate repair. Pars plana vitrectomy was carried out with an endoscope without manipulation of the anterior segment. Characteristics of the detachment were recorded, as were complications/subsequent surgeries, pre-operative, 3-month post-operative, and final follow-up visual acuities.

RESULTS

Before surgery, five patients had a gas-induced cataract after a failed pneumatic retinopexy; one patient had a Reis-Buckler's dystrophy and corneal ulcer; three patients had synechiae around iris-fixed lenses. One patient had proliferative vitreoretinopathy. The median pre-operative vision was hand motion (20/30 to light perception). The median final visual acuity was 20/30 (20/20-20/200). Two patients required a subsequent lens extraction, one patient had a recurrent detachment.

CONCLUSION

In appropriate retinal detachment patients, endoscopy can be safe and effective, while limiting the scope of the surgical intervention.

Influence of cataract on optical coherence tomography image quality and retinal thickness

BACKGROUND

As optical coherence tomography (OCT) is widely used for diagnosis and monitoring of ocular pathology, especially in the elderly people, the influence of cataract on image quality and macular retinal thickness was studied.

METHODS

In 29 patients scheduled for cataract surgery, preoperative and postoperative OCT scans were obtained. Cataracts were categorised as nuclear, posterior or cortical. Parameters for image quality (signal-to-noise ratio (SNR)) and signal strength and macular thickness were compared. A three-level expert grading scale was used to evaluate the discriminative abilities of SNR and signal strength.

RESULTS

Nuclear cataracts (n = 12) provided better preoperative scans (higher SNR/signal strength) than posterior (n = 7) and cortical (n = 10) cataracts (p<0.004). Postoperatively SNR and signal strength increased significantly in all patients (p<0.001). The SNR was better at discriminating poor from acceptable and good scans than signal strength (area under the receiver operating curve: 0.879 and 0.810, respectively). Postoperative macular thickness overall showed a significant increase (p = 0.005), most evident in patients with posterior cataracts (p = 0.028).

CONCLUSIONS

OCT imaging is influenced by cataract; image quality is reduced preoperatively and macular thickness measurements are slightly increased postoperatively. In individual patients, OCT scans remain reliable for gross clinical interpretation, even in the presence of cataract.

Precursor B lymphoblastic lymphoma of the orbit in a child: an unusual presentation of a non-Hodgkin lymphoma

OBJECTIVE

The majority of ocular adnexal lymphomas are marginal zone lymphomas, which occur rarely in children. This case report describes a 6 years old child with a precursor B lymphoblastic lymphoma presenting in the ocular adnexa. The combination of multi-agent chemotherapy with adjuvant radiotherapy seems to be necessary in order to achieve a complete remission of this subtype of lymphoma's in ocular adnexa.

DESIGN

Retrospective case study.

METHOD

A review of the clinical, pathological, radiological findings and follow-up in a patient from the files available at our center, which were reviewed between the years 1974 and 2004.

Added value of OCT in evaluating the presence of leakage in patients with age-related macular degeneration treated with PDT

BACKGROUND

Evaluating the presence of leakage on fluorescein angiography (FA) in patients with age-related macular degeneration (AMD) retreated with photodynamic therapy (PDT) can be difficult. New diagnostic tools such as optical coherence tomography (OCT) might help to optimize PDT management.

METHODS

Thirty AMD patients scheduled for regular follow-up FA in conjunction with PDT treatment were also scanned with OCT. Follow-up data at 9 months were retrieved from the patients' medical records. Inter-observer agreement [kappa coefficient] for the presence of leakage on FA, for OCT parameters for leakage, and agreement between FA and OCT evaluations were calculated. The indication for retreatment was evaluated using the leakage analysis based on FA alone, OCT alone, and both examinations combined, and compared to the actual follow-up of the patients at 9 months.

RESULTS

Agreement between the two observers for the presence of leakage on FA was moderate (kappa=0.51). OCT agreement between the two observers for the presence of leakage was good (kappa=0.85). Agreement between FA and OCT for the presence of leakage was poor (kappa=0.16). Follow-up data at 9 months on all patients were analyzed. Seven out of 30 patients were not retreated at the time of examination, and four of these patients (57%) remained stable without further treatment. Twenty-three patients did receive a PDT treatment at the time of examination; and eight of these patients did not show leakage on OCT, and five of these patients (62%) remained stable without additional treatment. In contrast, only three out of 15 patients (20%) with leakage on both FA and OCT remained stable during this 9 month follow-up period.

CONCLUSIONS

Inter-observer agreement for the presence of leakage was moderate for FA and good for OCT. There was considerable disagreement between leakage as judged by OCT and by FA. OCT could be of help in the decision regarding PDT retreatment. Assuming that 57% of the patients without leakage either on FA or OCT would remain stable without retreatment, the rate of probable ineffective retreatment could be reduced from 35% to 20%.

Single spot PDT in patients with circumscribed choroidal haemangioma and near normal visual acuity

BACKGROUND

In circumscribed choroidal hemangiomas (CCH) a long observation period and decreased visual acuity before treatment are risk factors for poor visual outcome. Therefore, we studied the use of limited, single spot photodynamic therapy (PDT) with Visudyne for the timely treatment of CCH.

METHODS

Six consecutive patients with CCH, and metamorphopsia but (near) normal visual acuity were treated with PDT, using a single spot covering only the most prominent part of the tumour, and a radiance exposure of 50 J/cm(2). Start of treatment was 6 min following a 1-min infusion with Visudyne (6 mg/m(2) BSA), using a diode laser (692 nm).

RESULTS

In all patients, the metamorphopsia disappeared, the OCT images returned to a normal foveal contour, and visual acuity remained 20/20 or improved to 20/20. In five patients, the tumour became ultrasonographically undetectable; in three after one PDT session, in one patient after two and in another patient after three PDT sessions. The last patient had a residual tumour height of 1.2 mm, but no metamorphopsia, a normal foveal contour on OCT, and fluorescein angiography showed no residual leakage.

CONCLUSION

The present series demonstrates that single spot PDT might be an effective treatment for CCH with a visual acuity > or =20/30, without serious side-effects during a follow-up of at least 18 months.

Evaluation of central serous retinopathy with en face optical coherence tomography

BACKGROUND

The diagnosis of idiopathic central serous retinopathy (CSR) is usually based on biomicroscopy and fluorescein angiography (FA). The optical coherence tomography (OCT) ophthalmoscope produces en face OCT scans (OCT C-scans) and provides additional information not readily available by conventional imaging techniques. The authors describe the characteristic features observed in patients with a clinical diagnosis of CSR using the OCT ophthalmoscope.

METHODS

38 eyes with a clinical diagnosis of CSR, seen at the Academic Medical Centre (Amsterdam, Netherlands) and the New York Eye and Ear Infirmary (New York, USA) between August 2002 and March 2004, were evaluated with standard digital FA and scanned with the OCT ophthalmoscope.

RESULTS

Nine of 38 eyes had no serous neurosensory detachment (inactive CSR) when scanned with the OCT ophthalmoscope. Characteristics for active CSR (n=29) were large neurosensory detachment (23/29), subretinal hyper-reflective depoits (20/29), and pigment epithelial detachment (15/29). One third of the patients, either active or inactive, had multiple small pigment epithelial detachments located both within and outside the neurosensory detachment.

CONCLUSION

The OCT ophthalmoscope provides complementary morphological information on patients with CSR. The presence of more diffuse retinal pigment epithelium (RPE) changes lends further support to the concept that CSR is a diffuse rather than localised RPE anomaly.

Actualités sur les modalités thérapeutiques des uvéites

The immunosuppression required for the treatment of uveitis can be achieved through conventional agents or through the use of specific modulators of inflammation. Whatever the choice, it is important to limit side effects: by restricting access to certain drugs in patients presenting a high risk of complications (tuberculosis screening before using Remicade), reducing side effects through preventive measures (use of alendronates during oral corticotherapy), or choosing a local delivery route (intraocular triamcinolone). Intraocular triamcinolone has certain beneficial characteristics such as high local dosage without systemic effect. However, it can cause a pressure rise in 10% to 20% of patients. It requires certain precautions when given to prevent development of a pseudo-endophthalmitis. Remicade is a novel synthetic immunosuppressant directed against TNF-alpha. This chimeric antibody can be useful in the treatment of severe uveitis that is unresponsive to conventional therapy. It is currently being tested in clinical trials in uveitis both in Europe and the USA.

The surgical management of chronic hypotony due to uveitis

PURPOSE

Evaluate surgery in chronic hypotony secondary to uveitis.

METHOD

Retrospective analysis of six patients operated for chronic hypotony (< or =5 mmHg) of at least 1 month's duration. Surgery involved removal of all traction and membranes on the ciliary processes. Use of oil was limited to patients with atrophic ciliary processes.

RESULTS

The average postoperative follow-up was 24 months (12-43). The average pressure increase was 7 mmHg at 6 months. Four of six uveitis patients had significantly increased vision.

CONCLUSION

Improved vision, and a sustained pressure rise are possible in hypotonous uveitis. The presence of ciliary processes is necessary. However, they do not need to be intact.

Longstanding symptomatic choroidal hemangioma managed with limited PDT as initial or salvage therapy

PURPOSE

To describe the use of limited, low-irradiance, single-spot photodynamic therapy (PDT) with verteporfin for the treatment of symptomatic choroidal hemangiomas.

METHODS

Thirteen consecutive patients with a circumscribed choroidal hemangioma were treated with limited PDT 6 min following a 1-min infusion with verteporfin (6 mg/m(2) body surface area), using a diode laser (692 nm) and a single spot large enough to cover only the most prominent part of the tumor. Exposure time was 166 s in the first three patients and 83 s in the last ten patients, resulting in a radiance exposure of respectively 100 and 50 J/cm(2).

RESULTS

In all 11 not previously conventionally treated patients, visual acuity improved following PDT treatment. The two remaining patients with prior radiation treatment both reported widening of the visual field and sharper vision, but did not show an increase in ETDRS vision. In all but four patients the tumor became ultrasonographically undetectable by the first follow-up visit at 6 weeks, with only a slight irregularity at the level of the previous tumor remaining. In four patients the residual tumor was still detectable, and they received a second treatment, following which the tumor flattened completely. In all patients the retinal detachment disappeared.

CONCLUSION

The present series demonstrates that even limited, low-irradiance, single-spot photodynamic therapy with verteporfin is an effective first-line treatment for choroidal hemangiomas.

[Intravitreal chemotherapy for intraocular lymphoma]

Primary CNS and intraocular non-Hodgkin's lymphoma is currently mostly treated with systemic chemotherapy. After initially successful tumor regression, recurrence is common and usually treated with radiotherapy. However, after good primary therapeutic response, new tumor growth is frequently observed. Because of actinic complications, radiotherapy can be applied only once. For an intraocular recurrence of primary CNS and intraocular lymphoma, intravitreal chemotherapy (0.4 mg methotrexate and 0.4 mg dexamethasone weekly for 4 weeks and once a month thereafter) can be performed. A few weeks after initiation, regression of intraocular tumors and eventually improvement of vision can be achieved. Eyes remained free of recurrence up to 2 years after initiation of intravitreal injections. Intravitreal chemotherapy is an effective treatment for ocular recurrence of primary CNS and intraocular lymphoma after systemic chemotherapy and radiotherapy.

[Eye complaints indicative of a tumor elsewhere in the body]

A variety of clinical presentations of malignant tumour metastases outside of the eye and orbit, were seen in four patients: a 52-year-old man who was scheduled to have a surgical removal of an oesophageal carcinoma and who presented with retinal detachment, a 58-year-old woman in whom retinopathy was the first sign of a cervical carcinoma (cancer-associated retinopathy), a 71-year-old man who had been treated for colon carcinoma and who presented with an orbital mass, and finally a 67-year-old woman with an orbital mass as the first sign of a Grawitz tumour. Metastasis should be considered in patients with a history of malignancy, who present with ophthalmologic complaints. Further it should be borne in mind that eye problems can be the first sign of oncological disease outside the eye.

Human S-antigen determinant recognition in uveitis

PURPOSE

Soluble antigen (S-Ag) is a member of the arrestin family of protein with which it shares a high level of homology. It is an immunologically privileged retinal antigen that can elicit experimental autoimmune uveitis (EAU) and is thought to be a target for ocular inflammatory diseases. This study was conducted to identify in humans, the immunogenic determinants of human S-Ag and to establish whether a specific response profile occurs in particular ocular inflammatory conditions.

METHODS

Peripheral blood lymphocyte responses were measured against a panel of 40 overlapping synthetic peptides of human S-Ag in patients with chronic uveitis and compared with control subjects. Patients with Behçet disease, sarcoidosis, Vogt-Koyanagi-Harada, and sympathetic ophthalmia were tested.

RESULTS

A limited number of immunodominant determinants were identified for Behçet disease and sarcoidosis. These were all located at sites of limited homology with other known arrestins. In addition, several individual patients had prominent proliferative responses to multiple determinants well above that of control subjects. This determinant spread was observed in all disease entities except sympathetic ophthalmia, which did not show any immunoreactivity to S-Ag. Significant response shifts were also noted over time in two patients.

CONCLUSIONS

The results indicate that there are specific immunodominant determinants to human S-Ag in patients with certain forms of uveitis. However, in individual patients, response is not limited to these determinants. In the chronic stage of disease, response is spread over many determinants.

Regulation of ocular inflammation--what experimental and human studies have taught us

Study of models of ocular autoimmunity and of autoimmune uveitis in humans has lead to a shift in the perceived nature of immune privilege from one based on anatomical isolation of the eye to a more dynamic, active process of immune tolerance. Using a variety of available models, the basis for this dynamic process of immune regulation is reviewed. The protective role of humoral immunity, the co-stimulatory function of B cells in EAU as well as the influence of cytokines within the inflammatory cascade are outlined. Modulation of the immune response and in particular the possible role of macrophages is explored. Within the current paradyme, a major effector cell is the CD4+ lymphocyte. Its maturation into a Th1 or Th2 phenotype process appears dependent on a number of exogenous factors, which while genetically determined can be manipulated prior to disease onset. Activation of CD4+ cells is dependent on presentation of immunoreactive peptide fragments. These fragments are well characterized in the Lewis rat for S-Ag and interphotoreceptor retinoid binding protein (IRBP). Mapping of the immunoreactivity to S-Ag has been recently completed in uveitis patients. An overlap with certain determinants identified in experimental models has been observed, in at least 2 disease entities. However, the response profile is not fixed in time and is subject to determinant spread. Future studies will be aimed at identifying with more detail immunologic triggers of inflammation in patients, and at better defining the interplay between effector and regulatory pathways both in the eye and in the systemic circulation.

Adenocarcinoma of the esophagus with choroidal metastasis

In this report, a case is presented of an adenocarcinoma in a Barrett's esophagus metastatic to the choroid. A 54-year-old woman presented with a rapidly progressive decrease of vision in the right eye 8 months after intentionally curative esophagectomy for an adenocarcinoma. Fundoscopy, ultrasonography, and magnetic resonance imaging findings were suggestive of a metastasis. The patient received palliative external beam irradiation to the right eye for visual restoration, but she died before any beneficial effect was achieved.

Management of non Hodgkin's intraocular lymphoma with intravitreal methotrexate

Intraocular non Hodgkin's lymphoma has traditionally been treated with radiotherapy or systemic chemotherapeutic agents. Unfortunately, radiotherapy rarely leads to a long term remission, and can only be safely administered once. Systemic chemotherapy has limited intraocular penetration. Intravitreal administered methotrexate is highly effective at inducing remission and is well tolerated. A case report is presented of a recurrent intraocular lymphoma following radiotherapy and systemic chemotherapy which responded to a combination of intravitreal methotrexate and dexamethasone. A response was seen within three weeks of treatment initiation. Toxicity was limited to the progression of a pre-existing cataract. Review of the literature shows that intravitreal methotrexate is well tolerated, with few acute complications. However, with monotherapy, local recurrences have been observed.

Circulating antibodies to inducible heat shock protein 70 in patients with uveitis

Heat shock proteins with molecular weight 70 kDa (hsp70) are highly conserved immunogenic intracellular molecules. There are two main subtypes: one is expressed constitutively (hsc70), while the other is induced under stressful conditions (ihsp70). Using an ELISA directed against recombinant human ihsp70, antibody titers were determined in patients with defined ocular inflammatory conditions (Behçet's disease, Vogt-Koyanagi-Harada (VKH), pars planitis, and sarcoidosis) as well as in a group of age-matched normal volunteers. In comparison to healthy controls (n = 14, absorbance 0.269), levels were significantly elevated in Behçet's disease (n = 18; 0.412), sarcoidosis (n = 15; 0.432), and pars planitis (n = 13; 0.346), but not in VKH (n = 10; 0.263). A correlation was also noted for treatment versus no treatment in pars planitis (p = 0.028), but not in other inflammatory conditions. There was no correlation with the level of intraocular disease activity as defined by vitreous haze and vision drop. Since pars planitis is a purely ocular condition, circulating levels of ihsp antibodies likely reflect the extent of disease involvement within the eye.

Prevalence of subclinical anterior uveitis in adult patients with inflammatory bowel disease

AIM

To assess the prevalence of subclinical anterior uveitis in adult patients with inflammatory bowel disease.

METHODS

In 179 consecutive patients (96 with Crohn's disease, 55 with ulcerative colitis, and 28 with inflammatory bowel disease of undetermined nature) without previous or concurrent ocular complaints, quantitative flare measurements were obtained with the Kowa FC laser flare to detect the presence of subclinical uveitis.

RESULTS

The mean flare value was 3.9 (SD 1.1) ph/ms in patients younger than 30 years of age, rising to 5.8 (2.5) ph/ms in those over 60 years of age. No measurement performed in this patient population fell outside the mean observed value plus or minus SD of the normal controls within the same age category.

CONCLUSION

In an adult population of 179 consecutive patients with inflammatory bowel disease the presence of a form of subclinical uveitis, as described by Hofley et al in a group of juvenile patients, is highly unlikely.

[Two children with extrapulmonary symptoms due to tuberculosis]

Two patients came to their general practitioner for relatively minor problems: a 4-year-old boy came with a red eye and a 10-year-old girl with red foot soles. They came from Pakistan and Vietnam respectively. Their symptoms were due to tuberculosis, which diagnosis was established by Mantoux test and culture of a stomach aspirate. They were treated accordingly with isoniazid, rifampicin and pyrazinamide and with isoniazid, rifampicin and ethambutol respectively. These cases stress the importance of knowledge of the extrapulmonary manifestations of tuberculosis. As treatment exists and adequate treatment can diminish the reservoir of tuberculosis bacteria, early diagnosis can prevent the morbidity, spread and mortality of tuberculosis.

Prospective determination of T-cell responses to S-antigen in Behçet's disease patients and controls

PURPOSE

To prospectively determine, using two different assays, the lymphocyte proliferative response to a retinal autoantigen (S-antigen) in patients with Behçet's disease who are under treatment for ocular inflammation.

METHODS

Patients were evaluated at each visit for signs of ocular inflammation. Peripheral blood leukocytes were harvested and cultured in the presence of bovine S-antigen in a standard culture assay, as well as by limiting dilution using multiple short-term T-cell lines.

RESULTS

Five patients were observed for 2 to 10 months. During follow-up, three patients had episodes of ocular inflammation. No consistent change in proliferative response was observed in standard proliferation assays. However, an increase in established T-cell lines was correlated to the presence of ocular inflammation in all three patients. Ocular activity was associated with an increase of 9- to 30-fold in the frequency of short-term T-cell lines. This increase returned to baseline within 1 to 3 months.

CONCLUSIONS

An increase in S-antigen-responsive lymphocytes is found in the peripheral blood of patients with Behçet's disease during episodes of ocular inflammation. This increase cannot be measured using standard proliferation assays but requires the use of techniques exploiting the principles of limiting dilution analysis.

Iris involvement in primary intraocular lymphoma: report of two cases and review of the literature

Non-Hodgkin's lymphoma involves ocular tissues either as a primary tumor or as secondary metastasis from systemic disease. Diagnosis is based on the identification of malignant cells in the eye by biopsy. Although primary intraocular lymphoma cells have been identified in the optic nerve, ciliary body, and iris of a small number of patients by histopathology, these sites of infiltration have rarely been observed on clinical examination. We studied clinical and histopathological findings of two patients with iris infiltration by primary intraocular lymphoma and reviewed the findings of 163 cases reported in the literature.

Fomivirsen - a phosphorothioate oligonucleotide for the treatment of CMV retinitis

Fomivirsen is a 21-nucleotide phosphorothioate oligonucleotide which, when injected into a human eye, is capable of inhibiting CMV retinitis. Its mode of action is consistent with an antisense mechanism. Prior to human trials, fomivirsen was tested in a number of in vitro cell lines and was found to inhibit CMV replication in a dose-dependent manner with a mean 50% inhibitory concentration between 0.03 and 0.2 microM. Intravitreal drug clearance studies have revealed first-order kinetics with a half-life in the rabbit of 62 hours. In a clinical trial of patients with newly diagnosed CMV retinitis receiving 165 mg per injection, time to progression was interpolated to 71 days with 44% of the patients remaining on treatment for over one year. In patients who failed other anti-CMV treatments, the interpolated time to progression was 91 days when receiving 330 mg per injection. No systemic absorption of the drug could be detected. Reported adverse events have been for the most part mild to moderate in intensity and either resolved spontaneously or were treatable with topical medications. Locally administered fomivirsen effectively inhibits CMV retinitis using a mode of action which is complementary to existing DNA polymerase inhibitors.

Influence of highly active antiretroviral therapy on the development of CMV disease in HIV positive patients at high risk for CMV disease

BACKGROUND/AIMS

In the pre-HAART era, HIV positive patients with CD4+ cell counts below 50 cells x10(6)/l, and those with detectable cytomegalovirus (CMV) DNA in their peripheral blood, were considered to be at high risk for the development of CMV disease. With the start of highly active antiretroviral therapy (HAART), a restoration of immune function occurred in these patients, and as a consequence patients became less vulnerable to CMV disease. Since it is not exactly known how HAART influences CMV viral load in peripheral blood and the incidence of CMV disease in high risk HIV positive patients a group of patients was followed before and after initiation of HAART.

METHODS

29 HIV positive patients, seen in the first 3 months of 1996 at the AIDS clinic of the Academic Medical Centre, at high risk for development of CMV disease (positive CMV DNA assay in blood and/or CD4+ cell count below 50 cells x10(6)/l), not receiving anti-CMV maintenance therapy, were included in a prospective cohort study. HAART was started in the second trimester of 1996. Patients were evaluated for the occurrence of CMV retinitis, or CMV disease elsewhere, comparing the incidence of CMV events before and after the start of HAART. Following the introduction of HAART, CD4+ cell counts and quantitative polymerase chain reaction (PCR) for CMV DNA in blood were monitored in all patients who remained alive and were not receiving anti-CMV maintenance therapy (n=22). Follow up was performed until August 1998; the mean follow up after the start of HAART was 14.9 months (range 8-22 months).

RESULTS

In the pre-HAART period four patients developed CMV disease, and four died (without clinically manifest CMV disease). After the start of HAART no patient developed CMV disease or died. With HAART, the mean CD4+ cell counts increased from 34 cells x10(6)/l to 194 cells x10(6)/l at the end of follow up. CMV DNA could be detected in the blood of 11 patients. Quantification showed a decline in the amount of detectable DNA during follow up. At the last examination only one patient showed a positive PCR assay. This was the only patient with a CD4+ cell count remaining below 100 cells x10(6)/l.

CONCLUSION

In HIV positive patients at high risk of CMV retinitis, either with a positive CMV PCR assay in blood and/or with CD4+ cell counts below 50 cell x10(6)/l, HAART causes a dramatic decrease in the occurrence of CMV disease. This decrease is paralleled by an increase in CD4+ cell count, and a decrease in the amount of CMV DNA in the blood, which was below detection levels in all patients with CD4+ cell counts above 100 cells x10(6)/l.

Aetiological study of the presumed ocular histoplasmosis syndrome in the Netherlands

AIM

To investigate whether presumed ocular histoplasmosis syndrome in the Netherlands is caused by Histoplasma capsulatum and whether other risk factors might play a role in the pathogenesis of this syndrome.

METHODS

23 patients were clinically diagnosed as having presumed ocular histoplasmosis syndrome based on the following criteria: peripapillary atrophy, punched out lesions, a macular disciform lesion or scar in one eye without vitritis. As controls, 66 sex and age matched healthy volunteers were used. Serum samples from both patients and controls were tested for the presence of antibodies against H capsulatum, Toxoplasma gondii, Toxocara canis et cati, Ascaris sp, and for the presence of antigens of Cryptococcus neoformans. Serum samples were also tested for the presence of autoantibodies against retinal or choroidal proteins. To investigate other risk factors, patients and controls were asked to fill in a health and travel related questionnaire. Ten patients with ocular toxoplasmosis were used as a disease control group.

RESULTS

None of the patients with presumed ocular histoplasmosis syndrome or controls had circulating antibodies directed against H capsulatum. No risk factors could be identified and no indications for autoimmunity and no evidence for the role of the other infectious agents could be demonstrated.

CONCLUSIONS

In a Dutch group of patients fulfilling the criteria of a disease currently named presumed ocular histoplasmosis syndrome, no risk factors or relation with the fungus H capsulatum could be detected.

Intravitreal chemotherapy for the treatment of recurrent intraocular lymphoma

AIM

To develop and assess a protocol for the treatment of intraocular lymphoma by intravitreal injection of methotrexate and thiotepa.

METHODS

A patient with intraocular non-Hodgkin's lymphoma which recurred after radiotherapy and repeated systemic chemotherapeutic regimens underwent repeated intravitreal injections of methotrexate and thiotepa. The patient was closely monitored by cytology, anterior chamber flare measurements, IL-10 and IL-6 levels. Methotrexate drug clearance studies were performed on vitreous samples taken before each injection.

RESULTS

Complete tumour clearance was achieved by the third week of therapy. IL-10 and IL-6 levels quickly dropped to barely detectable levels as the tumour was cleared from the eye. Flare measurements decreased from 500 to 15 photons/s over the same time. A plot of the methotrexate levels over time revealed a first order kinetic rate of elimination with an effective tumoricidal intravitreal dose persisting for 5 days after injection.

CONCLUSION

Intravitreal chemotherapy for the treatment of recurrent intraocular lymphoma appears effective in prolonging local remission of ocular disease even in the presence of an aggressively growing tumour. A single intravitreal injection of methotrexate can lead to a prolonged tumoricidal concentration lasting for a longer period than that achieved by systemic administration.

Treatment of uveitis with recombinant human interleukin-13

AIM

To evaluate the anti-inflammatory cytokine interleukin-13 (IL-13) for the treatment of uveitis.

METHODS

Uveitis was induced in monkeys by immunisation with human retinal S-antigen. Starting at the onset of disease, the animals were treated with IL-13 at 25 micrograms/kg, or vehicle control, injected subcutaneously once a day for 28 days. Intraocular inflammation was scored by indirect ophthalmoscopy for a period of 56 days. Circulating leucocyte levels were monitored.

RESULTS

Uveitis started unilaterally in all but one animal. IL-13 inhibited inflammation both in the eyes in which the disease was present when the treatment was initiated (p = 0.0001), and in the contralateral initially negative eyes (p = 0.0001). After cessation of therapy, there was a progressive increase of inflammation in the IL-13 treated group. However, the beneficial effect of IL-13 extended into the 4 week follow up period. IL-13 produced an increase in circulating polymorphonuclear neutrophils and a decrease in lymphocytes.

CONCLUSION

Administration of IL-13 appears to be a promising modality of treatment for severe uveitis.

A novel method for the determination of T-cell proliferative responses in patients with uveitis

Standard proliferation assays using autoantigens such as S-Ag have given erratic responses when studied with human peripheral blood mononuclear cells. This erratic response is a reflection of the low number of circulating cells in the peripheral blood capable of generating a response as well as the presence of competing cells for the available cytokines in culture. The present study compares the standard proliferation assay with a novel technique in which multiple short-term cell lines are established to S-Ag in medium enriched in helper cytokines. After 12-14 days of culture, these lines were tested for their response to S-Ag. A significant difference was found between patients and controls in the ability to generate responsive cell lines. This translated to a frequency of responsive cells of 0-4 per 10(7) peripheral blood mononuclear cells (PBMC) in normal individuals and 0-200 per 10(7) PBMC in patients. This novel technique may provide a means of determining the number of responsive cells to specific autoantigens in the peripheral blood of patients and the ability to follow the response over time.

Effects of protease inhibitors on the course of CMV retinitis in relation to CD4+ lymphocyte responses in HIV+ patients

AIM

To gain insight into the course of CMV retinitis (CMVR) in AIDS patients receiving protease inhibitors (PI), and to evaluate whether certain patterns of CD4 response are indicative of the clinical outcome and the risk of recurrence.

METHODS

15 consecutive AIDS patients receiving maintenance therapy for CMVR were included in a prospective observational cohort study at the university hospital between July and October 1996. Patients were evaluated for signs of CMVR activity and intraocular inflammation. CMVR recurrence was defined as the primary clinical endpoint. Follow up was performed until July 1997. No patient was lost to follow up. Clinical outcome was related to CD4+ lymphocyte counts, which were monitored every 6 weeks. Highly active antiretroviral treatment regimen including PI was started at study entry.

RESULTS

All recurrences (n = 7) were in patients who failed to have a sustained increase in CD4 counts, whereas CMVR remained inactive during a follow up of 42-52 weeks in those who were able permanently to restore their CD4 values to 100 x 10(6)/l or more (n = 5). The remaining three patients died after 12, 16, and 50 weeks, respectively, without recurrences. All relapses of CMVR were seen after 6-16 weeks, and at CD4 counts well below 100 x 10(6)/l.

CONCLUSIONS

The beneficial effects of PI treatment correlate with the pattern of CD4 response. Sustained increases in CD4 counts achieved in the first 16 weeks of treatment are associated with a prolonged period of CMVR quiescence. Poor initial response is associated with a high risk of CMVR recurrence.

Optic neuritis heralding varicella zoster virus retinitis in a patient with acquired immunodeficiency syndrome

We report on a 29-year-old severely compromised acquired immunodeficiency syndrome patient who developed retrobulbar optic neuritis 5 weeks after an episode of cutaneous herpes zoster infection. During the optic neuritis, varicella zoster virus could be demonstrated in the cerebrospinal fluid. The neuritis responded well to treatment with foscarnet, but, 3 weeks into therapy, varicella zoster retinitis developed. Additional treatment with intravenous acyclovir stopped progression of the retinitis and resulted in healing of the retinal lesions. This case suggests that retrobulbar optic neuritis can be regarded as a prodrome of imminent acute retinal necrosis. Early recognition and prompt therapy with combined antivirals may prevent the development of this devastating ocular complication of varicella zoster infection.

Use of topical FK506 in a corneal graft rejection model in Lewis rats

PURPOSE

To evaluate the immunosuppressive effect of topical FK506 on allograft corneal rejection in rats.

METHODS

Lewis rats were used as recipients and Fisher rats as corneal graft donors. In Experiment 1, all rats received intraperitoneally FK506 (0.3 mg/kg per day) for 7 days to ensure equal baseline parameters. The rats then were assigned randomly to treatment with topical 0.3% FK506 or vehicle alone. In another set of experiments, rats were treated only with topical treatment. The grafts were inspected by clinical evaluation. Corneas obtained at the time of maximum rejection were used for histology and immunohistochemistry.

RESULTS

The selected combination of rat strains caused 100% graft rejection in untreated animals within 2 weeks after the penetrating keratoplasty. In the treated animals, rejection was delayed until the end of topical therapy. One third of corneal grafts remained clear until day 30. Histologic and immunohistochemical studies confirmed the clinical evaluations. Untreated rat corneas had a large number of infiltrating helper-inducer T cells, macrophages, interleukin-2 receptor-expressing cells, and Ia-antigen-expressing cells. At the same timepoint, topically treated corneas showed a limited inflammatory response characterized by a 2/3 reduction in the number of infiltrating helper and cytotoxic cells, and a five-fold decrease in the expression of class I and class II major histocompatibility antigens.

CONCLUSIONS

Topical FK506 treatment is an effective way of preventing corneal graft rejection in the Lewis rat corneal graft model. It shows promise as a drug to prevent corneal graft rejection in humans.

Long-term follow-up of patients with chronic uveitis affecting the posterior pole treated with combination cyclosporine and ketoconazole

PURPOSE

Combined treatment with cyclosporine (CsA) and ketoconazole in autoimmune diseases has received little attention. This article reports the outcome of a pilot study in patients receiving combination therapy for chronic uveitis affecting the posterior pole.

METHODS

Six patients initially treated with CsA and oral prednisone were observed prospectively on a combination of CsA, prednisone, and ketoconazole. Data were analyzed for visual acuity, number of flare-ups, and signs of systemic toxicity.

RESULTS

Patients were treated with CsA for a mean of 13 months and CsA-ketoconazole for a mean of 33 months. Although patients had a number of flare-ups before combination therapy, only two flare-ups in two patients were noted during combined therapy (P = 0.055). Three patients showed signs of renal toxicity on CsA, and two continued to show signs of toxicity on CsA-ketoconazone. One patient stabilized and maintained normal renal parameters. Using CsA, three of six patients showed elevations of systolic and diastolic pressure. After switching to CsA-ketoconazole, the patient's systolic pressure remained unchanged, and the diastolic pressure returned to normal in all patients (P = 0.03). No toxicity related to ketoconazole alone was observed.

CONCLUSION

A combination of CsA and ketoconazole is effective in the treatment of chronic uveitis affecting the posterior pole. It appears to be more effective in preventing recurrences than does CsA alone and does not lead to an increased risk of renal toxicity.

Intraocular levels of methotrexate after intravenous administration

PURPOSE

To determine if adequate intraocular levels of methotrexate are achieved after intravenous administration.

METHODS

After intravenous administration, methotrexate levels were determined in the serum, the anterior chamber, and the cerebrospinal fluids of a patient with recurrent ocular lymphoma. A fluorescence polarization immunoassay was used to make the determinations.

RESULTS

At seven hours into a 24-hour intravenous infusion, methotrexate was at cytotoxic level in all samples. At 74 hours, cytotoxic levels were present only in the aqueous humor.

CONCLUSION

Sustained cytotoxic ocular methotrexate levels are achievable after systemic administration.

Intraocular inflammatory disease (uveitis) and the use of oral tolerance: a status report

Intraocular inflammatory disease, or uveitis, is a disorder that mostly affects children and young adults. It is the cause of about 10% of the severe visual handicap in the United States. Many of the severe, sight-threatening uveitic conditions are thought to be driven by putative autoimmune mechanisms, often with high-dose oral prednisone use as treatment, along with cytotoxic agents, antimetabolites, and cyclosporine adjunctively. The feeding of the uveitogenic retinal S-Ag to rats immunized with the same antigen resulted in clinical protection. A pilot study in which two patients, one with pars planitis and the other with Behcet's disease, were fed with the retinal S-Ag resulted in these patients' immunosuppressive medication being decreased and/or stopped. The trial also provided us with information concerning dosage and expected immune responses. A randomized, masked study looking at the effect of feeding retinal antigens to uveitis patients is ongoing.

Characterization of human B cell proteins binding specifically to uveitopathogenic peptide 1169-1191 of bovine IRBP

Peptide 1169-1191 is a major uveitopathogenic determinant of bovine Interphotoreceptor Retinoid Binding Protein (IRBP) in Lewis rats. Previously, we identified two proteins with approximate molecular masses of 72 and 74 kDa and one with a molecular mass of 40 kDa from B cells of naive Lewis rats and EBV-transformed B cells from a human patient with ocular Behçet's disease that bind to bovine IRBP peptide 1169-1191. In this study, we have partially characterized these proteins. The two proteins with molecular masses 72 and 74 kDa belong to the HSP 70 family of proteins and the 40-kDa protein is actin.

Identification of heat shock proteins binding to an immunodominant uveitopathogenic peptide of IRBP

Intracellular binding proteins have been identified and isolated from B cells by their ability to bind to the synthetic peptide (1169-1191), the major immunodominant epitope of bovine interphotoreceptor retinoid-binding protein (IRBP) coupled to cyanogen bromide activated Sepharose 4B. After SDS-PAGE, two discrete protein bands of approximately 72 and 74 kDa, were found to be present in B cells of naive Lewis rats as well as in EBV transformed B cells from a human patient with ocular Behçet's disease. Enhanced expression of these peptide-binding proteins was achieved by incubating the cells with Lipopolysaccharide (LPS) from S. typhimurium. The approximately 72 and 74 kDa peptide-binding proteins reacted in western blot with monoclonal antibodies specific for both constitutively expressed and inducible 72/74 kDa hsp 70 proteins. The demonstration that these proteins bind to the immunodominant epitope of IRBP indicates that they may play a role in the processing and presentation of antigens by antigen-presenting cell (APC).

Human S-antigen: presence of multiple immunogenic and immunopathogenic sites in the Lewis rat

To identify the immunogenic and immunopathogenic sites present in human S-Antigen (S-Ag), 40 overlapping peptides that span the whole length of the S-Ag molecule were synthesized and tested in the Lewis rat model of experimental autoimmune uveitis. The most pathogenic sequences were 180-200, 340-360 and 350-370. Ten peptide sequences were identified that induced visible inflammation in the eye. A total of 23 peptides gave an in-vitro proliferative response following immunization in animals. The ability to generate an immune response was not linked to the pathogenic capacity of the sequence. The most pathogenic sequence, 340-360, was only weakly proliferative. Peptide 180-200 and peptide 340-360 gave higher T-cell proliferative responses, but these were lower than the maximal proliferative response observed with non-pathogenic sequences. In animals immunized with whole S-Ag, the majority of the determinants did not elicit a proliferative response, indicating that in S-Ag, the majority of the immunogenic determinants are cryptic and are not presented by the APC located in the lymph nodes.

Intraocular lymphoma. Clinical and histopathologic diagnosis

BACKGROUND

Intraocular lymphoma is associated with significant morbidity and mortality, but early diagnosis and treatment may improve prognosis.

METHODS

The diagnostic features of 12 cases of intraocular lymphoma diagnosed at the National Eye Institute between 1984 and 1992 were retrospectively reviewed.

RESULTS

A pathologic diagnosis of large B-cell lymphoma was made on vitrectomy specimens in ten patients, cerebral spinal fluid in one, and on an enucleation specimen in one. The mean time from onset of symptoms to diagnosis was 21.4 months (range, 1-66 months). All 12 patients were given a final diagnosis of non-Hodgkin's lymphoma of the central nervous system (NHL-CNS), based on the epidemiology, pathology, and clinical course of their tumors. Although an initial vitrectomy was negative for malignant cells in three of ten patients, a repeat vitrectomy specimen subsequently showed intraocular lymphoma. Results of examination of the cerebrospinal fluid (CSF) showed malignant cells in 5 of 11 patients, although malignant cells were only identified after repeat examination of additional samples of CSF in three of these patients. Malignant cells often are difficult to identify, and an experienced cytopathologist was critical in making the correct diagnosis. In addition, corticosteroids are lympholytic to the lymphoma cells, and they appeared to decrease the viability of tumor cells obtained in samples of vitreous and CSF.

CONCLUSION

The prompt, appropriate handling of specimens and review by an experienced cytopathologist are critical to the diagnosis of intraocular lymphoma. Malignant cells often are present in the cerebral spinal fluid at the time that ocular lymphoma is diagnosed. Nevertheless, multiple vitrectomies and lumbar punctures may be necessary before the correct diagnosis is made.

A masked, randomized, dose-response study between cyclosporine A and G in the treatment of sight-threatening uveitis of noninfectious origin

Thirty-two patients with sight-threatening uveitis and a decrease in visual acuity requiring systemic therapy were randomly assigned to either cyclosporine A or G in a dose-escalation study. Groups received from 2.5 mg/kg of body weight/day to 10 mg/kg of body weight/day of either drug along with low-dose prednisone. More patients taking cyclosporine G had improved visual acuity and a decrease in macular edema, which occurred more rapidly than in the other group, even at the lower doses tested. No difference in renal function was noted between groups at any doses tested. Four patients receiving cyclosporine G had hepatic alterations, but only one required cessation of the drug. The study indicates the potential usefulness of cyclosporine G, particularly at lower doses (4 mg/kg of body weight/day), which could lower the potential for serious renal complications.

The role of chorioretinal biopsy in the management of posterior uveitis

BACKGROUND

The ideal management of intraocular inflammation may require a tissue diagnosis. Diagnostic vitrectomy is a well-established method for acquiring such tissue. However, in some patients, the diagnostic pathology is limited to the choroid and retina and vitrectomy may yield no useful information. In such cases, a more aggressive surgical approach to obtain tissue may be useful.

METHODS

The authors performed chorioretinal biopsies on seven patients with progressive chorioretinal lesions of unknown etiology. Indications for biopsy included: (1) macular-threatening lesions unresponsive to therapy, (2) suspicion of malignancy, or (3) suspicion of an infectious etiology. In all cases, it was expected that the results would alter therapy or other aspects of clinical care. Preoperative visual acuity was 20/200 or worse in each eye biopsied with one or more peripheral chorioretinal lesions present. Biopsy specimens were divided into three parts and submitted for light and electron microscopy, immunohistochemistry, and tissue culture.

RESULTS

On the basis of the biopsy findings, a diagnosis of multifocal choroiditis and subretinal fibrosis was rendered in three eyes, sarcoidosis in two eyes, and viral retinitis in two eyes. Therapy was changed in five patients. Final visual acuity was unchanged or improved in five eyes. Complications included the progression of lens opacity in all eyes and the development of phthisis in one eye that was extensively diseased preoperatively.

CONCLUSION

Chorioretinal biopsy may provide useful information for determining the diagnosis and guiding the subsequent management of patients with progressive chorioretinal lesions of unknown etiology.

Treatment of autoimmune uveoretinitis in the rat with rapamycin, an inhibitor of lymphocyte growth factor signal transduction

Rapamycin (RAPA) is a macrolide antibiotic with unique immunosuppressive properties. RAPA inhibits T-cell function by interfering with IL-2 and IL-4 signal transduction. It does not prevent IL-2 production or IL-2R expression. The efficacy of RAPA in the treatment of autoimmune diseases was evaluated using the experimental autoimmune uveoretinitis (EAU) model. EAU was actively induced in Lewis rats by immunization with S-antigen in Hunter's adjuvant. RAPA and control vehicle were administered by continuous intravenous infusion over a 14 day period by miniosmotic pump. RAPA treatment initiated on the day of immunization or 7 days later was found to efficiently inhibit EAU induction. The minimal effective dose was 0.1 mg/kg/d. EAU inhibition was correlated with reduced number of cells in the immunization site draining lymph nodes, as well as with a shift and lowering of the peak of the lymphocyte proliferative response curve. The anti-S-antigen antibody response was delayed by 3 days under RAPA treatment and the serum levels lowered in a dose dependent manner. An initial body weight loss was observed during the first week of drug administration, but there was a normal weight gain afterward.