PubMed Health⌕ Search

Biomedical subjects

Wee-Kiak Lim

Publications and source records attributed to Wee-Kiak Lim.

14 recordsLinked to original sources

Optic nerve toxoplasmosis and orbital inflammation as initial presentation of AIDS.

PURPOSE: To report a case of toxoplasmosis with optic nerve and orbital involvement as the initial presentation of HIV infection. METHOD: Case report. RESULTS: A 46-year-old zookeeper, who had had right central retinal vein occlusion (CRVO) 2 weeks previously, presented with painless lid and conjunctival swelling and profound visual loss in his right eye (RE). Examination revealed no light perception (NLP) RE with axial proptosis and ocular motility restriction; fundal examination revealed a clinical picture of an ischaemic CRVO. MRI of the brain and orbit showed ring-enhancing targetoid lesions in the brain and inflammatory changes in the right optic nerve, extraocular muscles and orbital fat. He was subsequently found to be HIV positive and had positive toxoplasma IgG serology. CONCLUSIONS: Immunocompromised individuals have an increased likelihood for more severe and atypical presentations; this highlights the need for increased index of suspicion for HIV infection as ocular or orbital disease may be the first manifestation of life-threatening systemic toxoplasmosis.

AIDS-Related Opportunistic Infections↗

Concurrent intermediate uveitis and an enhancing intracranial lesion as the initial manifestation of sarcoidosis.

INTRODUCTION: Posterior segment involvement has been described to be associated with central nervous system involvement in sarcoidosis as a result of direct sarcoid tissue infiltration or mass effect of a cerebral lesion. However, isolated intermediate uveitis occurring concurrently with central nervous system involvement prior to extensive systemic disease is rare. CLINICAL PICTURE: We describe a patient with neuro-ophthalmic manifestations of intermediate uveitis and an enhancing basal ganglia lesion at initial presentation, in the absence of extensive systemic disease. TREATMENT: He was treated with high-dose systemic steroids which was progressively tailed down over 6 months. OUTCOME: There was prompt resolution of vitritis with good preservation of visual acuity. CONCLUSION: The difficulties of the initial diagnosis of sarcoidosis and the indications for initiation of steroid therapy are illustrated. We use this case to emphasise the need for a high clinical suspicion of sarcoidosis in the presence of similar unusual and seemingly unrelated combinations of neurological manifestations so as to facilitate the prompt institution of appropriate treatment when indicated.

Adult↗

Visual function in Vogt-Koyanagi-Harada patients.

BACKGROUND: Vogt-Koyanagi-Harada (VKH) disease presents with anterior segment inflammation, choroiditis and exudative retinal detachment. Following resolution of the inflammation, VKH patients have been noted to complain of visual disturbances despite good visual acuity. We therefore investigated the visual function deficits of convalescent VKH patients. METHODS: A cross-sectional observational nonrandomized controlled study of convalescent VKH patients from the Uveitis Service of the Singapore National Eye Centre, and normal subjects was performed. The best-corrected visual acuities (BCVA) and multifocal electroretinograms (mfERGs) of VKH patients with and without peripapillary atrophy (PPA) were compared with those of the normal eyes. The mfERG results were subdivided into those obtained from the peripapillary area and those from the rest of the macular. RESULTS: Eleven VKH eyes with large PPA to disc ratios (PPA/D ratio >2), 15 VKH eyes with PPA/D ratios<1 and 6 normal eyes were included in the study. Five eyes (54.5%) of VKH patients with PPA/D>2 had a BCVA of less than 20/40. All the other eyes had 20/20 vision. Nine of the 11 VKH eyes with PPA/D>2 also had large areas of chorioretinal atrophy. The mfERG responses of VKH eyes with PPA/D ratio >2 were markedly reduced in amplitude (p<0.001) and delayed in implicit time (p<0.001) throughout the entire macular area. VKH patients with PPA/D ratio<1 had significantly reduced mfERG amplitudes throughout the entire macular area, as well as delayed implicit times at the peripapillary region (p=0.026). Sub-division of VKH eyes with PPA/D<1 into eyes with no PPA and eyes with a small PPA, showed that both groups had a similar reduction in response amplitude over the entire macular region. However, the implicit time was significantly delayed in eyes with small PPA when compared to those without PPA (p<0.03). CONCLUSIONS: VKH patients with large PPA have clinically significant visual dysfunction. VKH patients without PPA also have subclinical retinal dysfunction. The mfERG may be a useful adjunct in the management of VKH by detecting early retinal damage.

Cross-Sectional Studies↗

Progression of varicella-zoster virus necrotizing retinopathy in an HIV-negative patient with transient immune deviation.

PURPOSE: To report a case of unilateral varicella-zoster virus (VZV) necrotizing retinopathy that progressed from outer retinitis with features of progressive outer retinal necrosis (PORN) to typical acute retinal necrosis (ARN) in an HIV-negative patient with a transient decrease in CD4 lymphocyte counts and CD4/CD8 ratio. METHOD: Case report. RESULTS: A 41-year-old Chinese man presenting with blurred vision in the right eye was diagnosed with herpetic necrotizing retinitis without vitritis. Fundus examination revealed retinal arteritis and extensive deep whitish retinal lesions in the mid-periphery with minimal vitritis. Aqueous humor and vitreous PCR were positive for VZV. His CD4 count on presentation was depressed (239 cells/ul) and the CD4/CD8 ratio was low (0.8). The referring ophthalmologist had treated him with prednisolone 60 mg/day. At our institution, when intravenous acyclovir was started and the steroid therapy discontinued, he developed severe vitritis and the deep retinal lesions progressed to full-thickness retinitis typical of ARN. Repeat CD4 count was 512 cells/ul at day 14. In total, he was treated with 14 days of i.v. acyclovir (12 mg/kg 8-hourly) followed by oral valaciclovir 500 mg three times a day for 3 months. Prednisolone 30 mg once daily was restarted and tapered over 3 months. Despite prophylactic argon retinal photocoagulation to the edge of the retinitis, the patient developed a total retinal detachment at 3 months. CONCLUSIONS: VZV retinal infection in an HIV-negative patient with transient immune deviation can manifest initially as outer retinitis with features similar to PORN and progress to typical ARN when CD4 counts return to normal.

Adult↗

Suppression of immune-mediated ocular inflammation in mice by interleukin 1 receptor antagonist administration.

OBJECTIVE: To evaluate the effects of an interleukin 1 receptor antagonist (IL-1RA) on the development of immune-mediated ocular inflammation in mice. METHODS: Recombinant, human, nonglycosylated IL-1RA (anakinra [kineret]) was tested for its inhibitory effects in 2 systems: (1) experimental autoimmune uveitis induced by interphotoreceptor retinoid-binding protein in B10.A mice using routine procedures and evaluated by clinical and histological examination, and (2) ocular inflammation in mice induced by transfer of hen egg lysozyme-specific T cells to hen egg lysozyme-transgenic mice. Treatment with IL-1RA included daily subcutaneous injections of the drug, at 300 and 500 mg/kg, or phosphate-buffered saline as control. RESULTS: Mean +/- SE experimental autoimmune uveitis scores of histological ocular changes of the mice at day 14 postimmunization with interphotoreceptor retinoid-binding protein were 1.5 +/- 0.3 in control mice; 1.0 +/- 0.4 in 300-mg/kg anakinra-treated mice; and 0.5 +/- 0.2 in 500- mg/kg anakinra-treated mice (P = .004). There was a corresponding decrease in the cellular immune response and cytokine production of immune cells in treated mice. Suppression of ocular inflammation by anakinra in the transfer system was also observed (P = .04). CONCLUSION: Human IL-1RA suppresses immune-mediated ocular inflammation in mice, affecting both the afferent and efferent components of the pathogenic immune response.Clinical Relevance Systemic administration of IL-1RA may have clinical application in the management of patients with uveitis.

Adoptive Transfer↗

Bilateral uveitis in a patient with autoimmune lymphoproliferative syndrome.

PURPOSE: We report a case of autoimmune lymphoproliferative syndrome (ALPS) presenting with bilateral uveitis. DESIGN: Observational case report. METHODS: Review of case record, serum and aqueous IL-10 and IL-6 cytokine results, and immunosuppressive treatment of a patient with a mutation in the gene encoding Fas. RESULTS: Control of the intermediate uveitis required sustained doses of topical and periocular corticosteroids as well as systemic cyclosporine. The serum IL-10 level was elevated, as commonly seen in ALPS, but the aqueous IL-10 was not. CONCLUSIONS: Despite a Th2 immune predominance in ALPS, uveitis, a Th1-mediated disease, may still manifest in these patients. The pathogenesis of uveitis in ALPS may differ from that of the systemic disease overall. Long-term follow-up is required for patients with uveitis associated with ALPS.

Aqueous Humor↗

Immunopathology of progressive subretinal fibrosis: a variant of sympathetic ophthalmia.

PURPOSE: We report the immunopathology of progressive subretinal fibrosis, a variant of sympathetic ophthalmia. DESIGN: Brief case report. METHOD: Review of medical record and immunopathology of a chorioretinal biopsy of a 40-year-old man who presented with left total retinal detachment (RD) following multiple vitrectomies in the right eye for RD. Small peripherally retinal holes, snow banks, and inflammatory nodules along the ora serrata were observed during left vitrectomy. Both eyes deteriorated rapidly to blindness with progressive subretinal fibrosis and inflammation over 3 months, and the patient was unresponsive to systemic prednisolone and azathioprine. RESULT: Immunopathology of the chorioretinal biopsy of the right eye revealed aggregates of CD20+ B cells, surrounded by CD3+ T cells. CD68+ macrophages were scattered throughout. CONCLUSION: The rapid clinical course described in this case may be related to the unique immunopathology of rapidly forming peudogerminal centers in the choroids and retina.

Adult↗

Ocular manifestations of dengue fever.

PURPOSE: To evaluate ocular manifestations associated with dengue fever. DESIGN: Retrospective case series and literature review. METHODS: Clinical records of patients with dengue fever who subsequently had ocular symptoms and signs develop were reviewed. The clinical presentation and ocular complications were evaluated. RESULTS: Six patients, 5 females and 1 male, were seen with a sudden decrease in vision 6 to 7 days after the initial manifestations of dengue fever were identified. The diagnosis was confirmed by detection of dengue-specific IgM antibodies (IgM enzyme-linked immunoassay). The presenting best-corrected visual acuity ranged from 20/30 to counting fingers, and ocular involvement was bilateral but asymmetric in 5 cases and unilateral in 1 case. Fundus findings included small, intraretinal, whitish lesions, with localized retinal and retinal pigment epithelium (RPE) disturbance, small dot hemorrhages, and vascular sheathing around the macula and the papillomacular bundle. Fluorescein angiography showed arteriolar focal knobby hyperfluorescence at the macula with mild staining of the vascular walls and leakage at the level of the RPE. All 5 cases that had indocyanine green angiography done showed early diffuse choroidal hyperfluorescence with late silhouetting of the larger choroidal vessels. Five patients received steroid therapy: 1 topical, 2 periocular, and 2 oral. Over 2 to 4 months, RPE discoloration was observed over the affected areas. After the acute episode, 3 patients showed partial recovery of vision, and in the remaining patients, the visual acuity remained stable. CONCLUSIONS: Ocular complications associated with dengue fever are rare but may result in permanent visual impairment.

Adult↗

Retinal detachment in atopic dermatitis can masquerade as acute panuveitis with rapidly progressive cataract.

PURPOSE: To report two cases of retinal detachment in young patients with atopic dermatitis masquerading as acute panuveitis. DESIGN: Retrospective observational clinical case reports. PATIENTS: Patients with atopic dermatitis presenting with acute panuveitis and subsequently diagnosed with retinal detachment at the Singapore National Eye Centre. METHODS: A review of the clinical case records. RESULTS: Two young patients aged 19 and 21 years with a history of atopic dermatitis presented with acute unilateral moderately severe panuveitis. Both developed rapidly progressing cataracts that made detailed visualization of the fundus difficult. Hypotony persisted in one eye despite partial response of uveitis to therapy. The other patient developed ocular hypertension when the vision in the affected eye suddenly deteriorated. Both eyes demonstrated partial response to steroid therapy. The diagnosis of shallow retinal detachment with anteriorly located incriminating retinal breaks was made after partial resolution of vitreous haze in one case and on repeated ultrasonography in the other case. CONCLUSION: A high index of suspicion is required when examining young patients with atopic dermatitis who present with acute panuveitis and a rapidly progressive cataract, which may mask the presence of a shallow retinal detachment.

Acute Disease↗

Microscopic anatomy of the lower eyelid in asians.

PURPOSE: To study the microscopic anatomic relation of the capsulopalpebral fascia, orbital septum, and tarsus of the lower eyelid in Asians. The anatomic differences between the Asian and non-Asian upper eyelid have been well described by various authors, but the differences of the lower eyelid have not been well characterized microscopically. The microscopic anatomy of the lower eyelid in non-Asians was well studied, but in Asians, despite the presence of gross differences, there were very limited studies on the microscopic anatomy. A thorough knowledge of the Asian lower eyelid anatomy is essential for surgical exploration of the eyelid. It may also explain the higher prevalence of eyelid disorders such as epiblepharon and entropion in Asians. METHODS: Ten normal Asian lower eyelids from 10 formalin-fixed cadavers (mean age, 67.5 years) were harvested and studied with light microscopy after staining with Masson trichrome. RESULTS: There was no fusion of the orbital septum and the capsulopalpebral fascia at the lower border of the tarsal plate in 7 specimens and a very limited fusion of these tissues in 3 specimens. The average distance from the inferior tarsal border to the first observable smooth muscle nuclei of the inferior retractors was 1.44 mm. The average tarsal plate thickness was 1.36 mm and the average tarsal plate height was 4.12 mm. CONCLUSIONS: The Asian lower eyelid anatomy differs from its non-Asian counterpart. There was no consistent fusion between the capsulopalpebral fascia and the orbital septum inferior to the inferior tarsal border. No extension of the capsulopalpebral fascia to the skin was observed. The average distance between the inferior retractors and the inferior tarsal plate was 1.44 mm in the normal Asian lower eyelid.

Aged↗

Serpiginous choroiditis.

Serpiginous choroiditis is a rare, usually bilateral, chronic, progressive, recurrent inflammation of the choroid, retinal pigment epithelium, and choriocapillaris of unknown etiology. Based on clinical presentation, it can be classified into 1) peripapillary, 2) macular, and 3) ampiginous types. The clinical course, regardless of the presentation, is progressive with multiple recurrences leading to potentially significant visual loss. Visual outcome is directly related to the involvement of the para-fovea and fovea by the lesions or secondary choroidal neovascularization. The histological findings of the lesions are atrophy of the choriocapillaris, retinal pigment epithelium and photoreceptor cells, and moderate diffuse lymphocytic infiltrates throughout the choroid. Multiple etiologies including autoimmunity, infection, vasculopathy, and degeneration were proposed but none is well supported by clinical and laboratory evidence. Fluorescein and indocyanine green angiography have been useful in the assessment of the extent and the activity of lesions. Due to the insidious and progressive clinical course, an assessment of treatment outcomes needs long term follow-up. Currently, treatment with immunosuppressive and alkylating agents have shown possible efficacy in small case series. Larger clinical studies and interventional trials are required to further our understanding of the pathogenesis, etiology, and for the evaluation of treatment strategies.

Antimetabolites, Antineoplastic↗