Interferon-gamma release assay as a diagnostic test for tuberculosis-associated uveitis.

BACKGROUND: To study the use of interferon-gamma release assay (IFN-γ) (IGRAs) as a diagnostic test for tuberculosis (TB)-associated uveitis (TAU). DESIGN: Prospective cohort study. PARTICIPANTS: Consecutive new patients (n=162) with clinical ocular signs suggestive of TAU, seen >1 year period at a single tertiary center. METHODS: All subjects underwent investigations to rule out underlying disease, including T-SPOT.TB and tuberculin skin test (TST). Twenty-one subjects with underlying disease and three with interdeterminate T-SPOT.TB results were excluded. Those with T-SPOT.TB- or TST-positive results were referred to infectious diseases physician for evaluation. Anti-TB therapy (ATT) was prescribed if required. Patients' treatment response and recurrence were monitored for six months after completion of ATT, if given; or 1 year if no ATT was given. MAIN OUTCOME MEASURE: Diagnosis of TAU. RESULTS: Mean age of study cohort (n=138) was 46.8 ± 15.3 years. Majority were Chinese (n=80, 58.0%) and female (n=75, 54.3%). TST was more sensitive than T-SPOT.TB (72.0% vs 36.0%); but T-SPOT.TB was more specific (75.0% vs 51.1%) for diagnosing TAU. Patients with either a T-SPOT.TB (1.44; 95% confidence intervals (CI), 0.86-2.42) or TST (1.47; 95% CI, 1.12-1.94)-positive result are more likely to have TAU. The accuracy of diagnosing TAU increases when both tests are used in combination (area under the receiver operator curve=0.665; 95% CI, 0.533-0.795). Patients with both tests positive are 2.16 (95% CI, 1.23-3.80) times more likely to have TAU. Negative T-SPOT.TB or TST results do not exclude TAU (negative likelihood ratios <1.0). CONCLUSIONS: We recommend using a combination of clinical signs, IGRA, and TST to diagnose TAU.

Cytomegalovirus anterior uveitis: outcome of treatment.

AIM: To determine the outcome of antiviral treatment of cytomegalovirus (CMV) anterior uveitis. METHODS: A retrospective review of patients from Singapore National Eye Centre with CMV anterior uveitis diagnosed by aqueous polymerase chain reaction. Ganciclovir treatment consisted of systemic, topical, intravitreal injections or intravitreal implant. The main outcome measure was resolution of anterior chamber inflammation. RESULTS: 72 eyes of 70 patients were positive for CMV DNA. 35 eyes were treated (23 eyes with acute recurrent anterior uveitis and 12 eyes with chronic anterior uveitis). Eyes that did not respond or recurred with one treatment may receive another course of treatment. There were 47 treatment episodes, 36 (76.6%) of which resulted in a response. However, there were 27 (75.0%) episodes of recurrences after stopping treatment. Systemic and intravitreal ganciclovir and ganciclovir implant had good response rates but also had very high recurrence rates. Ganciclovir gel had moderate response rates, but its recurrence rates were also lower than those of the other modalities. CONCLUSIONS: Ganciclovir gel had lower recurrence rates than the systemic ganciclovir and the implant and should be considered as an option for treatment of CMV anterior uveitis.

Syphilitic uveitis: an Asian perspective.

AIM: To examine the clinical manifestations of syphilitic uveitis in a population and review trends in incidence at a tertiary referral centre. METHODS: A retrospective, non-comparative interventional case series of 22 consecutive patients with syphilitic uveitis who were managed in the Ocular Inflammation and Immunology Services of the Singapore National Eye Centre between 1995 and 2006. RESULTS: Twenty-two patients (mean age 52.7 years, range 18-78) with a positive serum fluorescent treponemal antibody absorption test (100%) and negative HIV serology were reviewed. Non-granulomatous anterior uveitis was the commonest presenting finding (18/29 eyes, 62.06%). Posterior uveitis was seen in four (13.7%), intermediate uveitis in three (10.3%) and panuveitis was seen in eight (27.5%) eyes at presentation. Vitritis (19 eyes, 65.4%) was the commonest posterior segment finding. The majority (86.4%) had latent syphilis at the time of ocular involvement. An increasing trend in the number of cases of ocular syphilis in the past decade was not observed. CONCLUSIONS: Despite resurgence in infectious syphilis, this centre did not see a dramatic rise in cases of syphilitic uveitis. Ocular syphilis presented most frequently as a non-granulomatous inflammation. Therefore, syphilis serology should be sought even for cases of anterior uveitis.

Risk factors for endogenous Klebsiella endophthalmitis in patients with Klebsiella bacteraemia: a case-control study.

AIM: To identify risk factors for Klebsiella endophthalmitis in patients with Klebsiella sepsis. METHODS: This is a retrospective case-control study. The study population consisted of all patients with positive blood cultures for Klebsiella, admitted to Changi General Hospital (Singapore) from August 2004 to July 2005. The cases were patients who developed Klebsiella endophthalmitis, and the controls were those who did not. The potential risk factors analysed included age, sex, race and total white cell count at presentation, maximum temperature response, co-morbid pathologies, presence of severe infection, site of primary infection, antibiotic sensitivity of the bacterial strain, and systemic antibiotics treatment regimen. RESULTS: 133 consecutive patients with Klebsiella bacteraemia confirmed by blood culture were included. Five (3.8%) developed endophthalmitis. Klebsiella endophthalmitis was significantly associated with liver abscess as the primary site of infection (p<0.001) and disseminated intravascular coagulation (p = 0.010) on both univariate and multivariate analysis. Diabetes mellitus and other co-morbid pathologies, race and maximum temperature response were not risk factors for the occurrence of endophthalmitis. CONCLUSIONS: Liver abscess and disseminated intravascular coagulation are risk factors for endogenous endophthalmitis in patients with Klebsiella sepsis.

Subconjunctival injection of triamcinolone in the treatment of lid retraction of patients with thyroid eye disease: a case series.

PURPOSE: To report the results of subconjunctival injection of triamcinolone in the treatment of thyroid eye disease-related lid retraction. INTERVENTION: Patients with either unilateral or bilateral upper lid retraction, secondary to thyroid eye disease, diagnosed during the period of February 2004 to June 2005 were recruited. An injection of 0.5 ml of triamcinolone acetonide (40 mg/ml kenalog) with 0.1 ml of 2% lignocaine was injected into the subconjunctival region of the lid between the conjunctiva and Muller's muscle under topical anaesthesia on upper lid eversion. Pre- and post-procedure measurements included lid aperture, marginal reflex distance, the amount of lagophthalmos, and intraocular pressure measurements. Photographs were also obtained before the procedure and at subsequent visits. Follow-up was done at 2 weeks, 1, 3, 6 months and at 1 year. RESULTS: Three of the four patients had resolution of their upper lid retraction within 1 month of treatment, with one patient requiring a repeat triamcinolone injection. The patient who had fibrotic muscles did not respond to triamcinolone injections and required surgical correction. CONCLUSION: Upper lid subconjunctival triamcinolone appears to be an effective treatment option in reducing lid retraction in patients with recent onset of thyroid eye disease.

Correlation between peripapillary atrophy and corticosteroid therapy in patients with Vogt-Koyanagi-Harada disease.

AIMS: To determine the correlation between systemic corticosteroid therapy and the occurrence and size of peripapillary atrophy (PPA) in patients with Vogt-Koyanagi-Harada (VKH) disease. METHODS: All patients with VKH disease were retrospectively reviewed for their corticosteroid regimen. The extent of the PPA, if present, was measured using digitized imaging software, by two masked observers. Eyes with myopia greater than 6 dioptres or glaucoma were excluded. The patients were classified into three groups: early high (EH), late high (LH), and low dose (LD), according to the dose and timing of corticosteroids received during the acute phase of the disease. RESULTS: There were 40 eyes in the EH group, 25 eyes in the LH group, and 23 eyes in the LD group. Multivariate analysis showed that corticosteroid therapy was the main determinant of PPA occurrence. All the eyes in the LD group had PPA and eyes in the LH groups were 4.02 times (95% confidence interval 1.24-13.07) more likely to develop PPA than those in the EH group. The LD group also had larger PPA to disc ratios than the EH group. (Mean of 2.83 vs0.19, P<0.001). CONCLUSION: The development and extent of PPA in patients with VKH disease appear to be dependent on the dose and timing of systemic corticosteroids.

Visual disturbances in dengue fever: an answer at last?

Visual disturbances in dengue infection are uncommon but may result in permanent visual impairment. We report a 32-year-old Chinese woman with dengue infection and she developed retinal haemorrhage, retinal vasculitis and macular detachment. Autoimmune screen revealed a low C4 complement level, possibly due to partial C4 complement deficiency. The patient was treated with steroids and there was significant improvement in her vision. Partial C4 deficiency predisposes to autoimmune disease, and patients with pre-existing low C4 levels may be susceptible to ocular complications in dengue infection. Interestingly, previous case reports of ophthalmic complications of dengue infection occurred in young female patients, who are likewise predisposed to autoimmune disease. In conclusion, in individuals predisposed to autoimmune disease (females and patients with partial C4 deficiency), dengue infection may provide the antigenic trigger for immune complex deposition and retinal vasculitis. Steroids may have an important role in the treatment of this condition.

Practice preferences of ophthalmic anaesthesia for cataract surgery in Singapore.

INTRODUCTION: This study aims to describe the preferences of ophthalmic anaesthesia for cataract extraction among ophthalmologists in Singapore. METHODS: A nationwide questionnaire survey of all cataract surgeons in institutional and private practice in Singapore was conducted in August 2004. RESULTS: The response rate was 61.1 percent (88 out of 144 eligible ophthalmologists surveyed). Phacoemulsification was the preferred surgical technique for 92 percent of the respondents while extra-capsular cataract extraction was preferred by eight percent. For all surgeons performing phacoemulsification, the anaesthesia technique of choice was peribulbar anaesthesia for 43 percent, topical anaesthesia for 42 percent, retrobulbar anaesthesia for 13 percent, and sub-tenons and general anaesthesia for one percent each of the respondents. For all the surgeons performing extra-capsular cataract extraction, the preferred anaesthetic technique was peribulbar anaesthesia for 69 percent, retrobulbar anaesthesia for 30 percent and sub-tenons anaesthesia for one percent of the respondents. The surgeons' main reasons for choosing a specific anaesthesia modality for their surgery were patient comfort and surgeon's choice. The majority of surgeons used mild sedation and monitored anaesthesia care for their cataract surgeries. CONCLUSION: Peribulbar anaesthesia is currently the preferred anaesthesia technique for both phacoemulsification and extra-capsular cataract extraction in Singapore. Topical anaesthesia closely follows peribulbar anaesthesia as a preferred choice for phacoemulsification.

Pseudoretinoblastoma in enucleated eyes of Asian patients.

INTRODUCTION: Retinoblastomas of the eye are a cause of childhood blindness and have a high rate of mortality, as well as a hereditary mode of transmission. Other conditions that mimic retinoblastomas are known as pseudoretinoblastomas, and are managed differently. Although pseudoretinoblastoma and the accuracy of retinoblastoma diagnosis have been reviewed in Caucasian patients, published studies in Asian patients are lacking. The purpose of this article is to report our experience with pseudoretinoblastomas in two major ophthalmological centres in Asia. METHODS: A case series of 28 enucleations carried out for suspected retinoblastoma at the Singapore National Eye Centre and KK Women's and Children's Hospital, Singapore, between January 1991 and December 2002, is reported. All cases were subjected to a detailed history from parents, followed by external ocular examination, slit-lamp biomicroscopy and binocular indirect ophthalmoscopy. Ancillary studies, such as B-scan ultrasonography and computed tomography, were employed as necessary to confirm the diagnosis. Histology was obtained on all cases. RESULTS: Of the 28 cases, 25 (89 percent) were found on histological analysis to be retinoblastomas. Three (11 percent) were pseudoretinoblastomas. There were two cases of Coat's disease and a case of presumed ocular toxocariasis. These three cases were described in detail. CONCLUSION: Although our sample size is small, the percentage of confirmed retinoblastomas was found to be only slightly higher than that found in western countries. Our findings are consistent with their findings that Coat's disease and presumed ocular toxocariasis are the more common causes of pseudoretinoblastoma.

Multifocal venous malformations: two interesting case presentations.

INTRODUCTION: Multiple venous abnormalities involving the orbit, head and neck regions have been previously described. We present two similar cases of low-flow orbital venous vascular malformations (VVMs) in association with multiple low-flow VVMs in the head and neck as well as in the peripheral limb. Literature search revealed that this association has not been previously reported. METHODS: Retrospective review of two patients with multifocal VVMs was performed. RESULTS: Case 1: A 46 year-old Chinese female had a history of multiple vascular lesions involving the right orbit, the tongue, right neck region, right arm and one finger. Valsalva manoeuvre resulted in distension of these lesions. CT scan of the orbits demonstrated bilateral low-flow VVMs. CT angiogram also revealed multiple developmental venous anomalies in the brain. Case 2: A 16 year-old Chinese female had a history of multiple venous malformations involving the neck, left forearm and oral region. Dynamic manoeuvres demonstrated the distensible nature of these lesions. MRI scans of the orbits showed bilateral extraconal low-flow VVMs. Similar mass lesions were seen on MRI scans of the neck. CONCLUSIONS: Multiple cervicofacial venous malformations with developmental abnormalities of the intracranial venous system have been described previously. However, their associations with similar VVMs in the peripheral limb regions have not been reported. Our cases illustrate this rare association. VVMs appear to be benign in nature with symptoms mainly due to mass effect. Management can be conservative in the absence of any sight threatening complication.

Integrated hydroxyapatite implant and non-integrated implants in enucleated Asian patients.

INTRODUCTION: This study compares the outcome and complications of integrated hydroxyapatite implant and non-integrated orbital implants following enucleation in Asian patients. MATERIALS AND METHODS: This is a retrospective study of enucleated patients with coralline hydroxyapatite implants versus non-integrated implants (acrylic, glass and silicone) at the Singapore National Eye Centre from January 1991 to December 2000. The outcomes measured were implant migration, extrusion, socket infection, conjunctival dehiscence and implant exposure. Statistical analysis was done using the 2-sample t-test. RESULTS: Twenty-one patients had the hydroxyapatite implant and 38 non-integrated implants (27 acrylic, 9 glass and 2 silicone). The mean duration of follow-up was 2.7 years and 4 years for the hydroxyapatite implant and non-integrated implants respectively. Three patients with pre-existing severe socket contracture before enucleation surgeries were excluded from the study. Four cases of implant migration, 4 cases of implant extrusion and 3 cases of socket infection were encountered; all were sockets fitted with non-integrated implants. There was a higher rate of conjunctival dehiscence for sockets with hydroxyapatite implants (6 out of 21) compared to sockets with non-integrated implants (3 out of 35). This was statistically significant (P = 0.048). CONCLUSIONS: Implant complications of migration, extrusion and socket infection were found in non-integrated implants and none in coralline hydroxyapatite implants, which had a significantly higher rate of conjunctival dehiscence. Most of these were easily managed with only a small number progressing to implant exposure.