Analysis of human herpesvirus 6 U3 gene, which is a positional homolog of human cytomegalovirus UL 24 gene

The US22 gene family was first discovered in human cytomegalovirus (HCMV) and contains several conserved amino acid motifs. Human herpesvirus 6 (HHV-6) also encodes several genes belonging to the US22 family, including the U3 gene (a positional homolog of HCMV UL24). Because the gene products of the US22 gene family function as gene regulators in general, we analyzed the HHV-6A U3 gene. Six transcripts with different molecular weights of 7.5-1.8 kb were detected by Northern blot analysis using a U3-specific probe. Sequence analyses of the respective cDNA clones and primer extension experiments revealed that the U3 gene encoded the 2.0- and 3.5-kb transcripts and had no splicing within the U3 gene region. By immunofluorescence testing using antibodies raised to a fusion protein of MBP (maltose-binding protein) and U3, the U3 viral antigen was detected as early as 24 h p.i. in HHV-6A-infected U373 cells. The antigens were found in cytoplasmic granules, preferentially in the endoplasmic reticulum. Moreover, cotransfection assay using a luciferase gene expression system revealed that the U3 gene product was capable of activating the human immunodeficiency virus long terminal repeat promoter in CV1 cells.

Chorioretinal damage caused by the excision of choroidal neovascularization

PURPOSE

To determine whether choroidal neovascularization excision causes mechanical damage to the neurosensory retina, retinal pigment epithelium, or choriocapillaris.

METHODS

Prospectively, 18 eyes of 18 consecutive patients who underwent choroidal neovascularization excision were observed. Preoperatively and postoperatively, the integrity of the choriocapillaris circulation in the pathway of choroidal neovascularization extraction was studied by fluorescein and indocyanine green angiography. Using static scanning laser ophthalmoscope microperimetry, the presence of iatrogenic scotomas that developed postoperatively in the pathway of choroidal neovascularization extraction was also investigated.

RESULTS

Postoperatively, a choriocapillaris defect was detected in 17 (94.4%) of 18 cases. In 15 cases (83.3%), the choriocapillaris defect had a clear relationship to the pathway of choroidal neovascularization extraction. Postoperatively, a scotoma was present in 16 (88.9%) of 18 cases. In 14 cases (77.8%), the location of the scotoma had a clear relationship to the pathway of choroidal neovascularization extraction.

CONCLUSION

Surgical excision of choroidal neovascularization leads to severe damage of the choroid and retina in the pathway of the extracted choroidal neovascularization. The injury involves the neurosensory retina, retinal pigment epithelium, and choriocapillaris.

Analysis of extracellular matrix synthesis during wound healing of retinal pigment epithelial cells

To investigate changes in retinal pigment epithelial (RPE) cells during wound healing, we evaluated the deposition of newly synthesized extracellular matrix (ECM) over time during wound healing in rat RPE cultures. We also estimated the effect of growth factors on the healing rate and ECM synthesis. After preparing rat RPE cell sheet cultures, we made round 1-mm defects in the cultures. Fibronectin, laminin, and collagen IV synthesis were evaluated with immunocytochemistry every 12 hours after wounding. S-phase cell distribution was analyzed every 12 hours by 5-bromodeoxyuridine uptake. We added either platelet-derived growth factor (PDGF), epidermal growth factor (EGF), or transforming growth factor- beta2 (TGF-beta2) to cultures at concentrations of 1, 10, and 100 ng/mL and immunocytochemically analyzed the effects on ECM and estimated the rate of wound closure. Although approximately 50% closure was achieved 24 hours after wounding, fibronectin deposits first appeared at that time. Laminin and collagen IV were first detected at 36 hours and fibronectin staining had extended toward the wound center. S-phase cells were distributed in concentric rings that moved centripetally over time and corresponded to the leading edge of the area stained with anti-ECM antibodies. TGF-beta2 enhanced ECM deposition, but EGF and PDGF did not. TGF-beta2 decreased the healing rate in a dose-dependent manner, whereas PDGF promoted wound closure. EGF enhanced closure at the highest concentration only. In summary, wound healing in RPE may be initiated when cells at the wound edge slide or migrate toward the wound center, which is followed by cell proliferation and then ECM synthesis. ECM components may be produced in a specific sequence during healing. TGF-beta2 may promote RPE cell differentiation, and PDGF may enhance proliferation during wound healing of the RPE.

Severe corneal dystrophy phenotype caused by homozygous R124H keratoepithelin mutations

PURPOSE

To determine the mutational status of the beta ig-h3 gene in five patients from four Japanese families affected with an unusual, severe form of corneal dystrophy. In these five cases, the corneas were remarkable for confluent round opacities in the superficial stromal layer. The beta ig-h3 gene coding for keratoepithelin was recently identified as the gene responsible for 5q-linked autosomal dominant corneal dystrophies.

METHODS

Genomic DNA was isolated from leukocytes of five patients with the severe form of corneal dystrophy. To screen for point mutations, exons of the beta ig-h3 gene were amplified by polymerase chain reaction and were analyzed with the single-strand conformational polymorphism technique. Subsequently, the mutations were identified by a direct sequencing method and restriction enzyme digestion analysis.

RESULTS

All five patients with the severe form of corneal dystrophy had homozygous R124H keratoepithelin mutations. Histopathologic examinations of the corneas obtained from two patients with the severe form showed granular, rod-shaped deposits.

CONCLUSIONS

The severe phenotype was a pathologic variant of granular corneal dystrophy (GCD). All five patients had homozygous R124H keratoepithelin mutations. The R124H keratoepithelin mutation is the same mutation recently reported to be responsible for Avellino corneal dystrophy. The homozygous R124H keratoepithelin mutations are the cause of the severe variant of GCD characterized by juvenile-onset and confluent superficial opacity.

Photocoagulation and fluid-gas exchange to treat persistent macular holes after prior vitrectomy. A pilot study

OBJECTIVE

This study aimed to determine the efficacy of photocoagulation to the retinal pigment epithelial (RPE) cells and fluid-gas exchange (FGX) in the treatment of persistent macular holes.

DESIGN

A clinical trial.

PARTICIPANTS

Thirteen eyes of 12 patients who had undergone photocoagulation to the RPE and FGX for persistent macular holes after initial vitrectomy and gas tamponade were examined. All eyes had persistent full-thickness macular holes (diameter range, 290-820 microns; 610 +/- 190, mean +/- standard deviation) and no vitreous cortex around the holes on biomicroscopic examination.

INTERVENTION

Argon laser photocoagulation was applied to the RPE in the hole bed, and FGX with 20% sulfur hexafluoride was then performed, followed by 2 weeks with the patient in a prone position. The follow-up period of the patients ranged from 3 to 18 months (10.2 +/- 4.2; mean +/- standard deviation).

MAIN OUTCOME MEASURES

Anatomic success and final visual outcome were measured.

RESULTS

Macular holes were closed successfully after treatment in 12 (92%) of 13 eyes, and visual acuity improved 2 or more lines in 6 eyes (46%). Two eyes (15%) attained visual acuities of 20/40 or better, and seven eyes (54%) attained 20/67 or better visual acuity. There were no intraoperative complications. Cataract formation or progression was recognized during follow-up in five (83%) of six phakic eyes.

CONCLUSIONS

Although this study includes only a small number of patients, it suggests that photocoagulation and FGX can be effective in the treatment of persistent macular holes.

Granular corneal dystrophy with homozygous mutations in the kerato-epithelin gene

PURPOSE

To report a family with several members affected with granular corneal dystrophy Groenouw type 1. Three members of the family were affected with a severe placoid type of corneal dystrophy. To determine the relationship between gene mutations and phenotypic variations of the disease, we analyzed the kerato-epithelin gene.

METHODS

The pedigree included a consanguineous marriage of two affected individuals. The three family members affected with a severe form of corneal dystrophy were offspring of these parents. However, the phenotype of other affected family members was typical granular corneal dystrophy. We isolated genomic DNA from leukocytes of the family members. Exons of the keratoepithelin gene were amplified by the polymerase chain reaction and were analyzed using the single-strand conformation polymorphism technique. Mutations were identified by direct sequencing method and restriction digestion analysis.

RESULTS

The three severely affected family members exhibited homozygous mutations at codon 555 (arginine to tryptophan) in the keratoepithelin gene, whereas those with typical granular corneal dystrophy had the heterozygous mutation at the same codon. Unaffected family members did not have the mutation.

CONCLUSIONS

We determined that the severe phenotype of granular corneal dystrophy is caused by homozygous mutations in the kerato-epithelin gene. Clinical manifestation of the severe phenotype is a placoid type of corneal dystrophy and early recurrence after surgery. Granular corneal dystrophy appears to be the first ophthalmic disease in which homozygosity for a dominant allele has been genetically identified.

[The diagnostic significance of polymerase chain reaction for ocular samples in viral retinitis]

During the past two years we studied the incidence of infection by eight members of the herpesvirus family in ocular samples (tear fluid, the aqueous, and the vitreous) using the polymerase chain reaction (PCR). A total of 31 ocular samples were collected from 22 eyes of 13 patients. The series comprised five cases of acute retinal necrosis, four of cytomegalovirus retinitis, three of proliferative diabetic retinopathy, and one of ocular malignant lymphoma. In 12 eyes of 9 patients with viral retinitis, causative viral DNA was detected either from the tear fluid (1/12, 8%), the aqueous (6/7, 86%), or the vitreous (1/1, 100%). In the fellow eyes free of viral retinitis, no viral DNA was detected in the samples (6 of tear fluid and one of the aqueous). Out of the other 4 patients without viral retinitis, viral DNA was detected in one patient with ocular malignant lymphoma. The findings show that PCR is a useful and sensitive method in the diagnosis of viral retinitis, but that it may give false positive results. The aqueous and the vitreous samples gave more positive results than tear fluid.

Detection and classification of mild irregular astigmatism in patients with good visual acuity

Videokeratography has been available for a decade, and this test is essential for determining the presence and type of irregular corneal astigmatism. Three eyes diagnosed with myopic astigmatism and considered good candidates for refractive surgery with conventional examination were studied. Color-coded maps with videokeratography showed regular astigmatism in one eye and the existence of irregular astigmatism in two eyes. Videokeratography showed that one of these eyes had a keratoconus suspect pattern and the second showed a pattern consistent with pellucid marginal degeneration. Videokeratography can detect and classify irregular astigmatism in cases where routine examination shows no abnormal findings.

Neutrophil chemotaxis induced by corneal epithelial cells after herpes simplex virus type 1 infection

PURPOSE

Neutrophil invasion is a primary event in the development of herpetic keratitis. It has been reported that HSV-1 infection of keratocytes induces the synthesis of IL-8, a potent neutrophil chemoattractant, while corneal epithelium does not. Nevertheless, little is known about the correlation between neutrophil migration and the production of chemotactic factors by HSV-1-infected corneal cells, especially in epithelial cells which form an initial barrier of the ocular surface. We examined whether human corneal epithelial cells as well as keratocytes could induce neutrophil chemotaxis in response to HSV-1 infection.

METHODS

Human corneal epithelial cells immortalized with SV40 (HCE) and human keratocytes were infected with HSV-1. The culture fluids collected at 4, 12, 24 h after infection were assayed for human neutrophil chemotaxis using a modified Boyden chamber method. IL-8 levels in these supernatants were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The chemotactic activity induced by HCE and keratocytes after MP strain of HSV-1 infection peaked as early as 4 h postinfection, then declined. Chemotactic activity induced by HSV-1-infected HCE and IL-8 levels on these supernatants paralleled with the infectious virus titer. It was inhibited by monoclonal anti-IL-8 antibody. UV-inactivation of MP strain abrogated neither the induction of chemotactic activity nor IL-8 secretion of infected HCE.

CONCLUSIONS

At the early phase of HSV-1 infection, corneal epithelial cells play an important role in inducing neutrophil chemotaxis, which was mediated by IL-8.

Scanning laser ophthalmoscope microperimetric assessment in patients with successful laser treatment for juxtafoveal choroidal neovascularization

PURPOSE

To evaluate fixation stability and changes in retinal function in patients with laser scar expansion after successful macular photocoagulation for juxtafoveal choroidal neovascularization (CNV).

METHODS

A consecutive series of 35 patients was examined in this prospective study. Only patients who had been successfully treated with laser photocoagulation for juxtafoveal CNV and who could be followed over a period of at least 6 months were enrolled. Fixation stability and localized light sensitivity were examined by microperimetry using a scanning laser ophthalmoscope. Visual acuity was measured 2 weeks and 3 and 6 months after the laser treatment. The correlation between changes in the logarithm of the minimum angle of resolution (LogMAR) visual acuity and the distance between fixation and the center of the fovea was evaluated.

RESULTS

Of 22 eyes of 20 patients that underwent data analysis, laser scar expansion was observed in 16 (72.7%). Ten (62.5%) of the 16 eyes had relative scotomas corresponding to the expanded laser scars. Mean laser scar expansion ratio was 28.7% in the ARMD group and 109.2% in the myopia group, a statistically significant difference (P < 0.01). The change in LogMAR visual acuity was significantly correlated with the distance of fixation locus from the center of the fovea (r = 0.76).

CONCLUSIONS

Laser scars produced by photocoagulation for juxtafoveal CNV may expand and extend into the fovea, causing secondary retinal dysfunction. Scanning laser ophthalmoscopic assessment may be useful in evaluating fixation stability and subclinical changes in retinal function surrounding the laser scars before visual disturbance appears.

Retinal pigment epithelial lesions associated with choroidal ischemia in preeclampsia

PURPOSE

Retinal and choroidal changes are considered uncommon ocular complications in preeclampsia. The authors evaluated preeclamptic and eclamptic patients to clarify the ophthalmologic features of preeclampsia.

METHODS

The records of 71 women with severe preeclampsia or eclampsia were reviewed. Lesions related to choroidal circulatory disturbance were identified on review of patient fundus examinations and fluorescein angiograms.

RESULTS

Of 31 women whose records were evaluated, serous retinal detachments, yellowish, opaque retinal pigment epithelium (RPE) lesions, or both were present in 47 eyes (both lesions in 29 eyes, RPE lesions alone in 7 eyes, and serous retinal detachments alone in 11 eyes). Of the 36 eyes with RPE lesions, 33 (92%) had solitary or grouped lesions and 3 (8%) had large geographic lesions. The lesions were most commonly observed in the peripapillary area and macula. Lesions resolved without scarring in 3 weeks in 30 (83%) of these eyes. There was residual pigmentary mottling in three eyes (8.5%); in an additional three eyes (8.5%), all of which had had geographic lesions, significant chorioretinal atrophy developed.

CONCLUSIONS

The results suggest that the incidence of RPE lesions and serous retinal detachments, which are transient manifestations of choroidal ischemia, is high in patients with severe preeclampsia and eclampsia. These conditions resulted in significant scarring in only a small number of patients.

Visual function after foveal translocation with scleral shortening in patients with myopic neovascular maculopathy

PURPOSE

To document the visual outcome after successful foveal translocation with intentional retinal detachment and scleral shortening for the treatment of myopic neovascular maculopathy.

METHODS

Two severely myopic patients with subfoveal neovascular membranes underwent surgical translocation of the fovea to an area of healthy retinal pigment epithelium by means of scleral shortening and intentional retinal detachment. In the postoperative period, monocular and binocular visual function were studied.

RESULTS

In one patient, best-corrected visual acuity improved from 20/150 to 20/20 postoperatively. In the second patient, acuity initially improved from 20/70 to 20/30. In both patients, the fixation point shifted from the site of the neovascular membrane. Oblique astigmatism developed and was managed with hard contact lenses. Diplopia and subjective torsion occurred transiently. Micropsia occurred in one patient. Peripheral fusion assessed by Worth four-dot testing after resolution of diplopia disclosed suppression in the nondominant eye in both cases.

CONCLUSIONS

Foveal translocation with intentional retinal detachment and scleral shortening was useful in improving visual acuity in two patients with myopic neovascular maculopathy. Diplopia and aniseikonia occurred but resolved over time as suppression developed. This technique is promising for patients with myopic neovascular maculopathy.

Tractional retinal detachment after branch retinal vein occlusion. Influence of disc neovascularization on the outcome of vitreous surgery

OBJECTIVE

This study aimed to investigate the influence of disc neovascularization on the outcome of vitreous surgery for tractional retinal detachment (TRD) after branch retinal vein occlusion (BRVO).

DESIGN

The study design was a retrospective case series.

PARTICIPANTS

Twenty-two eyes of 22 patients who had undergone vitrectomy for TRD after BRVO at the Osaka National Hospital (Osaka, Japan) or the Surugadai Hospital of Nihon University (Tokyo, Japan) between 1985 and 1995 participated. Seven (32%) of 22 eyes had a TRD secondary to neovascularization of the optic disc (NVD) and neovascularization elsewhere (NVE; group I), and 15 (68%) had a TRD with NVE without NVD (group II).

MAIN OUTCOME MEASURES

Visual acuities and retinal reattachment rates were measured.

RESULTS

Sixteen (73%) of the 22 study eyes showed severe vitreous hemorrhage before surgery, and 11 eyes (50%) had received laser photocoagulation treatment before surgery. Fourteen (64%) of the study eyes achieved total retinal reattachment after initial vitrectomy, and 19 eyes (86%) were reattached completely at final examination. Thirteen eyes (59%) achieved a visual acuity of better than 0.1. Group I patients had a significantly higher rate of recurrent combined traction rhegmatogenous retinal detachment (P = 0.01) and a significantly worse final visual outcome (P = 0.01).

CONCLUSIONS

Better surgical results are expected in eyes without NVD than with NVD among patients who undergo vitrectomy for TRD after BRVO. Although the authors were unable to determine the reason for this difference in the current study, they speculate that the degree of retinal nonperfusion, diffusible angiogenic factors, and distance of the site of occlusion from the disc may each affect visual and anatomic outcomes in these eyes.

Foveal translocation: a comparison of two techniques

Subfoveal choroidal neovascular membrane is a leading cause of legal blindness. Photocoagulation has been effective, but photocoagulation of the fovea causes a decrease in vision immediately after treatment. Surgical removal of the choroidal neovascular membrane is effective for choroidal neovascular membrane in some cases, but it restores useful vision for reading (20/40 or better) in a small number of cases of choroidal neovascular membrane not due to presumed ocular histoplasmosis syndrome. A new treatment for subfoveal choroidal neovascular membrane, foveal translocation, is an innovative procedure in which the fovea is translocated onto healthier retinal pigment epithelium. Three techniques have been developed to relocate the retina, 2 of which (retinotomy and scleral shortening) we performed in 5 cases each. Preliminary results in these 10 cases indicate that foveal translocation provides improvement of visual acuity in 40% of eyes and final visual acuities useful for reading (better than 20/40) in 20% of eyes undergoing translocation with either technique. Further study is essential to refine the amount of translocation needed and to decrease complications of the 2 techniques, including retinal detachment, proliferative vitreoretinopathy, macular pucker, corneal astigmatism, and constricted visual field.

Use of dynamic and colored stereogram to measure stereopsis in strabismic patients

The effectiveness of movement or color has not been well studied in assessing stereopsis in patients with strabismus. We developed a new stereotest equipped with both a monochromatic dynamic random dot stereogram (DRDS) and a static-colored stereogram (SCS) and examined the stereopsis of patients with strabismus. Three-dimensional (3D) images were displayed on a liquid crystal display equipped with a parallax barrier system, allowing 3D images to be seen independently by each eye without glasses. A DRDS with maximum disparity of 3200 seconds of arc was displayed having front-rear movement. An SCS displaying cartoon characters with disparities of 400 seconds of arc was also tested and compared with the Titmus stereotest. A total of 52 strabismic patients were tested. The DRDS showed a significantly higher (P = 0.02) detection rate of stereopsis (39/52, 75%) as compared with the Titmus fly test (28/52, 54%). The SCS did not show any difference in the stereopsis detection rate (24/521, 46%) when compared with the Titmus animal test (20/52, 38%). Thus, the DRDS was useful in detecting stereopsis in patients without stereopsis on the conventional Titmus fly test, while the SCS did not show any difference when compared with the Titmus animal test. The DRDS may examine a different aspect of stereopsis from the static stereopsis measured by the Titmus stereotest or SCS.

Detection of HSV mRNA using reverse transcription-polymerase chain reaction for diagnosis in murine herpetic keratitis model

Reverse transcription polymerase chain reaction (RT-PCR) was applied in the detection of herpes simplex virus-1 (HSV-1) mRNA from tear film and corneal epithelium in a murine herpetic keratitis model. The diagnostic value of this new technique for acute herpetic keratitis was evaluated in comparison with direct PCR for genomic DNA and viral culture. On day 2 postinfection (PI) of HSV, all mice showed dendritic keratitis, and PCR, RT-PCR, and viral culture were positive in all samples. On day 8 PI, no dendritic keratitis was observed in any mouse, PCR was positive in all samples, while RT-PCR was positive in only 5 of 12 samples and viral culture in only 2 of 12. The sensitivity of RT-PCR was lower than that of PCR, and approximately the same as viral culture; however, the findings of RT-PCR more closely concurred with clinical observations than the findings of PCR. These results show the potential of RT-PCR for rapid, specific diagnosis of acute herpetic keratitis.

Using a reference point and videokeratography for intraoperative identification of astigmatism axis

PURPOSE

To estimate the misalignment of the astigmatism axis caused by intraoperative identification of the axis without using reference points.

SETTINGS

Osaka University Medical School, Suita, Japan.

METHODS

This study included 38 eyes of 19 patients with no ocular pathology except refractive error and 32 eyes of 16 patients with cataract. A point was marked on the nasal conjunctiva, on the "intraoperative" horizontal axis as estimated by the examiner using a surgical microscope while the patient lay on the operating table in the supine position. Videokeratography was performed with the patient seated, and the degree of axial misalignment was determined by measuring the angle between the conjunctival mark and the horizontal axis identified on the video image.

RESULTS

Mean axial misalignment for all patients was 4.4 degrees +/- 2.8 (SD), which could theoretically cause about a 15% loss of surgical effect. The maximal misalignment was 14 degrees, which would correspond to a 48% loss of astigmatic correction.

CONCLUSION

The results of this study suggest that intraoperative identification of the astigmatism axis without using reference points may reduce the surgical effect because of axis misalignment. The use of a reference point and preoperative videokeratography may increase the accuracy of identification of the astigmatism axis.

Subretinal fluid drainage with the erbium:YAG laser in rabbit eyes

BACKGROUND AND OBJECTIVE

To evaluate the efficacy and safety of the erbium:yttrium-aluminum-garnet (Er:YAG) laser for choroidotomy as a means of performing external drainage of subretinal fluid with less risk of choroidal bleeding.

MATERIALS AND METHODS

The authors tested this application in a rabbit model of retinal detachment by evaluating the effects of Er:YAG laser energy on the bare choroid at various energy settings (1, 2, 3, or 5 mJ/pulse) and repetition rates (2, 4, 10, or 30 Hz).

RESULTS

Although the choroid was not perforated at low energy and frequency settings, choroidotomy was successfully achieved as energy and repetition rate were increased. Through higher energy levels per pulse and higher repetition rates, choroidotomy was achieved at lower total energy levels. No retinal damage was detected after laser choroidotomy. Choroidal bleeding was noted in 2 of 97 eyes; however, no subretinal hemorrhage occurred.

CONCLUSION

These results indicate that the Er:YAG laser may be a clinically useful tool for retinal reattachment surgery.

Expression of a mucin-like glycoprotein produced by ocular surface epithelium in normal and keratinized cells

PURPOSE

We previously characterized a monoclonal antibody (H185) to a mucin-like glycoprotein produced by human ocular surface epithelium. In the current study, we used H185 to investigate the pattern of the mucin-like glycoprotein in normal and keratinized apical cells of the ocular surface epithelium.

METHODS

We compared the cell characteristics and the pattern of H185 binding in cytologically and immunohistochemically stained samples of apical cells of conjunctival surface epithelium from 20 normal subjects and six patients before and after treatment for superior limbic keratoconjunctivitis.

RESULTS

In the superior bulbar conjunctiva of normal subjects, the intensity with which H185 antibody bound to apical surface epithelial cells varied, with areas of high-, medium-, and low-intensity binding occurring in a mosaic pattern. This mosaic pattern, and presumably expression of the mucin-like glycoprotein, was absent or remarkably reduced in keratinized cells obtained from patients with superior limbic keratoconjunctivitis before treatment. However, the pattern of H185 binding was normal in samples obtained 2 months after the start of treatment for superior limbic keratoconjunctivitis, and cells had recovered their normal small, round appearance.

CONCLUSION

When they are keratinized, apical cells of the ocular surface epithelium are altered in appearance and lack the normal mosaic pattern of expression of a mucin-like glycoprotein.

Value of thyroid stimulating antibody in the diagnosis of thyroid associated ophthalmopathy of euthyroid patients

AIMS/BACKGROUND

Thyroid associated ophthalmopathy (TAO) of euthyroid patients is difficult to diagnose because clinical findings overlap with other conditions, and no confirmatory diagnostic tests are available. Recently, it was reported that TSH binding inhibitor immunoglobulin (TBII) and thyroid stimulating antibody (TSAb) are sensitive markers of TAO. The sensitivity of these antibodies in the detection of TAO were therefore studied to determine if they could be a useful criterion in the diagnosis of TAO of euthyroid patients.

METHODS

Serum values of TBII and TSAb of 35 patients with euthyroid TAO (group A) were compared with those of 27 patients with Graves' disease and TAO (group B). The relation between the serum value of TSAb and the eye symptoms of patients with euthyroid TAO were also examined by multiple linear regression analysis.

RESULTS

In group A, TBII was positive in 10 cases (28.6%) and TSAb was positive in 29 cases (82.9%). In group B, both TBII and TSAb were positive in all cases (100%). The titre of serum TBII in group A (15.6% (SD 18.0%)) was significantly lower (p < 0.0001) than in group B (57.9% (21.5%)). The titre of serum TSAb in group A (1400.9% (2163.9%)) was significantly lower (p = 0.0026) than in group B (2243.9% (1472.8%)). Among the eye findings of patients with euthyroid TAO, keratopathy was significantly (p = 0.034) related to the value of TSAb.

CONCLUSION

These results suggest that the activity of TSAb is a more sensitive marker of euthyroid TAO than is TBII, and could be a useful criterion in the diagnosis of TAO of euthyroid patients.