The prevalence of herpes family virus DNA in the conjunctiva of patients positive and negative for human immunodeficiency virus using the polymerase chain reaction

ObjectiveTo help understand the pathogenesis of herpes family virus ocular infection among patients positive for HIV, the authors compared the rates of detection of herpes family virus DNA from the conjunctiva of patients who are positive and negative for human immunodeficiency virus (HIV) using the polymerase chain reaction (PCR).DesignCross-sectional study.ParticipantsThe conjunctival scrapings of 30 patients positive for HIV and 30 patients negative for HIV were examined.InterventionPCR was used to assay for the presence of herpes simplex virus type 1 (HSV), varicella-zoster virus (VZV), cytomegalovirus (CMV), and Epstein-Barr virus (EBV) DNA (n = 240 samples).Main outcome measureThe rate of detection of virus DNA in the two groups, controlling for age, gender, and race, was measured.ResultsHSV and VZV DNA were not detected in any of the HIV-positive or HIV-negative samples. CMV DNA was detected in 20% (6 of 30) of patients positive for HIV and was undetected in control subjects negative for HIV (P = 0.01). EBV DNA was detected in 40% (12 of 30) of patients positive for HIV and in 47% (14 of 30) of control subjects negative for HIV (P = 0.58).ConclusionsThere was no difference in the frequency of detection of HSV, VZV, or EBV DNA from the conjunctiva of patients positive or negative for HIV. Only CMV DNA was detected at a significantly higher rate in the conjunctiva of patients positive for HIV compared with control subjects negative for HIV. These different rates of peripheral virus shedding may be one possible explanation for the different rates of clinical infection among the herpes family viruses among patients positive for HIV.     

Detecting herpesvirus DNA in uveitis using the polymerase chain reaction.

BACKGROUND: Herpesviruses are involved in the pathogenesis of many ocular diseases including keratitis, iridocyclitis, and acute retinal necrosis syndrome. The rapid and accurate diagnosis of herpetic infections has become increasingly important with the rising incidence of immunosuppressive diseases. The purpose of this study was to evaluate the use of the polymerase chain reaction (PCR) to detect herpesvirus DNA in uveitis patients. METHODS: Aqueous samples were aspirated from 11 patients with active uveitis of suspected viral origin. Using PCR, masked samples were assayed for herpes simplex virus (HSV), varicella zoster virus (VZV), and cytomegalovirus (CMV) to assist in supporting the clinical diagnosis of viral aetiology. Masked controls included 10 aqueous humour specimens from normal patients undergoing cataract surgery and specimens from seven patients diagnosed with active non-viral uveitis--Behçet's disease, sarcoidosis, Fuchs' heterochromic iridocyclitis, or Harada's disease. RESULTS: Ten of 11 cases clinically diagnosed as being of possible viral aetiology yielded aqueous PCR positive for a herpesvirus. Eight patients were PCR positive for amplified HSV DNA, of whom two had acute retinal necrosis, one had corneal endotheliitis, and five had recurrent iridocyclitis. VZV DNA was detected in one case of iridocyclitis, and CMV DNA in one case of chorioretinitis. Successful therapy was based on the PCR results. Ten normal aqueous specimens and the seven uveitis samples from cases not suspected of a viral aetiology were PCR negative for HSV, VZV, and CMV. CONCLUSION: These results demonstrate that detecting herpesvirus DNA in the aqueous humour is useful to support a clinical diagnosis of viral uveitis.     

Multiplex polymerase chain reaction for the detection of herpes simplex virus, varicella-zoster virus and cytomegalovirus in ocular specimens

PURPOSE: A majority of ocular viral diseases are caused by herpes group of viruses. Such infections, especially atypical herpetic keratitis, iridocyclitis and intra-ocular inflammations, can often present with overlapping clinical manifestations misleading the diagnosis. Molecular techniques are most useful in such instances for an accurate and rapid diagnosis since conventional methods are time consuming and less sensitive. A multiplex PCR was developed and used for the detection of herpes simplex virus (HSV), varicella zoster virus (VZV), and cytomegalovirus (CMV) in ocular samples. METHODS: One hundred and forty six ocular samples (corneal scrapings - 52, aqueous fluid - 36, vitreous fluid - 31, tissues - 26, skin vesicle scraping - 1) were included in the study. The sensitivity of the assay was determined using serial dilutions of standard strains of HSV, VZV, and CMV vis-à-vis plaque forming assay. RESULTS: The sensitivity of the assay was 4, 4 and 12 PFU/ml or 20, 20 and 60 genome copy numbers of HSV, VZV and CMV respectively. Using DNA from various sources (fungal, bacterial, human leukocytes, tissues) along with standard positive controls, the assay was found to be highly specific. HSV DNA was detected in majority of the clinical samples (33.6%), most frequent being corneal samples. Comparatively, VZV and CMV infections were detected in small number of samples (VZV-3, CMV-2). CONCLUSIONS: We found the assay very useful in our set-up whenever a differential diagnosis of herpetic infections was suggested by the ophthalmologist. The multiplex PCR we have described here can be of greater value in clinics with larger number of patients suspected of having HSV, VZV or CMV infections.     

Diagnostic assays in cytomegalovirus retinitis: detection of herpesvirus by simultaneous application of the polymerase chain reaction and local antibody analysis on ocular fluid.

AIM: To determine the value of the polymerase chain reaction (PCR) technique and the analysis of intraocularly produced antibodies by calculating a Goldmann-Witmer quotient (GWq) as diagnostic assays in the confirmation of a clinically diagnosed cytomegalovirus (CMV) retinitis in a group of unselected AIDS patients. METHODS: Eleven samples of undiluted ocular fluid, obtained from nine AIDS patients with a clinically diagnosed CMV retinitis were analysed for the presence of genomic DNA from CMV, HSV-1, VZV, and EBV by PCR. Nine of these samples were analysed for the presence of locally produced IgG antibodies against these herpesviruses by calculating a GWq. Ten samples obtained from patients with various entities of clinical non-herpetic uveitis and 17 samples of aqueous humour obtained at cataract surgery were used as controls. RESULTS: In 10 out of 11 samples from AIDS patients (91%) the presence of CMV DNA was demonstrated. In four out of nine (44%) patients this was accompanied by CMV DNA in the blood indicating a CMV viraemia. In one sample, VZV DNA was detected and in another sample both CMV and VZV DNA were detected. No HSV-1 or EBV DNA could be demonstrated in these 11 samples. In contrast, simultaneous analysis of locally produced IgG antibodies against herpesviruses could not confirm the initial diagnosis of CMV retinitis. Ocular fluid samples obtained from 10 control uveitis patients were negative for DNA from CMV, VZV, and EBV by PCR. In one of 10 uveitis control samples HSV-1 DNA was detected; antibody analysis did not confirm this. In the uveitis control group, a significant GWq was calculated in one sample for HSV-1 and in another sample for VZV. The cataract control samples were all herpesvirus DNA negative by PCR. CONCLUSIONS: To establish the diagnosis of CMV retinitis in AIDS patients, ophthalmoscopic examination is a sensitive method. In confirming a diagnosis in indistinctive cases, application of a PCR assay detecting CMV DNA is a more sensitive method than analysis of locally produced antibodies by calculating a GWq. In clinical non-herpetic uveitis, secondary release of HSV-1 and VZV should be considered requiring additional therapeutic anticipation.     

The diagnostic significance of enzyme linked immuno-sorbent assay for herpes simplex,varicella zoster and cytomegalovirus retinitis

PURPOSE: To evaluate the diagnostic usefulness of enzyme linked immuno-sorbent assay (ELISA) in single serum samples to associate herpes simplex virus (HSV), varicella zoster virus (VZV) or cytomegalovirus (CMV) with viral retinitis as against polymerase chain reaction (PCR) on intraocular specimens. It was also designed to study the seroprevalence in normal healthy individuals, and the genomic prevalence of HSV, VZV and CMV in patients without an active viral inflammatory process. METHODS: PCR for the detection of HSV, VZV and CMV genomes was done on 33 and 90 intraocular fluids from viral retinal patients and non-viral controls respectively. ELISA was done on 30 and 100 serum samples from viral retinitis patients and normal healthy controls respectively. RESULTS: PCR did not detect HSV, VZV and CMV genomes except one, in which VZV-DNA was detected. ELISA showed prevalence rates of 28%, 83% and 90% for antibodies against HSV, VZV and CMV respectively in the normal population. In the 30 viral retinitis patients, PCR detected HSV-DNA in 2 (6.7%), VZV-DNA in 7 (23.3%) and CMV-DNA in 6 (20.0%) patients, while ELISA detected antibodies against HSV, VZV and CMV in 13 (43.3%), 24 (80.0%) and 23 (76.7%) patients respectively. ELISA was of value in indirect diagnosis only in 6 (20.0%) as compared to 15 (50.0%) of 30 patients by PCR, this difference was statistically significant (McNemar test, P value = 0.005). CONCLUSION: Serology by ELISA is no longer a useful diagnostic tool to associate HSV, VZV and CMV viruses with viral retinitis.     

Investigating a viral etiology for keratoconjunctivitis sicca among patients who are positive for human immunodeficiency virus

PURPOSE: Herpesvirus infection of the lacrimal gland was investigated as an etiologic factor for keratoconjunctivitis sicca in patients who were positive for human immunodeficiency virus (HIV). METHODS: In this cross-sectional study, we recorded the Schirmer tests and tear break-up times (TBUTs) among 30 patients who were positive for HIV. Dry-eye state was defined as a Schirmer test of <10 mm of wetting at 5 min or a TBUT of <10 s. The polymerase chain reaction assay (PCR) for herpes family viruses [Epstein-Barr virus (EBV), cytomegalovirus (CMV), herpes simplex virus (HSV), and varicella-zoster virus (VZV)] was performed on the conjunctival and tear specimens of the 30 HIV-positive patients by using virus-specific single primers. We compared the rates of virus DNA detection among dry-eye and non-dry-eye patients by calculating the odds ratio of detection for each virus. RESULTS: The odds ratio of viral DNA detection was adjusted for age, gender, race, CD4 count, and duration of HIV positivity. The adjusted odds ratios of EBV DNA detection among dry-eye to non-dry-eye patients were 1.30 (p = 0.79) and 0.97 (p = 0.98) by using Schirmer tests and TBUTs, respectively. For CMV, the adjusted odds ratios among dry-eye to non-dry-eye patients were 1.94 (p = 0.58) with Schirmer tests and 1.02 (p = 0.99) with TBUTs. HSV and VZV DNA were not detected in any samples. CONCLUSION: Our study does not support the role of herpesvirus infection of the lacrimal gland as a causative factor in the pathogenesis of dry eyes in patients positive for HIV.     

Rose bengal and lissamine green inhibit detection of herpes simplex virus by PCR

PURPOSE: To determine whether rose bengal and lissamine green affect polymerase chain reaction (PCR) detection of herpes simplex virus (HSV). DESIGN: Laboratory investigation. METHODS: Diagnostic corneal scrapings were evaluated for PCR inhibitory activity. Dacron swabs inoculated with rose bengal and lissamine green were processed as clinical samples, inoculated with control HSV, varicella zoster (VZV), cytomegalovirus (CMV), and toxoplasma DNA and prepared for PCR. The effects of calcium alginate and cotton swabs were also evaluated. RESULTS: Rose bengal, lissamine green, and calcium alginate not only inhibit PCR detection of HSV DNA, but also detection of VZV, CMV, and toxoplasma DNA. This inhibition could be overcome by serial dilution and by DNA purification of the sample before PCR. CONCLUSIONS: Rose bengal, lissamine green, and calcium alginate can inhibit PCR detection of HSV DNA. Clinical scrapings to be sent for PCR diagnostic testing should be taken before instillation of rose bengal or lissamine green.     

Polymerase chain reaction and Goldmann-Witmer coefficient analysis are complimentary for the diagnosis of infectious uveitis

PURPOSE: To determine the relative contribution of the analysis of intraocular antibody production and the polymerase chain reaction (PCR) in aqueous humor (AH) to the diagnosis of infectious uveitis. DESIGN: Retrospective case-control study. METHODS: Paired AH and serum samples from 230 patients suspected of infectious uveitis were examined for intraocular antibody production against herpes simplex virus (HSV), varicella zoster virus (VZV), and Toxoplasma gondii by calculating the Goldmann-Witmer coefficient (GWC). In addition, AH samples were investigated by real-time PCR to determine the presence of microbial DNA. RESULTS: Positive results were obtained in 54 cases (23%): 13 HSV (24%), 16 VZV (30%), and 25 T gondii (46%). Of these, 23 (43%) were positive for both GWC and PCR, 26 (48%) only for GWC, and 5 (9%) only for PCR. With PCR as the sole diagnostic approach, a correct diagnosis of the infectious etiology would have been missed in 34% of cases for the herpes viruses and in 64% for T gondii. Analysis of the relationship between a positive laboratory diagnosis and the time of sampling after onset of ocular disease demonstrated that intraocular antibody production was found throughout the course of the diseases. Viral DNA was more readily detected early in infection. In contrast, T gondii nucleic acid was not detected until 3 weeks after onset of ocular disease. CONCLUSIONS: Analysis of intraocular antibody production contributed considerably to the etiological diagnosis of infectious uveitis, most notably of ocular toxoplasmosis early after onset of disease. Therefore, both PCR and GWC determination might be performed for comprehensive diagnosis of intraocular infections.     

Effects of topical anaesthetics and fluorescein on the real-time PCR used for the diagnosis of Herpesviruses and Acanthamoeba keratitis

BACKGROUND: The early microbiological diagnosis of corneal infections may prevent the condition from worsening. AIM: To study the potential interferences of oxybuprocain and fluorescein solutions used by ophthalmologists on the performances of the real-time polymerase chain reaction (PCR) carried out as routine test for diagnosis of keratitis. METHODS: Quantified suspensions of Herpes simplex virus (HSV1), Varicella zoster virus (VZV), Cytomegalovirus (CMV) and Acanthamoeba with and without oxybuprocain or fluorescein added before DNA extraction were tested by real-time PCR. RESULTS: The capacities of the real-time PCR to detect HSV, VZV, CMV and Acanthamoeba were reduced by oxybuprocain and fluorescein. Both products diluted to 1/16 reduced the PCR detection capacities for more than 2 logs (DNA copies/sample). CONCLUSIONS: The simultaneous introduction of fluorescein or topical anaesthetics into the tubes containing the specimens to be tested by PCR may lead to false negative results. Because corneal specimens for microbiological diagnosis of keratitis are obtained after topical administration of anaesthetics and corneal staining with fluorescein, ophthalmologists should be aware to rinse the eye surface intensively with appropriate eye solutions to minimise the risks of misdiagnosis.     

Searching for viral antibodies and genome in intraocular fluids of patients with Fuchs uveitis and non-infectious uveitis

Background

To characterise the polyspecific intraocular antibody synthesis in aqueous humor of patients with Fuchs uveitis and other types of non-infectious uveitis.

Methods

Aqueous and serum samples collected from 24 patients with Fuchs uveitis, 21 patients with non-infectious uveitis, and 27 healthy subjects undergoing elective cataract surgery (control group) were analysed. In addition, vitreous samples, collected from seven uveitis patients (five Fuchs and two panuveitis) during retinal surgery, were examined. Specific immunoglobulin G antibodies against cytomegalovirus (CMV), rubella virus, herpes simplex virus (HSV), and varicella zoster virus (VZV) were investigated, and Goldmann–Witmer coefficients (GWCs) were calculated. Real-time PCR was performed to detect viral genome for HSV, VZV, and CMV, while nested PCR was conducted to detect rubella RNA.

Results

None of the control samples tested positive for any of the viral antibodies investigated. Intraocular antibody production was found in eight samples of patients affected by Fuchs uveitis (6/8 positive for rubella virus and 2/8 positive for herpes virus). Among patients with non-infectious uveitis, three tested positive for intraocular antibody production (one RV, one HSV and one for VZV). PCR was positive for RV in two patients with Fuchs uveitis, in three patients with non-infectious uveitis (one for RV and two for HSV), and in three control subjects (one for CMV and one for HSV).

Conclusions

Our series confirmed the presence of specific viral antibodies, especially against rubella virus, in the subgroup of patients affected by Fuchs uveitis, suggesting that this virus may be responsible for this chronic inflammatory condition. Rubella virus is probably the main causative agent of Fuchs uveitis, but other viruses may also be involved in the pathogenesis of this disease.     

Cytomegalovirus in aqueous humor from an eye with corneal endotheliitis

PURPOSE: To report cytomegalovirus (CMV) DNA in aqueous humor from a patient with unilateral corneal endotheliitis. DESIGN: Case report. METHODS: A 51-year-old man presented with unilateral corneal endotheliitis with linear keratic precipitates and coin-shaped lesions. Tear and aqueous humor samples were subjected to polymerase chain reaction to look for DNA from herpes simplex virus (HSV), varicella zoster virus (VZV), and CMV. RESULTS: Aqueous humor from the diseased eye contained DNA from CMV but not HSV or VZV. Its specificity was confirmed by Southern blot tests. Intravenous ganciclovir treatment resulted in the localization of his corneal edema and the reduction in keratic precipitates. There was severe destruction of corneal endothelial cells. CMV DNA was not detected in tears or control samples. CONCLUSIONS: In this healthy man with corneal endotheliitis, we detected CMV DNA in aqueous humor from the affected eye, but not HSV or VZV. This suggests that CMV may cause corneal endotheliitis in patients without immunodeficiency.     

The role of common viral ocular pathogens in Thygeson's superficial punctate keratitis

BACKGROUND/AIMS: The aetiology of Thygeson's superficial punctate keratitis (TSPK) remains elusive. A viral aetiology has been suggested by the absence of bacterial infection and clinical resemblance to other viral keratopathies. We report the results of polymerase chain reaction analysis for the detection of herpes simplex virus (HSV) 1 and 2, herpes zoster virus, varicella zoster virus (VZV) and adenovirus from corneal epithelial samples from patients with active signs and symptoms of TSPK. METHODS: Schirmer strip impressions were taken from the epithelium of eight patients with a known history of TSPK and symptoms and signs of active disease. Three patients were recruited as positive controls (two with herpes simplex keratitis and one with herpes zoster ophthalmicus). Samples from a further three patients acted as negative controls. All 14 samples underwent polymerase chain reaction testing for HSV 1, HSV 2, VZV and adenovirus. RESULTS: DNA corresponding to the expected viral DNA was amplified from all three positive control samples. The three negative control samples showed no evidence of viral DNA. Similarly, all samples from patients with TSPK showed no evidence of the presence of HSV 1, HSV 2, VZV or adenovirus. CONCLUSION: We conclude that HSV, VZV and adenovirus are not present in the epithelium of patients with TSPK. These results are considered in light of existing theories regarding the aetiology and treatment of this condition.     

Viral causes of unexplained anterior uveitis in Thailand

Aims

To assess the possible role of virus infection in patients with unexplained anterior uveitis (AU).

Methods

Intraocular fluid and plasma samples of 30 HIV-negative AU patients who were unresponsive or poorly responsive to topical steroid therapy were analyzed for nucleic acid of cytomegalovirus (CMV), herpes simplex virus (HSV), and varicella zoster virus (VZV) by real-time polymerase chain reaction (PCR) and for intraocular antibodies against these viruses by Goldmann–Witmer coefficient (GWC) analysis. Of these 30 cases, 21 were tested for rubella virus by GWC analysis, 16 of which also had PCR assessment of aqueous for rubella virus.

Results

Viral uveitis determined by either real-time PCR and/or GWC was documented in 20 out of 30 patients (67%). Of 30 paired samples tested by both methods for HSV, CMV, and VZV, 15 showed positive results (CMV (10), HSV (4), and VZV (1)). Real-time PCR was positive in 8/15 (53%), whereas GWC was positive in 10/15 (67%). Out of 10 CMV-positive patients, four had endotheliitis, two had Posner–Schlossman syndrome, and one Fuchs heterochromic uveitis syndrome (FHUS). Five out of 21 (24%) samples tested by GWC for Rubella virus were positive, three of which exhibited clinical features of FHUS.

Conclusions

Our results indicate that CMV is a major cause of AU in Thailand and show that FHUS can be caused by both CMV and Rubella virus.     

The possible role of herpes viruses in multifocal choroiditis and panuveitis

Summary 7 cases of multifocal choroiditis and panuveitis are reported here (6 females, 1 male). All clinical data were carefully considered. In all cases an aqueous sampling was made for the detection of anti-herpes virus antibodies in aqueous and serum. 3 specificities were tested: herpes simplex (HSV), herpes zoster (HVZ) and cytomegalovirus (CMV).An intraocular synthesis of specific antibodies was found against VZV in 2 cases and against HSV in 1 case. There was another presumptive case for HSV.     

VZV retinal vasculitis without systemic infection: diagnosis and monitoring with quantitative polymerase chain reaction

To report a case of unilateral varicella zoster virus (VZV) retinal vasculitis aspect in an immunocompetent child without systemic infection. Clinically, no signs of retinal necrosis or frosted branch vasculitis were present. This is an observational case report. Quantitative PCR was performed on the aqueous humor (AH) using primers specific for herpes virus (cytomegalovirus, Epstein-Barr virus, herpes simplex virus 1–2, and VZV). The patient was treated with intravenous acyclovir, intravitreous ganciclovir, and oral valacyclovir. A positive quantitative PCR result was found for VZV DNA (1.72 × 10⁶ viral copies/ml) in the AH. After 6 months, PCR of the AH was negative. Herpes viruses are involved in the pathogenesis of isolated retinal vasculitis. This case demonstrates that quantitative PCR is useful to detect viral DNA in AH and to monitor the viral activity and the therapeutic response.     

Infectious uveitis in immunocompromised patients and the diagnostic value of polymerase chain reaction and Goldmann-Witmer coefficient in aqueous analysis

PURPOSE: To establish the causes of uveitis in immunocompromised patients and to determine the contribution of polymerase chain reaction (PCR) and Goldmann-Witmer coefficient (GWC) analysis of aqueous humor in patients with an infectious etiology. DESIGN: Retrospective case series of 56 consecutive immunocompromised patients with uveitis. METHODS: All patients underwent full ophthalmologic examination and laboratory blood analysis for uveitis. Aqueous humor analyses were performed using PCR and GWC for cytomegalovirus (CMV), herpes simplex virus (HSV), varicella zoster virus (VZV), and Toxoplasma gondii. RESULTS: Of 56 immunocompromised patients, 43 (77%), all posterior and panuveitis, had intraocular infections. Twenty-one (49%) had CMV, three (7%) had VZV, 11 (26%) had T. gondii, six (14%) had Treponema pallidum, and one (2%) each had Aspergillus and Candida. In AIDS patients, CMV was the most common cause. A strong correlation between AIDS and ocular syphilis was also observed (P = .007). In nonAIDS immunocompromised patients, T. gondii was most frequently detected. Twenty-seven patients were examined by both PCR and GWC; five (18.5%) were positive by both assays, 15 (55.5%) were positive by PCR alone and seven (26%) by GWC alone. Viral infections were detected by PCR in 16 of 17 (94%) cases; T. gondii in four of 10 (40%) patients. Using GWC, a viral infection was diagnosed in three of 17 (18%) and T. gondii in nine of 10 (90%) cases. CONCLUSIONS: In immunocompromised patients, PCR is superior in diagnosing viral infections. Analysis of intraocular antibody production played a decisive role in the diagnosis of ocular toxoplasmosis.     

Polymerase chain reaction for diagnosis of herpetic intraocular inflammation

The authors present a polymerase chain reaction method for rapid and direct diagnosis of herpetic intraocular infections using small volume samples of intraocular fluid from 29 patients with various intraocular inflammatory diseases and 24 controls with senile cataract. Of six patients with early acute retinal necrosis from whom aqueous humor was tested, four were found to be positive for the presence of varicella-zoster (VZV) DNA while the other two were positive for the presence of herpes simplex virus (HSV) DNA. One of the patients with HSV DNA had been tested at an extremely early stage, at which time the aqueous humor viral antibody ratio did not predict a specific viral infection. Among four patients with acute retinal necrosis in relatively late stages following treatment with acyclovir from whom vitreous was obtained and tested, only one was found to have the presence of any viral DNA (VZV). On the other hand, the vitreous viral antibody ratio was found to be predictive of VZV infection in all four cases. VZV DNA was also detected in aqueous humor samples from four patients with suspected herpes zoster anterior uveitis, while HSV DNA was found in the aqueous humor of one patient with nonspecific keratouveitis. Neither human cytomegalovirus DNA nor human herpesvirus-6 DNA was detected in any sample included in this study. Finally, Epstein-Barr virus DNA was detected in the aqueous humor of the majority of patients studied and identified in cataract patients as well, suggesting either low specificity of the authors' assay for this virus or ubiquity of this virus in human eyes. In summary, the PCR method proved to be a very useful tool in establishing an etiological diagnosis in patients in the early stages of acute retinal necrosis, and in patients with anterior uveitis due to suspected HSV or VZV infection.     

Polymerase chain reaction for diagnosis of herpetic intraocular inflammation

The authors present a polymerase chain reaction method for rapid and direct diagnosis of herpetic intraocular infections using small volume samples of intraocular fluid from 29 patients with various intraocular inflammatory diseases and 24 controls with senile cataract. Of six patients with early acute retinal necrosis from whom aqueous humor was tested, four were found to be positive for the presence of varicella-zoster (VZV) DNA while the other two were positive for the presence of herpes simplex virus (HSV) DNA. One of the patients with HSV DNA had been tested at an extremely early stage, at which time the aqueous humor viral antibody ratio did not predict a specific viral infection. Among four patients with acute retinal necrosis in relatively late stages following treatment with acyclovir from whom vitreous was obtained and tested, only one was found to have the presence of any viral DNA (VZV). On the other hand, the vitreous viral antibody ratio was found to be predictive of VZV infection in all four cases. VZV DNA was also detected in aqueous humor samples from four patients with suspected herpes zoster anterior uveitis, while HSV DNA was found in the aqueous humor of one patient with nonspecific keratouveitis. Neither human cytomegalovirus DNA nor human herpesvirus-6 DNA was detected in any sample included in this study. Finally, Epstein-Barr virus DNA was detected in the aqueous humor of the majority of patients studied and identified in cataract patients as well, suggesting either low specificity of the authors' assay for this virus or ubiquity of this virus in human eyes. In summary, the PCR method proved to be a very useful tool in establishing an etiological diagnosis in patients in the early stages of acute retinal necrosis, and in patients with anterior uveitis due to suspected HSV or VZV infection.     

Detection of varicella zoster virus DNA in some patients with giant cell arteritis

PURPOSE: The purpose of this study was to determine whether an association exists between giant cell arteritis (GCA) and the presence of varicella-zoster virus (VZV), by using histologic, molecular, immunohistochemical, and ultrastructural analyses of temporal artery biopsy specimens. METHODS: In a randomized masked study, 64 temporal artery biopsy specimens were analyzed by PCR for VZV DNA. The samples included 35 specimens histologically positive and 29 specimens histologically negative for GCA. Immunohistochemical staining for VZV viral antigen IE-63 was performed on seven of the specimens positive for GCA and five negative specimens. Transmission electron microscopy (TEM) was performed on five of the specimens positive for GCA. RESULTS:PCR was positive for VZV DNA in 9 (26%) temporal arteries tested that showed histologic evidence of GCA. The remaining 26 histologically positive temporal arteries and all 29 histologically negative arteries tested gave negative PCR results for VZV DNA. Statistical analysis (z-test) comparing the association of VZV DNA between the specimens that were positive and negative for GCA showed a significant difference (P = 0.010). Immunohistochemical studies were positive in several biopsy specimens within adventitial histiocytes-macrophages, but these results did not correlate with either the presence or absence of VZV DNA or with the histologic evidence of GCA. No viral particles were observed by TEM. CONCLUSIONS: This study showed a significant association of VZV DNA to temporal artery biopsy samples positive for GCA compared with the negative specimens. The results support the hypothesis that VZV may play a role in the pathogenesis of some cases of GCA. However, PCR, immunohistochemical, and electron microscopic findings suggest the virus is present at extremely low quantities, is abortively replicating, or is latent.     

Acute retinal necrosis--a case report

We present a case of acute retinal necrosis (ARN) which is a rare but devastating and rapidly progressive viral retinitis. It is caused mainly by Herpes simplex virus (HSV) or Varicella zoster virus (VZV) (2), but also Cytomegalovirus (CMV) and Epstein-Barr virus infections may be aethiological factors of ARN. A 17-year-old male patient was referred with history of painful sudden worsening of visual acuity in the left eye and the presence of floaters in the visual field of the right eye. Based on the ophthalmological examination the diagnosis of bilateral ARN was established. Aqueous humor aspirates were analyzed using polymerase chain reaction (PCR) for Herpes simplex virus (HSV), Varicella zoster virus (VZV), Cytomegalovirus (CMV) and Epstein-Baar virus (EBV). PCR confirmed the presence of Varicella zoster virus in aqueous humor samples. Prompt systemic antiviral therapy combined with steroids was initiated. Since a rapid and accurate diagnosis is crucial for prompt administration of antiviral therapy, PCR-based analysis of intraocular fluids orovides a valuable tool in the establishina an etiologic factor in patients with retinitis caused by herpesvirus.