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

The role of antibody indexes in clinical virology

BACKGROUND

Serological techniques are an essential part of the diagnostic tools used in clinical virology. Among these techniques, antibody indexes are not novel, but do require specific expertise. Their niche has expanded substantially in recent years due to increasing evidence of their performance to diagnose viral infections.

OBJECTIVES

This narrative review describes the background and clinical applications of antibody indexes. The first objective is to provide an overview of the theoretical background, insights for implementation, limitations and pitfalls. The second objective is to review the available evidence for the diagnostic performance, with a specific focus on viral encephalitis and uveitis.

SOURCES

A comprehensive literature search was performed in PubMed, including original studies and reviews, with no time limit on the studies included. The following search terms were used: antibody index, Goldmann-Witmer coefficient, Reibergram, viral encephalitis, viral uveitis, herpes simplex virus, varicella zoster virus, cytomegalovirus, Epstein-Barr virus, rubella virus, measles virus, enterovirus, influenza virus, flaviviruses.

CONTENT

Antibody indexes can support the diagnosis of a spectrum of viral infections in immune privileged sites such as the central nervous system and the eye, through the demonstration of virus-specific intrathecal or intraocular antibody production. This is especially useful in situations where PCR has a lower positivity rate: infections with rapid viral clearance due to natural immunity or treatment and chronic stages of viral infections.

IMPLICATIONS

Antibody indexes expand the clinical microbiologist's diagnostic toolbox. Careful interpretation of the results of these assays is crucial and further standardization of methods is required to improve interchangeability of results between laboratories.

Clinical Manifestations, Prognosis, and Vaccination Status of Patients With Rubella Virus-Associated Uveitis

PURPOSE

To assess the clinical and laboratory manifestations and vaccination status of uveitis patients positive for rubella virus (RV) in aqueous humor and investigate its relationship to Fuchs uveitis syndrome (FUS).

METHODS

Retrospective study of all uveitis patients, positive for RV in aqueous humor analysis (polymerase chain reaction [PCR] and/or Goldmann-Witmer coefficient [GWC]) between January 2010 and October 2016 at the ophthalmology departments in the Erasmus Medical Center (Rotterdam) and University Medical Center Utrecht. Outcomes of aqueous analyses of FUS patients during this period were assessed.

RESULTS

We included 127 patients (144 eyes) positive for RV in aqueous fluid: 23 (20%) by PCR, 120 (97%) by GWC, and 16 (13%) by both. The average age at first presentation was 37 years. Patients typically complained of blurred vision and exhibited a combination of unilateral anterior uveitis, keratic precipitates, vitritis, and absence of posterior synechiae, but the classical FUS was observed in a minority. The main cause of untreatable visual loss was glaucoma. Cystoid macular edema (CME) before intraocular surgery was not encountered. None of the unilateral cases developed involvement of the other eye. None of the patients was vaccinated against RV. All FUS patients, except 2 (5%), were positive for RV.

CONCLUSION

RV-associated uveitis and FUS are not exchangeable. Chronic anterior uveitis, vitritis, early development of cataract, and the absence of posterior synechiae and CME characterize RV-associated uveitis. Almost all FUS cases had documented intraocular RV infection, but only some of the patients with RV-associated uveitis presented with FUS.

Polymerase Chain Reaction and Goldmann-Witmer Coefficient Testing in the Diagnosis of Infectious Uveitis in HIV-Positive and HIV-Negative Patients in South Africa

PURPOSE

To use polymerase chain reaction (PCR) and Goldmann-Witmer coefficient (GWC) calculation to diagnose infectious uveitis.

METHODS

Prospective cross-sectional study.

RESULTS

Twenty-seven of 106 patients had positive PCR and/or GWC results on aqueous humor (AH) sampling and 15 of 27 (55.6%) were HIV-positive. Patients with non-anterior uveitis (NAU) were more likely to be HIV+ (p = 0.005). More than 1 possible pathogen was identified in 9 of 27 patients of whom 7 were HIV+. The final clinical diagnosis was discordant with AH findings in 9 of 27 cases. A positive EBV PCR result was associated with a discordant diagnosis (p = 0.001). All cases of herpetic anterior uveitis (42.9% HIV+) tested PCR-/GWC+ while all cases of herpetic NAU tested PCR+/GWC- (83.3% HIV+). All rubella virus cases were PCR+/GWC+.

CONCLUSION

PCR is useful to diagnose herpetic NAU in HIV+ patients while GWC is useful to diagnose herpetic anterior uveitis.

[Acute retinal necrosis from the virologist's perspective]

Acute retinal necrosis occurs in approximately one per million persons per year and is caused in approximately 70% of the cases by the varicella zoster virus or in about 30% of the cases by herpes simplex virus. The early diagnosis is primarily based on virus-specific polymerase chain reaction in fluid from the anterior chamber or vitreous humor and can be supported by the determination of specific antibody titers from fluid and serum. Virus detection provides the basis for early causative therapy which limits disease progression and risk of complications. Retinal infections by varicella zoster virus or herpes simplex virus are treated with aciclovir, ganciclovir, or famciclovir. Ganciclovir and valganciclovir are used for the therapy of retinal cytomegalovirus infections. In the case of resistance development, foscarnet or cidofovir are available as second line antiviral drugs. The early use of specific antiviral agents is a crucial prerequisite for optimized therapy of acute retinal necrosis.

Ocular complications of heart transplantation in a Chinese population

The purpose of this study was to investigate ocular complications among a group of patients on long-term, high-dose immunosuppression and corticosteroids for the maintenance of orthotopic heart transplants. Additionally, we provided information pertinent for the early diagnosis and treatment of eye diseases. In this study, we retrospectively assessed the clinical data of 138 patients with orthotopic heart transplantations from May 2000 to October 2005, including assessment of ophthalmic symptoms and signs, as well as the general condition, treatment, and prognosis. Of 138 transplant recipients examined (276 eyes), 47 eyes (17.0%) showed ocular surface diseases. Sixty-four (23.2%) had a posterior subcapsular cataract, and 16 (5.8%) corticosteroid glaucoma. Fifteen (5.6%) had ocular fundus diseases. Various ocular complications related to immunosuppression and corticosteroids appear among heart transplant patients. Cardiac surgeons and ophthalmologists must closely evaluate ocular symptoms in the posttransplantation period.

Advances in the diagnosis and immunotherapy for ocular inflammatory disease

Significant advances in the diagnosis and therapy for uveitis have been made to improve the quality of care for patients with ocular inflammatory diseases. While traditional ophthalmic examination techniques, fluorescein angiography, and optical coherence tomography continue to play a major role in the evaluation of patients with uveitis, the advent of spectral domain optical coherence tomography and fundus autofluorescence into clinical practice provides additional information about disease processes. Polymerase chain reaction and cytokine diagnostics have also continued to play a greater role in the evaluation of patients with inflammatory diseases. The biologic agents, a group of medications that targets cytokines and other soluble mediators of inflammation, have demonstrated promise in targeted immunotherapy for specific uveitic entities. Their ophthalmic indications have continued to expand, improving the therapeutic armentarium of uveitis specialists.

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.

Cytomegalovirus antibodies in tear fluid of patients with retinitis

The diagnosis of cytomegalovirus retinitis (CMV-R) is difficult and usually based on clinical criteria or invasive diagnostic procedures. The purpose of this study was to investigate a possible association between CMV-R and specific anti-CMV antibodies in tears. Paired tear and serum samples were obtained from 96 individuals, which included 20 children with congenital CMV infection and chorioretinitis, 56 adults with retinitis with clinical signs suggestive of viral infection, and 20 healthy control subjects, and were tested for CMV antibodies using ELISA. The prevalence of anti-CMV antibodies in tears was found to be 80% (16/20) in children, 35% (20/56) in adults, and 5% (1/20) in control subjects. Furthermore, high antibody levels were detected in 35% (7/20) of children and 10.7% (6/56) of adults with retinitis, and were not found in control subjects. There was a strong association between high tear levels of anti-CMV antibodies and active ocular infection. No correlations were found between tear and serum antibodies. ELISA sensitivity was 80% and specificity 95%. Further studies are needed to compare the tear and intraocular levels of CMV-specific antibodies in patients with retinitis to find out if CMV antibody testing in tear fluid could substitute for more invasive diagnostic procedures.

Rétinites nécrosantes herpétiques

The diagnosis of necrotic herpetic retinitis is suggested on clinical grounds, prompting urgent appropriate intravenous and intravitreal treatment. PCR on ocular samples is most often successful in identifying the herpetic agent. Classic acute retinal necrosis syndrome caused by herpes simplex or zoster virus and the different clinical forms present in immunocompetent or immunodepressed patients are described. The differential diagnosis includes atypical presentation of retinal necrosis caused by toxoplasmosis, syphilis, or ocular lymphoma; the ocular samples are useful in establishing the etiological diagnosis. We describe the different therapeutic strategies in the acute phase and as secondary prophylactic treatment. The clinical outcome appears to be influenced by rapid, appropriate treatment, limiting the extension of the retinal necrosis.

Clinical characteristics of acute HSV-2 retinal necrosis

PURPOSE

To report the clinical features and evaluate the visual outcome of eleven cases of herpes simplex virus-2 (HSV-2) related acute retinal necrosis syndrome (ARN).

DESIGN

Retrospective interventional case series.

METHODS

Twelve eyes of eleven patients from two European centers, diagnosed with HSV-2 related acute retinal necrosis syndrome were retrospectively reviewed. Herpes simplex virus-2 DNA was detected by polymerase chain reaction in intraocular fluids (aqueous and/or vitreous). Findings at initial examination, clinical evolution with antiviral therapy, complications and final visual acuity were evaluated.

RESULTS

Herpes simplex virus-2 DNA was detected in all cases. No sample was positive for more than one virus. The mean age of disease in the first eye was 36 years (ranged from 10 to 57 years). Five patients were women and six were men. All patients were immunocompetent. Previous medical history included neonatal herpes (n = 1), previous ARN (n = 3), trauma (n = 1) and systemic corticosteroid administration before occurrence of ARN (n = 3). Preexisting pigmented chorioretinal scars were found in three cases. Patients were treated with high dose intravenous acyclovir or foscarnet +/- intravitreal ganciclovir +/- interferon. The mean follow-up was 14.5 months (from 5 to 22 months). At the end of the follow-up period, five eyes (41.7%) showed improvement of visual acuity of two or more lines. Final visual acuity was 20/60 or better in four eyes (33.3%), 20/400 or better in four eyes (33.3%) and less than 20/400 in four eyes.

CONCLUSION

History of neonatal herpes, triggering events such as neurosurgery, periocular trauma, high-dose corticosteroids, and chorioretinal scars suggest that HSV-2 retinitis reflects reactivation of HSV-2 infection.

Prise en charge diagnostique et thérapeutique des rétinites nécrosantes herpétiques

PURPOSE

To study the viral cause and present the management of necrotizing herpetic retinopathies.

METHODS

Charts of patients presenting with acute retinal necrosis (ARN) or progressive outer retinal necrosis (PORN) diagnosed between March 1997 and June 2001 were retrospectively reviewed. Intraocular specimens were obtained in 33 cases to determine the viral cause using polymerase chain reaction-based assays and/or detection of intraocular antibody production.

RESULTS

The mean age was 43.4 Years. Herpesvirus genome was identified in 29 patients (80.5%). In the ARN group (32 patients, 38 eyes), herpes simplex virus (HSV) DNA was found in 11 patients (34.4%), varicella-zoster virus (VZV) in nine patients (28.1%), and cytomegalovirus (CMV) in four patients (12.5%). One patient (3.1%) presented an Epstein-Barr virus (EBV) infection. ARN was bilateral at initial examination in six patients and secondary bilateralization was observed in four patients. In the PORN group (four patients, eight eyes), the retinitis was bilateral and VZV DNA was detected in all cases. Two patients were treated with intravenous acyclovir, six with foscarnet alone, ten with intravenous foscarnet + acyclovir, 18 with intravenous foscarnet and intravitreous ganciclovir injections. Complications of necrotizing herpetic retinitis were cataract (26%), optic nerve atrophy (23.9%), and retinal detachment (17.4%). Final visual acuity was less or equal to 20/200 in 47.8% of cases.

CONCLUSIONS

It is important to determine the specific viral etiology since progression and prognosis may be different in herpetic necrotizing retinitis caused by HSV, VZV, or CMV. Visual prognosis is improved by intensive antiviral therapy, but remains poor if complications occur.

Cme review: polymerase chain reaction diagnostics for posterior segment disease

The polymerase chain reaction (PCR) is a powerful molecular biologic technique that permits detection and identification of infinitesimal quantities of DNA. It is well suited to the diagnosis of infectious posterior segment ocular inflammatory disease. In this review, the basic biochemistry of PCR, indications for its use, strengths and limitations to the technique, and examples of clinical application of PCR to posterior segment disease will be discussed. Emerging uses of PCR in linking pathogen to disease will also be outlined. After completion of this article, the reader will be able to describe the basic biochemistry and practical application of PCR in the diagnosis of posterior segment inflammatory disease, list the indications, advantages, and disadvantages of the technique, and outline the application of PCR diagnostics to individual differential diagnoses.

Vitreous aspiration needle tap in the diagnosis of intraocular inflammation

PURPOSE

To determine the safety of vitreous aspiration needle tap as a clinical procedure and its usefulness in helping to distinguish between infective, inflammatory, and malignant causes of uveitis.

DESIGN

Retrospective, noncomparative case series.

PARTICIPANTS

Data were collected for 53 patients who had undergone vitreous aspiration needle tap as an outpatient in the clinic.

METHODS

These patients underwent vitreous aspiration needle tap using a needle and syringe for the following indications: (1) when masquerade syndrome or infective retinitis was the primary diagnosis; and (2) to diagnose or exclude infective or malignant entities in patients not responding to treatment. The result of the analysis of the biopsy specimen and any complications that arose from the procedure were determined.

RESULTS

In this series, vitreous aspiration needle tap generated an adequate sample for the relevant investigations in 92% of cases. The initial diagnosis of intraocular malignancy or infection was confirmed in 40% of patients. The remaining patients were treated with immunosuppressives for the ocular inflammation and showed clinical improvement over the follow-up period. Multiple procedures were required in two patients to make the diagnosis of B-cell intraocular lymphoma and in two patients with acute retinal necrosis who were treated for the presenting clinical features.

CONCLUSIONS

Vitreous aspiration needle tap would seem to be a safe clinical procedure, which has a high success rate in differentiating between infectious, inflammatory, and malignant causes of uveitis. It is a quick procedure that can be carried out at the first outpatient visit.

Polymerase chain reaction analysis of aqueous humour samples in necrotising retinitis

AIM

To evaluate the diagnostic value of polymerase chain reaction (PCR) performed on aqueous humour for the detection of viral DNA in patients with necrotising herpetic retinitis.

METHODS

The clinical features and laboratory results of 22 patients (29 eyes) presenting with necrotising herpetic retinitis between March 1999 and June 2001 were reviewed retrospectively. Aqueous humour was obtained after anterior chamber paracentesis and PCR was performed in all cases.

RESULTS

Viral DNA was detected in the aqueous humour of 19 patients (86.4%). Epstein-Barr virus (EBV) seroconversion was evidenced in one additional patient. In the acute retinal necrosis (ARN) group (n = 19), varicella zoster virus (VZV) DNA was identified in six patients, herpes simplex virus 1 (HSV-1) DNA in two patients, herpes simplex virus 2 (HSV-2) DNA in four patients, and cytomegalovirus (CMV) genome in four patients. In the progressive outer retinal necrosis (PORN) group (n = 3), VZV DNA was detected in all patients. No sample was positive for more than one virus.

CONCLUSIONS

PCR analysis of aqueous humour in patients with clinical features of necrotising viral retinitis can provide specific aetiological orientation and the method appears to be safe and highly sensitive.

Herpes simplex virus type 1 (HSV-1)--induced retinitis following herpes simplex encephalitis: indications for brain-to-eye transmission of HSV-1

Herpes simplex encephalitis is a severe neurological disease with high mortality and morbidity rates. Reactivated herpes simplex virus type 1 (HSV-1) can cause relapses and might even spread to the retina, where it can induce a potentially blinding eye disease, known as acute retinal necrosis. In the present study, the HSV-1 strains in the brain and eye of 2 patients with acute retinal necrosis following an episode of herpes simplex encephalitis were genotyped. The HSV-1 strains in both the brain and eye were identical in each patient, but they differed interindividually. The data suggest brain-to-eye transmission of HSV-1 in these patients.

Changing therapeutic paradigms in CMV retinitis in AIDS

Cytomegalovirus (CMV) retinitis is a common ocular complication of immunosuppression. The management of CMV retinitis has been continuously evolving over the last decade. The mainstay of therapy remains ganciclovir and foscarnet. However, increasing resistance and ongoing toxicities to these agents remain a challenge. Additional frequently utilised agents include cidofovir and fomivirsen. The advent of highly active antiretroviral therapy (HAART) has allowed the restoration of immunocompetency to many patients previously challenged by CMV infection. In some circumstances, HAART has even eliminated the need for ongoing antiviral therapy. This paper reviews the current treatment modalities, including their toxicities and dosing recommendations.

Detection of human cytomegalovirus retinitis and monitoring of ganciclovir treatment using conjunctival swab with polymerase chain reaction in AIDS patients

This report studies the accuracy of conjunctival swab polymerase chain reaction (CS-PCR) for the diagnosis of human cytomegalovirus retinitis (HCMV) in AIDS patients. PCR and virus culture were used for the detection of HCMV in conjunctival swab, serum, and urine specimens from 38 AIDS patients between April 1996 and April 1998. The clinical utility of the identification of HCMV retinitis by these 6 different methods was demonstrated by their prediction power to estimate AIDS patients at risk of contracting HCMV retinitis. The sensitivity, specificity, positive predictive value, and negative predictive value of CS-PCR for the detection of HCMV retinitis were 91.5%, 80.9%, 60.8%, and 92.7%, respectively; for serum PCR were 74.3%, 81.7%, 57.2%, and 90.3%; for urine PCR were 100%, 17.3%, 20.4%, and 100%; for conjunctival swab culture were 22.7%, 100%, 100%, and 86%; for serum culture were 27.3%, 98.1%, 75%, and 86.4%; and for urine culture were 90.9%, 44.2%, 25.6%, and 95.8%.

Value of different assays for detection of human cytomegalovirus (HCMV) in predicting the development of HCMV disease in human immunodeficiency virus-infected patients

In the present prospective study, five blood tests for detection of human cytomegalovirus (HCMV), nucleic acid sequence-based amplification (NASBA) for detection of early (immediate-early antigen) and late (pp67) mRNA, PCR for detection of HCMV DNA (DNA PCR), culture, and pp65 antigenemia assay, and culture and DNA PCR of urine and throat swab specimens were compared for their abilities to predict the development of disease caused by HCMV (HCMV disease). Of 101 human immunodeficiency virus (HIV)-infected patients with Collapse

Key Words Collapse

MESH Headings

• AIDS-Related Opportunistic Infections/diagnosis
• AIDS-Related Opportunistic Infections/virology
• Adult
• Antigens, Viral/analysis
• Blood/virology
• Cytomegalovirus/genetics
• Cytomegalovirus/isolation & purification
• Cytomegalovirus/physiology
• Cytomegalovirus Infections/diagnosis
• Cytomegalovirus Infections/virology
• DNA, Viral/analysis
• Female
• Humans
• Immediate-Early Proteins/analysis
• Male
• Pharynx/virology
• Phosphoproteins/blood
• Polymerase Chain Reaction
• Predictive Value of Tests
• Prospective Studies
• Risk
• Urine/virology
• Viral Matrix Proteins/blood
• Viral Proteins/metabolism

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Grants Collapse

Affiliation(s)

B S Blank National AIDS Therapy Evaluation Center, Department of Internal Medicine, Academic Medical Center, University of Amsterdam, The Netherlands.
P L Meenhorst
J W Mulder
G J Weverling
H Putter
W Pauw
W C van Dijk
P Smits
S Lie-A-Ling
P Reiss
J M Lange

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Triple viral retinitis diagnosed by polymerase chain reaction of the vitreous biopsy in a patient with Richter syndrome

PURPOSE

To report the evaluation and identification of herpes viruses associated with retinitis in a patient with Richter syndrome.

METHODS

Diagnostic vitrectomy was performed on a patient with systemic leukemia and retinitis. The vitreous sample was evaluated by cytology, analysis of cytokines by ELISA, and detection of virus by polymerase chain reaction.

RESULTS

The vitreous biopsy specimen showed no malignant cells but predominant CD8+ lymphocyte infiltration with elevated interferon gamma and interleukin-6. DNA amplification and Southern blot analysis demonstrated DNA of herpes simplex, varicella-zoster, and cytomegalovirus.

CONCLUSION

Retinitis associated with multiple viruses in the vitreous biopsy may mimic leukemic infiltration in the eye.

Polymerase chain reaction-based assays of vitreous samples for the diagnosis of viral retinitis. Use in diagnostic dilemmas

OBJECTIVE

This study aimed to review the authors' results using polymerase chain reaction (PCR)-based assays for the diagnosis of viral retinitis.

DESIGN

The study design was a retrospective case series.

PARTICIPANTS

Thirty-seven patients (38 eyes) with active retinitis from whom vitreous biopsy specimens were received in the authors' laboratory for diagnostic evaluation.

INTERVENTION

Vitreous biopsy specimens were evaluated with previously described PCR-based assays for cytomegalovirus (CMV), varicella zoster virus (VZV), and herpes simplex virus (HSV) DNA; clinical histories were reviewed.

MAIN OUTCOME MEASURES

Laboratory findings and clinical course were measured.

RESULTS

The results of the authors' assays were consistent with the long-term clinical course of each patient. Cytomegalovirus, VZV, or HSV DNA was detected in the vitreous from 24 patients. Cytomegalovirus DNA was detected in vitreous biopsy specimens from 10 patients (11 eyes). Nine patients (ten eyes) with acquired immune deficiency syndrome ultimately were diagnosed with CMV retinitis as they were followed clinically over time. Varicella zoster virus DNA was detected in vitreous biopsy specimens from eight patients; seven adult patients were ultimately diagnosed with acute retinal necrosis or progressive outer retinal necrosis. Herpes simplex virus DNA was detected in vitreous biopsy specimens from six patients; five patients had previous or subsequent herpes encephalitis. No viral DNA was detected in the vitreous from 13 patients; all were ultimately diagnosed with toxoplasmosis, syphilis, Behcet disease, fungal endophthalmitis, or idiopathic inflammation.

CONCLUSIONS

These data further support the use of PCR-based assays of vitreous specimens in the diagnostic evaluation of patients with infectious retinitis.