Diagnostic vitrectomy for infectious uveitis

Injectable cross-linked hyaluronic acid hydrogels with epigallocatechin gallate loading as vitreous substitutes

Hyaluronic acid (HA) serves as a vitreous substitute owing to its ability to mimic the physical functions of native vitreous humor. However, pure HA hydrogels alone do not provide sufficient protection against potential inflammatory risks following vitrectomy. In this study, HA was crosslinked with 1,4-butanediol diglycidyl ether (BDDE) to form HA hydrogels (HB). Subsequently, the anti-inflammatory agent epigallocatechin gallate (EGCG) was added to the hydrogel (HBE) for ophthalmic applications as a vitreous substitute. The characterization results indicated the successful preparation of HB with transparency, refractive index, and osmolality similar to those of native vitreous humor, and with good injectability. The anti-inflammatory ability of HBE was also confirmed by the reduced expression of inflammatory genes in retinal pigment epithelial cells treated with HBE compared with those treated with HB. In a New Zealand white rabbit model undergoing vitreous substitution treatment, HBE 50 (EGCG 50 μM addition) exhibited positive results at 28 days post-surgery. These outcomes included restored intraocular pressure, improved electroretinogram responses, minimal increase in corneal thickness, and no inflammation during histological examination. This study demonstrated the potential of an injectable HA-BDDE cross-linked hydrogel containing EGCG as a vitreous substitute for vitrectomy applications, offering prolonged degradation time and anti-inflammatory effects postoperatively.

Evolution of research in diagnosis and management of uveitis over four decades in India

Uveitis and its complications are more common in the developing world, in which the condition occurs in up to 714 per 100,000 in the population and accounts for up to 25% of all blindness. In India, the ophthalmic sub speciality of uveitis greatly evolved in the last four decades. In the early decades most of the studies were epidemiological studies. In recent years, more research has been published due to tremendous advancements in clinical diagnosis, laboratory investigations and ancillary test and treatment modalities. In this review article, we did a medline search with key words 'uveitis' and 'India', and selectively incorporated articles showing the evolution of this sub-speciality in India.

Subretinal abscess due to nocardia in an immunosuppressed patient: a case report

Systemic nocardiosis is a rarely occurring pathology, but its hematogenous spread across the eye is even less likely to occur, with only a few recorded cases. Therefore, it is not usually taken into account when a subretinal abscess is being considered for a diagnosis. However, when confronting a case with a history of immunosupression and pulmonary disease, the examination of the ocular fundus may be a very successful approach. With such aim we introduce the case of a 45-year-old immunosupressed male, without a history of pulmonary disease, whose subretinal mass evolution is accordant with an abscess. In the end, being etiologically diagnosed by means of a vitrectomy, it was concluded that the abscess was due to an infection of nocardia cyriacigeorgica, an emergent pathogen. Thus the aforementioned case is to be considered in the present study, along others, in order to shed more light on a disease which may not be readily diagnosed on account of its infrequency.

Long-Term Safety and Efficacy of Pars Plana Vitrectomy for Uveitis: Experience of a Tertiary Referral Centre in the United Kingdom

AIM

To evaluate the effectiveness of pars plana vitrectomy (PPV) without macular intervention on uveitis eyes with persistent vitreous inflammation/opacities in terms of visual acuity (VA), intraocular inflammation and macular profile.

METHODS

We carried out a single-center retrospective study of patients with uveitic eyes that underwent PPV without intervention on the macula due to persistent vitreous inflammation/opacities. The primary outcome measures were best-corrected visual acuity (BCVA), intraocular inflammation and macular profile at 3, 12 and 24 months after surgery.

RESULTS

Twenty-seven eyes of twenty-six patients were analyzed. Overall, 77.8% had an improvement of VA (55% by 0.3 LogMAR or more); 62.5% of patients had no intraocular inflammation, and the number of patients on systemic steroids and second-line immunosuppressives was reduced by 26% at 12 months; 87.5% of patients had resolution of macular oedema at 12 months.

CONCLUSION

PPV for persistent vitreous inflammation/opacities is safe and effective, showing beneficial outcomes in terms of improvement of BCVA and the reduction in inflammation.

Vitreoretinal surgery in the management of infectious and non-infectious uveitis - a narrative review

PURPOSE

This study aims to conduct a narrative review about the current role of vitreoretinal surgery in the management of infectious and non-infectious uveitis.

METHODS

This review was performed based on a search of the PubMed database or on relevant published papers according to our current knowledge.

RESULTS

A total of 91 articles were identified in the literature review. With the advance of microincision vitrectomy surgery (MIVS), pars plana vitrectomy (PPV) has gained increasing popularity in the management of infectious and non-infectious uveitis. For diagnostic purposes, larger amounts of sample can be obtained by MIVS than traditional vitreous aspiration using needles. For treatment purposes, PPV removes vitreous opacities, decreases inflammatory cytokines and mediators of inflammation, and tackles related complications, including hypotony, epiretinal membrane, macular holes, and retinal detachment. Achieving optimum control of inflammation prior to surgery is important for surgical interventions for non-emergent therapeutic indications and complications of uveitis. Peri-operative inflammation management is essential for decreasing the risk of surgical intervention. An overall complication rate of 42-54% was reported with cataract to be the leading cause of complications.

CONCLUSION

Most reports affirm the role of PPV in the management of infectious and non-infectious uveitis, although the quality of data remains limited by a lack of applying standardized reporting outcomes, limitations in study design, and a paucity of prospective data.

Prevalence of Toxoplasmic Retinochoroiditis in an Australian Adult Population: a Community-Based Study

OBJECTIVE

Toxoplasmic retinochoroiditis is the most common clinical manifestation of an infection with the protozoan parasite, Toxoplasma gondii. Up to 50% of the human population is estimated to be infected with T. gondii. However, the epidemiology of toxoplasmic retinochoroiditis is not widely reported. We sought to estimate the prevalence of toxoplasmic retinochoroiditis in Australia using data collected as part of the Busselton Healthy Ageing Study.

DESIGN

Cross-sectional, community-based, prospective cohort study.

PARTICIPANTS

5,020 Australian adults (2,264 men and 2,756 women; age range of 45-69 years and median age of 58 years).

METHODS

Retinal color photographs centered on the optic disc and macula were captured on a digital retinal camera following dilation of the pupils. Three uveitis-subspecialized ophthalmologists assessed each pigmented retinal lesion, and complete concordance of opinion was required to assign a toxoplasmic etiology. Serum T. gondii immunoglobulin (Ig)G levels were measured for those participants with retinal lesions judged to be toxoplasmic retinochoroiditis.

MAIN OUTCOME MEASURES

Prevalence of toxoplasmic retinochoroiditis.

RESULTS

Eight participants (0.16%) had retinal lesions that were considered to have the characteristic appearance of toxoplasmic retinochoroiditis, plus detectable serum T. gondii IgG, consistent with the diagnosis of toxoplasmic retinochoroiditis. On the assumption that 23.81% of retinal lesions occur at the posterior pole, as reported in a community-based survey conducted in Brazil (Sci Rep. 2021;11:3420), the prevalence of toxoplasmic retinochoroiditis was estimated at 0.67% or 1 per 149 persons.

CONCLUSIONS

Toxoplasmic retinochoroiditis is common in Australian adults. Efforts to quantify and address risk factors for human infection with T. gondii are justified.

Cryptococcus gattii endogenous chorioretinitis

Purpose

To present a case of subretinal abscess associated with pneumonia and meningitis caused by Cryptococcus gattii in an immunocompetent host.

Observations

A 37-year-old man presented with sub-acute painless unilateral vision loss and a white submacular elevation. Systemic evaluation revealed a lung lesion and cerebrospinal fluid evidence of Cryptococcus gattii infection.

Conclusions and importance

While Crypococcus neoformans has been well described as a cause of chorioretinitis in immunocompetent and immunocompromised hosts, this report demonstrates that Cryptocuccus gattii is a related uncommon pathogen to be considered in similar presentations. Submacular surgical debridement may be challenging and OCT imaging may be helpful to detect full-thickness retinal necrosis.

Infectious Uveitis in Horses and New Insights in Its Leptospiral Biofilm-Related Pathogenesis

Uveitis is a sight-threatening eye disease in equids known worldwide that leads to considerable pain and suffering. By far the most common type of uveitis in Germany and neighboring countries is classical equine recurrent uveitis (ERU), which is caused by chronic intraocular leptospiral infection and is the main cause of infectious uveitis in horses. Other infectious causes are extremely rare and are usually clinically distinguishable from ERU. ERU can be treated very effectively by vitreous cavity lavage (vitrectomy). For proper indications of this demanding surgery, it is necessary to differentiate ERU from other types of uveitis in which vitrectomy is not helpful. This can be conducted on the basis of anamnesis in combination with ophthalmologic findings and by aqueous humor examination. During vitrectomy, vitreous material is obtained. These vitreous samples have historically been used for numerous etiologic studies. In this way, a chronic intraocular leptospiral infection has been shown to be the cause of typical ERU and, among other findings, ERU has also been recognized as a biofilm infection, providing new insights into the pathogenesis of ERU and explaining some thus far unexplainable phenomena of ERU. ERU may not only have transmissible aspects to some types of uveitis in humans but may also serve as a model for a spontaneously occurring biofilm infection. Vitreous material obtained during therapeutically indicated vitrectomy can be used for further studies on in vivo biofilm formation, biofilm composition and possible therapeutic approaches.

Clinical features and long-term treatment outcomes in choroidal tuberculoma

PURPOSE

To investigate the clinical features and treatment outcomes of patients with choroidal tuberculoma.

METHODS

In this retrospective, observational case series, the medical records of five patients with choroidal tuberculoma who were followed up at a university hospital for at least 6 months were analyzed.

RESULTS

Of five patients, one was male and four were female. The overall mean age was 38.0 ± 9.4 years (mean follow-up: 41.2 ± 33.8 months). Tuberculin skin test was performed in three patients, and it was positive in two of them. Interferon-gamma assay was performed in two patients and was positive in all two. Three patients had systemic tuberculosis involving the lung or other organs. Five patients were treated with antitubercular therapy for a period of 9.6 ± 8.6 months. Systemic corticosteroid treatment was performed in 3 patients, with a period of 3.5 ± 0.7 months. One patient with a recurrent vascularized tuberculoma was successfully treated with single intravitreal bevacizumab injection.

CONCLUSION

Choroidal tuberculoma can develop without evidence of systemic tuberculosis and can recur despite antitubercular treatment. High index of suspicion is important in early detection, and management of choroidal tuberculoma. In cases of suspected choroidal tuberculoma, positive results on immunological tests would be sufficient to initiate antitubercular therapy even if radiological evidence of systemic tuberculosis is not found. Antitubercular therapy combined with systemic corticosteroids provided favorable results. Intravitreal injection of anti-vascular endothelial growth factor may be considered for highly vascularized choroidal tuberculoma.

Cytologic analysis of vitreous fluids: A retrospective review of our 24 years of experience

BACKGROUND

Cytologic analysis of vitreous fluid is an important component in diagnosis of vitreitis. No standard reporting guidelines exist for these specimens. This study chronicles our 24 years experience and proposes a tentative diagnostic model.

METHODS

Retrospective cytology reports review and database study. Clinical indications, cytologic patterns, ancillary studies performed, and diagnoses were recorded.

RESULTS

176 samples from 160 patients were included and main cytologic patterns are reflected in Table 1. Most fluids were negative for malignancy (88%) and patterns IIB (53%) and IIA (19%) were dominant. The non-diagnostic rate was 7%; atypical and suspicious categories represented <0.5% of fluids tested and only 2% were positive for malignancy (3 intraocular lymphoma and one melanoma). Clinical indications for fluid examination were infection/inflammation (59%), to rule out lymphoma (11%), amyloidosis (3%), melanoma (2%), or to investigate intraocular hemorrhage. Fungal elements were demonstrated in 7 cases. No viral inclusions were appreciated; however, one case was positive for HSV 2 by IHC and 2 were negative by PCR. One case had Gram + cocci. Flow cytometry studies were suboptimal in 6 fluids, negative for an aberrant lymphocyte population in 11, and positive for high grade lymphoma in 3 cases. Atypical, suspicious and positive for melanoma were reported in 3 samples. Amyloid was identified in 1 aspirate.

CONCLUSIONS

Cytologic analysis of vitreous fluid is a useful tool. Modern techniques like flow cytometry and PCR testing further expand the diagnostic possibilities. Standardization of diagnostic terminology will aid clinicians caring for patients suffering from ocular disease.

Hypopyon: Is-it Infective or Noninfective?

Hypopyon usually corresponds to the sedimentation of white blood cells, and it signifies severe intraocular inflammation. This key clinical sign may occur in association with a wide variety of infectious, inflammatory, and neoplastic conditions that may be sight- and, occasionally, life-threatening. A careful history and thorough clinical examination are the cornerstones for orienting the differential diagnosis, identifying the causative agent, and initiating prompt and appropriate treatment. This review outlines the clinical characteristics and management of hypopyon in relation with the underlying causative infectious or noninfectious ocular or systemic diseases.

Viral Loads in Ocular Fluids of Acute Retinal Necrosis Eyes Infected by Varicella-Zoster Virus Treated with Intravenous Acyclovir Treatment

Acute retinal necrosis (ARN) is a rare viral endophthalmitis, and human herpesvirus is the principal pathogen. Early diagnosis and treatment are critical to avoid visual impairment by ARN, and pars plana vitrectomy (PPV) is required in advanced cases. In this study, we evaluated the transition of viral load in ocular fluids of ARN eyes with varicella-zoster virus (VZV) after intravenous acyclovir treatment. Fourteen eyes of 13 patients were analyzed retrospectively. All patients received intravenous acyclovir treatment, and eventually, all eyes underwent PPV. A polymerase chain reaction (PCR) test showed a 100% detection rate in all aqueous humor samples collected before the treatment (Pre-AH), as well as aqueous humor (Post-AH) and vitreous fluid samples (VF), collected during PPV conducted after the treatment. Within eight days or less of acyclovir treatment, viral loads both in AH and VF did not decrease significantly. Furthermore, the viral load of Pre-AH had a strong correlation with that of VH. These data suggest that in ARN eyes with VZV infection, the AH sample for the PCR test was reliable to confirm the pathogen. We propose that short-term treatment of intravenous acyclovir may be insufficient for reducing intraocular viral load, and the Pre-AH sample could be a predictor of viral activity in the eyes after acyclovir treatment.

Usefulness of aqueous and vitreous humor analysis in infectious uveitis

OBJECTIVE

To evaluate the role of intraocular fluid analysis as a diagnostic aid for uveitis.

METHODS

Twenty-eight samples (27 patients including 3 HIV-infected patients) with active (n=24) or non-active (n=4) uveitis were submitted to aqueous (AH; n=12) or vitreous humor (VH) analysis (n=16). All samples were analyzed by quantitative PCR for herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV), Epstein-Barr virus (EBV) and Toxoplasma gondii.

RESULTS

The positivity of the PCR in AH was 41.7% (5/12), with 50% (2/4) in immunocompetent and 67% (2/3) in HIV+ patients. The positivity of the PCR in VH was 31.2% (5/16), with 13% (1/8) in immunocompetent and 50% (4/8) in immunosuppressed HIV negative patients. The analysis was a determinant in the diagnostic definition in 58% of HA and 50% of VH.

CONCLUSION

Even in posterior uveitis, initial AH analysis may be helpful. A careful formulation of possible clinical diagnosis seems to increase the chance of intraocular sample analysis being meaningful.

[Pharmacological treatment strategies and surgical options for uveitis]

BACKGROUND

Modern treatment of uveitis aims at a complete control of inflammatory activity, preservation of visual function and the prevention of secondary organ damage as a consequence of the underlying inflammatory disease and its treatment.

OBJECTIVE

This article gives an update about the strategies of pharmacological and surgical options for uveitis.

MATERIAL AND METHODS

The outcomes reported here are based on a PubMed search using the terms <"uveitis" AND "therapy"> and <"uveitis" AND "surgery" OR "surgical treatment">. All prospective studies and case series with more than 20 cases as well as review articles from the last 5 years along with cited cross-references were evaluated.

RESULTS

Local and systemic corticosteroids form the foundation of treatment after exclusion of an infectious etiology. If uveitis activity is not controlled within 6 weeks or if the daily corticosteroid dosage is unacceptably high, a treatment escalation using immunomodulatory drugs is required. If a complete control of inflammatory activity is not achieved, in a third phase treatment is supplemented by antibody-based treatment or cytokines, so-called biologics, with the aim of complete long-term freedom from disease without local or systemic steroid treatment. This target is achieved in 65-80% and guarantees long-term functional stability and anatomical integrity. Early treatment escalation in cases of persisting or recurrent activity as a rule prevents new secondary organ damage. Surgical options are utilized for diagnostic purposes, the administration of intravitreal drugs and for treatment of secondary complications.

CONCLUSION

Just like the majority of immunological diseases, uveitis is a chronic disease requiring long-term and possibly lifelong treatment and remission (absence of inflammation without treatment) is achieved in only <20%. Surgical interventions can be performed with a good prognosis, if the optic nerve head and macula are not involved. They have a substantially lower complication rate when freedom from symptoms exists preoperatively for at least 3 months.

Intraocular Biopsy and ImmunoMolecular Pathology for "Unmasking" Intraocular Inflammatory Diseases

Intraocular inflammation can hide a variety of eye pathologies. In 33% of cases, to obtain a correct diagnosis, investigation of the intraocular sample is necessary. The combined analyses of the intraocular biopsy, using immuno-pathology and molecular biology, point to resolve the diagnostic dilemmas in those cases where history, clinical tests, and ophthalmic and systemic examinations are inconclusive. In such situations, the teamwork between the ophthalmologist and the molecular pathologist is critically important to discriminate between autoimmune diseases, infections, and intraocular tumors, including lymphoma and metastases, especially in those clinical settings known as masquerade syndromes. This comprehensive review focuses on the diagnostic use of intraocular biopsy and highlights its potential to enhance research in the field. It describes the different surgical techniques of obtaining the biopsy, risks, and complication rates. The review is organized according to the anatomical site of the sample: I. anterior chamber containing aqueous humor, II. iris and ciliary body, III. vitreous, and IV. choroid and retina. We have excluded the literature concerning biopsy for choroidal melanoma and retinoblastoma, as this is a specialized area more relevant to ocular oncology.

Diagnosis of Vitreoretinal Aspergillosis with Transvitreal Retinochoroidal Biopsy

Diagnosing culture-proven endophthalmitis is complicated by the insufficient yield of intraocular samples and the variety of etiologies which mimic true endophthalmitis. In cases of impending vision loss where vitreous biopsy cannot provide a definitive diagnosis, transvitreal retinochoroidal biopsy can be an effective next step. Our case is a 48-year-old male with B-cell acute lymphoblastic leukemia that presented with counting fingers vision, redness, and tearing of the left eye. Exam showed cell and flare with hypopyon as well as dense vitritis. The patient underwent diagnostic pars plana vitrectomy and vitreous culture was negative at the time. Flow cytometry demonstrated no malignant cells. However, the patient's vision and mental status continued to clinically decline despite being started on intravitreal and systemic antibiotic and antifungal therapy. Neuroimaging revealed rim-enhancing brain lesions. Transvitreal retinochoroidal biopsy was performed in an elevated area of the retina. The biopsy helped rule out malignancy and showed acute-angle, septate, branching hyphae characteristic of Aspergillus fumigatus. Ultimately, the vitreous biopsy, cultures, and a biopsy from the left frontal lobe brain abscess all confirmed this diagnosis as well. Transvitreal retinochoroidal biopsy can play a role in the diagnosis of a case of posterior uveitis and can be particularly effective in diagnosing a fungal endophthalmitis.

ULTRASOUND IN VITRECTOMY: An Alternative Approach to Traditional Vitrectomy Techniques

PURPOSE

To study a prototype of an ultrasound-based vitrector, and to try to understand the physical phenomena underlying this new technology.

METHODS

We tested the ultrasound-based vitrector prototype (UV) (ultrasonically-driven handpiece obtained from a modified version of the Alcon CONSTELLATION Vision System [Alcon]) using an automatic experimental setup. Balanced saline solution (BSS) and vitreous (from fresh postmortem enucleated porcine eyes) flow rates were analyzed using three different tips.

RESULTS

In general, BSS solution flow rates increased with increasing aspiration levels and decreased when we used % US power. Vitreous flow rates were influenced by aspiration levels, % US power, and ultrasound-related phenomena: cavitation phenomenon and "jet streaming."

CONCLUSION

Ultrasound-based vitrectomy may represent an important alternative to traditional vitrectomy. Such a tool, capable of liquefying and excising the vitreous body using ultrasound, could overcome all the limits of the guillotine-based technique (GV). Knowledge of the physical phenomena underlying ultrasound-based technology is a necessary prerequisite for further development of this new technology.

A Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2018 Update by the Infectious Diseases Society of America and the American Society for Microbiology

The critical nature of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician/advanced practice provider and the microbiologists who provide enormous value to the healthcare team. This document, developed by experts in laboratory and adult and pediatric clinical medicine, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. This document presents a system-based approach rather than specimen-based approach, and includes bloodstream and cardiovascular system infections, central nervous system infections, ocular infections, soft tissue infections of the head and neck, upper and lower respiratory infections, infections of the gastrointestinal tract, intra-abdominal infections, bone and joint infections, urinary tract infections, genital infections, and other skin and soft tissue infections; or into etiologic agent groups, including arthropod-borne infections, viral syndromes, and blood and tissue parasite infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. In addition, the pediatric needs of specimen management are also emphasized. There is intentional redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a guidance for physicians in choosing tests that will aid them to quickly and accurately diagnose infectious diseases in their patients.

Retinitis associated with double infection of Epstein-Barr virus and varicella-zoster virus: A case report

RATIONALE

Chronic uveitis with immunosuppressive agents could develop chronic herpetic retinitis with varicella-zoster virus (VZV) or herpes simplex virus (HSV). Ocular Epstein-Barr virus (EBV) infection develops uveitis and vitritis, but the clinical feature of EBV retinitis is not typical as a viral retinitis. EBV retinitis is rare, and only a few cases of EBV retinitis have been reported. Herein, we describe a case of retinitis with EBV and VZV which were the primary viruses verified by multiplex polymerase chain reaction (PCR).

PATIENT CONCERNS

A 75-year-old woman suffered from sudden visual loss in the left eye. She had been diagnosed with rheumatoid arthritis. At presentation, visual acuity (VA) was 20/400 in the left eye. Slit lamp examination disclosed fine white keratic precipitates with infiltrating cells and dense vitreous opacities in the anterior segment and vitreous. Fundus photographs showed multifocal chorioretinal scars in macula and peripheral retina, and granular lesions surrounding arcade vessels.

DIAGNOSES

Ocular toxoplasmosis was primarily suspected.

INTERVENTIONS

However, serological test showed negative of toxoplasmosis. Therefore, a diagnostic and therapeutic vitrectomy was performed. Vitreous fluid sample was used for multiplex PCR for detection of human herpesvirus (HHV) -1 to -8, toxoplasmosis and toxocariasis.

OUTCOMES

Multiplex PCR detected 5.8 × 10 copies/mL of EBV-deoxyribonucleic acid (DNA), and 3.6 × 10 copies/mL of VZV-DNA in the sample. Therefore, we could diagnose the unidentified panuveitis a retinitis associated with double infection of EBV and VZV. At 85 days after the vitrectomy, VA of the left eye recovered to be 20/16.

LESSONS

Elderly patients under immunosuppression may be susceptible to develop retinitis associated with infection of multiple HHVs, and multiplex PCR is an excellent tool to diagnose an unidentified panuveitis resembling this case.

Development and evaluation of multiplex real-time PCR for diagnosis of HSV-1, VZV, CMV, and Toxoplasma gondii in patients with infectious uveitis

Infectious uveitis is a vision threatening inflammatory ocular disease wherein early diagnosis may prevent the loss of vision. The purpose of this study was to develop a multiplex real-time PCR for the diagnosis of Herpes simplex virus-1, Varicella zoster virus, cytomegalovirus and Toxoplasma gondii in patients with suspected infectious uveitis. A total of 126 intraocular samples (aqueous and vitreous humor) were collected and subjected to multiplex real-time PCR. Overall 26.2% (33/126) patients were found to be positive for one or more of the pathogens tested. The overall positivity for VZV, HSV, CMV and T. gondii was found to be 16 (12.7%), 7 (5.6%), 5 (3.9%), and 9 (7.1%); with mean pathogen load of 5.07×10⁵, 9.5×10⁴, 1.08×10⁴ and 394 (copies/μl) respectively. The development of highly sensitive and specific assay for early differentiation of pathogens is important for the early initiation of treatment thereby preventing irreversible damage to the ocular structures.

Cytopathology of Vitreous Humor Samples in Routine Practice

OBJECTIVE

To describe findings in vitreous fluid samples in routine cytology practice.

STUDY DESIGN

The pathology archives from 1988 to 2008 at our institution were searched for vitreous samples. The slides were reviewed and clinical and follow-up information was obtained.

RESULTS

One hundred and eighty-two vitreous fluid samples from 166 patients were analyzed. Most of the samples had been collected for vitreous hemorrhage (75 cases). The second reason for vitreous sample cytological evaluation was an intraocular inflammatory process (55 cases). A specific cause of inflammation was found by combining clinical, microbiological and cytopathological findings in 19 cases, i.e. infection in 7, sarcoidosis in 3, retinal necrosis in 3, lens-induced endophthalmitis in 2, uveitis associated with systemic disease in 2, retrobulbar neuritis in 1 and sympathetic ophthalmia in 1. Among the 19 samples from 16 patients collected to rule out malignancy, 8 had a confirmed intraocular malignancy. Malignant cells were observed in 5 cases (3 lymphomas, 1 melanoma and 1 carcinoma). Undiagnosed malignancies included 2 lymphomas and 1 choroidal melanoma. Other samples were collected during surgery for retinal detachment and cataracts.

CONCLUSIONS

In routine practice, cytology of the vitreous fluid is performed in many and varied situations that are most often nonneoplastic. In nonneoplastic cases, cytology is a useful adjunct to vitrectomy, in spite of its limitations.