Nested polymerase chain reaction for Mycobacterium tuberculosis DNA detection in aqueous and vitreous of patients with uveitis

Vitreoretinal Surgery in Uveitis: From Old to New Concepts - A Review

PURPOSE

The aim of this article is to do a comprehensive literature review about the current role of pars plana vitrectomy in uveitis and in its different structural complications such as cystoid macular edema, epiretinal membrane, macular hole, and retinal detachment.

METHODS

This comprehensive literature review was performed based on a search on PubMed, BioMed Central, Science Open, and CORE databases, of relevant articles abording pars plana vitrectomy in uveitis.

DISCUSSION

Uveitis is a complex disease with multiple etiologies and pathogenic mechanisms. Therapeutic pars plana vitrectomy (PPV) may aid in uveitic structural complications such as cystoid macular edema, epiretinal membranes, macular hole, and retinal detachments even though some cases may present unpredictable visual outcomes. Diagnostic PPV with appropriate ancillary testing is also a valuable tool for the assessment and diagnosis of uveitis in a large proportion of patients.

CONCLUSION

Over the years, pars plana vitrectomy has undergone significant transformations since its invention nearly 5 decades ago, however, the quality of evidence in the literature regarding its use for uveitis has not improved in the same way. Even though some structural uveitis complications (as previously mentioned) may respond well to surgery, there is still a certain unpredictability regarding its visual outcomes. On the other hand, diagnostic vitrectomy with appropriate ancillary testing is also a valuable tool for the assessment and diagnosis of uveitis in a large proportion of patients.

Polymerase chain reaction confirmed mycobacterium tuberculosis intermediate uveitis - analysis of 22 eyes of 14 cases from a tertiary care centre in South India: a retrospective study

Background

To report the role of Polymerase Chain Reaction in confirming the diagnosis of presumed Mycobacterium Tuberculosis (MTB) Intermediate Uveitis.

Method

Retrospective analysis of 22 eyes of 14 cases of presumed tubercular intermediate uveitis wherein intraocular fluid was tested for MTB DNA by Nested & Real-time PCR, based on clinical suspicion of tubercular aetiology. QuantiFERON TB gold test and High-Resolution CT Chest were done. Patients were treated with anti-tubercular therapy with oral steroids & immunomodulators. In the study, eleven were male (79%) and three female (21%). The median age was 34 years. Nested PCR for both IS 6110 & MPB 64 was positive in 64% of the cases, IS 6110 positive in 23% and MPB 64 positive in 15%. Real-time PCR was positive in 48% of the cases. Vision improved in 33% of cases, maintained in 57%, and worsened in 10% of cases.

Conclusion

Presumed Tubercular intermediate uveitis can be confirmed by PCR of intraocular fluids. Anti-tubercular therapy with immunosuppression can improve vision and prevent recurrences in such cases.

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.

Polymerase chain reaction-proven tuberculous anterior segment mass mimicking juvenile xanthogranuloma in a child

Mass lesions arising from the anterior segment in children involving the iris and ciliary body can be of myogenic, neurogenic, or hematogenic/vascular origin. These include nevi, melanomas, adenoma, adenocarcinoma, cysts, metastatic tumours among others. Multiple iris mass lesions due to tuberculosis in children are rare. We present an uncommon atypical presentation of multiple anterior segment mass lesions referred to us as neoplasia. Although excision biopsy can be diagnostic, it was deferred and anterior chamber tap was done. Aqueous cytology was suspicious of juvenile xanthogranuloma (JXG) but polymerase chain reaction (PCR) confirmed tuberculous etiology. Treatment with antituberculous therapy (ATT) and steroids lead to complete resolution of the lesions.

Program-wide review and follow-up of erythema Induratum of Bazin and tuberculosis-associated ocular inflammation management in a TB low-incidence setting: need for improved treatment candidate selection, therapy standardization, and care collaboration

BACKGROUND

Erythema induratum of Bazin (EIB) - nodular vasculitis associated with Mycobacterium tuberculosis (TB) - and Tuberculosis-Associated Ocular Inflammation (TB-AOI) represent uncommon manifestations of TB. There is limited data and a lack of diagnostic and treatment standards for these conditions.

METHODS

Eleven-year retrospective review of EIB and TB-AOI cases managed in a provincial TB program with prospective phone-based follow-up of anti-tubercular therapy (ATT) recipients. Presumptive TB-AOI and EIB diagnoses were determined by ophthalmologist or dermatologist assessments correlated with positive tuberculin skin test and/or QuantiFERON-TB Gold, along with pathologic criteria in EIB cases.

RESULTS

Of 21 EIB and 20 TB-AOI cases that received ATT, 13 and 11, respectively, were reached for follow-up. The majority of EIB and TB-AOI cases were female and immigrated from TB high-burden countries. Median durations of pre-diagnosis symptoms were 2 and 0.8 years (IQR 2.5 & 1.1) for EIB and TB-AOI cases, respectively. Overall, 14 different ATT regimens were used for a median duration of 6 months (range 5-9). ATT related adverse events resulting in treatment discontinuation occurred in 14% of EIB and 10% of TB-AOI cases. On last follow-up, 76% of EIB and 42% of TB-AOI had improvement or resolution of disease.

CONCLUSION

EIB and TB-AOI were uncommon presentations receiving variable therapy. While treatment response was modest for EIB cases, TB-AOI cases had sub-optimal treatment outcomes. The unique diagnostic and management challenges presented by these conditions in TB low-incidence settings highlight a need for improved treatment candidate selection, therapy standardization, and cross-specialty medical collaboration.

Diminished TLR2-TLR9 mediated CD4+ T cell responses are associated with increased inflammation in intraocular tuberculosis

Intraocular tuberculosis (IOTB) is amongst the leading causes of uveitis in tropical countries. Despite reports on involvement of proinflammatory cytokines, studies on innate immune responses in disease pathogenesis are lacking. Reports from animal models and patients with pulmonary tuberculosis indicate that defects in toll like receptor (TLR)2 and TLR9 signalling predispose them to tuberculosis. In this context, we investigated the role of TLR2, TLR4 and TLR9 in generation of CD4+ T effector (Teff) cell responses during IOTB. Firstly, the cells in vitreous fluids showed lower expression of TLR2 and TLR9 in IOTB as compared to non-uveitis and non-TB uveitis groups. Next, peripheral CD4+ Teff cells of subjects with IOTB showed decreased proliferative responses and lower induction of Tregs following TLR2 and TLR9 stimulation. Further, TLR9 ligation resulted in increased IFN-γ and IL-17a but decreased expression of IL-10 and TGF-β. Lastly, lower expression of genes involved in TLR9 signalling after direct TLR9 ligation was observed in IOTB. Collectively, our results show that a subdued response to direct TLR2 and TLR9 stimulation in CD4+ T cells is associated with increased proinflammatory responses in IOTB. These findings reveal an important link between innate immune signalling and ensuing adaptive immune responses in IOTB with implications in other forms of extrapulmonary tuberculosis.

Case Study

In the developing countries, incidence of systemic tuberculosis is very high, with over 8 million new cases each year. The incidence of tuberculous uveitis is also rising correspondingly. It is difficult to diagnose ocular tuberculosis because of the lack of specific ocular findings and specific confirmatory laboratory tests. However, in a developing country like India, where the prevalence of latent tuberculosis is high, uveitis of unexplained cause not fitting into known uveitis entities, in presence of Monteux positivity, is more likely to be tubercular in origin. Hence, early diagnosis and prompt treatment with antitubercular treatment may result in dramatic drop in recurrence and improve individual patient outcomes.

Polymerase chain reaction for Mycobacterium tuberculosis DNA detection from ocular fluids in patients with various types of choroiditis in a referral eye center in India

Aims:

The aim of this study was to detect Mycobacterium tuberculosis (MTB) DNA with polymerase chain reaction (PCR) in aqueous or vitreous samples of patients suffering from choroiditis presumed to be infectious origin.

Settings and Design:

Hospital-based, retrospective case–control study.

Subjects and Methods:

In all, forty eyes of forty patients with choroiditis divided into two groups – Group A (serpiginous-like choroiditis, ampiginous choroiditis, multifocal choroiditis) and Group B (choroidal abscess, miliary tuberculosis (TB), choroidal tubercle) were analyzed retrospectively. In 27 controls (patients without uveitis undergoing phacoemulsification), anterior chamber aspirate was done and sample subjected to real-time PCR. Patients underwent nested PCR for MTB using IS6110 and MPB64 primers from aqueous (n = 39) or vitreous (n = 1). All patients underwent detailed ophthalmological examination by slit-lamp biomicroscopy, fundus examination by indirect ophthalmoscopy, and fundus photograph and fundus fluorescein angiography if required.

Statistical Analysis:

Positive results of PCR for MTB within the group and between two groups were statistically analyzed using Chi-square test.

Results:

There were 25 males and 15 females. Mean age at presentation was 34.66 years (range, 14–62). PCR positivity rates were 41.3% (n = 12/29) and 81.82% (n = 9/11) in Groups A and B, respectively. No controls had PCR-positive result. Comparison of PCR positivity rates showed statistically significant difference between Groups A and B (P = 0.028). Systemic TB was detected in 57.14% (n = 12/21) of all PCR-positive cases (Group A - 33.3%, n = 4/12; Group B - 88.9%, n = 8/9). Systemic antitubercular treatment (ATT) for 9 months and oral steroids were successful in resolution of choroiditis in all PCR-positive patients (n = 21) without disease recurrence.

Conclusions:

Eyes with choroiditis of suspected/presumed tubercular origin should be subjected to PCR for diagnosis of TB and subjected to ATT for prevention of recurrences.

Ocular Tuberculosis

Ocular tuberculosis is an extrapulmonary mycobacterial infection with variable manifestations. The reported incidence of ocular involvement varies considerably, depending on the criteria used for diagnosis and the population sampled. However, tuberculosis is thought to affect the lungs in 80% of patients, with the remaining 20% being affected in other organs, such as the eye. It is imperative for physicians to consider this diagnosis in their differential, as ocular tuberculosis can present in a fashion similar to that of more common conditions causing ocular inflammation. In addition, prompt recognition of the clinical signs and symptoms leads to quicker initiation of antituberculosis therapy.

Diagnosis of Ocular Tuberculosis

Ocular tuberculosis remains a presumptive clinical diagnosis, as the gold standard tests for diagnosing ocular tuberculosis are often not useful: Mycobacterium tuberculosis cultures require weeks to process on Lowenstein-Jenson media and have low yield from ocular samples; while acid-fast bacilli smears or polymerase chain reaction detection of M. tuberculosis DNA have low sensitivities. Thus, diagnosis is often based on suggestive clinical signs, which are supported by positive investigations: tuberculin skin test or interferon-gamma release assays; chest X-ray findings suggestive of pulmonary tuberculosis, and/or evidence of associated systemic tuberculosis infections in the absence of other underlying disease. The aim of this review is to provide an update on the methods of diagnosing ocular tuberculosis, and discuss the challenges of its diagnosis. We also suggest a step-ladder approach to a more accurate diagnosis of ocular tuberculosis by combining the available diagnostic tests.

Detection of Mycobacterium tuberculosis Genome in Subretinal Fluid of Patients with Latent Tuberculosis Infection

PURPOSE

To test our hypothesis that Mycobacterium tuberculosis (MTB) DNA may be present in retinal pigment epithelium (RPE) cells in individuals with latent tuberculosis (TB) infection.

METHODS

A total of 100 patients with rhegmatogenous retinal detachment (without any signs of endogenous uveitis in either eye) underwent pars plana vitrectomy (PPV) with internal tamponade. All were subjected to tuberculin skin test. None had manifest systemic TB disease. The subretinal fluid collected during surgery was subjected to multitargeted polymerase chain reaction (PCR) targeting three genes of MTB (IS6110, MPB64 and protein b).

RESULTS

In total, 16 patients had latent TB, of which TB PCR was positive in six patients.

CONCLUSIONS

We demonstrate presence of MTB genome in the subretinal fluid containing RPE cells from individuals with latent TB infection, who did not have any evidence of intraocular TB or manifest systemic TB disease, and suggest that MTB can be sequestrated in the RPE cells in latent TB.

Clinical presentation, treatment, and outcomes in presumed intraocular tuberculosis: experience from Newcastle upon Tyne, UK

PURPOSE

To report the clinical manifestations and treatment outcomes of patients with presumed intraocular tuberculosis (TB) seen at the Newcastle Uveitis Service, Royal Victoria Infirmary, Newcastle upon Tyne, UK over a 10-year period.

METHODS

Retrospective review of case notes.

RESULTS

A total of 21 patients were identified. Occlusive retinal vasculitis was the commonest ophthalmological presentation (12 patients). Eight patients (38%) were found to have underlying active systemic TB (four with mediastinal lymphadenopathy, three with pulmonary TB, one with cutaneous TB). Constitutional or respiratory symptoms, elevated inflammatory markers, and an abnormal chest radiograph were poor indicators of active TB. Two patients had inactive intrathoracic TB. Eleven patients had latent TB. Eighteen patients received anti-tuberculous treatment. Final visual acuity was better than or equal to initial visual acuity in 14 out of 16 patients who completed at least 6 months of standard anti-tuberculous treatment.

CONCLUSIONS

Most patients with presumed intraocular TB have latent TB, but a significant minority has hitherto undetected active TB. Our series suggests that either proven or presumed intraocular TB occurs frequently in the absence of constitutional or respiratory symptoms, elevated inflammatory markers, or an abnormal chest radiograph. A minimum of 6 months standard anti-tuberculous treatment provides good visual outcomes in the majority of patients.

Clinical spectrum of tuberculous optic neuropathy

PURPOSE

Tuberculous optic neuropathy may follow infection with Mycobacterium tuberculosis or administration of the bacille Calmette-Guerin. However, this condition is not well described in the ophthalmic literature.

METHODS

Ophthalmologists, identified through professional electronic networks or previous publications, collected standardized clinical data relating to 62 eyes of 49 patients who they had managed with tuberculous optic neuropathy.

RESULTS

Tuberculous optic neuropathy was most commonly manifested as papillitis (51.6 %), neuroretinitis (14.5 %), and optic nerve tubercle (11.3 %). Uveitis was an additional ocular morbidity in 88.7 % of eyes. In 36.7 % of patients, extraocular tuberculosis was present. The majority of patients (69.4 %) had resided in and/or traveled to an endemic area. Although initial visual acuity was 20/50 or worse in 62.9 % of 62 eyes, 76.7 % of 60 eyes followed for a median of 12 months achieved visual acuities of 20/40 or better. Visual field defects were reported for 46.8 % of eyes, but these defects recovered in 63.2 % of 19 eyes with follow-up.

CONCLUSION

Visual recovery from tuberculous optic neuropathy is common, if the diagnosis is recognized and appropriate treatment is instituted. A tuberculous etiology should be considered when evaluating optic neuropathy in persons from endemic areas.

Tuberculous uveitis

In recent years, ocular involvement due to TB has re-emerged. Tuberculous uveitis is a readily treatable disease and the consequences of delay in either ocular or systemic diagnosis can be very serious for the patient. It is important to have a high index of suspicion of the diagnosis in patients with unexplained chronic uveitis and this will be influenced by the socio-economic circumstances, family history, ethnic origin, and previous medical history of the patient. Treatment with antituberculous therapy combined with systemic corticosteroids resolves inflammation without recurrences after medical therapy.

Experimental ocular tuberculosis in guinea pigs

OBJECTIVE

To develop an animal model of intraocular tuberculosis (TB) with features of pulmonary TB and extrapulmonary dissemination to the eye.

METHODS

Hartley strain guinea pigs were infected via an aerosol route with virulent Mycobacterium tuberculosis. One group of guinea pigs was infected with a relatively low bacterial inoculum and received no treatment. A second group of guinea pigs received high-dose infection and were treated with the first-line anti-TB drugs isoniazid, rifampin, and pyrazinamide. Development of ocular TB lesions was documented by histological analysis, acid-fast staining, and real-time polymerase chain reaction for M tuberculosis DNA.

RESULTS

Untreated guinea pigs developed pulmonary and extrapulmonary TB. Ocular TB, primarily involving the uvea, developed in 5 of 12 eyes (42%). Uveal granulomatous lesions showed the presence of acid-fast organisms and M tuberculosis DNA. In treated animals, none of the 8 eyes examined revealed the presence of acid-fast organisms; however, there was mild nongranulomatous uveitis in 4 eyes.

CONCLUSIONS

Mycobacterium tuberculosis delivered via aerosol to guinea pigs results in extrapulmonary dissemination to the eye. Of significance, intraocular changes in this model include granulomatous inflammation and the presence of acid-fast organisms, as seen in human cases of ocular TB. Clinical Relevance The guinea pig model may provide greater insight into the pathogenesis of intraocular TB and assist in the development of novel modalities to treat this global infectious disease.

Applications of the polymerase chain reaction in clinical ophthalmology

Molecular biology has become a valuable component in many areas of medicine, including ophthalmology. Polymerase chain reaction (PCR) is the most widely used tool. It has proven to be a powerful technique in diagnosis and quantification of microorganisms and antibiotic resistance screening. For a growing number of ophthalmic conditions PCR testing can be conducted. It is therefore important that clinicians be knowledgeable about the indications, strengths, and limitations of the technique. The purpose of this review is to explore the current role of PCR in the diagnosis and management of eye disease.

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.

A novel identification scheme for genus Mycobacterium, M. tuberculosis complex, and seven mycobacteria species of human clinical impact

Recently, the incidence of human mycobacterial infections due to species other than M. tuberculosis has increased worldwide. Since disease control depends on appropriate antimicrobial therapy, the precise identification of these species of clinical importance has become a major public health concern. Identification of mycobacteria has been hampered because of the lack of specific, rapid, and inexpensive methods. Therefore, we aimed at designing and validating a bacterial lysate-based polymerase chain reaction identification scheme. This scheme can classify clinical isolates into: (1) the genus Mycobacterium, (2) the M. tuberculosis complex, (3) the nontuberculous mycobacteria, and (4) the species M. avium, M. intracellulare, M. abscessus, M. chelonae, M. fortuitum and M. bovis of clinical importance, and M. gordonae, the most commonly encountered nonpathogenic species in clinical laboratories. By using M. fortuitum and M. avium lysates as models, the method sensitivity was determined to be 372 pg of DNA. In a blind parallel comparison between our approach and conventional biochemical tests, both assays correctly categorized 75 patient's mycobacterial isolates. However, our approach only required 4-9 h for categorization compared with at least 15 days by conventional tests. Furthermore, our methodology could also detect M. fortuitum and M. avium from liquid cultures, after only 2 and 6 days, respectively, of incubation. Our new identification scheme is therefore sensitive, specific, rapid, and economic. Additionally, it can help to provide proper treatment to patients, to control these diseases, and to improve our knowledge of the epidemiology of mycobacteriosis, all urgently needed, particularly in developing countries.

Tuberculosis

PURPOSE OF REVIEW

The purpose of this report is to present an update on the manifestations and management of ocular tuberculosis.

RECENT FINDINGS

Tuberculosis affects one-third of the world's population. The incidence of tuberculosis has increased with the increase in the HIV infected population. Following a resurgence of the disease in the US, the incidence has recently declined. Patients may develop scleritis that can be focal, nodular or diffuse with or without keratitis. Anterior granulomatous uveitis may occur. The posterior segment reveals vitritis, choroiditis, and can mimic serpiginous choroiditis and other entities. Patients who are immunosuppressed or HIV infected may develop active mycobacterial disease in the eye leading to rapid destruction of the ocular structures. The diagnosis of ocular tuberculosis is made by isolation of Mycobacterium tuberculosis on Löwestein-Jensen medium or by PCR. The diagnosis is supported by the clinical findings, imaging techniques including optical coherence tomography, fluorescein angiography, indocyanine green and ultrasonography. Tuberculin skin test helps to confirm the diagnosis.

SUMMARY

Ocular tuberculosis may occur in the absence of pulmonary disease. Patients present with a spectrum of clinical signs. The disease may mimic several clinical entities. Early diagnosis and prompt treatment of ocular tuberculosis may prevent ocular morbidity and blindness.

Treatment of neuro-ophthalmologic manifestations of tuberculosis

In the absence of obvious pulmonary or disseminated tuberculosis, ocular and central nervous system (CNS) tuberculosis may represent a significant diagnostic challenge. Refinements in polymerase chain reaction techniques and neuroimaging have strengthened the battery of tests used to diagnose CNS and ocular tuberculosis, yet in many cases, the diagnosis remains one of exclusion; it may ultimately be determined through exacerbation by anti-inflammatory therapy with subsequent improvement by antitubercular medication treatment. Because of emerging drug resistance, at least a two-drug regimen is required for therapeutic testing and treatment of isolated ocular tuberculosis. If pulmonary or miliary disease coexists, a 6-month, four-drug regimen with isoniazid, rifampin, pyrazinamide, and ethambutol is required for treatment. Tubercular meningitis is treated with the same four-drug regimen for at least 9 to 12 months. Burden of therapeutic compliance rests on the treating physician and public health sector. Best compliance is realized with directly observed therapy.

Tuberculosis: an under-diagnosed aetiological agent in uveitis with an effective treatment

PURPOSE

To highlight the diversity of clinical presentations with tubercular uveitis in a nonendemic setting, and discuss the diagnostic approach and an effective treatment.

METHOD

Descriptive case series.

RESULTS

A total of 12 cases of varied presentations of tubercular uveitis diagnosed over a period of 1 year of which six cases are described in detail. Presentations included choroidal tuberculomas, multifocal choroiditis, recurrent granulomatous uveitis, panuveitis with cystoid macular oedema, and serpiginous choroiditis. All cases had a chronic or recurrent course and responded very well to antitubercular treatment. Diagnosis was mainly assisted by positive tuberculin testing.

CONCLUSION

A high index of suspicion helps diagnose ocular tuberculosis in areas of low prevalence of the disease. It forms part of the differential diagnosis of any chronic or recurrent uveitis, especially in an at-risk patient. Antitubercular treatment seems highly effective.

Macular edema as the only ocular finding of tuberculosis

PURPOSE

To describe an infrequent presentation of ocular tuberculosis.

DESIGN

Retrospective observational case report.

METHODS

A 61-year-old woman presented with decreased vision in her right eye and cystoid macular edema resistant to periocular corticosteroid treatment. There were no other findings.

RESULTS

Diagnosis of probable underlying tuberculosis uveitis with macular edema as the only ocular manifestation was established based on a clinical history of possible tuberculosis during her infancy. Additionally, there were residual findings in the patient's chest x-ray, a positive Mantoux reaction, and Mycobacterium tuberculosis in sputum. Specific treatment was implemented for nine months. Cystoid macular edema resolved completely, visual acuity improved (20/20), and no remission occurred during two years of follow-up.

CONCLUSIONS

In cases of idiopathic cystoid macular edema, tuberculosis should be considered as a potential cause. When treated, both are curable.