Choroidal tuberculosis diagnosed by polymerase chain reaction. A clinicopathologic case report

Retinal detachment and uveitis at a tertiary center over 10 years: the King Khaled Eye Specialist Hospital (KKESH) Uveitis Survey Study Group

PURPOSE

To evaluate the frequency, etiology, treatment, and visual prognosis of retinal detachment (RD) in patients with uveitis.

METHODS

A retrospective review was performed in 707 consecutive patients (1042 eyes) with uveitis, of whom 97 (13.7%) (157 eyes [15.1%]) had RD.

RESULTS

There were 126 (12.1%) eyes with exudative retinal detachment (ERD), 16 (1.5%) with tractional retinal detachment (TRD), and 15 (1.4%) with rhegmatogenous retinal detachment (RRD). Panuveitis was most commonly associated with RD (144 (91.1%) eyes). Infectious causes were more common in RRD, and non-infectious etiologies were most common in ERD and TRD. Oral prednisone was the initial therapy in ERD. Additionally, in these cases, cyclosporine was prescribed most frequently (47.1% patients), followed by azathioprine (26.4% patients). Fourteen (87.5%) eyes with TRD and all RRD cases underwent surgery. In patients with ERD, the mean best-corrected visual acuity (BCVA) was 1.1 ± 0.7 LogMAR at baseline and 0.6 ± 0.2 LogMAR at last visit (p = 0.001). In patients with TRD, mean BCVA was 0.7 ± 0.4 LogMAR at baseline and 0.6 ± 0.4 LogMAR at last visit (p = 0.056). In patients with RRD, mean BCVA was 1.6 ± 0.9 LogMAR at baseline and 20 1.3 ± 0.9 LogMAR at last visit (p = 0.185).

CONCLUSION

In Saudi Arabia, ERD is observed in 12.1% of the eyes with uveitis, and less than 2% of eyes had TRD or RRD. Visual prognosis is usually good after ERD. Infection is the most frequent cause of RRD associated with uveitis and the visual prognosis is poor.

Tuberculous Uveitis Presenting with a Bullous Exudative Retinal Detachment: A Case Report and Systematic Literature Review

Purpose: To describe tuberculous uveitis (TU) presenting as a bullous retinal detachment (RD) and to perform a comprehensive literature review on TU with similar features. Methods: Observational case report and systematic literature review. Results: An 84-year-old woman presented with bilateral granulomatous uveitis and bullous RD in the left eye. The interferon gamma release assay was strongly positive, but all other tests were unremarkable. The patient was diagnosed with TU and started on anti-tubercular therapy (ATT) and systemic steroids with excellent treatment response. Twenty-six articles (32 cases) reported TU with exudative RD. Choroidal tuberculoma was the most common clinical manifestation, followed by optic disc edema and retinal exudate. Systemic steroids with ATT improved vision in more patients (78.6%) than ATT alone (50.0%) or oral steroids followed by ATT (50.0%). Conclusion: Atypical presentations of TU make diagnosis and treatment difficult. A high level of suspicion for TU is needed to minimize ocular morbidity.

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.

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.

Choroidoretinal granuloma in a young female patient

A 16-year-old Brazilian female patient presented with blurring of vision in the right eye. Corrected visual acuity was OD 2/20, OS 20/20. Afferent pupillary defect was absent and anterior segment examination revealed anterior uveitis. Fundus examination showed light vitritis and a raised grey-white granuloma located at posterior pole with focal serous retinal detachment on optical coherence. Indocyacnine green angiography disclosed a complete mask effect in granuloma's area. Differential diagnoses were infectious (bacterial, viral, fungal and parasites) diseases, systemic inflammatory diseases, tumours. Blood serologies (HIV, toxoplasma, Borrelia, cytomegalovirus (CMV), herpes simplex virus (HSV), varicella-zoster virus (VZV), rubeola) showed positive results for IgM and IgG for toxoplasma, and anterior chamber tap (PCR for toxoplasma, CMV, HSV, VZV) revealed toxoplasma DNA. Anti-toxoplasma therapy, pyrimethamine, sulfadiazine and calcium folinate, was administered immediately. On follow-up granuloma regression was observed, with complete visual restoration. This case demonstrates a clinically challenging posterior pole granuloma.

Tubercular retinal vasculitis

Intraocular tuberculosis (TB) infection can have different clinical manifestations including retinal vasculitis. It more frequently involves the veins and is associated with retina haemorrhages and neovascularisation. The diagnosis may be difficult and presumptive being based on clinical findings and evidence of systemic TB infection. The authors present a case of a 61-year-old woman with blurred vision and floaters in her left eye for 6 years, associated with recurrent vitreous haemorrahages. A temporal branch retinal vein occlusion was presumed. Four years later her right eye was also involved. Her best-corrected visual acuity (BCVA) was 20/50 in both eyes. Fundoscopic examination showed bilateral venous occlusion with vascular staining on fluorescein angiography suggestive of vasculitis secondary to Eales Disease (ED). The interferon gamma release assay (IGRA-QuantiFERON-TB Gold) was positive and antituberculosis treatment (ATT) was started. Her final BCVA was 20/20 bilaterally, without recurrences over a follow-up of 15 months. The use of ATT is likely to reduce recurrent vitreous haemorrhages and eliminate future recurrences.

Tubercular serpiginous-like choroiditis

Choroidal tuberculosis (TB) infection may present itself as a diffuse choroiditis that resembles serpiginous choroiditis, usually treated with immunossupressants. Recent studies have demonstrated that patients with serpiginous-like choroiditis and evidence of systemic or latent TB are best treated with antituberculosis treatment (ATT) in addition to the corticosteroid therapy. The authors present a case of a 58-year-old man with decreased vision in his left eye. His best-corrected visual acuity was 20/20 right eye and 20/200 left eye. Funduscopic examination revealed a diffuse choroiditis. Mantoux skin test showed an area of induration measuring 30×35 mm and the patient started ATT with complete resolution of retinal lesions after 2 weeks of treatment. His final visual acuity was 20/25 in the left eye with no recurrences over a follow-up of 6 months. The use of ATT in these patients is likely to reduce active inflammation and eliminate future recurrences.

Choroidal biopsy of a patient with AIDS and systemic tuberculosis: a clinicopathologic case report

PURPOSE

To report a case of Mycobacterium tuberculosis choroidal granuloma confirmed by the presence of acid-fast bacilli seen on subretinal biopsy of the choroidal lesion.

METHODS

Observational case report. A 54-year-old woman with AIDS and systemic tuberculosis reported decreased vision in the right eye for 2 months duration.

RESULTS

Subretinal biopsy showed granulomatous inflammation, and acid-fast bacilli were identified on the acid-fast bacilli stain.

CONCLUSION

In cases of presumed tuberculosis choroidal granuloma not initially responsive to tuberculosis therapy, biopsy of the choroidal mass can be beneficial to confirm the diagnosis and guide treatment.

Isolated uveal tuberculoma masquerading as an intraocular tumor in an immunocompetent patient-a clinical-pathologic study with diagnosis by PCR

Purpose

The aim of this article is to report a case of uveal tuberculoma simulating an intraocular tumor in which the diagnosis was only possible by polymerase chain reaction (PCR) analysis.

Method

This is a case report.

Results

A36-year-old male presented with a progressive growing intraocular tumor and no history or positive test for other systemic disease. The eye eventually turned blind and painful and was enucleated. Histopathologic analysis revealed a granulomatous reaction and caseation necrosis but failed to identify any causative microorganisms. Final tuberculosis diagnosis was only possible by quantitative PCR.

Conclusion

Isolated uveal tuberculoma can present in an otherwise healthy patient with negative systemic tuberculosis evaluation. PCR can be used to confirm tuberculosis when other methods have failed.

Rare presentation of definitive ocular tuberculosis in an immunocompetent young patient

Ocular tuberculosis is not uncommon ocular presentation in our community nowadays. Rare presentations described mainly in the immunocompromised patients. The diagnosis of ocular TB is presumed in the vast majority of the cases of the intraocular TB. We are presenting a very rare presentation of definitive intraocular TB in a healthy 24-year-old male.

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.

Tuberculous uveitis, a resurgent and underdiagnosed disease

BACKGROUND

Over the last decade ocular involvement due to tuberculosis has re-emerged. In non-endemic areas the low frequency of active tuberculosis is at the origin of an underestimation of the disease. The purpose of this study is to report a group of patients with presumed tuberculous uveitis and to analyse the pre-diagnostic course, the diagnostic delay and the evolution of ocular inflammation after diagnosis and anti-tuberculous treatment.

METHODS

Criteria for presumed tuberculous uveitis included the presence of a hyperpositive tuberculin skin test with compatible uveitis and the exclusion of other possible etiologies.

RESULTS

Thirty-five patients fulfilled the diagnostic criteria for presumed tuberculous uveitis and were included in the study. The diagnosis was performed at presentation in only seven patients, while the correct diagnosis was delayed in the other 30 patients. The mean diagnostic delay was 5.7 +/- 4 years. Anti-tuberculous therapy was given for a minimum of 6 to a maximum of 24 months. Post-diagnostic mean follow-up was 30.4 +/- 13.4 months. Anti-tuberculous therapy resulted in a highly significant increase in visual acuity, from 0.53 to 0.78 (P < 0.001), a highly significant decrease of recurrences, from 100 to 10% (P < 0.001), with only three recurrences observed during the follow-up, and a highly significant decrease in intra-ocular pressure, from 18.3 to 13.7 (P < 0.001).

CONCLUSIONS

Our study tends to confirm the existence of tuberculous uveitis and supports the validity of the proposed diagnostic criteria. Recognition of the correct diagnosis and specific therapy, even with substantial delay, avoids recurrences, improves visual acuity and intra-ocular inflammation and decreases intra-ocular pressure.

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.

Ocular tuberculosis masquerading as ocular tumors

Tuberculosis has re-emerged as a serious public health problem in recent years. The ocular manifestations of tuberculosis are uncommon and diverse. Occasionally, patients initially present with ocular symptoms that simulate intraocular malignancy or other inflammatory conditions. We present five patients with ocular tuberculosis who were referred with the suspicion of ocular malignancy. Four of the five patients had recently emigrated to the United States. The presenting features of these patients were panophthalmitis (one patient), endophthalmitis leading to scleral perforation (one patient), active choroidal granuloma associated with uveitis (two patients), and amelanotic choroidal lesion without inflammatory signs (one patient). Of these five cases, two had a known history of systemic tuberculosis, while the ocular findings in the other three cases were the presenting manifestation of systemic tuberculosis. Multi-drug antituberculous regimen were employed in all cases for a mean of 9 months (median 6 months, range 6-12 months). Three patients responded well to therapy with salvage of the globe and the two remaining patients underwent primary enucleation for blind painful eye or perforated eye. In conclusion, ocular tuberculosis can have variable clinical manifestations and occasionally appears as an intraocular or epibulbar tumor. A high degree of clinical suspicion is important, especially in immigrants from developing countries.

Subretinal Fluid Analysis in the Diagnosis of Choroidal Tuberculosis

BACKGROUND

Diagnosis of intraocular tuberculosis is often difficult. A choroidal granulomalike lesion suspected to be the result of tuberculosis could be of other inflammatory, infective, or neoplastic causes. We report two cases in which a choroidal granuloma with exudative retinal detachment was diagnosed as tuberculosis by the detection of acid-fast bacilli in subretinal fluid.

METHODS

Interventional case series.

RESULTS

Two female patients had choroidal granulomas with surrounding exudative retinal detachment. Detailed laboratory investigations were unhelpful in diagnosis, and the patients' conditions worsened with systemic steroid therapy. Subretinal fluid was tapped and revealed acid-fast bacilli and grew Mycobacterium tuberculosis on culture.

CONCLUSION

Subretinal fluid analysis can help in the detection of tuberculous granuloma and facilitate successful management.

Presumed tubercular serpiginouslike choroiditis: clinical presentations and management

PURPOSE

Choroiditis, choroidal tubercles, and tuberculomas are well known ocular manifestations of systemic tuberculosis. The present series aimed to report the occurrence of serpiginouslike choroiditis of presumed tubercular origin.

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Eleven eyes in seven consecutive patients with a diagnosis of choroidal tuberculosis simulating serpiginous choroiditis were studied between 1997 and 2000. TESTING AND INTERVENTION: All patients had their fundus photographs taken at the time of initial presentation as well as during follow-up. All patients underwent a Mantoux skin test and chest radiography. In addition, five patients had their aqueous or vitreous humor subjected to polymerase chain reaction (PCR) for Mycobacterium tuberculosis. Sputum examination, biopsy, or both were carried out whenever recommended by the pulmonologist. Systemic antituberculosis chemotherapy was instituted in combination with treatment for ocular inflammation.

MAIN OUTCOME MEASURE

Therapeutic response and visual improvement.

RESULTS

There were five men and two women ranging in age from 17 to 32 years. Clinical presentations included three morphologic variants; multifocal progressive choroiditis showing wavelike progression to confluent, diffuse lesions resembling serpiginous choroiditis (three eyes); diffuse choroiditis characterized by diffuse plaquelike choroiditis with an amoeboid pattern suggestive of serpiginous choroiditis at initial presentation (four eyes); and mixed variety where opposite eyes had mixed features (four eyes). All patients had strongly positive Mantoux skin test results and positive chest radiograph results. The PCR results from aqueous and vitreous humor in four samples was positive for Mycobacterium tuberculosis; one had sputum positive for acid-fast bacilli, whereas two had histopathologic evidence of tuberculosis from cervical or parahilar lymph nodes. Treatment was associated with resolution of choroidal lesions and visual improvement. Final visual acuity of 20/30 or better was achieved in five eyes.

CONCLUSIONS

Choroidal tuberculosis may present as multifocal progressive or diffuse choroiditis resembling serpiginous choroiditis. It is important to recognize these presentations because these eyes show good response to systemic antituberculosis chemotherapy.

Rhegmatogenous retinal detachment and uveitis

PURPOSE

To evaluate the frequency, high-risk factors, and visual prognosis of rhegmatogenous retinal detachment (RRD) in patients with uveitis.

DESIGN

Retrospective case-control study.

PARTICIPANTS

We included 1387 consecutive patients with uveitis who consulted our uveitis clinic from January 1990 through December 1997 of whom 43 patients (46 eyes) with RRD were identified. The retinal detachment (RD) controls were 212 consecutive patients with RRD (221 eyes, first occurrence of RD, not associated with uveitis) who were admitted for surgery in the period from April 1999 to April 2000. The uveitis control group consisted of 150 age-matched patients (210 eyes) selected from the entire uveitis series.

INTERVENTION

Retrospective analysis of clinical data.

MAIN OUTCOME MEASURES

The presence of RRD and eventual risk factors for RRD, such as myopia, retinal lattice degeneration, prior intraocular surgery, anatomic location of uveitis, its specific diagnosis, and clinical manifestations. Furthermore, the surgical and nonsurgical outcomes of RRD, as well as the results of various treatment regimens, were analyzed.

RESULTS

RRD was identified in 3.1% of the patients with uveitis. RRD was most frequently associated with panuveitis (6.6%). RRD was associated more frequently with infectious (7.6%) than noninfectious uveitis (2.1%). At the onset of RRD, uveitis was active in most (46%) affected eyes. Proliferative vitreoretinopathy was present in 30% of the uveitic RRD eyes at presentation in contrast to 12% of the RRD control eyes. In uveitic RRD, the retina was reattached in 59% of eyes with a single operation; the final anatomic reattachment rate was 88%. Finally, a visual acuity of less than 20/200 was present in 71% of the uveitic RRD eyes, 10% of which had no light perception.

CONCLUSIONS

We discovered a high prevalence of RRD in patients with active panuveitis and infectious uveitis and document that uveitis in itself is a risk factor for the development of RRD. The visual prognosis of RRD in uveitis was poor because of the uveitis itself and the frequent development of proliferative vitreoretinopathy.

Polymerase chain reaction based detection of fungi in infected corneas

AIMS

To evaluate a polymerase chain reaction (PCR) based assay to detect fungi in scrapings from infected corneas.

METHODS

A PCR assay was developed to amplify a portion of the fungal 18S ribosome gene. Corneal scrapings from 30 patients with presumed infectious keratitis were evaluated using this assay, as well as by standard microbiological techniques, and the results were compared. Conjunctival swabs from each patient's healthy, fellow eye were also evaluated by PCR.

RESULTS

PCR and fungal culture results matched (were both positive or both negative for fungi) in 22 (74%) of 30 scrapings from infected corneas. Three (10%) of 30 samples were PCR positive but fungal culture negative; two of these appeared clinically to represent fungal infections, and the third was clinically indeterminate. Four (13%) scrapings were positive by PCR but also by bacterial and not fungal culture. One specimen (3%) was PCR negative but fungal culture positive. Of the conjunctival swabs from each patient's healthy fellow eye, five (17%) of 30 were positive by PCR, and the opposite, infected eye of all five of these harboured a fungal infection.

CONCLUSIONS

PCR is promising as a means to diagnose fungal keratitis and offers some advantages over culture methods, including rapid analysis and the ability to analyse specimens far from where they are collected.

Tuberculin skin testing in uveitis patients and treatment of presumed intraocular tuberculosis in Japan

PURPOSE

To evaluate the results of tuberculin skin testing in Japanese patients with intraocular inflammation and to assess the outcome of treatment for presumed intraocular tuberculosis in selected patients.

DESIGN

Prospective, noncomparative, interventional case series.

PARTICIPANTS

One hundred twenty-six patients, newly referred to the Ocular Inflammation Service at the Kyorin Eye Center from April 1998 to August 2000, underwent systemic evaluation for the diagnosis and/or treatment of uveitis.

METHODS

Tuberculin skin testing with purified protein derivative was performed as part of the systemic evaluation. The diagnosis of presumed intraocular tuberculosis was made when findings were consistent with possible intraocular tuberculosis, the tuberculin skin test was positive (induration more than 10 mm), and no other cause of uveitis was suggested by symptoms, signs, or ancillary testing. Using these criteria, 10 patients were given a diagnosis of presumed intraocular tuberculosis and treated with antituberculosis therapy consisting of isoniazid, with or without rifampicin. Some of these patients also received a tapered course of oral corticosteroids after the initiation of antituberculosis treatment. None of the patients had any signs or symptoms of acquired immunodeficiency syndrome.

MAIN OUTCOME MEASURES

Visual acuity and ophthalmologic examination to assess degree of intraocular inflammation.

RESULTS

Twenty-six of the 126 patients (20.6%) had a positive tuberculin skin test result. Ten of these 26 patients (38.5%) were treated for a diagnosis of presumed intraocular tuberculosis. Nine patients had no evidence of pulmonary tuberculosis, and one patient had presumed tuberculous hilar lymphadenitis. The predominant clinical finding was choroidal or optic disc nodule in three patients, retinal vasculitis in three patients, and choroiditis in four patients. Nine patients exhibited decreased intraocular inflammation with treatment.

CONCLUSIONS

Roughly one fifth of the uveitis patients who underwent systemic evaluation had a positive tuberculin skin test result, and 9 of 10 selected skin test-positive patients with clinical findings consistent with intraocular tuberculosis had a favorable response to antituberculosis therapy. These results suggest that intraocular tuberculosis continues to be a major diagnostic consideration for uveitis patients in Japan.

Ocular tuberculosis

Despite the use of highly sensitive molecular tools, such as polymerase chain reaction, for the detection of Mycobacterium tuberculosis, ocular tuberculosis remains a subject of controversy. The diagnosis is often presumptive in the absence of ocular biopsies. Choroiditis is the most common ocular manifestation in patients with pulmonary and systemic tuberculosis. Indocyanine green angiography seems to be an interesting method to determine choroidal involvement. PCR technology is proposed to evaluate the presence of the tubercule bacillus DNA in ocular fluids and tissues when conventional microbiologic methods fail to confirm a bacterial etiology. Most of the presumed cases of ocular tuberculosis should be treated with associations of antituberculous drug, especially when a systemic steroid regimen is required.

[Mediastinoscopy in the case of recurrent uveitis]

INTRODUCTION

The authors report the case of a patient who presented for 4 years recurrent anterior uveitis accompanied by asymptomatic tuberculous mediastinal lymphadenitis.

EXEGESIS

CT scan of the chest showed the existence of mediastinal lymphadenopathy (< 1 cm). Mediastinoscopy with biopsy of the right laterotracheal lymph node was performed. The culture was positive for Mycobacterium tuberculosis, thus permitting the diagnosis of tuberculosis.

CONCLUSION

This case report stresses the advantage of extensive etiological assessment when faced with unexplained uveitis; particularly it emphasizes the importance of investigating potential tuberculosis. The existence of granulomatous uveitis, a positive skin test, the ethnic origin, and mostly results of chest CT scan, were the rationale for the use of mediastinoscopy with lymph node biopsy to help guide diagnosis.