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Year : 2014  |  Volume : 21  |  Issue : 4  |  Page : 291-295  

Pattern of uveitis at a referral center in Iraq

Department of Ophthalmology, College of Medicine, Al-Mustansiriya University, Baghdad, Iraq

Date of Web Publication4-Oct-2014

Correspondence Address:
Faiz I Al-Shakarchi
Department of Ophthalmology, College of Medicine, Al-Mustansiriya University, Ibn Al-Haetham Teaching Eye Hospital, Baghdad
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0974-9233.142263

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Purpose: To determine the etiologies of uveitis and the causes of visual loss in uveitis patients at a referral center in Baghdad, Iraq.
Patients and Methods: A 4-year prospective study was performed at the uveitis clinic at Ibn Al-Haetham teaching eye hospital in Baghdad, Iraq. Referral cases of active uveitis were included. A complete ophthalmic examination was performed in all cases. If clinical picture did not indicate a specific etiology, patients were sent for a routine set of tests while ancillary tests were conducted when indicated.
Results: Out of 318 patients included in this study, 236 patients (74.2%) had bilateral uveitis, and 212 patients (66.7%) had non-granulomatous uveitis. Posterior uveitis was recorded in 123 cases (38.7%) followed by panuveitis in 97 cases (30.5%), anterior uveitis in 78 cases (24.5%), and intermediate uveitis in 20 cases (6.3%). A diagnosis was established in 210 cases (66%) while etiology could not be determined in the remaining 108 cases (34%). Most common infectious causes were toxoplasmosis (13.8%) and presumed ocular tuberculosis (11.4%) while most common non-infectious causes were Vogt-Koyanagi-Harada disease (12.3%), Behηet's disease (8.2%), and pars planitis (5.7%). Out of 49 eyes with irreversible blindness, macular degenerations, or scars (46.9%) and optic nerve atrophy (34.7%) were the most important causes.
Conclusion: At this referral center, toxoplasmosis and presumed ocular tuberculosis were the most common infectious causes of uveitis while Vogt-Koyanagi-Harada disease, Behηet's disease, and pars planitis were, in that order, the most common non-infectious causes. Macular degenerations or scars and optic nerve atrophy were the most important causes of irreversible blindness.

Keywords: Behçet′s Disease, Iraq, Toxoplasmosis, Tuberculosis, Uveitis

How to cite this article:
Al-Shakarchi FI. Pattern of uveitis at a referral center in Iraq . Middle East Afr J Ophthalmol 2014;21:291-5

How to cite this URL:
Al-Shakarchi FI. Pattern of uveitis at a referral center in Iraq . Middle East Afr J Ophthalmol [serial online] 2014 [cited 2022 Oct 3];21:291-5. Available from: http://www.meajo.org/text.asp?2014/21/4/291/142263

   Introduction Top

Uveitis is a sight-threatening disease, and may be associated with other systemic diseases. It is the fifth most common cause of severe visual loss in the developed world, and up to 20% of legal blindness is due to complications of uveitis. [1],[2] It may be due various infectious, immunological, and sometimes unknown agents. The etiologies of uveitis are greatly influenced by genetic, ethnic, and geographical factors. [3] Therefore, diagnostic approaches and selection of tests varies according to different populations.

In Iraq, according to a hospital-based study, uveitis is the sixth cause of legal blindness, [4] but the etiology remains undetermined. Patients with uveitis are probably sent for unnecessary laboratory tests and are at risk of receiving inadequate treatment which can result in increased morbidity and blindness.

This study was performed to determine the etiologies of uveitis and the causes of visual loss in uveitis patients at a referral center in Baghdad/Iraq.

   Patients and Methods Top

This was a prospective case series study. Ethical board approval was granted by the Scientific Committee of Ibn Al-Haetham teaching eye hospital (IAHTEH). This study was performed at the uveitis clinic at IAHTEH in Baghdad, Iraq. IAHTEH is a government eye hospital that is a secondary and tertiary referral center, and receives patient referrals from the entire country. The uveitis clinic at IAHTEH is the only referral center for uveitis in Iraq and it receives referral cases of uveitis from the outpatient-clinics in the same hospital, and from various eye centers in the country. Patients with a first episode of uveitis that responded well to treatment and some straight forward cases are usually managed by local ophthalmologists without referral to this clinic.

Successive new patients referred to the uveitis clinic at IAHTEH, from January 2007-January 2011 were enrolled in this study, if they had clinical signs of active uveitis. Cases of exogenous uveitis (post-trauma, or post-surgery), and lens-induced uveitis were excluded.

Numerous variables were assessed including age, sex, demographics, onset, course, and presence of related systemic diseases. All patients underwent a complete ocular examination, which included measurement of visual acuity, examination of the anterior segment with a slit lamp, fundus examination with indirect ophthalmoscopy, and indirect slit lamp biomicroscopy. Intraocular pressure was measured using Goldman applanation tonometry.

If clinical pictures did not indicate a specific etiology, patients were sent for a routine set of tests including: Complete blood count (CBC) with differential, erythrocytes sedimentation rate (ESR), urinalysis, chest X-ray, tuberculin skin test (T.T.), and serological tests for syphilis (fluorescent treponemal antibody absorption test). Human leucocytes antigen (HLA)-B27 typing and X-ray of sacroiliac joints were performed in cases with severe or recurrent anterior uveitis. Serological tests for Toxoplasmosis were performed in patients with compatible clinical picture to confirm the diagnosis or in posterior uveitis with hazy media obscuring a view of the fundus. Ancillary tests including fluorescein angiography, ultrasonography, magnetic resonance imaging, computed tomography, and antiphospholipid antibodies were performed as required.

Consultations were sought with an internist, a rheumatologist, or a neurologist whenever required to reach the final etiological diagnosis and for therapeutic collaboration.

The anatomical and clinical classifications of uveitis used were those given by the International Uveitis Study Group [5] and the Standardization of Uveitis Nomenclature (SUN) Working Group. [6] Cases of uveitis were classified anatomically into, anterior, intermediate, posterior, and panuveitis. Uveitis was clinically classified into: Infectious and non-infectious. The latter were subdivided into cases associated with systemic diseases and cases with specific ocular disease. The inflammation was described as acute if the onset was sudden and lasted less than 3 months, chronic if it lasted 3 months or longer, and recurrent if there were repeat episodes of inflammation separated by disease-free period(s) lasting 3 months or longer during which, patients were not on treatment.

The diagnosis of ocular toxoplasmosis was made clinically with the characteristic lesion of focal necrotizing retinochoroiditis. [7] In atypical cases, serologic tests for positive anti-Toxoplasma IgM and IgG titers supported the diagnosis while zero IgG titer excluded the diagnosis of toxoplasmosis.

Ocular tuberculosis was presumed when findings were consistent with possible intraocular tuberculosis, intractable to steroid therapy, no clinical or laboratory evidence for other causes of uveitis, and clinical response on anti tuberculosis therapy with absence of recurrences. [8],[9] Strongly positive tuberculin skin test result (more than 14 mm area of induration/necrosis) supported the diagnosis, but was not a prerequisite for initiating therapy. Patients with presumed ocular tuberculosis were sent to the Tuberculosis Institute in Baghdad, for initiating treatment with anti-tubercular therapy (ATT) (2 months of rifampicin, isoniazid, pyrazinamide, and ethambutol followed by 4 months of rifampicin and isoniazid).

Intermediate uveitis was defined as an inflammation predominantly involving the peripheral retina, the pars plana, and the anterior vitreous. In addition, vitreous cell aggregates (snowballs) and inflammatory exudates on the inferior pars plana (snowbanking) supported the diagnosis. The term pars planitis was used to describe patients who had bilateral intermediate uveitis without any specific cause. [10]

The diagnosis of Vogt-Koyanagi-Harada (VKH) disease was based on the revised diagnostic criteria. [11] While the diagnosis of Behçet's disease was based on the International Study Group Classification criteria for Behçet's disease. [12] Patients were classified as having acute retinal necrosis (ARN) based on clinical criteria formulated by the Executive Committee of the American Uveitis Society. [13] The diagnosis of herpes simplex, herpes zoster anterior uveitis, and cytomegalovirus (CMV) retinitis was based on clinical features.

Idiopathic uveitis was referred to cases with intraocular inflammation that could not be attributed to an infectious agent, an underlying systemic disease or any specific ocular cause.

   Results Top

A total of 318 consecutive patients with uveitis were included in this study. The mean age was 36.2 years, with no significant predominance in gender.

According to the type [Table 1], chronic uveitis was the most common; 233 patients (73.3%), followed by acute; 68 patients (21.4%) and recurrent uveitis; 17 patients (5.4%). Non-granulomatous uveitis was diagnosed in 212 patients (66.7%), and bilateral uveitis was diagnosed in 236 patients (74.2%). According to the anatomical classification, the most common type of uveitis was posterior uveitis; 123 cases (38.7%), followed by panuveitis; 97 cases (30.5%), anterior uveitis; 78 cases (24.5%), and intermediate uveitis; 20 cases (6.3%), respectively.
Table 1: Classification of uvesitis in 318 Iraqi patients

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According to etiology, a diagnosis was established in 210 cases (66.0%) [Table 2]. Infectious or presumed infectious origin was identified for 92 cases (28.9%) with the most important infections being toxoplasmosis and tuberculosis. Non-infectious origin was identified in 118 cases (37.1%); those associated with systemic diseases were recorded in 74 cases (23.3%), most importantly were VKH syndrome and Behçet's disease while those with primary specific clinical ocular diseases were recorded in 44 cases (13.8%), most importantly was pars planitis. Etiology could not be determined in the remaining 108 cases (34.0%) and were, thus, classified as idiopathic.
Table 2: Etiologies of uveitis in Iraqi patients

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Toxoplasmosis was the most important cause of posterior uveitis (44 patients, 45 eyes). One patient had bilateral simultaneous active toxoplasma retinitis. Positive serological test for Toxoplasma IgM antibodies were detected in the serum of seven patients and presumed to be newly acquired infection. All patients responded well to anti-toxoplasmosis therapy.

Presumed ocular tuberculosis was reported in 36 patients with panuveitis consistent with possible intraocular tuberculosis (34 cases bilateral, 2 cases unilateral). All patients had normal chest radiographs and had no evidence of active systemic disease. Strongly positive T.T. was recorded in 32 patients with presumed ocular tuberculosis while only 3 of 83 patients with other types of uveitis had strongly positive T.T. All 36 patients had a favorable response to ATT without concomitant use of systemic corticosteroids. Uveitis resolved completely within 2-6 months and did not recur for more than 1 year after completion of treatment.

VKH syndrome was diagnosed in 39 patients with bilateral panuveitis, with age ranging between 7 and 51 years. Most patients were from middle and southern governorates of Iraq.

Behçet's s disease was recorded in 26 patients with age ranging between 24 and 43 years. The majority of patients with Behçet's disease were from the northern governorates of Iraq.

Intermediate uveitis was recorded in 20 patients; two of them had systemic neurological disorders and proved to have multiple sclerosis. The other 18 patients were diagnosed as pars planitis with age ranged between 8 and 35 years.

At presentation out of 554 eyes with uveitis 175 eyes (31.6%) had visual acuity of less than counting finger at 3 meters due to complications of uveitis. Causes of blindness are listed in [Table 3], when more than one cause was presented; the more blinding cause was listed. With follow up ranging from 2-6 years (mean duration 32.2 months), 49 eyes (8.9%) had final visual acuity of less than counting finger at 3 meters. Causes of refractory blindness are listed in [Table 4]. Behçet's disease was the most important cause of bilateral blindness (5 cases), followed by T.B, CMV, and Syphilis (one case for each). While Toxoplasmosis (8 cases) was the most important cause of unilateral blindness followed by; Behçet's disease, T.B. (7 cases for each), undetermined cause (3 cases), VKH (2 cases), Syphilis, ARN, pars planitis, presumed toxocarasis, sarcodosis and sympathetic ophthalmitis (one case for each), respectively. Most cases of blinding uveitis presented late at this clinic.
Table 3: Causes of blindness in uveitis patients at presentation

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Table 4: Causes of refractory blindness in uveitis patients

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   Discussion Top

The current study was performed at the only referral center for uveitis in Iraq, and it may provide a useful data about the major causes of uveitis in this country. Posterior and panuveitis were the most common types of uveitis, in contrast to many clinic-based studies in other countries which reported that anterior uveitis is the most common form of uveitis. [14],[15] In Iraq, most cases of anterior uveitis and some other cases of uveitis are treated first by local ophthalmologists, only poor response or complicated cases were referred to the uveitis clinic. This result in a bias towards more complicated posterior and panuveitis, and this may also explain the high rate of blinding complications in cases included in this study.

In the current study, Toxoplasmosis and presumed ocular tuberculosis were the most common infectious entities while VKH, Behçet's disease, and pars planitis were the most common non-infectious causes.

Reports from neighboring countries; Saudi Arabia, [16],[17] Iran, [18] and Turkey [14] show somewhat similar causes of uveitis. Taking in consideration that VKH and T.B. are more prevalent in Saudi Arabia (south) while Behçet's disease is more prevalent in Turkey and Iran (north and east).

Toxoplasmosis is an important causes of posterior uveitis worldwide including neighboring countries. [14],[16],[17],[19] In the current study, ocular toxoplasmosis was the most common infectious uveitis and the leading cause of unilateral posterior uveitis; out of 60 cases of unilateral posterior uveitis, 43 cases (71.7%) were due to toxoplasmosis. In most patients, the diagnosis was made clinically and serological tests supported the diagnosis in atypical cases.

TB is one of the most widely distributed infectious diseases in the world, and it is endemic in Iraq. The diagnosis of ocular TB is often problematic and in nearly all reported cases, the diagnosis was only presumptive, because of the difficulty in obtaining microbiological evidence and chest X-rays are normal in cases of latent TB. [8],[9],[20] False positive T.T. can occur as the test uses a mixture of antigens from mycobacteria and some patients have already received bacille Calmette-Guerin (BCG), but the effect of BCG on T.T declines over the first 7 years after vaccination and strongly positive T.T. is unlikely to be due to prior BCG vaccination. [21] In the current study, 32 out of 36 patients with presumed ocular tuberculosis had strongly positive T.T. while only three out of 83 patients with other types of uveitis had strongly positive T.T. This gives a high sensitivity and specificity of strongly positive T.T. for ocular tuberculosis in Iraqi population (0.889 and 0.964, respectively).

Recent advances in diagnostic tools for ocular TB as detection of antibodies against purified cord factor and use of polymerase chain reaction can provide strong evidence of the infection. [22],[23]

In this study, all patients with presumed ocular tuberculosis had a favorable response on ATT without concomitant use of systemic corticosteroids, and no recurrence was recorded; this strongly favors the diagnosis of ocular tuberculosis. Oral prednisone can be added with ATT in treatment of ocular TB, in order to control coexisting inflammatory reaction, and reduce macular edema. [8]

VKH syndrome affects mainly darkly pigmented races such as Asians, Middle Eastern, and Hispanics. It is uncommon in Africans suggesting that skin pigmentation is not the sole etiological factor. [24] In the current study, VKH syndrome was the most important non-infectious cause of uveitis, and most patients were from middle and southern governorates of Iraq where Arabs (Semitic) are the predominant inhabitants.

Behçet's disease is relatively common in Iraq, as it is geographically located in an area of high incidence of Behçet's disease-the Old Silk Road. Due to ethnic factors; Behçet's disease is more common in northern governorates of Iraq where Kurds and Turkmen (Aryan) are the predominant inhabitants.

Uveitis can cause devastating visual loss and accounts for up 20% of legal blindness, [1],[2] taking in consideration that this percentage may include treatable complications of uveitis such as cataract and vitreous opacities. In the current study out of 175 eyes presenting with visual acuity less than counting fingers at 3 meters, 126 eyes (72%) had treatable complications and the vision was improved while 49 eyes (28%) ended with irreversible blindness.

   Conclusion Top

At this referral center, toxoplasmosis and presumed ocular tuberculosis were the most common infectious causes of uveitis while VKH, Behçet's disease and pars planitis were, respectively, the most common non-infectious causes. Macular degeneration or scars and optic nerve atrophy were the most important causes of irreversible blindness.

   References Top

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15.Yang P, Zhang Z, Zhou H, Li B, Huang X, Gao Y, et al. Clinical patterns and characteristics of uveitis in a tertiary center for uveitis in China. Curr Eye Res 2005;30:943-8.  Back to cited text no. 15
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  [Table 1], [Table 2], [Table 3], [Table 4]

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