Salim Ben Yahia

New Infectious Etiologies for Posterior Uveitis

Emergent and resurgent arthropod vector-borne diseases are major causes of systemic morbidity and death and expanding worldwide. Among them, viral and bacterial agents including West Nile virus, Dengue fever, Chikungunya, Rift Valley fever, and rickettsioses have been recently associated with an array of ocular manifestations. These include anterior uveitis, retinitis, chorioretinitis, retinal vasculitis and optic nerve involvement. Proper clinical diagnosis of any of these infectious diseases is based on epidemiological data, history, systemic symptoms and signs, and the pattern of ocular involvement. The diagnosis is usually confirmed by the detection of a specific antibody in serum. Ocular involvement associated with emergent infections usually has a self-limited course, but it can result in persistent visual impairment. There is currently no proven specific treatment for arboviral diseases, and therapy is mostly supportive. Vaccination for humans against these viruses is still in the research phase. Doxycycline is the treatment of choice for rickettsial diseases. Prevention, including public measures to reduce the number of mosquitoes and personal protection, remains the mainstay for arthropod vector disease control. Influenza A (H1N1) virus was responsible for a pandemic human influenza in 2009, and was recently associated with various posterior segment changes.

Pattern of uveitis in Behçet’s disease in a referral center in Tunisia, North Africa

The purpose of this study was to analyze the pattern of uveitis in Behçet’s disease in Tunisia, North Africa. We retrospectively reviewed the clinical records of 62 patients (111 eyes) diagnosed with Behçet’s uveitis (BU) at the Department of Ophthalmology, Fattouma Bourguiba University Hospital, Monastir, Tunisia, between January 1995 and December 2006. Forty-seven of 62 patients (75.8%) were men and 15 (24.2%) were women. Mean age at onset was 29.3 years. The average follow-up was 75.6 months. The most common extraocular clinical manifestations were recurrent oral ulcer in all patients and pseudofolliculitis in 52 patients (83.9%). Uveitis was bilateral in 79%. Initial best-corrected visual acuity was ≥20/40 in 41 affected eyes (36.9%) and <20/200 in 49 affected eyes (44.2%). Panuveitis (68 eyes, 61.3%) and posterior uveitis (38 eyes, 34.2%) were the most common forms, followed by anterior uveitis (five eyes, 4.5%). Retinal vasculitis was found in 89 eyes (80.2%). Most common complications included posterior synechiae (32.4%), cataract (31.5%), and cystoid macular edema (19.8%). Systemic corticosteroids were administered in 58 patients (93.5%). Immunosuppressive drugs were used in 22 patients (35.5%). Fifty-six affected eyes (50.5%) had final visual acuity ≥20/40 and 34 affected eyes (30.6%) had final visual acuity <20/200. In Tunisia, BU affects predominantly young men. Bilateral panuveitis associated with retinal vasculitis was the most common ocular manifestation. More than 50% of patients maintained a visual acuity of 20/40 or better, and immunosuppressive therapy probably contributed to the improvement of visual prognosis of these patients.

HLA-B27 and HLA-B51 Determination in Tunisian Healthy Subjects and Patients with Suspected Ankylosing Spondylitis and Behçet's Disease

The aim of this retrospective study is to assess the frequency of HLA‐B27 and HLA‐B51 in healthy subjects from the center of Tunisia and to investigate their usefulness in the diagnosis of ankylosing spondylitis (AS) and Behçets disease (BD), respectively. Microlymphocytotoxicity test was used to perform serologic HLA typing in a group of 124 healthy volunteers and a group of 365 patients suffering from clinical manifestations of AS and/or BD. HLA‐B27 was found in 3.2% of healthy subjects and in 42.9% of patients with AS (P < 0.00006). HLA‐B51 is, however, found in 16.1% of healthy subjects and in 30.0% of patients with BD (P > 0.05). Unlike HLA‐B51, which seems to be as frequent in Tunisian patients with BD as in healthy subjects, HLA‐B27 is more frequent in patients with AS than in controls. This highlights the usefulness of HLA‐B27, rather than that of HLA‐B51, in the diagnosis of the respective diseases.

Pattern of Childhood-Onset Uveitis in a Referral Center in Tunisia, North Africa

Purpose: To analyze the pattern of childhood uveitis in a referral center in Tunisia, North Africa. Methods:The study included 64 patients with uveitis examined at the Department of Ophthalmology of Monastir (Tunisia) from January 1994 to July 2005. All patients had a comprehensive ocular and systemic history, including an extensive review of medical systems. Complete ophthalmic examination was performed in all cases, including best-corrected Snellen visual acuity, slit-lamp examination, applanation tonometry, and dilated fundus examination with 3-mirror lens. Standard diagnostic criteria were employed for all syndromes or entities of uveitis. Results: The mean age at onset of uveitis was 12.4 years. The male-to-female ratio was 0.68. The process was unilateral in 51.6% of patients. Mean follow-up was 43.2 months. Anterior and intermediate uveitis each represented 31.25% of cases, posterior uveitis 20.3%, and panuveitis 17.2%. Noninfectious uveitis (75%) was the most frequent type of inflammation. Idiopathic uveitis was found in 50% of patients. Infectious uveitis was responsible for 25% of the cases, with toxoplasmosis (14.1%) being the most frequent cause. Twenty percent of the patients had systemic associations; juvenile idiopathic arthritis was found in 6.25%. Ocular complications occurred in 74.7% of affected eyes, of which the most common were posterior synechiae (28.4%), cataract (17.9%), cystoid macular edema (19%), and optic disc edema (32.6%). Fifty-seven affected eyes (60%) had a final visual acuity more than 20/40 and nine (9.5%) had a final visual acuity less than 20/200. Conclusions: In a hospital population in Tunisia, a specific cause of uveitis in children was found in half the patients. Idiopathic intermediate uveitis was the leading cause of uveitis in our study, followed by idiopathic anterior uveitis and toxoplasmosis. Uveitis associated with juvenile idiopathic arthritis was rare. Visual prognosis appeared to be good.

Primary intravitreal triamcinolone acetonide for diabetic massive macular hard exudates.

Purpose: To evaluate the efficacy of intravitreal triamcinolone acetonide as treatment for massive macular hard exudates in diabetic patients. Methods: The study was a prospective, noncomparative, interventional case series of 12 eyes (12 patients) with massive hard exudates involving the fovea that had no previous focal laser treatment. A single intravitreal injection of 4 mg of triamcinolone acetonide in 0.1 mL was performed. Visual acuity and evolution of hard exudates and fluorescein leakage were assessed. Potential complications were monitored, including ocular hypertension and endophthalmitis. Results: The follow-up period ranged from 6 to 12 months (mean, 8.25 months). Visual acuity improved significantly at examinations performed 7 days (P = 0.036), 1 month (P = 0.008), 3 months (P = 0.008), and 6 months (P = 0.003) after the injection. Visual acuity improved by at least 2 Snellen lines in 4 patients (33%). However, no eyes with initial visual acuity worse than 20/100 improved to better than 20/100. Foveal hard exudates resolved completely in 6 eyes (50%) and partially in 6 eyes (50%). Fluorescein leakage decreased and a variable proportion of microaneurysms disappeared in all cases. Intraocular pressure elevation occurred in 3 eyes (25%) and was successfully treated by topical medication. No other complications, such as endophthalmitis, were recorded. Conclusion: Intravitreal injection of triamcinolone acetonide appears to be beneficial for reducing hard exudates, decreasing fluorescein leakage, and significantly improving visual acuity in patients with diabetic massive hard exudates. Visual improvement may not be important due to profound anatomical impairment caused by hard exudate deposition. Further studies with a larger number of patients are required to assess the long-term efficacy and safety and the need for retreatment.

Arthropod vector-borne uveitis in the developing world.

Arthropod vector-borne diseases are among the most important emergent infections. They include a wide variety of bacterial, viral, and parasitic diseases that are transmitted to humans by the bite of mosquito, tick, or other arthropod. Most of them are prevalent in tropical and subtropical areas, but they tend to spread into new regions mainly owing to increasing temperatures worldwide, movement of people, increasing human population densities, wider dispersal of competent vectors, and transportation of goods and animals. Numerous arthropod vector-borne diseases have been associated with uveitis (Table 1). Among them, specific diseases have recently emerged as important causes of uveitis in the developing world. They include rickettsioses, West Nile virus infection, Rift Valley fever, dengue fever, and Chikungunya. In this article, we review the epidemiologic, systemic, and ocular features of these selected arthropod-borne vector diseases relevant to the ophthalmologist.

Orbital inflammation associated with Behçet's disease.

Herein a case of a 35‐year‐old woman with a history of Behçets disease, who presented with swelling and redness of her right eye with increasing pain, is reported. Computed tomography and magnetic resonance imaging showed enlargement of the right lacrimal gland and contrast enhancement of the extraocular muscles. A diagnosis of orbital inflammation was made and the patient was treated with corticosteroids, with prompt resolution of symptoms and clinical signs. Orbital inflammation should be considered as an ophthalmic manifestation of Behçets disease.

Branch Retinal Artery Occlusion Associated with Behçet Disease

Purpose: To report 2 cases of branch retinal artery occlusion (BRAO) associated with Behçet disease (BD). Design: Small case series. Methods: Review of two patients’ charts, fluorescein angiography, and optical coherence tomography (OCT). Results: The authors report two young patients, diagnosed with BD, who developed decreased vision secondary to BRAO for the first patient and cilioretinal artery occlusion associated with branch retinal vein occlusion for the second patient. In the two cases, artery occlusion was associated with active intraocular inflammation. Conclusions: BRAO, with subsequent transient or permanent visual impairment, is an additional ocular complication of BD.

Whole Exome Sequencing Identifies Mutations in Usher Syndrome Genes in Profoundly Deaf Tunisian Patients

Usher syndrome (USH) is an autosomal recessive disorder characterized by combined deafness-blindness. It accounts for about 50% of all hereditary deafness blindness cases. Three clinical subtypes (USH1, USH2, and USH3) are described, of which USH1 is the most severe form, characterized by congenital profound deafness, constant vestibular dysfunction, and a prepubertal onset of retinitis pigmentosa. We performed whole exome sequencing in four unrelated Tunisian patients affected by apparently isolated, congenital profound deafness, with reportedly normal ocular fundus examination. Four biallelic mutations were identified in two USH1 genes: a splice acceptor site mutation, c.2283-1G>T, and a novel missense mutation, c.5434G>A (p.Glu1812Lys), in MYO7A, and two previously unreported mutations in USH1G, i.e. a frameshift mutation, c.1195_1196delAG (p.Leu399Alafs*24), and a nonsense mutation, c.52A>T (p.Lys18*). Another ophthalmological examination including optical coherence tomography actually showed the presence of retinitis pigmentosa in all the patients. Our findings provide evidence that USH is under-diagnosed in Tunisian deaf patients. Yet, early diagnosis of USH is of utmost importance because these patients should undergo cochlear implant surgery in early childhood, in anticipation of the visual loss.

Branch retinal artery occlusion associated with posterior uveitis

BackgroundThe purpose of this study is to report the clinical features and visual outcome of branch retinal artery occlusion (BRAO) associated with posterior uveitis. This is a retrospective study including the 18 eyes of 18 patients. All patients underwent a complete ophthalmic evaluation. Fundus photography, fluorescein angiography, and visual field testing were performed in all cases.ResultsDiseases associated with BRAO included active ocular toxoplasmosis in 7 patients, rickettsiosis in 4, Behçet’s uveitis in 2, West Nile virus infection in 1, idiopathic retinal vasculitis in 1, Crohn’s disease in 1, ocular tuberculosis in 1, and idiopathic retinal vasculitis, aneurysms, and neuroretinitis syndrome in 1 patient. The mean initial visual acuity was 20/50. BRAO involved the first order retinal artery in 33.3% of the eyes, the second order retinal artery in 33.3%, an arteriole in 27.8%, and a cilioretinal artery in 5.5%. The macula was involved in 44.4% of the eyes and an acute focus of retinitis or retinochoroiditis was associated to BRAO in 55.5%. Repermeabilization of the occluded artery occurred in all patients with permanent scotomas in the corresponding visual field. The mean visual acuity at last visit was 20/32.ConclusionsBRAO, with subsequent visual impairment, may occur in the eyes with posterior uveitis. Physicians should be aware of such vision-threatening complication of infectious and inflammatory eye diseases.