The prevalence of multiple sclerosis continues to increase in Kuwait.

BACKGROUND: The national MS registry was established in 2010 to assess the change in epidemiological status. The last reported data of the prevalence and incidence in Kuwait was in 2013. OBJECTIVES: To update the prevalence and incidence rates of MS among Kuwaiti nationals. METHODS: Using the national MS registry, a cross sectional study was conducted to estimate the number of all patients diagnosed with MS and clinically isolated syndrome suggestive of MS. The diagnosis was based on the revised 2017 McDonald criteria. The population census was acquired from the Public Authority of Civil Information. RESULTS: On 30th June 2018, 1454 Kuwaiti MS patients fulfilled the diagnostic criteria. Women represented 66.8% of the analyzed cohort with female to male ratio of 2.01:1. The crude prevalence of MS was 104.88 (95% CI: 89.5-121.9) per 100,000 persons, which increased 1.6 times since 2013. Age-adjusted prevalence peaked in the 30-39 and 40-49 year age groups in both females and male, with a decreasing tendency beyond 50 years of age. The incidence of MS was 5.39 (95% CI: 4.3-6.8) per 100,000 persons. The 5-year incidence was 6.4 per 100,000, which has been stable since the last reported rate. CONCLUSION: The prevalence of MS in Kuwaiti nationals continued to increase reflecting a better case ascertainment and improved awareness and referrals across the country. However, the incidence has stabilized in the last 5 years which was mostly driven by a slight decline in newly diagnosed cases in women compared to men despite the increase in the overall female to male ratio.

Alternative diagnoses in patients referred to specialized centers for suspected MS.

OBJECTIVES: The aim of this study is to explore the frequency, type, and predictors of alternative diagnoses among patients referred with a recent diagnosis of multiple sclerosis (MS) to two specialized MS centers in the Middle East. METHODS: This is a retrospective review of a prospectively followed cohort of MS patients at 2 University specialized MS centers. All patients referred for MS were included. The final diagnosis was recorded and demographic, clinical, laboratory, electrophysiological and radiological variables were collected. RESULTS: A total of 554 patients were included in this study of which 431 were referred for diagnostic confirmation. The final diagnosis of MS was confirmed in 300 (70%), while 114 (26%) turned out to have an alternative diagnosis and 15 (3.5%) fulfilled criteria for radiologically isolated syndrome (RIS). The most common alternative diagnoses were psychogenic (16.3%), non-specific MRI white matter lesions (14.7%), NMO (9.5%), migraine (8.6%) and systemic autoimmune disorders (8.6%). The strongest predictors of a final diagnosis of MS were: younger age, presence of oligoclonal bands in the CSF, periventricular, corpus callosum, spinal (P<0.0001), or enhancing lesions (P<0.005) on MRI. CONCLUSIONS: Our study shows that 30% of patients referred for a suspicion of MS end up with a different diagnosis. The most common alternative diagnoses of MS in the Middle East are not different from what has been described in Western countries. Age, MRI and CSF findings can help with the differential diagnosis.

Optic Nerve Sheath Meningioma Masquerading as Optic Neuritis.

Optic neuritis is a common presentation of demyelinating disorders such as multiple sclerosis. It typically presents with acute painful monocular vision loss, whereas chronic optic neuropathy can be caused by compressive lesions along the anterior visual pathway, genetic, toxic, or nutritional causes. We report an unusual presentation mimicking optic neuritis, which was subsequently diagnosed as optic nerve sheath meningioma (ONSM). Misinterpretation of white matter lesions on MRI of brain and the failure to image the optic nerves at the time of acute loss of vision led to the misdiagnosis of optic neuritis in this case. A comprehensive accurate history and ordering the appropriate imaging modality remain paramount in diagnosing progressive visual deterioration.

Ganglion cell analysis in acute optic neuritis.

BACKGROUND: Optic neuritis has a diagnostic and prognostic significance in predicting the development of multiple sclerosis. Optical coherence tomography is being increasingly used to detect and monitor axonal damage in MS by measuring the retinal nerve fiber layer (RNFL). However, RNFL can be affected by edema and inflammation and obscure early axonal damage. OBJECTIVE: To study the pattern of change in the ganglion cell and inner plexiform layer compared to retinal nerve fibber layer in acute optic neuritis using spectral domain OCT. METHODS: Ten patients with acute optic neuritis were followed prospectively for 6 months with spectral domain optical coherence tomography. A group of 40 of eyes of 20 healthy controls was used for baseline comparison. RESULTS: The ganglion cell and inner plexiform layer (GCIPL) was significantly lower (thinner) at onset in patients' affected (p=0.009) eyes. Both RNFL and GCIPL were significantly lower in affected eyes at 6 months (p=0.012 and p=0.007) respectively compared to baseline. CONCLUSION: The GCIPL is probably more sensitive index of axonal loss than the RNFL in acute optic neuritis and could be a better index to detect neurodegeneration in multiple sclerosis. This can helpful in estimating early axonal loss and can potentially be used in therapeutic trials of neuroprotective drugs.

Incidence and prevalence of pediatric onset multiple sclerosis in Kuwait: 1994-2013.

OBJECTIVES: This study aimed to assess the incidence and prevalence of pediatric-onset multiple sclerosis (POMS) along with temporal and gender differentials in these estimates in Kuwait. METHODS: We identified MS patients with pediatric (age <18 years) onset between 1994 and 2013 from national MS registry. Year and gender-specific incidence rate and prevalence estimates were computed. Multivariable Poisson regression analyses of time-series cross-sectional panel data were conducted to evaluate temporal and gender related variations in yearly POMS incidence rate and prevalence. RESULTS: 122 POMS patients were identified; of which 90 (73.8%) were females. During 2013, POMS incidence rate and prevalence (per 100,000) were 2.1 and 6.0 respectively. Multivariable Poisson regression model revealed statistically significant 5% increase in POMS incidence rate (p=0.002) and 6% increase in prevalence (p<0.001) from 1994 to 2013. Furthermore, during the study period, female children were more likely to have higher POMS incidence rate (relative rate=2.9; p<0.001) and prevalence (prevalence ratio=2.8; p<0.001). CONCLUSIONS: The temporal increase and gender disparity in POMS incidence and prevalence corroborate the findings of earlier studies conducted elsewhere. Knowledge of increasing POMS burden may help in optimal planning for better management of patients in the region.

Use of fingolimod in patients with relapsing remitting multiple sclerosis in Kuwait.

BACKGROUND: Post-marketing studies are important to confirm what was established in clinical trials, and to assess the intermediate and long-term efficacy and safety. OBJECTIVE: To assess efficacy and safety of fingolimod in multiple sclerosis (MS) in Kuwait. METHODS: We retrospectively evaluated MS patients using the MS registries in 3 MS clinics. Relapsing remitting MS patients according to revised 2010 McDonald criteria who had been treated with fingolimod for at least 12 months were included. Primary endpoint was proportion of relapse-free patients at last follow-up. Secondary endpoints were mean change in EDSS and proportion of patients with MRI activity (gadolinium-enhancing or new/enlarging T2 lesions). RESULTS: 76 patients met the inclusion criteria. Mean age and mean disease duration were 34.43 and 7.82 years respectively. Mean duration of exposure to fingolimod was 18.50 months. Proportion of relapse-free patients was 77.6% at last follow-up. Mean EDSS score significantly improved (2.93 versus 1.95; p<0.0001) while 17.1% of patients continued to have MRI activity versus 77.6% at baseline (p<0.0001). Four patients stopped fingolimod due to disease breakthrough (n=3) and lymphadenitis (n=1). CONCLUSION: Fingolimod is safe and effective in reducing clinical and radiological disease activity in relapsing remitting MS patients. Our results are comparable to reported results of phase III studies.

Multifocal ERG in ethambutol associated visual loss.

AIM: To determine the anatomical site and extent of electrophysiological dysfunction in patients with ethambutol associated visual loss. METHODS: A comparative case series. Four patients with ethambutol associated visual loss underwent multifocal electroretinography (mERG). Two patients had advanced visual loss while two had early signs of toxicity. The N1-P1, N1, P1 amplitudes, N1, and P1 latencies were compared to 10 age and sex matched controls. RESULTS: mERG abnormalities were detected in the ethambutol treated patients. The N1 amplitude was significantly lower in the ethambutol treated patients than in the control group. CONCLUSION: Ethambutol is possibly toxic to the retina, and not only the optic nerve. The multifocal ERG may be of value to diagnose and monitor patients taking ethambutol.

Fractionated stereotactic radiotherapy for parasellar meningiomas: a preliminary report of visual outcomes.

BACKGROUND/AIM: Fractionated stereotactic radiotherapy (FSRT) is a new treatment for brain tumours that are close to critical structures, such as the visual apparatus. This study aims to assess the visual outcomes for patients with parasellar meningioma following FSRT. METHODS: A retrospective, non-comparative case series of 13 patients with parasellar meningiomas who were treated in one institution with FSRT between January 1995 and January 2001. RESULTS: 13 patients (26 eyes) were followed for a mean of 2 years. Visual acuity improved in four eyes (12.5%), remained stable in 18 eyes (75%), and worsened in three eyes (12.5%). Visual field improved in 15 eyes (57%), remained stable in six eyes (23%), and worsened in four eyes (15%). No adverse visual outcome occurred as a result of radiation. CONCLUSION: These preliminary findings suggest that FSRT is a safe and effective treatment for parasellar meningiomas.