Bhojo A. Khealani

Cerebral venous thrombosis: a descriptive multicenter study of patients in Pakistan and Middle East

Background and Purpose— The natural history, causative factors, and outcomes of patients with cerebral venous thrombosis from Asia and Middle East have not been well described. This descriptive multicenter study describes the results for cerebral venous thrombosis patients in South Asia and the Middle East. Methods— The retrospective and prospective data of patients with radiologically confirmed cerebral venous thrombosis were collected from 4 centers located in Pakistan and United Arab Emirates. The demographic, clinical, radiological, and outcome data were recorded and analyzed. Primary outcome was death or dependency (modified Rankin score >2) at the time of hospital discharge. Results— This study included 109 patients with cerebral venous thrombosis; the presenting features most commonly being observed were headache (81%), focal motor deficits (45%), seizures (39%), and mental status changes (37%). Important predisposing factors included systemic and central nervous system infection (18%), postpartum state (17%), hyperhomocystinemia (9%), genetic thrombophilia (5%), and oral contraceptive pill use (3%). Ninety-six (67%) patients received therapeutic anticoagulation. Seven patients died and 43 had poor outcome at discharge. Focal motor deficits (OR, 2.93; 95% CI, 1.2–7.5; P=0.018) and hemorrhagic infarctions (OR, 2.81; 95% CI, 1.04–7.85; P=0.041) were independent predictors of unfavorable outcome at discharge. Hemorrhagic infarction was the most significant factor of long-term unfavorable outcome (OR, 5.87; 95% CI, 1.49–23.02; P=0.011). Conclusions— Infections and postpartum state were the most common predisposing factors for cerebral venous thrombosis in this cohort. Most patients (67%) were treated with anticoagulation therapy. Almost 50% of patients were dead or disabled at discharge.

The burden of Stroke in Pakistan

Epidemiologic literature on stroke burden, patterns of stroke is almost non existent from Pakistan. However, several hospital-based case series on the subject are available, mainly published in local medical journals. Despite the fact that true stroke incidence and prevalence of stroke in Pakistan is not known, the burden is assumed to be high because of highly prevalent stroke risk factors (hypertension, diabetes mellitus, coronary artery disease, dyslipidemia and smoking) in the community. High burden of these conventional stroke risk factors is further compounded by lack of awareness, poor compliance hence poor control, and inappropriate management/treatment practices. In addition certain risk factors like rheumatic valvular heart disease may be more prevalent in Pakistan. We reviewed the existing literature on stroke risk factors in community, the risk factor prevalence among stroke patients, patterns of stroke, out come of stroke, availability of diagnostic services/facilities related to stroke and resources for stroke care in Pakistan.

Frequency and Outcome of Carotid Atheromatous Disease in Patients With Stroke in Pakistan

Background and Purpose— Limited data exist on the frequency and outcome of carotid artery disease in Pakistan. Such information would help guide the usefulness of screening for the condition in this low-middle income health care setting. Methods— A prospective, descriptive study was conducted among 3 large teaching hospitals in Karachi, Pakistan. Patients referred for carotid Doppler ultrasound examination were included if they had experienced a stroke or TIA within the previous month. The severity and morphology of carotid disease were characterized by trained technicians using standardized criteria. Demographic and risk factor data were collected at baseline, and the outcome of patients was assessed at least 6 months later. Results— A total of 672 patients underwent bilateral carotid Doppler ultrasound (1344 carotid examinations). The findings revealed 0% to 50% stenosis in 526 (78%), 51% to 69% stenosis in 57 (8%), 70% to 99% stenosis in 82 (12%), and total occlusion in 7 patients (1%). Potentially surgically correctable disease, defined as 70% to 99% carotid artery stenosis, was present in only 79 (12%) patients, of whom 47 (60%) were ipsilateral symptomatic, 15 (20%) asymptomatic, and 17 (20%) had status unknown. Outcome information at ≥6 months follow-up was available for 36 of the 47 (76%) surgically correctable and only 4 of these patients (12%) had undergone surgical or radiological intervention (carotid endarterectomy in 3 patients and carotid stenting in 1 patient). Conclusion— The frequency of carotid artery disease of at least moderate severity is very low in patients with recent stroke or TIA and there is low utilization of high-cost, carotid intervention procedures in Pakistan. These data raise questions regarding the applicability and cost-effectiveness of routine carotid ultrasound screening in our country and similar population in Asia. The local socio-economic and clinical data do not support routine carotid Doppler ultrasound in every patient with stroke and TIA in Pakistan. Studies are warranted to determine predictors of significant carotid artery stenosis in stroke/TIA patients of our country to develop reliable stroke guidelines appropriate for local population.

The Karachi intracranial stenosis study (KISS) Protocol: An urban multicenter case-control investigation reporting the clinical, radiologic and biochemical associations of intracranial stenosis in Pakistan

BackgroundIntracranial stenosis is the most common cause of stroke among Asians. It has a poor prognosis with a high rate of recurrence. No effective medical or surgical treatment modality has been developed for the treatment of stroke due to intracranial stenosis. We aim to identify risk factors and biomarkers for intracranial stenosis and to develop techniques such as use of transcranial doppler to help diagnose intracranial stenosis in a cost-effective manner.Methods/DesignThe Karachi Intracranial Stenosis Study (KISS) is a prospective, observational, case-control study to describe the clinical features and determine the risk factors of patients with stroke due to intracranial stenosis and compare them to those with stroke due to other etiologies as well as to unaffected individuals. We plan to recruit 200 patients with stroke due to intracranial stenosis and two control groups each of 150 matched individuals. The first set of controls will include patients with ischemic stroke that is due to other atherosclerotic mechanisms specifically lacunar and cardioembolic strokes. The second group will consist of stroke free individuals. Standardized interviews will be conducted to determine demographic, medical, social, and behavioral variables along with baseline medications. Mandatory procedures for inclusion in the study are clinical confirmation of stroke by a healthcare professional within 72 hours of onset, 12 lead electrocardiogram, and neuroimaging. In addition, lipid profile, serum glucose, creatinine and HbA1C will be measured in all participants. Ancillary tests will include carotid ultrasound, transcranial doppler and magnetic resonance or computed tomography angiogram to rule out concurrent carotid disease. Echocardiogram and other additional investigations will be performed at these centers at the discretion of the regional physicians.DiscussionThe results of this study will help inform locally relevant clinical guidelines and effective public health and individual interventions.

The “eye of the tiger” sign

A 13-year-old boy presented to a pediatric clinic with progressive decreased movements. His vision had been decreasing for 8 years, and he had been unable to walk for 3 years. The patient was born to a healthy nonconsanguineous couple. His mothers pregnancy and his natal history were unremarkable

Guillain–Barré syndrome (demyelinating) six weeks after bariatric surgery: A case report and literature review

Obesity is a major health problem worldwide. Bariatric surgery has been increasingly used to manage obesity. Many acute as well as chronic neurological complications have been reported after bariatric surgery including Guillain-Barré syndrome (GBS). An autoimmune process has been postulated as the underlying pathophysiology. Most of the reported cases of GBS after bariatric surgery are of the axonal variety. Here, we report a case of a demyelinating variety of GBS in a young woman who presented with acute onset of progressive weakness and paresthesia of all limbs within six weeks after bariatric surgery. She was treated with intravenous immunoglobulin (IVIG) and rehabilitation. She had complete recovery on follow-up. We believe that onset of acute inflammatory demyelinating polyradiculoneuropathy (AIDP), which is demyelinating variety of GBS, is associated with changes in immune system after bariatric surgery.

Clinical predictors of EMG-confirmed cervical and lumbosacral radiculopathy

BACKGROUND Electromyography (EMG) for suspected cervical or lumbosacral root compression is often negative, producing expense and physical discomfort that could have been avoided. To improve patient selection for testing, we sought to identify clinical features that would accurately predict presence of radiculopathy on EMG. METHODS Adult patients consecutively evaluated for suspected cervical or lumbosacral root compression at an academic clinical neurophysiology laboratory were prospectively enrolled. Presence of clinical features suggesting root disease (neck or back pain, dermatomal pain or numbness, myotomal weakness, segmental reflex loss, and straight leg-raising) was recorded prior to testing. EMG examination to confirm root compression was conducted per standard protocols. Analysis was based on computation of sensitivity, specificity, predictive values, and accuracy. RESULTS A total of 200 patients (55% male; mean age 46.4 years; 38% suspected of cervical and 62% of lumbosacral disease) were included. EMG evidence of root disease was detected in 31% of cervical and 62% of lumbosacral referrals. Dermatomal pain was the most sensitive, and segmental reflex loss and myotomal weakness the most specific individual predictors of root disease. Combined presence of dermatomal pain or numbness with segmental reflex loss and myotomal weakness approached specificities of 78% (lumbosacral disease) and 99% (cervical disease). In all cases, myotomal weakness was the most accurate predictor of root disease. CONCLUSION The diverse symptoms and signs of cervical and lumbosacral root compression predict a positive electrodiagnosis of radiculopathy with varying degrees of accuracy, and may be used to guide patient selection for EMG testing.

123. Early denervation in patients with axonal variant of Guillan–Barré syndrome

response, and side effects were recorded. Results: Sixteen patients used methotrexate in MG. Nine were women. Age at onset for using methotrexate ranged from 21 to 78 years (mean 54.2). Time from diagnosis of MG until start of methotrexate ranged from 0 months to 24 years. Weekly dosing ranged from 5 to 25 mg. Three patients used no other immunosuppressants. Eleven patients used at least two other immunosuppressant agents since MG was diagnosed. Eight patients underwent thymectomy, (two after starting methotrexate). One patient each had the following: transient elevation of hepatic transaminases that corrected with a lower dose, nausea prompting discontinuation, and multiple myeloma. Two patients died while taking methotrexate, but both the deaths were not felt to be related to methotrexate or MG. Six patients showed clinical improvement, and ten showed no changes. Eight patients decreased their daily pyridostigmine while on methotrexate. Conclusions: Methotrexate is a safe, well tolerated, and affordable medication used in this cohort of MG patients. Future randomized, prospective trials should be undertaken to determine if methotrexate is as effective as other immunosuppressant agents currently used in MG. Dr. Rivner is a consultant to Allergan.

12. Sensory nerve action potential ratios in acute inflammatory demyelinating polyneuropathies

Introduction: Poliomyelitis involves the anterior horn cells experiencing peripheral denervation, which alters the motor unit (MU) properties. The noninvasive motor unit number index (MUNIX) method and the invasive macro electromyography (EMG) method are the two techniques used to evaluate the MU involvement. Objective: To compare the two techniques in characterizing the MU properties in prior polio. Method: MUNIX and macro EMG were performed in 50 tibial anterior (TA) muscles in 34 patients with the diagnosis of prior polio. Clinical assessment of force and muscle atrophy was performed. Results: The MUNIX and the relative macro EMG parameters showed a moderate correlation. The MUNIX for the prior polio group was decreased, compared to the age-matched control subjects by 24% on average. The elevation of themacromotor unit action potential (MUAP)amplitude for thepatientgroupcompared toagematchedcontrol subjects (relative macro MUAP amplitude) was 5.1 corresponding to an estimated loss of 61% of the neurons. However, there was a great scatter of the individual results in both groups. MUNIX and macro MUAP amplitudewere correlatedwith both force andmuscle atrophy. Conclusion: The MUNIX describes the number of MUs, regardless of the effectiveness of the reinnervation process, in contrast to the macro EMG which is reflecting the mechanism of collateral reinnervation. Pros and cons for the two techniques in characterizing the MU properties in prior polio are discussed.

13. Frequency of blink reflex abnormality in chronic inflammatory demyelinating polyneuropathy

Introduction: Poliomyelitis involves the anterior horn cells experiencing peripheral denervation, which alters the motor unit (MU) properties. The noninvasive motor unit number index (MUNIX) method and the invasive macro electromyography (EMG) method are the two techniques used to evaluate the MU involvement. Objective: To compare the two techniques in characterizing the MU properties in prior polio. Method: MUNIX and macro EMG were performed in 50 tibial anterior (TA) muscles in 34 patients with the diagnosis of prior polio. Clinical assessment of force and muscle atrophy was performed. Results: The MUNIX and the relative macro EMG parameters showed a moderate correlation. The MUNIX for the prior polio group was decreased, compared to the age-matched control subjects by 24% on average. The elevation of the macro motor unit action potential (MUAP) amplitude for the patient group compared to age matched control subjects (relative macro MUAP amplitude) was 5.1 corresponding to an estimated loss of 61% of the neurons. However, there was a great scatter of the individual results in both groups. MUNIX and macro MUAP amplitude were correlated with both force and muscle atrophy. Conclusion: The MUNIX describes the number of MUs, regardless of the effectiveness of the reinnervation process, in contrast to the macro EMG which is reflecting the mechanism of collateral reinnervation. Pros and cons for the two techniques in characterizing the MU properties in prior polio are discussed.