Novel mutations in typical and atypical genetic loci through exome sequencing in autosomal recessive cerebellar ataxia families

Nearly a thousand mutations mapping to 60 different loci have been identified in cerebellar ataxias. However, almost 50% of the cases remain genetically uncharacterized and there is a difference in prevalence as well as in the phenotypic spectrum of ataxia among various geographical regions. This poses a challenge for setting up a genetic panel for screening ataxia. In our ataxic cohort of 1014 families, 61% are genetically uncharacterized (UC). We investigated the potential of whole exome sequencing in conjunction with homozygosity mapping (HM) to delineate the genetic defects in three uncharacterized families with recessive inheritance each manifesting some unusual phenotype: (i) infantile onset ataxia with hearing loss (IOAH), (ii) Juvenile onset cerebellar ataxia with seizures (JCS) and (iii) Friedreich ataxia-like (FA-like). We identified a novel missense mutation in c10orf2 in the family with IOAH, compound heterozygous mutations in CLN6 in the family with JCS and a homozygous frame-shift mutation in SACS in the FA-like patient. Phenotypes observed in our families were concordant with reported phenotypes of known mutations in the same genes thus obviating the need for functional validation. Our study revealed novel variations in three genes, c10orf2, CLN6, and SACS, that have so far not been reported in India. This study also demonstrates the utility of whole exome screening in clinics for early diagnosis.

Need for a national epilepsy control program

This article briefly outlines the proposed national epilepsy control program. The content of the article is based on four meetings held by invitation of the Ministry of Health. Invitees by ministry – Drs. D. C. Jain, M. Gourie Devi, V. Saxena, S. Jain, P. Satish. Chandra, M. Gupta, K. Bala, V. Puri, K. S. Anand, S. Gulati, S. Johri, P. S. Chandra, M. Behari, K. Radhakrishnan, D. Bachani. Presentations were made by Dr. M. Tripathi.The program will involve all neurologists across the country in teaching and training at state levels and a central monitoring committee.

Clinical speech impairment in Parkinson's disease, progressive supranuclear palsy, and multiple system atrophy

CONTEXT

Speech abnormalities are common to the three Parkinsonian syndromes, namely Parkinson's disease (PD), progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), the nature and severity of which is of clinical interest and diagnostic value.

AIM

To evaluate the clinical pattern of speech impairment in patients with PD, PSP and MSA and to identify significant differences on quantitative speech parameters when compared to controls.

DESIGN AND SETTING

Cross-sectional study conducted in a tertiary medical teaching institute.

MATERIALS AND METHODS

Twenty-two patients with PD, 18 patients with PSP and 20 patients with MSA and 10 age-matched healthy controls were recruited over a period of 1.5 years. The patients were clinically evaluated for the presence and characteristics of dysarthria. This was followed by quantitative assessment of three parameters: maximum phonation time (MPT), semantic fluency and reading speed. The outcome measures were compared between the patient groups and with controls.

RESULTS

Patients with PD had hypophonic monotonous speech with occasional rushes of speech while patients with MSA and PSP had mixed dysarthria with ataxic and spastic elements respectively. All quantitative parameters were affected when compared to controls (P values<0.001, 0.012 and 0.008 respectively). Maximum phonation time was significantly less in PSP when compared to MSA and PD (P=0.015). Reading speed also showed a similar trend which was not statistically significant. Semantic fluency was comparable in all three groups.

CONCLUSION

Dysarthria in PD, PSP and MSA have many overlapping but certain distinctive features as well which could serve as a diagnostic clue. Patients with PSP had profound speech impairment probably indicative of the more severe frontostriatial pathology.

Hyperacute thrombolysis with IV rtPA of acute ischemic stroke: Efficacy and safety profile of 54 patients at a tertiary referral center in a developing country

BACKGROUND

Given the constraints of resources, thrombolysis for acute ischemic stroke (AIS) is under evaluation in developing countries. Prothrombin time (PT), platelet count and activated partial thromboplastin time (aPTT) may not be feasible within the time window.

AIM

To evaluate the safety and efficacy of thrombolysis in selected patients without the coagulation profile.

DESIGN

Open, nonrandomized, observational study.

MATERIALS AND METHODS

Fifty-four stroke patients were classified using TOAST criteria (large artery atherosclerotic = 13; cardioembolic = 12; small vessel occlusion = 22; other determined etiology =three; undetermined etiology = four). The mean time to reach emergency was 2.4h (1.15-3.4), the mean door to CT, 24 min (10-47) and the door to recombinant tissue plasminogen activator (r-tPA) injection, 26.8 min (25-67). The NIHSS scores ranged from 11 to 22 (mean = 15.5 +/- 2.7). Patients with history of liver or renal disease or those on anticoagulants were excluded. The PT, aPTT and platelet count were not done. Recombinant tissue plasminogen activator was administered at a dosage of 0.9 mg/Kg.

RESULTS

Thirty-five patients (65%) significantly improved on NIHSS at 48 h (> or =4 points) (mean change = 10; range= 4-17). At one month, 43 (79%) improved on Barthel Index (mean change = 45%). One each developed small frontal lobe hemorrhage and recurrent stroke; one died of aspiration; and eight showed no improvement.

CONCLUSIONS

Hyperacute thrombolysis was found useful and safe in selected patients with AIS even without the coagulation studies.

Role of CSF serology in follow-up of subacute Sclerosing Panencephalitis patients on treatment

Subacute sclerosing panencephalitis (SSPE) is a progressive inflammatory disease of the central nervous system with poor prognosis and high mortality. No effective treatment has a proven role; oral isoprinosine and intrathecal administration of alpha-interferon may prolong survival. We report an unusual case of adult onset SSPE patient on treatment with significant clinical improvement, even in the absence of conversion to seronegativity in either CSF or serum, on follow-up serological examination.

Quantitative thermal sensory testing in patients with monomelic amyotrophy

BACKGROUND

Quantitative thermal sensory testing (QST) is a non-invasive method to assess somatic small fibre dysfunction, which is not evaluated with routine nerve conduction studies (NCS). Monomelic amyotrophy (MMA), is a pure motor disorder with no sensory abnormalities on routine NCS, and has not been evaluated using QST.

AIMS AND OBJECTIVE

Present study aimed to evaluate somatic small fibre involvement in MMA patients. Forty patients with MMA with no sensory abnormalities or routine NCS were evaluated using QST for thresholds of cold sensation (CS), warm sensation (WS), cold pain (CP) and warm pain (WP), using method of limits. These were compared with 40 age-matched controls.

RESULTS

No abnormalities in thresholds for CS, WS, CP and WP were found in MMA group as compared to controls.

CONCLUSION

QST thus failed to demonstrate any abnormality. Hence we conclude that MMA is a pure motor disorder, with no involvement of somatic small sensory fibres (A delta and C).

Widespread electromyographic abnormalities in patients with monomelic amyotrophy: a detailed EMG study

OBJECTIVE

To evaluate subclinical electromyographic changes in unaffected muscles of the patients with monomelic amyotrophy (MMA).

PATIENTS AND METHODS

35 patients of MMA with single limb atrophy (30 patients with upper limb involvement and 5 patients with lower limb involvement) were studied at All India Institute of Medical Sciences, New Dellhi, from September 2000 to September 2002. All the patients were evaluated clinically, by detailed three limb electromyography (EMG) and by MRI scan of the spine to rule out other disorders.

RESULTS

The mean age of 35 male patients was 24.17 (+/-6.8) years and the mean duration of illness was 3.64 (+/-2.7) years. Patients with upper limb involvement had segmental pattern of atrophy, predominantly distal or proximal. EMG revealed evidence of subclinical diffuse chronic reinnervative changes. All the patients (100%) had bilateral chronic reinnervative changes and 50% had chronic reinnervative changes in three limbs.

CONCLUSIONS

Patients with clinically single limb MMA were found to have evidence of widespread chronic reinnervative changes on EMG.

Quality of life in patients with Parkinson's disease

We evaluated the quality of life (QoL) in 278 Indian patients with Parkinson's disease (PD) using PDQL questionnaire, with measures various aspects of health status in PD patients including parkinsonian symptoms, systemic symptoms, social and emotional functions. Apart from demographic and treatment details parkinsonian disability and stage was assessed by Hoehn and Yahr stage, Schwab and England scale and UPDRS scores. We conclude that female gender, presence of depression, low degree of independence, higher levodopa dose (>400 mg/day) and higher UPDRS activity of daily living score have the most detrimental impact on QoL in patients with Parkinson's disease. Depression was the most significant factor impairing the QoL and it needs to be treated.

Primary AL (kappa-light chain) amyloidosis manifesting as peripheral neuropathy in a young male without increase in serum and urine immunoglobulin load: a diagnostic challenge

Primary systemic or AL amyloidosis is a multisystem disorder characterized by diffuse extracellular infiltration of a fibrillar protein of monoclonal light chain origin (AL). Majority of the patients have monoclonal immunoglobulin in serum and/or urine and some have clonal proliferation of plasma cells in their bone marrow. This disease has the widest spectrum of organ involvement, most commonly affecting the kidneys, heart and liver. Involvement of peripheral nervous system is not infrequent and may be the presenting feature of the disease process. Thus, recognition of peripheral neuropathy and affecting the kidney as an early symptom of AL amyloidosis may widen the scope for therapeutic intervention. We describe here a rare case of primary amyloidosis (AL) kappa-light chain presenting with clinical features of peripheral neuropathy and affecting the kidney and heart at an early age of 18 years, hitherto unreported in literature. The case was further interesting as it was not associated with increased serum/urine immunoglobulins or plasma cells in bone marrow. Diagnosis was confirmed using immuno-electron microscopy on sural nerve biopsy.

Erythrocyte antioxidant enzymes in Parkinson's disease

BACKGROUND & OBJECTIVES

Oxidative stress is incriminated to play a central role in the pathogenesis of Parkinson's disease (PD). Oxidative stress, to which neurons are highly susceptible, is also known to induce oxidative changes in human red blood cells (RBCs), in vivo and in vitro. Earlier studies on oxidative stress in RBCs in patients with PD have yielded controversial results claiming unaltered activity to reduced activity. Using RBC as a model, we have undertaken this study to ascertain the possibility of oxidative damage to the RBCs in PD by measuring the cytosolic antioxidant enzymes viz., superoxide dismutase (SOD), catalase (CAT) glutathione peroxidase (G-Px) and glucose-6-phosphate dehydrogenase (G6PD).

METHODS

Activities of antioxidant enzymes were measured in erythrocytes of 115 PD patients and 37 normal age-matched healthy persons as controls. Enzymes activities were correlated with age of patients, age of onset of disease, duration of disease, United Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr stage.

RESULTS

The SOD, CAT, G-Px and G6PD activities were significantly lower in patients with PD compared to the control. A significant (P<0.05) negative correlation of enzyme activities with Hoehn and Yahr stage of the disease and also with UPDRS score was found.

INTERPRETATION & CONCLUSION

Results of the present study showed involvement of oxidative stress as one of the risk factors, which can initiate and/or promote neurodegeneration in PD and was correlated to the severity of the disease.

Myasthenic crisis: a retrospective study

BACKGROUND AND OBJECTIVE

Myasthenic crisis (MC) is one of the important and common complications in the natural history of myasthenia gravis (MG). MC can be precipitated by multiple factors including deficiency or excess of the acetylcholinesterase inhibitors (AChEI). Any episode of MC is an emergency requiring aggressive therapy. We studied the demographic, clinical and treatment-related characteristics of patients who developed MC.

MATERIALS AND METHODS

A retrospective study was conducted in patients with MC admitted during a 31-month period from February 1999 to August 2001, at a tertiary care center in India.

RESULTS

Eleven patients (9.69% of the total 114 patients with MG) were admitted with 12 episodes of MC. Mean age at presentation was 39.83 + 13.18 years with male predominance. Seven patients had undergone thymectomy previously; of which 2 had postoperative MC. Six patients had thymoma. Steroid or cholinesterase inhibitor withdrawal and infections were the commonest precipitating factors for MC. Patients required ventilatory support for median 14 days. They responded to low volume of plasma exchange (PE) (mean 854 ml / day with mean 6.5 cycles per patient).

CONCLUSIONS

This report highlights that the subset of Indian patients with MG who are at risk to develop MC belong to the 3rd and 4th decade, have bulbar symptoms at presentation and are associated with thymoma. Patients with MC should have judicious drug adjustments under supervision and should be treated aggressively during impending MC.

Leigh's syndrome

A 15-month-old female child presented with sudden onset cough and hyperventilation along with evidence of metabolic acidosis. She had past history of recurrent vomiting, episodes of abnormal posturing, difficulty in deglutition and regression of milestones since 12 months of age. CT scan of the brain revealed hypodense lesions in bilateral basal ganglia and on MRI there were T2 hyperintensities in bilateral lentiform nuclei, caudate nuclei, thalamus, red nuclei and dentate nuclei. Biochemical examination revealed persistently elevated serum lactate levels with high lactate/pyruvate ratio. Resuscitative measures were of no avail and the child succumbed to the illness on the second day of admission. Neuropathological examination at autopsy demonstrated marked spongiosis, focal necrosis, endothelial proliferation, reactive astrogliosis and extensive demyelination involving bilateral basal ganglia, midbrain and spinal cord which were typical of Leigh's sub acute necrotizing encephalomyelopathy.

Threshold intensity and central motor conduction time in patients with monomelic amyotrophy: a transcranial magnetic stimulation evaluation

OBJECTIVE

To determine the Cortical threshold intensity (TI) and central motor conduction time (CMCT) in patients with monomelic amyotrophy (MMA).

METHODS

TI and CMCT were evaluated by means of transcranial magnetic stimulation in 18 patients of MMA and 12 healthy controls at the clinical neurophysiology laboratory, department of neurology, All India Institute of Medical Sciences, New Delhi.

RESULTS

The mean age of patients was 23.6 (SD 6. 7) years and of controls was 24.3 (SD 3.2) years (p > 0. 05). The mean TI in patients was 60.83% (SD 11.28) on ipsilateral and 60% (11.5%) on contralateral cortex stimulation. In controls, the mean TI was 66.67% (SD 11.5) on one side and 65% (11.87%) on contralateral cortex stimulation. There was no significant difference in the TI between these two groups (p > 0.05). The mean CMCT in patients was 8.3 (SD 1. 7) ms on ipsilateral and 9.4 (SD 1.6) ms on contralateral cortex stimulation (p > 0.05). In controls CMCT was 8.3 (SD 1.8) ms on one side and 8.6 (SD 1.4) ms on contralateral cortex stimulation. Upper limit of normal CMCT was 12.7 ms.

CONCLUSIONS

As compared to controls there was no significant abnormality in TI and CMCT was normal in all except two patients where it was marginally prolonged. This could be because of excessive loss of anterior horn cells.

Increased depressant effect of phenytoin sodium as compared to carbamazepine on cortical excitability: a transcranial magnetic evaluation

To evaluate the effect of monotherapy (phenytoin sodium (DPH) and carbamazepine (CBZ) on the threshold intensity (TI), cortical latency (CL), central conduction time (CCT), using transcranial magnetic stimulation (TMS). A single pulse transcranial magnetic stimulation was used for recording the motor-evoked potentials (MEP) from the thenar muscles of both hands, in 36 patients with well-controlled epilepsy on monotherapy, with normal EEG and imaging studies. The TI, CL, CCT and the MEP amplitude were recorded and compared with 20 healthy controls. The threshold intensity was significantly higher in patients on DPH, (P< 0.05) with a significant decrease in the MEP amplitude when compared with controls (P< 0.05). Anticonvulsants alter the excitability of human motor pathways in epileptic subjects. This effect differs among the drugs used; DPH had a greater depressant effect on the excitability than CBZ in the present study.

Neuronal stem cells

Stem cells are self regenerating multipotential cells, found in the human brain which have the potential to differentiate into neurons, astrocytes and oligodendrocytes, and to self renew sufficiently to provide adequate number of cells in the brain. Neural stem cell grafts have been studied in a variety of animal models for various diseases like metabolic disorders, muscular dystrophies, neurodegenerative disorders, spinal cord repair, brain tumors and demyelinating disease. Stem cells may be derived from autologus, allogeneic or xenogenic sources. Histocompatibility is prerequisite for transplantation of allogeneic stem cells. Fetal tissue is the best current tissue source for human neural stem cells, however ethical issues are a major concern. Thus the prospect that stem cells could potentially be used to promote neurogenesis following injury and disease may seem attractive, yet the inherent problems associated with isolation and rejection in case of stem cells from another source, the potential to form tumors and ethical issues are the major challenges.

Cortical silent period in essential tremor

BACKGROUND

Pathophysiology of essential tremor (ET) is controversial, current evidence indicating its genesis through a central oscillator and modulation by a peripheral component. Since transcranial magnetic stimulation induced silent period (SP) has been attributed mainly to intracortical inhibitory mechanisms, it has been found useful in assessing central motor disturbances.

AIMS AND OBJECTIVES

To assess if the cortically induced SP was different in ET patients as compared to age matched healthy controls.

MATERIAL AND METHODS

Twenty-four patients of ET (mean age 45.4 +/- 14.9 years) diagnosed according to criteria of Louis et al (1998) and an equal number of healthy controls (mean age 36.2 +/- 15.7 years) were recruited in the study. Cortically induced (magnetic) SP were recorded according to the standard methods described. Student's "t" test and Wilcoxon sign rank test were used for statistical analysis.

RESULTS

The mean +/- SD cortical SP in ET patients (180.75 +/- 57.11 msec) in ET patients and in controls (163.83 +/- 35.65 msec) were statistically similar (p = 0.22).

CONCLUSION

Our study shows that there is no significant difference in mean cortical SPs in patients with ET as compared to controls.

Excessive daytime sleepiness in Parkinson's disease as assessed by Epworth Sleepiness Scale (ESS)

OBJECTIVE

To assess daytime sleepiness in patients with Parkinson's disease (PD) using the Epworth Sleepiness Scale (ESS).

MATERIAL AND METHODS

One hundred and forty-nine patients with PD (126 men, 23 women) and 115 age matched controls recruited from relatives of medical staff or spouses and other family members accompanying patients to the Movement Disorder Clinic of the All India Institute of Medical Sciences in New Delhi were included in the study. An ESS score of > or =8 was considered abnormal. Data obtained were analyzed using Chi square test for categorical variables and Student's t-test for continuous variables.

RESULTS

The mean age of patients with PD was 58.37 (S.D.=10.45) years, and that of controls 56.50 (S.D.=11.45) years, with a mean duration of disease of 5.68 (S.D.=3.85) years. The mean ESS score was 4.9 (S.D.=3.63) and 2.17 (S.D.=2.54) in PD patients and controls, respectively (P<0.05). Thirty-two patients with PD (21%) had an ESS score of >8 whereas only 3% of controls scored > or =8 on the ESS (P<0.05). Higher ESS scores were associated with a higher Hoehn and Yahr (H&Y) stage of disease and higher Unified Parkinson's Disease Rating Scale (UPDRS) (part I, III and total) scores (P<0.019, P<0.013 and P<0.011, respectively).

CONCLUSION

Excessive daytime sleepiness was more common in PD patients as compared to controls. Higher ESS scores correlated significantly with higher H&Y stage and higher UPDRS (part I, III and total) scores.

Carpal tunnel syndrome after 22 years of Colle's fracture

Delayed carpal tunnel syndrome is rare. We describe the electrophysiological findings in a patient with Colle's fracture, who developed carpal tunnel syndrome 22 years after a wrist injury.

Increased cortical excitability with longer duration of Parkinson's disease as evaluated by transcranial magnetic stimulation

Transcranial Magnetic Stimulation (TMS) was used to evaluate the cortical excitability and central motor pathways in Parkinson's disease (PD) and correlate with severity and duration of disease. 19 cases of PD and 13 controls were enrolled. The threshold intensity (TI), cortical latency (CL), central conduction time (CCT), motor evoked potential amplitude (MEP) obtained with TMS were correlated with Hoehn and Yahr and duration of disease. The threshold intensity (TI) was significantly lower in patients of PD than controls. The TI in patients with PD was 53.16-/+8.4% patients and 67.1-/+21.6% in controls (p<0.05). This strongly correlated with duration of disease, TI being lower in patients with disease duration more than 5 years. There was no difference in the other TMS parameters - CL, CCT, MEP between patients and controls. Our study revealed increased excitability in PD which was related to longer duration of disease.

Peripheral silent periods in essential tremor

BACKGROUND

Pathophysiology of essential tremor (ET) is controversial. In the present study, peripherally induced silent period (SP) in ET patients is studied.

AIMS AND OBJECTIVES

To study if the peripherally induced SP was different in ET patients as compared to age matched healthy controls.

MATERIAL AND METHODS

24 patients of ET diagnosed according to diagnostic criteria of Louis et al. [Neurology 50 (1998) 1351] (mean age 45.37+/-14.86 years) and an equal number of healthy controls (mean age 36.21+/-15.72 years) were recruited for the study. Peripherally induced SP was recorded according to the methods already described. Student's t-test and Wilcoxon sign rank test were used for statistical analysis.

RESULTS

The peripheral SP was 50.29+/-50.15 and 93.04+/-35.93 ms (p=0.0014) in ET patients and controls respectively.

CONCLUSION

Our study shows that peripheral silent period is shorter in patients of ET as compared to normal individuals.

Dystonia as presenting manifestation of ataxia telangiectasia : a case report

Ataxia telangiectasia is a genetically inherited multisystem disorder with predominant feature being telangiectasia and cerebellar ataxia. In this report, a family of three siblings suffering from ataxia telangiectasia is described. The proband presented with dystonia and dystonic myoclonus, both of which are rare presenting features of ataxia telangiectasia.

Cerebral venous thrombosis in ulcerative colitis

Cerebral venous thrombosis is a rare complication of ulcerative colitis. We report a case of 29 year old male who developed superior sagittal, left lateral and sigmoid sinus thrombosis secondary to ulcerative colitis. He was successfully treated with low molecular weight heparin and steroids.

Proton MR spectroscopy of basal ganglia in Wilson's disease: case report and review of literature

Volume localized proton Magnetic Resonance Spectroscopy was carried out in both the left and right basal ganglia of three patients with clinically proven Wilson's Disease. While the untreated patient died 15 days after the spectroscopy study, the other 2 patients have been under treatment and have shown clinical improvement. The spectral features of the untreated patient were very different from those of the other two patients who were under treatment and responding. Asymmetrical changes in NAA and Cho were also observed for this patient.