W Mak

Cerebral infarcts complicating tuberculous meningitis.

Cerebral infarction (CI) is a serious complication of tuberculous meningitis (TBM). It can be asymptomatic or symptomatic, causing stroke. We studied 40 TBM patients. All had initial CT brain scan, CT/MRI brain scan 3 months later and urgent CT brain scan for deterioration. CI was classified into lacunar infarction (LI) or large artery infarction (LAI). Twelve (30%) had CI, in 9 (23%) it was symptomatic and in 3 (8%) silent. Seven (58%) had LAI ± LI. Eight (67%) had multiple CI. Two died from brainstem CI and 6 were dependent at 1 year. Patients with LAI might develop posterior circulation CI more frequently than those with LI only. CI is a common complication of TBM locally, with LAI and multiple CI being common. Two thirds of TBM patients complicated by CI had poor prognosis despite adjunctive dexamethasone treatment.

Abnormal diffusion tensor in nonsymptomatic familial amyotrophic lateral sclerosis with a causative superoxide dismutase 1 mutation

To determine whether diffusion abnormalities can be observed in nonsymptomatic family members with a known causative Cu/Zn superoxide dismutase mutation (asymptomatic familial amyotrophic lateral sclerosis; AFALS+SOD1) in a family with autosomal dominant familial amyotrophic lateral sclerosis (ALS) using diffusion tensor imaging (DTI).

Postictal psychosis related regional cerebral hyperperfusion

Postictal psychosis is a known complication of complex partial seizure in particular temporal lobe epilepsy. It usually runs a benign and self limiting course. A postictal phenomenon with focal cerebral hypofunction (similar to Todds palsy), rather than ongoing seizure activity, has been postulated.1 2 Surface EEG is either normal or showing non-specific slow waves.3 Hence, antipsychotic medications are prescribed instead of antiepileptic drugs. Until recently, the pathogenic mechanisms have remained unknown. In this communication, we report on two patients with postictal psychosis, during which a cerebral SPECT study showed a hyperperfusion signal over the right temporal lobe and contralateral basal ganglion. As hyperperfusion in ictal cerebral SPECT is closely linked to epileptic activities,4 our findings support a contrary explanation for postictal psychosis. Interictal SPECT and SPECT performed during postictal psychosis. (Top) A SPECT study of patient 1 showing areas of relative hyperperfusion over the right temporal neocortex (red arrows) and the left basal ganglia (blue and yellow arrows) during postictal psychosis. (Bottom) SPECT study of patient 2 showing areas of hyperperfusion over the right temporal neocortex and the left basal ganglia. Arrows indicate areas of hyperperfusion. Prolonged video-EEG telemetry study was performed in patients who underwent presurgical evaluation for epilepsy surgery. Antiepileptic drugs were withdrawn …

Knowledge of Stroke in Hong Kong Chinese

A random telephone survey on knowledge of stroke was conducted in 1,238 Hong Kong Chinese. Most respondents realized that effective treatment was available, that stroke was preventable and that it could be fatal or disabling. Sudden unilateral limb weakness, sudden speech and language disturbances, and sudden vertigo and clumsiness were better recognized than other warning symptoms of stroke. A slightly better recognition of symptoms of stroke was seen in those with a belief of knowing about stroke, providing a correct description of stroke, those with a positive household history of stroke and those with a better knowledge of potential risk factors. Most respondents would choose desirable actions if stroke was suspected in their family members or themselves. Friends and relatives, newspapers and magazines, and mass media provided the major sources of their knowledge.

Circadian Variation of Stroke Onset in Hong Kong Chinese: A Hospital-Based Study

Circadian variation of onset of transient ischaemic attack (TIA) or stroke during four 6-hourly periods starting from midnight was studied in Hong Kong Chinese patients admitted to a regional hospital between October 1996 and July 1999. The onset was classifiable into one of the 6-hourly periods in 832 of 905 patients; patients with unclassifiable onset were more likely to have lacunar infarct and less likely to have intracerebral haemorrhage (ICH). There was a significant circadian variation of onset in all strokes and TIA, TIA alone, ischaemic stroke (IS), ICH and different IS subtypes. The risk of onset was greatest between 6 a.m. and noon for IS or TIA, but between noon and 6 p.m. for ICH. There was no difference in the circadian variation between patients with and without prior TIA or stroke. This hospital-based study revealed a significant circadian variation of onset in different types and subtypes of stroke.

Bath‐related headache

Bath-related headache (BRH) is a rare primary headache syndrome. We present our experience over seven years and review all reported cases of BRH. Thirteen patients, including six from our group, are described. BRH occurred exclusively in middle-aged or elderly Oriental women (mean age 51 years, range 32-67. Hong Kong 6 cases, Taiwan 4 cases, Japan 3 cases). The typical presentation was a uniphasic cluster of severe headache recurrently triggered by bathing or other activities involving contact with water. Each attack lasted 30 min to 30 h. Onset was hyperacute, consistent with that of thunderclap headache. Reversible multisegmental cerebral vasoconstriction was found in two patients. No underlying secondary causes were identified. Response to acute treatment was generally unsatisfactory, but headache could be prevented by avoiding the specific trigger(s). BRH runs a self-limiting course; all patients remitted within three months after onset. Nimodipine may shorten the duration of illness.

Idiopathic inflammatory demyelinating disorders after acute transverse myelitis

Acute transverse myelitis (ATM) is commonly para‐infectious. Recurrent ATM occurs in connective tissue diseases (CTD), infective myelitis and idiopathic inflammatory demyelinating disorders (IIDD) including multiple sclerosis (MS) and neuromyelitis optica (NMO). Previous studies might include NMO and idiopathic recurrent transverse myelitis (IRTM) as MS. The aim was to study the outcome of patients after a first attack of idiopathic ATM. Idiopathic ATM patients over a 6‐year period were retrospectively studied. Known causes of myelopathy were excluded. Among 32 patients studied, 20 (63%) had single ATM attack upon follow up for 39–93 months, three developed recurrent ATM related to CTD (two systemic lupus erythematosus and one anti‐Ro antibody positive) and nine (28.1%) developed recurrent neuroinflammation compatible with IIDD. Among IIDD patients, three had NMO, two restricted variant of NMO, three IRTM and one classical MS. NMO, its variant and IRTM had mean spinal MRI abnormality of 3.7, 2.1 and 3.9 vertebral segments respectively while non‐recurrent ATM had 1.6 vertebral segments. Four (80%) of the five patients with NMO or its variant had poor neurological prognosis versus only one (5%) of non‐recurrent ATM patients. IRTM patients had advanced mean onset age, 62 years vs. 43 years for non‐recurrent ATM patients. In IIDD patients presenting with ATM as first attack of neuroinflammation, NMO and its variant (56%) were most frequent, then IRTM (33%), with classical MS (11%) the rarest. As long‐term treatments for NMO are different from MS, early recognition of NMO and its variant is important for prevention of serious neurological deficits.

Ischemic stroke related to intracranial branch atheromatous disease and comparison with large and small artery diseases

BACKGROUND The mechanism of ischemic stroke in intracranial branch atheromatous disease (BAD) is different from large artery atherothrombotic disease (LAD) or lacunar infarction (LACI). The concept of BAD is underused in clinical practice and research. METHODS Patients admitted over 24-months with ischemic stroke caused by atherosclerotic disease were reviewed retrospectively and classified according to radiological±clinical criteria into LAD, BAD and LACI. The BAD cases were further divided into 5 BAD syndromes. Clinical characteristics, vascular risk factors, results of vascular workup and outcome among these subgroups were compared. RESULTS 123 cases of LAD (17% of all stroke patients or 33% of all studied patients), 147 BAD (20% or 40%) and 102 LACI (14% or 27%) presented during the study period. Compared to LAD, BAD patients had milder neurological deficits, were less often diabetic and carotid stenosis was less common, while stenosis of the intracranial arteries was more frequent in BAD as compared with LACI patients. Outcome in BAD patients was intermediate between LAD and LACI. Comparisons among the BAD syndromes indicated they were homogenous conditions. CONCLUSIONS BAD is the most prevalent ischemic stroke subtype in our cohort. The homogeneity among the BAD syndromes suggests they might represent a distinctive stroke entity.

Wilson’s disease with depression and parkinsonism

Wilsons disease (WD) is an autosomal recessive disorder with reduced biliary excretion of copper plus impaired formation of ceruloplasmin, leading to copper accumulation in the liver, brain, kidney, and cornea. Clinical manifestations include liver damage, psychiatric symptoms, and neurological features. We report a 35-year-old woman with a history of deranged liver functions who had severe depression several years later and eventually presented with parkinsonian features. The underlying diagnosis is WD and family screening revealed WD in 2 other siblings. She could not tolerate penicillamine because of fever and leucopenia. While taking trientine hydrochloride and zinc sulphate, her parkinsonism improved and her depression remained in remission. WD should be considered in patients with unexplained liver function derangement or psychiatric symptoms. Early diagnosis and initiation of specific treatment are crucial in minimising any further cerebral and hepatic damage as well as securing possible improvement in organ functions.

−459C>T point mutation in 5′ non‐coding region of human GJB1 gene is linked to X‐linked Charcot‐Marie‐Tooth neuropathy

Abstract  Charcot‐Marie‐Tooth (CMT) neuropathy is inherited with genetic and clinical heterogeneity. The X‐linked form (CMTX) is linked to mutations in the GJB1 gene. However, the genotype‐phenotype correlation between variants in the non‐coding region of GJB1 gene and CMTX is unclear. We found two structural variants (−459C>T and −713G>A) in the 5′ non‐coding region of a transcript (Ref seq ID: NM_000166) of the GJB1 gene and explored its association with CMTX in two Chinese families. All family members who carried the −459C>T variant either were symptomatic or had abnormal electrophysiological studies compatible with CMTX, whereas all the non‐symptomatic family members who had normal electrophysiological studies and 10 healthy unrelated controls did not have this variant. The other variant in the 5′‐flanking region of the gene was found to be a benign polymorphism, although it had been earlier reported to be associated with CMTX in a Taiwanese family. Secondary structure prediction analysis of mutant mRNA using Mfold and RNAstructure softwares indicates that the −459C>T mutation may reduce translation efficiency of the GJB1 gene by changing its 5′‐untranslated region secondary structure and abolishing the internal ribosome entry site at the initialization of its translation in Schwann cells. Our study can help clarify the causal mutations of CMTX in the non–protein coding region of GJB1.