Etiology of Dementia in Thai Patients

Introduction

Molecular imaging has been developed and validated in Thai patients, comprising a portion of patients in the dementia registry. This should provide a more accurate diagnosis of the etiology of dementia, which was the focus of this study.

Methods

This was a multicenter dementia study. The baseline characteristics, main presenting symptoms, and results of investigations and cognitive tests of the patients were electronically collected in the registry. Functional imaging and/or molecular imaging were performed in patients with an equivocal diagnosis of the causes of dementia, especially in atypical dementia or young onset dementia (YOD).

Results

There were 454 patients in the study. The mean age of the patients was 78 years, with 60% female. Functional imaging and/or molecular imaging were performed in 57 patients (57/454 patients, 13%). The most common cause of dementia was Alzheimer's disease (AD; 50%), followed by vascular dementia (VAD; 24%), dementia with Lewy bodies (6%), Parkinson's disease dementia (6%), frontotemporal dementia (FTD; 2.6%), progressive supranuclear palsy (2%), multiple system atrophy (0.8%), and corticobasal syndrome (0.4%). YOD accounted for 17% (77/454 patients), with a mean age of 58 years. The causes of YOD were early onset amnestic AD (44%), VAD (16%), behavioral variant FTD (8%), posterior cortical atrophy (6.5%), and logopenic variant primary progressive aphasia (5.2%).

Conclusion

AD was the most common cause of dementia in Thai patients and the distribution of other types of dementia and main presenting symptoms were similar to previous reports in Western patients; however, the proportion of YOD was higher.

Evaluation of Retinal Nerve Fiber Layer and Ganglion Cell Layer Thickness in Alzheimer's Disease Using Optical Coherence Tomography

Objective

To evaluate the feasibility of using optical coherence tomography (OCT) for the detection of Alzheimer's disease (AD), by measuring the thickness of the retinal nerve fiber layer (RNFL) and the ganglion cell layer and inner plexiform layer (GCL-IPL).

Material and Methods

This was a single-center, cross-sectional study. The study included 29 patients with AD (mean age ± standard deviation: 75.61 ± 6.24 years) and 29 healthy age- and sex-matched controls. All participants underwent cognitive evaluations using the Montreal Cognitive Assessment test. Measurements of the RNFL thickness, as well as GCL-IPL thickness, were obtained for all participants using OCT. Both RNFL and GCL-IPL parameters were adjusted for best-corrected visual acuity, hypertension, diabetes and dyslipidemia.

Results

The mean RNFL thickness was significantly thinner in the AD group than in the control group (85.24 and 90.68 µm, respectively, adjusted P=0.014). The superior quadrant was thinner in the AD group (adjusted P=0.033). The thicknesses did not differ significantly between groups for the other quadrants. The mean GCL-IPL thickness in the AD (68.81 µm) was significantly thinner than that in the controls (76.42 µm) (adjusted P=0.014). Overall, there was a negative correlation between age and mean RNFL; and between age and GCL-IPL thickness (r=-0.338, P=0.010 and r=-0.346, P=0.008, respectively).

Conclusion

The mean RNFL and GCL-IPL thicknesses were thinner in the AD group than in the control group. These findings suggest that RNFL and GCL-IPL thickness may be biological markers for AD.

Verbal adynamia in parkinsonian syndromes: behavioral correlates and neuroanatomical substrate

Verbal adynamia (impaired language generation, as during conversation) has not been assessed systematically in parkinsonian disorders. We addressed this in patients with Parkinson's dementia, progressive supranuclear palsy and corticobasal degeneration. All disease groups showed impaired verbal fluency and sentence generation versus healthy age-matched controls, after adjusting for general linguistic and executive factors. Dopaminergic stimulation in the Parkinson's group selectively improved verbal generation versus other cognitive functions. Voxel-based morphometry identified left inferior frontal and posterior superior temporal cortical correlates of verbal generation performance. Verbal adynamia warrants further evaluation as an index of language network dysfunction and dopaminergic state in parkinsonian disorders.

Trinucleotide repeat expansion of TATA-binding protein gene associated with Parkinson's disease: A Thai multicenter study

INTRODUCTION

Spinocerebellar ataxia type 17 (SCA17) is an inherited cerebellar degeneration associated with trinucleotide repeat expansions in the TATA-binding protein gene (TBP). Low-range expansions of TBP have recently been described in association with Parkinson's disease (PD). However, these low-range expansion alleles were also observed in healthy individuals. Prior distinct findings may result from reduced penetrance or age-dependent susceptibility, which may influence phenotypic expression.

METHODS

A case-control study of 456 PD patients and 374 control subjects was conducted. Data and blood samples were collected during 2008-2013. Control subjects were individuals over 65 years old without parkinsonism. Sizes of TBP trinucleotide repeats were analyzed. All available carriers of the TBP repeat of ≥40 repeats were re-examined.

RESULTS

A high prevalence of carriers of TBP repeat expansion ≥41 developed PD, mainly at an advanced age. Half of these carriers had onset after 70 years of age (range 34-84). Seven participants carried expansion alleles of ≥42, and all had PD. Fourteen participants (six patients and eight controls) carried a heterozygous 41-repeat allele. At the current mean age of 79 years and mean follow-up period of 4 years, three out of the eight control carriers of the 41-repeat allele developed PD, while none of the thirteen asymptomatic carriers of the 40-repeat allele did.

CONCLUSIONS

A high prevalence of PD was observed in carriers of low-range expansions of TBP (41-45 repeats), especially in elderly. This finding suggests that cut-off value for pathological TBP repeat expansion appear to be 41.

Analysis of SCA8, SCA10, SCA12, SCA17 and SCA19 in patients with unknown spinocerebellar ataxia: a Thai multicentre study

BACKGROUND

About 50 % of Thai patients with adult-onset spinocerebellar ataxia (SCA) was Machado-Joseph disease (MJD), SCA1, SCA2 and SCA6. The author investigated further on less common SCAs in the patients without any known mutations.

METHODS

DNA samples of 82 index patients who were genetically excluded MJD, SCA1, SCA2, SCA6, SCA7 and dentatorubro-pallidoluysian atrophy (DRPLA) were examined. Analysis of SCA8, SCA10, SCA12, SCA17 and SCA19 genes were comprehensively performed. Normal range of trinucleotide repeat expansion sizes of TATA-box-binding protein gene (TBP) were also determined in 374 control subjects.

RESULTS

Eight patients carried ≥42 CAG/CAA repeat allele in the TBP consistent with SCA17. The pathological repeat alleles ranged from 42 to 57 repeats. All patients had significant degree of cognitive dysfunction. Other non-ataxic phenotypes comprised of parkinsonism, chorea, dystonia and myoclonus. A sporadic patient carried a heterozygous 41-repeat allele developed chronic progressive cerebellar degeneration commenced at the age of 28 years. Whilst, 2 % of the control subjects (8/374) carried the 41-repeat allele. Five of the carriers were re-examined, and revealed that four of them had parkinsonism and/or cognitive impairment without cerebellar signs. Analysis of other types of SCAs was all negative.

CONCLUSIONS

This is the first study of SCA8, SCA10, SCA12, SCA17 and SCA19 in Thais. SCA17 appears to be an important cause of ataxia in Thailand. Although, the pathological cut-off point of the TBP repeat allele remains unclear, the finding suggests that the 41-repeat may be a pathological allele resulting late-onset or mild phenotype. Apart from ataxia, cognitive impairment and parkinsonism may be clinical presentations in these carriers.

Musical tasks targeting preserved and impaired functions in two dementias

Studies of musical abilities in dementia have for the most part been rather general assessments of abilities, for instance, assessing retention of music learned premorbidly. Here, we studied patients with dementias with contrasting cognitive profiles to explore specific aspects of music cognition under challenge. Patients suffered from Alzheimer's disease (AD), in which a primary impairment is in forming new declarative memories, or Lewy body disease (PD/LBD), a type of parkinsonism in which executive impairments are prominent. In the AD patients, we examined musical imagery. Behavioral and neural evidence confirms involvement of perceptual networks in imagery, and these are relatively spared in early stages of the illness. Thus, we expected patients to have relatively intact imagery in a mental pitch comparison task. For the LBD patients, we tested whether executive dysfunction would extend to music. We probed inhibitory skills by asking for a speeded pitch or timbre judgment when the irrelevant dimension was held constant or also changed. Preliminary results show that AD patients score similarly to controls in the imagery tasks, but PD/LBD patients are impaired relative to controls in suppressing some irrelevant musical dimensions, particularly when the required judgment varies from trial to trial.

The undiscovered syndrome: Macdonald Critchley's case of semantic dementia

Semantic dementia is a unique clinicopathological syndrome in the frontotemporal lobar degeneration spectrum. It is characterized by progressive and relatively selective impairment of semantic memory, associated with asymmetric antero-inferior temporal lobe atrophy. Although the syndrome became widely recognized only in the 1980s, descriptions of cases with typical features of semantic dementia have been on record for over a century. Here, we draw attention to a well documented historical case of a patient with features that would have fulfilled current consensus criteria for semantic dementia, as reconstructed from the notes made by her neurologist, Macdonald Critchley, in 1938. This case raises a number of issues concerning the nosology of the semantic dementia syndrome and the potential value of archived case material.

Delayed auditory feedback simulates features of nonfluent primary progressive aphasia

The pathophysiology of nonfluent primary progressive aphasia (nfvPPA) remains poorly understood. Here, we compared quantitatively speech parameters in patients with nfvPPA versus healthy older individuals under altered auditory feedback, which has been shown to modulate normal speech output. Patients (n = 15) and healthy volunteers (n = 17) were recorded while reading aloud under delayed auditory feedback [DAF] with latency 0, 50 or 200 ms and under DAF at 200 ms plus 0.5 octave upward pitch shift. DAF in healthy older individuals was associated with reduced speech rate and emergence of speech sound errors, particularly at latency 200 ms. Up to a third of the healthy older group under DAF showed speech slowing and frequency of speech sound errors within the range of the nfvPPA cohort. Our findings suggest that (in addition to any anterior, primary language output disorder) these key features of nfvPPA may reflect distorted speech input signal processing, as simulated by DAF. DAF may constitute a novel candidate pathophysiological model of posterior dorsal cortical language pathway dysfunction in nfvPPA.

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The pathophysiology of nonfluent progressive aphasia (nfvPPA) is poorly understood.

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Delayed auditory feedback (DAF) disrupts speech output in some normal listeners.

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We compared quantitatively speech in nvfPPA with DAF in healthy older individuals.

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Around a third of healthy older individuals under DAF developed features of nvfPPA.

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DAF is a candidate pathophysiological model of dorsal pathway dysfunction in nfvPPA.

The brain basis of musicophilia: evidence from frontotemporal lobar degeneration

Musicophilia, or abnormal craving for music, is a poorly understood phenomenon that has been associated in particular with focal degeneration of the temporal lobes. Here we addressed the brain basis of musicophilia using voxel-based morphometry (VBM) on MR volumetric brain images in a retrospectively ascertained cohort of patients meeting clinical consensus criteria for frontotemporal lobar degeneration: of 37 cases ascertained, 12 had musicophilia, and 25 did not exhibit the phenomenon. The syndrome of semantic dementia was relatively over-represented among the musicophilic subgroup. A VBM analysis revealed significantly increased regional gray matter volume in left posterior hippocampus in the musicophilic subgroup relative to the non-musicophilic group (p < 0.05 corrected for regional comparisons); at a relaxed significance threshold (p < 0.001 uncorrected across the brain volume) musicophilia was associated with additional relative sparing of regional gray matter in other temporal lobe and prefrontal areas and atrophy of gray matter in posterior parietal and orbitofrontal areas. The present findings suggest a candidate brain substrate for musicophilia as a signature of distributed network damage that may reflect a shift of hedonic processing toward more abstract (non-social) stimuli, with some specificity for particular neurodegenerative pathologies.

Phenotypic heterogeneity in a large Thai slow-channel congenital myasthenic syndrome kinship

The slow-channel congenital myasthenic syndrome (SCCMS) is an autosomal dominant neuromuscular disorder caused by mutations in different subunits of the acetylcholine receptor (AChR). We here report our clinical findings in three generations of a large Thai kinship suffering from SCCMS and trace the disease to the p.Gly153Ser mutation in the AChR α subunit. The same mutation had previously been reported only in Caucasian but not in Asian patients. The clinical features include ptosis, ophthalmoparesis, and weakness of the cervical and finger extensor muscles as well as marked phenotypic heterogeneity.

Glioblastoma multiforme at the corpus callosum with spinal leptomeningeal metastasis

Glioblastoma multiforme (GBM) often occurs in the supratentorial white matter including corpus callosum. However, spinal leptomeningeal metastasis in cases of supratentorial GBM has been reported to be rare and there is usually a long interval between the cerebral lesion and the spinal seeding. We report here a case of GBM at the corpus callosum and other parts of the brain with simultaneous manifestation of spinal leptomeningeal seeding. The patient exhibited an abnormal motor behavior of the left hand as mirror movement when the right hand was performing a unimanual task (diagonistic dyspraxia) which is a sign of lesion of the posterior part and splenium of the corpus callosum. There were also signs of peripheral nerve or nerve root involvement suggestive of spinal metastasis without any sensory symptoms. He died 3 months after the onset of the symptoms confirming the poor prognosis and short survival time in cases with spinal leptomeningeal metastasis reported previously. The cerebral GBM with spinal seeding was disclosed at autopsy.

Prenatal ultrasound diagnosis in Thailand

Ultrasound technology has been extensively employed in obstetric and gynecologic practice for several decades. It has been used not only in gestational age estimation, placental location, amniotic fluid assessment but also in antenatal diagnosis of fetal abnormalities of various systems. The incidence of Congenital Heart Disease (CHD) is currently estimated to be 8 to 9 out of every 1,000 live births. Congenital heart disease is thought to be a multifactorial disorder in over 90% of the cases. Pioneer studies on the ultrasound investigation of the heart were reported in the early 1970s. Since the introduction of high resolution real-time ultrasound in the late 1970s, reports on ultrasound assessment of fetal cardiac anatomy and function have been appearing with increasing frequency in both the obstetric and cardiologic literature. At present, fetal echocardiography is a well established technique for the prenatal diagnosis of CHD. However, the distribution of the technique is still limited as it requires both a very experienced operator and meticulous scanning. Screening the entire obstetric population does not appear possible at present. Therefore fetal echocardiography is as necessarily directed toward selected pregnancies carrying a higher-than-normal risk of fetal cardiac anomalies. The progressive developments in cardiac ultrasound during the past two decades have substantially altered the practice of perinatologists, obstetricians and cardiologists. Total cardiac ultrasound studies are now becoming the primary armamentarium in the diagnosis of fetal congenital heart diseases. Since a 92% sensitivity of 4-chamber view in screening fetal heart diseases was first reported in 1987, 4-chamber view has been widely recommended for routine use in fetal sonographic examinations. Recent studies have demonstrated somewhat variable results and have suggested incorporation of the out flow should thoroughly understand the advantages and limitations of fetal cardiac scanning especially the 4-chamber view in order that the appropriate information and management plan can be offered to the patients. Fetal cardiac scanning is well recognized as one of the most tedious scanning of all fetal organ systems. With a tremendous advancement in ultrasound resolution including color imaging capacity several kinds of fetal cardiac anomalies could be diagnosed antenatally which inevitably allows more proper management plan for couples engaged in these.

Prenatal diagnosis of pulmonary atresia by fetal echocardiography

With an improvement in cardiac imaging during the past 20 years, fetal echocardiography has progressively altered the practice of obstetricians and become a principle armamentarium for the diagnosis of fetal heart diseases. We presented a case of pulmonary atresia with intact ventricular septum diagnosed prenatally using fetal echocardiography.

Doppler umbilical artery flow velocity waveforms in pregnancies complicated by major fetal malformations

A pulse-wave Doppler ultrasound was used to identify fetal umbilical cord and to obtain flow-velocity waveforms. The umbilical artery Doppler indices were determined in 34 fetuses with major congenital malformations between 20 and 38 wks' gestation. Reference ranges of fetal umbilical artery systolic and diastolic (S/D) ratio, pulsatility index (PI) and resistance index (RI) with gestation were constructed from a cross-sectional study of 331 appropriate for gestation age fetuses of 16 to 41 wks' gestation. The records were reviewed to determine the changes associated with fetal malformation. Twenty five of 34 patients with major congenital anomalies showed high S/D ratio, PI and RI in waveforms taken from the umbilical artery. All fetuses with chromosomal aneuploidy (10 cases) had high umbilical artery S/D ratio, PI and RI. It appears that a fetal mechanism may determine the changes in the umbilical placental circulation resulting in an umbilical artery pattern of high flow resistance in fetuses with congenital anomalies.

Intrauterine-pressure studies in Thai nulliparous labour: the use of catheter-tip pressure transducer

Uterine activity was studied in 35 nulliparous Thai women who were in the active phase of spontaneous labour, and who were delivered vaginally without supplementary oxytocin or assisted delivery. A catheter-tip pressure transducer coupled with a uterine activity integrator was used to measure and quantitate uterine activity. Progression of normal labour was defined as labour progressing along the Friedman's curve in the active phase. In nulliparous Thai women, the minimum level of uterine activity likely to be associated with labour progress was 322 kPas/15 min at 3 cm cervical dilatation. The mean and median levels in the active phase of normal labour were 1,075.6 and 952.0 kPas/15 min, respectively. There was a weak correlation (R = 0.3) between an increasing cervical dilatation and uterine activity.

Pelvic actinomycosis in pregnancy: a case report and review of the literature

The first reported case in Thailand of pelvic actinomycosis during pregnancy is presented. It occurred in a 38-year-old Thai female with a history of IUD wearing for 2 years until the symptoms of intermittent lower abdominal pain. She had a history of postcoital bleeding at 16 weeks' pregnancy and bleeding per vagina during labor at 40 weeks' pregnancy. Speculum examination showed an irregular, friable, easily bleeding mass (3-4 cm in diameter). The specimens of the mass at the posterior fornix were obtained for culture and pathological examination. Right tubo-ovarian complex measured 10 x 4 x 4 centimeters in diameter, extending through the cul-de-sac to the vaginal canal at the posterior fornix, was identified during exploratory laparotomy. Low transverse cesarean section was performed. The pathological diagnosis was actinomycosis of right fallopian tube and ovary. The patient was treated with tetracycline.

Maternal perception of sound-provoked fetal movement as a test of antepartum fetal wellbeing

Maternal perception of sound-provoked fetal movement test was studied on 506 occasions in 443 women with obstetric or medical antenatal risk factors after 26 weeks gestation. The response was compared with a nonstress test (NST) performed immediately after a three-second vibroacoustic stimulation with an electronic artificial larynx. A positive response to sound stimulation, recorded as a fetal movement by the mother, occurred on 497 occasions (97.3%) and was accompanied by a reactive NST on 484 occasions; giving a specificity of 99.6 per cent and a negative predictive value of 97.4 per cent. An inconclusive or negative response to sound (2.7%) had a sensitivity of 35.0 per cent and a positive predictive value for a nonreactive NST of 77.8 per cent. Results of sound-provoked fetal movement test and NST, performed within a week of delivery, in 434 women were compared with fetal outcome. The maternal perception of sound-provoked fetal movement test had better specificity (99.1% vs 96.9%), positive predictive value (55.6% vs 35.0%) for poor fetal outcome than the NST, although its sensitivity (50.0% vs 70.0%) and negative predictive value (98.8% vs 99.3%) were lower. Maternal perception of sound-provoked fetal movement test may suffice as an inexpensive and simple method of evaluating antepartum fetal well-being in risk situations. When the mother does not feel any sound provoked fetal movement, NST is then performed. This clinical application can be helpful in a primary health care setting where rapid assessment of fetal health at risk is required.

Rapid karyotyping in the second and third trimesters for fetuses at risk of chromosomal abnormalities at Chulalongkorn Hospital

Transabdominal fetal blood sampling under ultrasonic guidance was performed in 20 fetuses at 18 to 34 weeks gestation. Pure fetal blood was obtained in all cases; 11 from the umbilical veins at the placental cord insertion, 7 from the fetal intrahepatic veins and 2 from the fetal hearts. Rapid karyotype was obtained within 7 days by fetal lymphocyte culture. Chromosomal abnormality was detected in 5 (25.0%) fetuses. Abnormal karyotype was found in 4 of 8 fetuses with structural malformations detected by antenatal ultrasound and in 1 of 5 fetuses of elderly mothers at advanced gestational ages. This suggested that in fetuses at risk of chromosomal abnormality, rapid karyotype should be obtained and fetal blood sampling is justified in the second or third trimester.

Intrauterine growth retardation: incidence, screening results, pregnancy outcome

Intrauterine growth retardation is detrimental to the health of fetuses and neonates both immediately and in the long run. A risk scoring system to help screen for this complication has been developed as a result of this prospective study. With the incidence of intrauterine growth retardation at approximately 9 per cent in this study population, the final risk scoring system with its 6 variables and total score of 10 was found to be quite useful as a screening method because of its high sensitivity (91.18%) and high negative predictive value (98.14%). Screening by this risk scoring system should be helpful and prove practical among health personnel with varying levels of expertise and experience. Most gravidae had easy labour and delivered within 24 hours. Instrumental delivery rate was high with caesarean section rate of 17.6 per cent. Almost 70 per cent of the intrauterine growth retarded babies were symmetrical type and the perinatal mortality rate in this group was 42.3 which is approximately 4 times that in general population delivered at this hospital.

Laparoscopic tubal electrocoagulation for sterilization: 5000 cases

Five thousand cases of laparoscopic tubal electrocoagulation were performed for voluntary interval sterilization in outpatient Thai women from January 1974 through June 1978. Immediate complications occurring during surgery resulted from mesosalpingeal hemorrhage, which was successfully managed by omental packing with or without repeated electrocoagulation. The overall failure rate was 0.40%. The authors find this method of tubal electrocoagulation for fertility management to be reliable and safe as an outpatient procedure and to provide rapid convalescence.