Usefulness of Cardiac MIBG Scintigraphy, Olfactory Testing and Substantia Nigra Hyperechogenicity as Additional Diagnostic Markers for Distinguishing between Parkinson's Disease and Atypical Parkinsonian Syndromes

Impact of autonomic symptoms on the clinical course of Parkinson's disease

PURPOSE

Patients with Parkinson's disease (PD) exhibit various degrees of autonomic symptoms, which may be associated with Lewy body pathology distributed extensively in the autonomic nervous system. We hypothesized that the severity of autonomic symptoms reflects the severity of PD-related pathology, resulting in poor outcomes. The purpose of this study was to evaluate the impact of autonomic symptoms on PD progression.

METHODS

We conducted a follow-up study among consecutive patients with PD at Dokkyo Medical University Hospital. Patients underwent comprehensive baseline evaluations and were classified into high and low autonomic symptom groups using the Scale for Outcomes in Parkinson's Disease-Autonomic (SCOPA-AUT). The Kaplan‒Meier survival curves were used to analyze the time to discontinuation of their visits because of PD-related endpoints and to evaluate the association with high SCOPA-AUT scores.

RESULTS

Of the 101 patients, 74 (73%) met the inclusion criteria. During the follow-up period (mean 1654 days), 22/74 patients reached PD-related endpoints (death, 4; hospitalization, 9; nursing home institutionalization, 9). PD patients with high SCOPA-AUT scores reached the endpoints faster than those with low SCOPA-AUT scores. A high SCOPA-AUT score, including gastrointestinal, urinary, and thermoregulation domains; high motor symptom scores; and low specific binding ratios (SBRs) on 123I FP-CIT-SPECT (DAT-SPECT) were associated with reaching PD-related endpoints. A high SCOPA-AUT score was associated with reaching the endpoints even after adjustment for covariates.

CONCLUSIONS

Patients with high autonomic symptom scores had a greater risk of reaching PD-related endpoints than patients with low autonomic symptom scores.

Differentiating progressive supranuclear palsy from other movement disorders using transcranial sonography: a systematic review and meta-analysis

Progressive supranuclear palsy (PSP) is an atypical parkinsonism that presents with different phenotypes. There are still no validated diagnostic biomarkers for early diagnosis of PSP. Transcranial sonography (TCS) is a promising tool in the differential diagnosis of parkinsonian disorders; however, there are no systematic investigations about the application of TCS in PSP patients. Therefore, we performed a systematic review and meta-analysis to discuss the role of TCS in diagnosing PSP by systematically searching PubMed, Cochrane Library, Chinese National Knowledge Infrastructure and Wan Fang databases. Of 66 obtained records, 16 articles, including 366 patients with PSP, were included. Our results showed the estimated random-effects pooled prevalence of substantia nigra hyperechogenicity in patients with PSP was 22% (95% CI 12-32%), lenticular nucleus hyperechogenicity was 70% (95% CI 52-82%), and enlarged third ventricle was 71% (95% CI 55-85%). Additionally, a normal echogenicity substantia nigra in TCS showed 70% sensitivity (95% CI 56-81%) and 86% specificity (95% CI 75-86%) to differentiate PSP from Parkinson's disease. In conclusion, TCS is an important supplementary biomarker for diagnosing PSP. At the same time, the diagnostic value of TCS in discriminating PSP from other atypical parkinsonism and between different PSP phenotypes needs further exploration.

Impact of diabetes and glycated hemoglobin level on the clinical manifestations of Parkinson's disease

BACKGROUND

The coexistence of diabetes mellitus (DM) has been suggested to accelerate the progression of Parkinson's disease (PD) and make the phenotype more severe. In this study, we investigated whether DM or glycated hemoglobin (HbA1c) levels affect the differences in motor and nonmotor symptoms.

METHODS

We conducted a cross-sectional study including 140 consecutive Japanese patients with PD for whom medical history and serum HbA1c records were available. The PD patients with a DM diagnosis were classified into the diabetes-complicated group (PD-DM) and the nondiabetes-complicated group (PD-no DM). Next, patients were classified based on a median HbA1c value of 5.7, and clinical parameters were compared. The correlations between HbA1c levels and other clinical variables were analyzed.

RESULTS

Of 140 patients, 23 patients (16%) had DM. Compared to PD-no DM patients, PD-DM patients showed lower MMSE scores. Compared to the lower HbA1c group, the higher HbA1c group showed a higher MDS-UPDRS part III score and a lower metaiodobenzylguanidine (MIBG) scintigraphy heart-to-mediastinum (H/M) ratio. HbA1c levels were positively correlated with age and the MDS-UPDRS part III score and negatively correlated with the MMSE score and H/M ratio on cardiac MIBG scintigraphy. Binary logistic regression analysis, which included age, sex, disease duration, and MMSE and MDS-UPDRS part III scores as independent variables, revealed that a lower MMSE score was an independent contributor to PD-DM and PD with high HbA1c levels.

CONCLUSIONS

DM complications and high HbA1c levels may affect cognitive function in patients with PD.

Cardiac 123I-Metaiodobenzylguanidine (MIBG) Scintigraphy in Parkinson's Disease: A Comprehensive Review

Cardiac sympathetic denervation, as documented on 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, is relatively sensitive and specific for distinguishing Parkinson's disease (PD) from other neurodegenerative causes of parkinsonism. The present study aims to comprehensively review the literature regarding the use of cardiac MIBG in PD. MIBG is an analog to norepinephrine. They share the same uptake, storage, and release mechanisms. An abnormal result in the cardiac MIBG uptake in individuals with parkinsonism can be an additional criterion for diagnosing PD. However, a normal result of cardiac MIBG in individuals with suspicious parkinsonian syndrome does not exclude the diagnosis of PD. The findings of cardiac MIBG studies contributed to elucidating the pathophysiology of PD. We investigated the sensitivity and specificity of cardiac MIBG scintigraphy in PD. A total of 54 studies with 3114 individuals diagnosed with PD were included. The data were described as means with a Hoehn and Yahr stage of 2.5 and early and delayed registration H/M ratios of 1.70 and 1.51, respectively. The mean cutoff for the early and delayed phases were 1.89 and 1.86. The sensitivity for the early and delayed phases was 0.81 and 0.83, respectively. The specificity for the early and delayed phases were 0.86 and 0.80, respectively.

Factors contributing to sleep disturbances and excessive daytime sleepiness in patients with Parkinson's disease

Background

Sleep disturbances and excessive daytime sleepiness (EDS) are common non-motor symptoms in patients with Parkinson's disease (PD). The purpose of this study was to identify the contributors to sleep disturbances, including insomnia, restless legs syndrome, rapid eye movement sleep behavior disorder (RBD), sleep-disordered breathing, nocturnal akinesia and EDS, in patients with PD.

Methods

We conducted a cross-sectional study including 128 consecutive Japanese patients with PD. Sleep disturbances and EDS were defined as a PD Sleep Scale-2 (PDSS-2) total score ≥15 and an Epworth Sleepiness Scale (ESS) score >10, respectively. The patients were divided into four groups according to the presence or absence of sleep disturbances and EDS. We evaluated the disease severity, motor symptoms, cognition, olfactory test, the Scales for Outcomes in PD-Autonomic dysfunction (SCOPA-AUT), the Beck Depression Inventory-II (BDI-II), and the RBD Screening Questionnaire Japanese version (RBDSQ-J).

Results

Of 128 patients, 64 had neither EDS nor sleep disturbances, 29 had sleep disturbances without EDS, 14 had EDS without sleep disturbances, and 21 had both EDS and sleep disturbances. Patients with sleep disturbances had higher BDI-II scores than those without sleep disturbances. Probable RBD was more frequent in patients with both sleep disturbances and EDS than in those with neither EDS nor sleep disturbances. The SCOPA-AUT score was lower in patients with neither EDS nor sleep disturbances than in patients in the other three groups. Using multivariable logistic regression analysis with neither sleep disturbances nor EDS as a reference group, that the SCOPA-AUT score was an independent contributor to sleep disturbances (adjusted OR, 1.192; 95% CI, 1.065-1.333; P = 0.002) or EDS (OR, 1.245; 95% CI, 1.087-1.424; P = 0.001) and that the BDI-II (OR, 1.121; 95% CI, 1.021-1.230; P = 0.016) and RBDSQ-J scores (OR, 1.235; 95% CI, 1.007-1.516; P = 0.043) as well as the SCOPA-AUT score (OR, 1.137; 95% CI, 1.006-1.285; P = 0.040) were independent contributors to both sleep disturbances and EDS.

Conclusions

Autonomic symptoms were associated with patients with sleep disturbances or EDS, and depressive and RBD symptoms in addition to autonomic symptoms were associated with patients with both sleep disturbances and EDS.

Multiple system atrophy

Multiple system atrophy (MSA) is a rare neurodegenerative disease that is characterized by neuronal loss and gliosis in multiple areas of the central nervous system including striatonigral, olivopontocerebellar and central autonomic structures. Oligodendroglial cytoplasmic inclusions containing misfolded and aggregated α-synuclein are the histopathological hallmark of MSA. A firm clinical diagnosis requires the presence of autonomic dysfunction in combination with parkinsonism that responds poorly to levodopa and/or cerebellar ataxia. Clinical diagnostic accuracy is suboptimal in early disease because of phenotypic overlaps with Parkinson disease or other types of degenerative parkinsonism as well as with other cerebellar disorders. The symptomatic management of MSA requires a complex multimodal approach to compensate for autonomic failure, alleviate parkinsonism and cerebellar ataxia and associated disabilities. None of the available treatments significantly slows the aggressive course of MSA. Despite several failed trials in the past, a robust pipeline of putative disease-modifying agents, along with progress towards early diagnosis and the development of sensitive diagnostic and progression biomarkers for MSA, offer new hope for patients.

An Update on Gene Therapy Approaches for Parkinson's Disease: Restoration of Dopaminergic Function

At present there is a significant unmet need for clinically available treatments for Parkinson’s disease (PD) patients to stably restore balance to dopamine network function, leaving patients with inadequate management of symptoms as the disease progresses. Gene therapy is an attractive approach to impart a durable effect on neuronal function through introduction of genetic material to reestablish dopamine levels and/or functionally recover dopaminergic signaling by improving neuronal health. Ongoing clinical gene therapy trials in PD are focused on enzymatic enhancement of dopamine production and/or the restoration of the nigrostriatal pathway to improve dopaminergic network function. In this review, we discuss data from current gene therapy trials for PD and recent advances in study design and surgical approaches.

Electrogastrography for diagnosis of early-stage Parkinson's disease

INTRODUCTION

Patients with Parkinson's disease (PD) often present with gastric symptoms. Electrogastrography (EGG) can noninvasively assess gastric electric activity and may be useful for early PD diagnosis. The present study aimed to compare the efficacy of EGG in early PD diagnosis with those of ¹²³I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy and odor stick identification test -Japanese version (OSIT-J).

METHODS

Thirty-seven untreated PD patients (mean age ± SD, 66 ± 8years; disease duration < 3 years) and 20 healthy control subjects (68 ± 6.9 years) were recruited. EGG and OSIT-J were performed in both groups, and MIBG scintigraphy in the PD group. EGG parameters were assessed in the preprandial and early and late postprandial segments using power spectrum analysis.

RESULTS

Irregular EGG waves were observed in PD patients. The preprandial instability coefficient of dominant frequency (ICDF), an index of EGG irregularity, in PD patients (9.5% [6.3%]) was higher than that in controls (3.9% [3.9%], p = 0.00005). The OSIT-J score was also lower in PD patients (4.6 [3.3]) than in controls (7.7 [3.3], p = 0.006). In receiver operating characteristics analyses, the areas under the curves of preprandial ICDF and OSIT-J were 0.83 and 0.72, respectively. The sensitivities of preprandial ICDF and MIBG (delayed-phase) scintigraphy were 73% and 70%, respectively.

CONCLUSIONS

Early and untreated PD patients showed irregular EGG waves and high ICDF. EGG showed better accuracy than the olfactory test for early PD diagnosis and similar sensitivity to MIBG scintigraphy.

Laboratory-Supported Multiple System Atrophy beyond Autonomic Function Testing and Imaging: A Systematic Review by the MoDiMSA Study Group

Background

Neuroimaging has been used to support a diagnosis of possible multiple system atrophy (MSA). Only blood pressure changes upon standing are included in the second consensus criteria but other autonomic function tests (AFT) are also useful to diagnose widespread and progressive autonomic failure typical of MSA. Additional diagnostic tools are of interest to improve accuracy of MSA diagnosis.

Objectives

To assess the utility of diagnostic tools beyond brain imaging and AFT in enhancing a laboratory-supported diagnosis of MSA to support the upcoming revision of the consensus criteria.

Methods

The International Parkinson and Movement Disorders Society MSA Study Group (MoDiMSA) performed a systematic review of original papers on biomarkers, sleep studies, genetic, neuroendocrine, neurophysiological, neuropsychological and other tests including olfactory testing and acute levodopa challenge test published before August 2019.

Results

Evaluation of history of levodopa responsiveness and olfaction is useful in patients in whom MSA-parkinsonian subtype is suspected. Neuropsychological testing is useful to exclude dementia at time of diagnosis. Applicability of sphincter EMG is limited. When MSA-cerebellar subtype is suspected, a screening for the common causes of adult-onset progressive ataxia is useful, including spinocerebellar ataxias in selected patients. Diagnosing stridor and REM sleep behavior disorder is useful in both MSA subtypes. However, none of these tools are validated in large longitudinal cohorts of postmortem confirmed MSA cases.

Conclusions

Despite limited evidence, additional laboratory work-up of patients with possible MSA beyond imaging and AFT should be considered to optimize the clinical diagnostic accuracy.

Can Autonomic Testing and Imaging Contribute to the Early Diagnosis of Multiple System Atrophy? A Systematic Review and Recommendations by the Movement Disorder Society Multiple System Atrophy Study Group

Background

In the current consensus diagnostic criteria, the diagnosis of probable multiple system atrophy (MSA) is based solely on clinical findings, whereas neuroimaging findings are listed as aid for the diagnosis of possible MSA. There are overlapping phenotypes between MSA-parkinsonian type and Parkinson's disease, progressive supranuclear palsy, and dementia with Lewy bodies, and between MSA-cerebellar type and sporadic adult-onset ataxia resulting in a significant diagnostic delay and misdiagnosis of MSA during life.

Objectives

In light of an ongoing effort to revise the current consensus criteria for MSA, the Movement Disorders Society Multiple System Atrophy Study Group performed a systematic review of original articles published before August 2019.

Methods

We included articles that studied at least 10 patients with MSA as well as participants with another disorder or control group for comparison purposes. MSA was defined by neuropathological confirmation, or as clinically probable, or clinically probable plus possible according to consensus diagnostic criteria.

Results

We discuss the pitfalls and benefits of each diagnostic test and provide specific recommendations on how to evaluate patients in whom MSA is suspected.

Conclusions

This systematic review of relevant studies indicates that imaging and autonomic function tests significantly contribute to increasing the accuracy of a diagnosis of MSA.

Combination of midbrain-to-pontine ratio and cardiac MIBG scintigraphy to differentiate Parkinson's disease from multiple system atrophy and progressive supranuclear palsy

Background

An early clinical differentiation between Parkinson's disease (PD) and multiple system atrophy (MSA) or progressive supranuclear palsy (PSP) remains a challenge. The purpose of this study was to evaluate the usefulness of the combination use of midbrain-to-pontine ratio (M/P ratio) from magnetic resonance imaging (MRI) with cardiac ¹²³I-metaiodobenzylguanidine (MIBG) uptake for differentiating PD from MSA and PSP.

Methods

Ninety-six parkinsonian patients (70 PD, aged 68.5 ± 9.5 years; 16 MSA, aged 67.9 ± 7.5 years; 10 PSP, aged 70.4 ± 9.4 years) who underwent MRI and cardiac MIBG scintigraphy were included in this study. Receiver operating characteristic (ROC) curve analysis was used to assess the sensitivity and specificity for distinguishing PD from MSA and PSP patients. The diagnostic accuracy of these tests was also assessed among patients at the early disease stage (defined as patients with a disease duration of 3 years or less).

Results

The individual diagnostic sensitivity of the M/P ratio and cardiac MIBG scintigraphy was 87.1% and 67.1% in PD vs. MSA and 78.6% and 67.1% in PD vs. PSP, respectively. The diagnostic specificity of the M/P ratio and cardiac MIBG scintigraphy was 56.3% and 100% in PD vs. MSA and 70.0% and 90% in PD vs. PSP, respectively. With the optimal cutoff values, at least one positive result (either the M/P ratio or cardiac MIBG revealed abnormalities) improved sensitivity (95.7%) without decrease of specificity (56.3%) in PD vs. MSA, as well as in PD vs. PSP (100% sensitivity, 70.0% specificity). In contrast, both positive results of two tests had good specificity but low sensitivity in PD vs. MSA (60.0% sensitivity and 100% specificity) and in PD vs. PSP (47.1% sensitivity and 90% specificity). Similar trends were observed in early-stage patients.

Conclusion

Although M/P ratio alone was potentially useful for distinguishing PD from MSA or PSP, the combined use with cardiac MIBG scintigraphy can further improve the diagnostic accuracy of PD from MSA or PSP.

Leg restlessness preceding the onset of motor symptoms of Parkinson disease: A case series of 5 patients

Patients with Parkinson disease (PD) often show restless legs syndrome (RLS), leg motor restlessness (LMR) and other leg restlessness (OLR) related to sensorimotor symptoms.Here, we describe 5 patients who presented with leg restlessness as an early manifestation of PD.In case 1, the patient had leg restlessness that was not LMR or RLS and preceded the onset of motor symptoms by 1 year. In case 2, LMR preceded motor symptoms by 2 years. Case 3 had unilateral RLS symptoms on the left side of the body for 33 years. Two and a half years after the spread of RLS symptoms to the right leg with increased frequency of left-sided RLS symptoms, the patient developed PD at the age of 58 years. In cases 4 and 5, RLS symptoms preceded motor symptoms by 3 months and 1 month, respectively. All patients developed Parkinsonism within 3 years (median, 1.0 year; range 0.083-2.5 years) after initial onset or exacerbation of leg restlessness. All patients had frequent leg restlessness symptoms (6-7 days per week). In our series, the preceding leg restlessness was unilateral and confined to the dominant side of the subsequent Parkinsonism, or preceding leg restlessness was bilateral but dominant on the dominant side of the subsequent Parkinsonism.Clinicians should be aware that late-onset leg restlessness (>50 years of age) including RLS, LMR, and OLR, particularly if frequent and asymmetrical, can be an early nonmotor manifestation of PD.

Clinical characteristics and quality of life in Chinese patients with multiple system atrophy

OBJECTIVES

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder that causes early sustained disability and poor health-related quality of life (HrQoL). The clinical features and their effects on the HrQoL of patients in China have received little attention in the research literature. We evaluated the clinical characteristics and HrQoL of Chinese patients with MSA.

MATERIALS AND METHODS

A total of 143 patients with MSA from the Department of Neurology, Shanghai Ruijin Hospital, were enrolled in the study from March 2014 to May 2017. Basic demographic data, motor symptoms, non-motor symptoms, and HrQoL were assessed and compared with data from 198 patients with idiopathic Parkinson's disease (PD) who were matched by age, gender, and disease duration. Factors influencing the HrQoL of MSA patients were also analyzed.

RESULTS

The ratio of patients with predominant parkinsonism (MSA-P) and prominent cerebellar ataxia (MSA-C) was 95:48 among the 143 MSA patients. MSA-P patients had a longer disease duration (p = 0.002), higher levodopa equivalent daily dose (p < 0.001), higher scores on the Unified Multiple System Atrophy Rating Scale (UMSARS) I (p = 0.026), UMSARS II (p < 0.001), UMSARS IV (p = 0.019), the Hamilton Rating Scale for Depression (p = 0.001), the Hamilton Anxiety Scale (p = 0.013), and lower scores on measures of olfaction (p = 0.021) and cognitive function (p = 0.044) than the MSA-C patients. Stepwise regression analysis showed that depression, anxiety, degree of disability, and disease severity were independent predictors of decreased HrQoL.

CONCLUSIONS

The results indicate that MSA-P patients have more severe motor impairment, hyposmia, depression, anxiety, cognitive impairment, and lower HrQoL than MSA-C patients. Depression, anxiety, degree of disability, and disease severity are predictors of poor HrQoL among Chinese patients with MSA.

Transcranial B-Mode Sonography in Movement Disorders

Applying a 2-4MHz probe at the temporal bone window transcranial B-mode sonography (TCS) enables the depiction of the brain parenchyma through the intact skull. Meanwhile it has been applied for the diagnosis and the differential diagnosis of movement disorders for decades. In the first part of this chapter, we summarize the technical requirements and describe the ultrasound method for optimal TCS examination. Imaging planes and the relevant structures are explained in detail. In the second part of the chapter, we focus on the role of substantia nigra hyperechogenicity for the diagnosis of Parkinson's disease (PD) and prodromal PD. In this part, we also mention the role of TCS in atypical and secondary Parkinsonian syndromes and other movement disorders. Summarizing all these information we explain how TCS can be helpful for the differential diagnosis of movement disorders. The current data show that TCS is an easily applicable and economic imaging method which can be used as an additional tool for the diagnosis of PD with a high sensitivity (>85%), specificity (>80%) and inter-rater reliability (>84%) as well as for the differential diagnosis of movement disorders. Lately, TCS has also been utilized in further areas such as the detection of individuals at risk for PD or the determination of electrode localization in patients with deep brain stimulation. An insufficient temporal bone window especially in the elderly and the necessity of an experienced investigator are limitations of this method.

Does normal substantia nigra echogenicity make a difference in Parkinson's disease diagnosis? A real clinical practice follow-up study

OBJECTIVES

Substantia nigra hyperechogenicity (SN+) detected by transcranial ultrasound (TUS) is useful for Parkinson's disease (PD) diagnosis. Approximately 15% false negative results of unknown significance are reported. However, most TUS studies are transversal, and diagnosis of PD may change during follow-up.

METHODS

Analysis of our prospective registry of TUS in clinical practice, selecting patients with sufficient bone window, to whom TUS was performed because of suspected PD, and a minimum of 3-year follow-up. Subjects were classified regarding SN echogenicity (SN+/SN-).

RESULTS

172 patients (122 SN+, 50 SN-), mean age 71 years (25-90), were included. At the end of follow-up, PD diagnosis was retained by 91% SN+ vs. 54% SN- subjects (p < 0.0001), while final diagnosis of atypical parkinsonism (3%SN+ vs. 16%SN-, p:0.0059) was more frequent in SN-. Dopaminergic therapy response was associated with SN+ (88% SN+ vs. 50% SN-, p < 0.0001), as were abnormal DaTSCANs (90%SN+ vs. 56%SN-, p 0.0027). SN echogenicity had 80% sensitivity and 68% specificity for PD diagnosis, while SPECT had 91% and 73%, respectively. SN+ was the only baseline predictor of keeping PD diagnosis at the end of follow-up, with an odds ratio of 12 (95% CI 3-42) (p < 0.001).

CONCLUSIONS

In our sample of patients with suspected PD, SN hyperechogenicity predicted PD diagnosis in the long term with a high odds ratio. Conversely, a baseline normal SN echogenicity was associated with a poorer response to PD therapy and change to a different diagnosis from PD. Normal SN appears to be a caveat for clinicians to check for atypical parkinsonism features during follow-up.

The role of substantia nigra sonography in the differentiation of Parkinson's disease and multiple system atrophy

Background

The differential diagnosis of Parkinson's disease (PD) and multiple system atrophy (MSA) remains a challenge, especially in the early stage. Here, we assessed the value of transcranial sonography (TCS) to discriminate non-tremor dominant (non-TD) PD from MSA with predominant parkinsonism (MSA-P).

Methods

Eighty-six MSA-P patients and 147 age and gender-matched non-TD PD patients who had appropriate temporal acoustic bone windows were included in this study. All the patients were followed up for at least 2 years to confirm the initial diagnosis. Patients with at least one substantia nigra (SN) echogenic size ≥18 mm² were classified as hyperechogenic, those with at least one SN echogenic size ≥25 mm² was defined as markedly hyperechogenic.

Results

The frequency of SN hyperechogenicity in non-TD PD patients was significantly higher than that in MSA-P patients (74.1% vs. 38.4%, p <  0.001). SN hyperechogenicity discriminated non-TD PD from MSA-P with sensitivity of 74.1%, specificity of 61.6%, and positive predictive value of 76.8%. If marked SN hyperechogenicity was used as the cutoff value (≥ 25 mm²), the sensitivity decreased to 46.3%, but the specificity and positive predictive value increased to 80.2 and 80.0%. Additionally, in those patients with SN hyperechogenicity, positive correlation between SN hyperechogenicity area and disease duration was found in non-TD PD rather than in MSA-P patients. In this context, among early-stage patients with disease duration ≤3 years, the sensitivity, specificity and positive predictive value of SN hyperechogenicity further declined to 69.8%, 52.2%, and 66.7%, respectively.

Conclusions

TCS could help discriminate non-TD PD from MSA-P in a certain extent, but the limitation was also obvious with relatively low specificity, especially in the early stage.

Possible multiple system atrophy with predominant parkinsonism in a patient with chronic schizophrenia: a case report

BACKGROUND

Multiple system atrophy (MSA) is an adult-onset, rare, and progressive neurodegenerative disorder characterized by a varying combination of autonomic failure, cerebellar ataxia, and parkinsonism. MSA is categorized as MSA-P with predominant parkinsonism, and as MSA-C with predominant cerebellar features. The prevalence of MSA has been reported to be between 1.86 and 4.9 cases per 100,000 individuals. In contrast, approximately 1% of the population is affected by schizophrenia during their lifetime; therefore, MSA-P comorbidity is very rare in schizophrenic patients. However, when the exacerbation or progression of parkinsonism occurs in patients with schizophrenia treated with antipsychotics, it is necessary to consider rare neurodegenerative disorders, including MSA-P, in the differential diagnosis of parkinsonism.

CASE PRESENTATION

A 60-year-old female patient with chronic schizophrenia developed possible MSA-P. She had been treated mainly with typical antipsychotics, and presented with urinary incontinence, nocturnal polyuria, and dysarthria around 2011. In 2014, she developed worsening parkinsonian symptoms and autonomic dysfunction. Although her antipsychotic medication was switched to an atypical antipsychotic and the dose reduced, her parkinsonism was not improved. In 2015, modified electroconvulsive therapy produced slight improvements in the symptoms; however, she shortly returned to her symptomatic state. A combination of cardiac ¹²³I-meta-iodobenzylguanidine scintigraphy and ¹²³I-FP-CIT single-photon emission computed tomography imaging, in addition to brain magnetic resonance imaging findings, helped to discriminate MSA-P from other sources of parkinsonism. L-dopa had been prescribed, but she responded poorly and died in the spring of 2016.

CONCLUSIONS

This case report highlights the importance of considering MSA-P in the differential diagnosis for parkinsonism in a patient being treated with antipsychotics for chronic schizophrenia. MSA-P should be considered in patients presenting with worsening and progressing parkinsonism, especially when accompanied by autonomic dysfunction or cerebellar ataxia. Although a definite diagnosis of MSA-P requires autopsy confirmation, a combination of brain magnetic resonance imaging and nuclear medicine scans may help to differentiate suspected MSA-P from the other parkinsonian syndromes. This case also demonstrates that MSA with parkinsonism that is poorly responsive to L-dopa may improve shortly after modified electroconvulsive therapy without worsening psychiatric symptoms.

Reduced gray matter volume is correlated with frontal cognitive and behavioral impairments in Parkinson's disease

OBJECTIVE

To identify the brain-volume reductions associated with frontal cognitive and behavioral impairments in Parkinson's disease (PD).

METHODS

Forty PD patients without dementia or amnesia (Hoehn and Yahr stage 3) and 10 age-matched controls underwent brain magnetic resonance imaging. Cognitive and behavioral impairments were assessed by using the Frontal Assessment Battery (FAB) and Frontal Systems Behavioral Scale (FrSBe), respectively. We applied voxel-based morphometry to investigate the correlations of regional gray matter volume with FAB, FrSBe, and physical disability.

RESULTS

FAB was significantly lower in PD than in controls. FrSBe was significantly higher after PD onset than before, notably in the apathy subscale. FAB and FrSBe were significantly intercorrelated. In PD patients, left inferior frontal volume was positively correlated with FAB, whereas right precentral volume was negatively correlated with FrSBe total score. The brain volumes in both of these regions were not correlated with the Unified PD Rating Scale III.

CONCLUSION

Behavioral impairments in PD tended to coexist with progression of frontal cognitive impairment. Regional atrophy within the frontal lobe was associated with both frontal cognitive and behavioral impairments. However, the specific region responsible for behavioral impairment differed from that for frontal cognitive impairment. These associations were independent of physical disability.

Diagnosis of multiple system atrophy

Multiple system atrophy (MSA) may be difficult to distinguish clinically from other disorders, particularly in the early stages of the disease. An autonomic-only presentation can be indistinguishable from pure autonomic failure. Patients presenting with parkinsonism may be misdiagnosed as having Parkinson disease. Patients presenting with the cerebellar phenotype of MSA can mimic other adult-onset ataxias due to alcohol, chemotherapeutic agents, lead, lithium, and toluene, or vitamin E deficiency, as well as paraneoplastic, autoimmune, or genetic ataxias. A careful medical history and meticulous neurological examination remain the cornerstone for the accurate diagnosis of MSA. Ancillary investigations are helpful to support the diagnosis, rule out potential mimics, and define therapeutic strategies. This review summarizes diagnostic investigations useful in the differential diagnosis of patients with suspected MSA. Currently used techniques include structural and functional brain imaging, cardiac sympathetic imaging, cardiovascular autonomic testing, olfactory testing, sleep study, urological evaluation, and dysphagia and cognitive assessments. Despite advances in the diagnostic tools for MSA in recent years and the availability of consensus criteria for clinical diagnosis, the diagnostic accuracy of MSA remains sub-optimal. As other diagnostic tools emerge, including skin biopsy, retinal biomarkers, blood and cerebrospinal fluid biomarkers, and advanced genetic testing, a more accurate and earlier recognition of MSA should be possible, even in the prodromal stages. This has important implications as misdiagnosis can result in inappropriate treatment, patient and family distress, and erroneous eligibility for clinical trials of disease-modifying drugs.

Nonmotor Aspects of Parkinson's Disease-How Do They Help Diagnosis?

Not only are nonmotor aspects of Parkinson's disease important because of their impact, they also can help diagnose Parkinson's. This chapter summarizes the ways in which recognition of the nonmotor profile of Parkinson's can help in clinical diagnosis. It also emphasizes the essential role that nonmotor Parkinson's disease plays in the diagnosis of prodromal stages of disease.