Parkinsonism with basal ganglia lesions in a patient with uremia: Evidence of vasogenic edema

Mid- and Late-Life Chronic Kidney Disease Is Associated with Parkinson's Disease, Not with an Increased Risk of Alzheimer's Disease

Chronic kidney disease (CKD) is strongly associated with dementia. However, its independent association with Alzheimer's or Parkinson's disease remains unclear. This study investigated the prospective association of patients with CKD aged ≥55 years with an increased risk of Alzheimer's or Parkinson's disease. We conducted a retrospective cohort analysis using a national cohort sample of approximately one million patients. Primary outcome indicators measured included incidence of all-cause dementia, Alzheimer's disease, and Parkinson's disease events using person-years at risk. The hazard ratio was adjusted using the Cox proportional hazards model. We included 952 patients without CKD and 476 with CKD over 55 years using propensity score matching. The CKD group exhibited higher incidences of all-cause dementia, Parkinson's disease, and Alzheimer's disease than the non-CKD group. Furthermore, the CKD group had an elevated risk of all-cause dementia and a significantly increased risk of Parkinson's disease, especially among older women. Notably, the risk of Parkinson's disease was higher within the first 3 years of CKD diagnosis. These findings emphasize the link between CKD in mid- and late-life individuals and a higher incidence of all-cause dementia and Parkinson's disease rather than Alzheimer's disease.

Exploring the Link between Chronic Kidney Disease and Parkinson's Disease: Insights from a Longitudinal Study Using a National Health Screening Cohort

Chronic kidney disease (CKD) and Parkinson's disease (PD) are common illnesses found in the geriatric population. A potential link between CKD and PD emergence has been hypothesized; however, existing conclusions are disputed. In this longitudinal research, we analyzed data acquired from the Korean National Health Insurance Service-Health Screening Cohort. The dataset comprised the health information of 16,559 individuals clinically diagnosed with CKD and 66,236 control subjects of comparable ages, all aged ≥40 years. These subjects participated in health examinations from 2002 to 2019. To assess the correlation between CKD and PD, we employed overlap-weighted Cox proportional hazard regression models. The unadjusted, crude hazard ratio for PD was greater in the CKD group than in the control group (crude hazard ration (HR) 1.20; 95% confidence interval (CI) = 1.04-1.39; p = 0.011). However, the Cox proportional hazard regression analysis, incorporating propensity score overlap weighting, revealed no significant discrepancy after considering confounding variables such as demographic factors, socio-economic status, lifestyle, and concurrent health conditions (adjusted HR (aHR), 1.09; 95% CI = 0.97-1.22; p = 0.147). Subgroup analyses showed a higher probability of PD development among certain CKD individuals, including those who resided in rural areas (aHR, 1.19; 95% CI = 1.03-1.37; p = 0.022), maintained a normal weight (aHR, 1.29; 95% CI = 1.08-1.56; p = 0.006), or had fasting blood glucose levels ≥100 mg/dL (aHR, 1.18; 95% CI = 1.00-1.39; p = 0.046). Therefore, these clinical or environmental factors may influence the incidence of PD in CKD patients. In conclusion, our results suggest that the general CKD population may not exhibit a greater propensity for PD than their non-CKD counterparts. However, this might be contingent upon specific lifestyle and comorbid conditions. Thus, certain lifestyle alterations could be crucial in mitigating the potential manifestation of PD in patients diagnosed with CKD.

Orofacial Dyskinesia in Uremia in Polycystic Kidney Disease

Uremic encephalopathy presenting as involuntary movements of the orofacial region is important to recognize because of reversibility seen with resolution of azotaemia though residual neurological dysfunction might persist. Neuroimaging is important part of diagnosis with typical lesions involving basal ganglia seen mostly in diabetic patients. Our case highlights a patient with non-diabetic uremic encephalopathy with facial dyskinesia which is rare with a lesion in unilateral lentiform nucleus and small white matter hyperintensities. Resolution following dialysis pointed to uraemia as aetiology.

Movement Disorders Resulting From Bilateral Basal Ganglia Lesions in End-Stage Kidney Disease: A Systematic Review

Objective

The basal ganglia (BG) are susceptible to fluctuations in blood urea levels, sometimes resulting in movement disorders. We described patients with end-stage kidney disease (ESKD) presenting with movement disorders associated with bilateral BG lesions on imaging.

Methods

We report four patients and systematically reviewed all published cases of ESKD presenting with movement disorders and bilateral BG lesions (EBSCOhost and Ovid).

Results

Of the 72 patients identified, 55 (76.4%) were on regular dialysis. Parkinsonism was the most common movement disorder (n = 39; 54.2%), followed by chorea (n = 24; 33.3%). Diabetes mellitus (n = 51; 70.8%) and hypertension (n = 16; 22.2%) were the most common risk factors. Forty-three (59.7%) were of Asian ethnicity. Complete clinical resolution was reported in 17 (30.9%) patients, while 38 (69.1%) had incomplete clinical resolution with relapse. Complete radiological resolution occurred in 14 (34.1%) patients.

Conclusion

Movement disorders associated with BG lesions should be recognized as a rare and potentially reversible metabolic movement disorder in patients with ESKD.

Transcranial sonography depicts a larger substantia nigra echogenic area in renal transplant patients on calcineurin inhibitors than on rapamycin

BACKGROUND

After kidney transplantation neurologic manifestations may develop, including Parkinson's disease (PD). An enlarged substantia nigra (SN) by transcranial sonography has been recognized as a marker of PD.

METHODS

In renal transplant recipients (RTRs = 95) and controls (n = 20), measurement of mesencephalon, SN, third ventricle, spleen and carotid intima-media thickness (cIMT) and middle cerebral artery (MCA), kidney and spleen arteries Doppler resistive index (RI) were performed.

RESULTS

RTRs had larger SN, third ventricle and cIMT and higher renal RI than controls. The SN was larger in the CNIs group than in controls and rapamycin group, while the third ventricle was similar between patients but larger than in controls. In RTRs, SN showed a direct linear correlation with spleen and the third ventricle with age, cIMT and RI of the MCA, kidney and spleen. In CNIs group the SN correlated positively with age and cIMT, while the third ventricle reproduced RTRs correlations. Rapamycin group showed a direct linear relationship between the third ventricle and age and RI of the MCA, kidney and spleen; SN showed no correlations.

CONCLUSION

RTRs on CNIs present a larger SN area than on rapamycin, probably due to the antiproliferative effect of rapamycin. This finding might be relevant when interpreting TCS in RTRs.

Focal brain lactate accumulation in metformin-induced encephalopathy without systemic lactic acidosis: A case report suggesting mitochondrial vulnerability in lentiform fork sign

Metformin causes metabolic encephalopathy in some patients with end-stage chronic kidney disease, resulting in impaired consciousness and parkinsonism. This encephalopathy has a very characteristic magnetic resonance imaging feature in lentiform nuclei known as the “lentiform fork sign”. However, the mechanism is unknown. Here, we report a case of metformin-induced encephalopathy with a novel observation of lactate accumulation in the lentiform nuclei on magnetic resonance spectroscopy without systemic lactic acidosis. Since metformin is an inhibitor of mitochondrial complex-I, this focal brain lactate accumulation implies that a part of the pathogenesis of metformin-induced encephalopathy is the focal vulnerability of mitochondria to metformin in the lentiform nuclei. When metformin causes encephalopathy, not only testing for serum lactic acidosis and performing routine magnetic resonance imaging but also evaluation of brain lactate accumulation by magnetic resonance spectroscopy should be required to elucidate the etiology.

•

Metformin-induced encephalopathy with lactate accumulation in lentiform fork sign was reported.

•

Lentiform nuclei might be more vulnerable to metformin than other organs.

•

This case suggested an etiology for the lentiform fork sign because metformin is a mitochondrial inhibitor.

Movement Disorders Due to Selective Basal Ganglia Lesions with Uremia

BACKGROUND

Basal ganglia (BG) lesions are rarely reported in patients with uremia and may manifest by movement disorders. However, their exact incidence and pathogenesis have not been extensively studied. This study aimed to determine the frequency, types, risk variables (clinical, laboratory, and imaging), and manifestations of BG lesions with uremia and patients' neurologic outcomes.

METHODS

This observational study included 70 adults (mean age: 45.87 ± 3.36 years; duration of uremia: 5.5 ± 1.5 years). They underwent extensive evaluations (clinical, laboratory, and neuroimaging) and had prospectively evaluated clinically every 3 months for 2 years. Repeated magnetic resonance imaging (MRI) brains were done to patients with movement disorders and correlated with their neurologic outcomes.

RESULTS

BG lesions were found in 15 patients (21.4%) and 6 (8.6%) had movement disorders [Parkinsonism (n = 4), choreo-dystonia (n = 1) and dystonia (n = 1)] after the onset of uremia (mean = 10 months). There were no characteristic risk variables that distinguished patients with movement disorders from those without. Five developed movement disorders prior to the period of the study and one was de novo. The majority was females and had diabetes and higher frequencies of abnormal renal dysfunction, metabolic derangements, and white matter hyperintensities in MRIs. Movement disorders persisted in all patients despite the resolution of neuroimaging in three patients.

CONCLUSIONS

There is no clear threshold for renal failure to result in movement disorders due to BG lesions. The clinical outcome is variables depending on each patient's comorbidities and complications. Persistent neuronal damage (due to uremic toxins/metabolic/nutritional and ischemic/microvascular factors) has been suggested as the cause of poor neurologic outcomes.

Linking chronic kidney disease and Parkinson's disease: a literature review

Chronic kidney disease (CKD) has been typically implicated in cardiovascular risk, considering the function the kidney has related to blood pressure, vitamin D, red blood cell metabolism, and electrolyte and acid-base regulation. However, neurological consequences are also attributed to this disease. Among these, recent large epidemiological studies have demonstrated an increased risk for Parkinson's disease (PD) in patients with CKD. Multiple studies have evaluated individually the association of blood pressure, vitamin D, and red blood cell dysmetabolism with PD, however, no study has reviewed the potential mechanisms related to these components in context of CKD and PD. In this review, we explored the association of CKD and PD and linked the components of the former to propose potential pathways explaining a future increased risk for PD, where renin-angiotensin system, oxidative stress, and inflammation have a main role. Potential preventive and therapeutic interventions based on these associations are also explored. More preclinical studies are needed to confirm the potential link of CKD conditions and future PD risk, whereas more interventional studies targeting this association are warranted to confirm their potential benefit in PD.

Alpha-Synuclein in the Gastrointestinal Tract as a Potential Biomarker for Early Detection of Parkinson's Disease

The primary pathogenesis associated with Parkinson's disease (PD) occurs in peripheral tissues several years before the onset of typical motor symptoms. Early and reliable diagnosis of PD could provide new treatment options for PD patients and improve their quality of life. At present, however, diagnosis relies mainly on clinical symptoms, and definitive diagnosis is still based on postmortem pathological confirmation of dopaminergic neuronal degeneration. In addition, the similarity of the clinical, cognitive, and neuropathological features of PD with other neurodegenerative diseases calls for new biomarkers, suitable for differential diagnosis. Alpha-synuclein (α-Syn) is a potential PD biomarker, due to its close connection with the pathogenesis of the disease. Here we summarize the currently available information on the possible use of α-Syn as a biomarker of early stages of PD in gastrointestinal (GI) tissues, highlight its potential to distinguish PD and other neurodegenerative diseases, and suggest alternative methods (primarily developed for other tissue analysis) that could improve α-Syn detection procedures or diagnostic methods in general.

The retina as a window to the basal ganglia: Systematic review of the potential link between retinopathy and hyperkinetic disorders in diabetes

There is evidence that glycemic fluctuations trigger vascular-mediated dysfunction in both the retina and the striatopallidal regions in patients with diabetes. The latter is associated with a variety of hyperkinetic disorders that are rare but disabling and potentially preventable. We conducted a systematic review of the potential association between diabetic retinopathy and the risk and prognosis of hyperkinetic disorders in patients with diabetes. We identified a total of 461 articles and 147 were eligible for review. Nine out of 147 articles (6.12%) reported 13 patients with information on diabetic retinopathy. Glycemic fluctuations were present at onset in 10 patients (77%) and retinopathy was present in nine of them (69.23%). The degree of retinopathy was reported in four patients. Two had severe, bilateral proliferative retinopathy, one had moderate-to-severe non-proliferative retinopathy and one had non-proliferative retinopathy. In the nine patients with retinopathy, hyperkinesia persisted, required higher doses of dopamine receptor antagonists or deep brain stimulation. Retinopathy was absent in four cases (30.77%). In these patients, hyperkinesia resolved spontaneously or with lower doses of dopamine receptor antagonists. Diabetic retinopathy could be an indirect marker of striatopallidal microangiopathy in patients with diabetes. The severity of retinopathy may be associated with increased risk or worse prognosis for patients who develop hyperkinetic disorders of the diabetic striatopathy spectrum. Early detection of retinopathy could identify patients in which avoiding glycemic fluctuations may prevent the development of striatopathy and hyperkinetic disorders.

Movement Disorders and Renal Diseases

Movement disorders often emerge from the interplay of complex pathophysiological processes involving the kidneys and the nervous system. Tremor, myoclonus, ataxia, chorea, and parkinsonism can occur in the context of renal dysfunction (azotemia and electrolyte abnormalities) or they can be part of complications of its management (dialysis and renal transplantation). On the other hand, myoglobinuria from rhabdomyolysis in status dystonicus and certain drugs used in the management of movement disorders can cause nephrotoxicity. Distinct from these well-recognized associations, it is important to appreciate that there are several inherited and acquired disorders in which movement abnormalities do not occur as a consequence of renal dysfunction or vice versa but are manifestations of common pathophysiological processes affecting the nervous system and the kidneys. These disorders are the emphasis of this review. Increasing awareness of these conditions among neurologists may help them to identify renal involvement earlier, take timely intervention by anticipating complications and focus on therapies targeting common mechanisms in addition to symptomatic management of movement disorders. Recognition of renal impairment in a patient with complex neurological presentation may narrow down the differentials and aid in reaching a definite diagnosis.

Chronic renal dysfunction, proteinuria, and risk of Parkinson's disease in the elderly

BACKGROUND

The roles of chronic kidney disease and proteinuria in the development of Parkinson's disease have not been widely studied. The objective of this study was to examine the associations of chronic renal dysfunction and proteinuria with the risk of PD in older adults using cohort data of the whole South Korean population.

METHODS

We included 3,580,435 individuals aged ≥65 years who had undergone health checkups provided by the National Health Insurance Service of South Korea between 2009 and 2012 and were followed until 2015. Multivariable Cox proportional hazards regression models were performed.

RESULTS

During a mean follow-up of 5.2 ± 1.3 years, 30,813 individuals (0.86% of the total population) developed PD. Lower estimated glomerular filtration rate and a higher degree of proteinuria on a dipstick test were associated with higher incidence probability of PD (log-rank P < 0.001). In Cox regression models, chronic renal dysfunction graded by estimated glomerular filtration rate (mL/min/1.73 m² ) was associated with increased risk of PD after adjusting for potential confounding variables; hazard ratio (95% confidence interval) was 1.13 (1.10-1.17) for estimated glomerular filtration rate 60-90, 1.36 (1.31-1.42) for estimated glomerular filtration rate 30-60, and 1.47 (1.32-1.63) for estimated glomerular filtration rate <30 (P for trend <0.001). Proteinuria ≥1+ was also associated with increased risk of PD development (hazard ratio, 1.12; 95% confidence interval, 1.06-1.18). Coexistence of chronic kidney disease and proteinuria showed an increased hazard ratio of 1.33 (95% confidence interval, 1.23-1.45) for PD occurrence.

CONCLUSIONS

Our findings suggest that chronic renal dysfunction and dipstick-positive proteinuria may be independent risk factors for the development of PD in older adults. © 2019 International Parkinson and Movement Disorder Society.

Unstable blood sugar levels as triggers for the syndrome of acute bilateral basal ganglia lesions in diabetic uremia: Two Taiwanese patients with unusual neuroimaging findings

The syndrome of acute bilateral basal ganglia lesions in diabetic uremia is uncommon and usually affects Asian patients. The underlying pathogenesis of this syndrome is not clear. We searched PUBMED using the keywords “bilateral basal ganglia”, “diabetic”, and “uremia”, and found a total of 34 cases from 1998 to 2016. In most cases, blood sugar levels were normal. Here we report two Taiwanese cases presenting with dyskinesias. In one case the syndrome was triggered by hyperglycemia, and in the other by severe hypoglycemia. Their neuroimaging findings were unusual as compared with previously reported cases, presenting as mixed hypo- and hyperintensity on T1-weighted magnetic resonance imaging. We think these new finding would shed some light on the underlying pathophysiology of this syndrome. For treatment, it is advisable to keep glucose levels as stable as possible in diabetic uremic patients to prevent this syndrome. A rapid correction of hyper- or hypoglycemia after the onset may help recovery.

•

Syndrome of acute bilateral basal ganglia lesions in diabetic uremia presenting with dyskinesias.

•

Hyperglycemia and hypoglycemia can trigger this syndrome.

•

Mixed hypo- and hyperintensity on T1-weighted MRI.

Uremic parkinsonism with atypical phenotypes and radiologic features

Uremic encephalopathy with bilateral basal ganglia lesions has been reported as an acute neurometabolic disease which shows reversible clinical course and brain imaging features. The exact nature and pathophysiology have not been well established. We encountered two patients who showed a relapsing and aggravating course and an atypical phenotype including parkinsonism with paroxysmal dystonic head tremor and acute onset monoparesis of the lower extremity. They also showed unusual radiological findings which revealed combined lesions in the basal ganglia and cortex, persistent hemorrhagic transformation, and focal ischemic lesion in the internal capsule. Herein, we present the unusual phenomenology with atypical radiologic findings and suggest the possible multifactorial pathogenesis of uremic encephalopathy.

Decreased dopamine transporter and receptor ligand binding in Parkinsonism with diabetic uremic syndrome

Here, we describe the case of a 47-year-old man with bilateral striatal lesions with diabetic uremia. Following 4 years of hemodialysis, the patient experienced sudden onset of rigidity, bradykinesia, gait disorder, and postural instability. Symptoms were remediated 2 months later, and were no longer responsive to levodopa approximately 1 year after the onset. Brain magnetic resonance imaging (MRI) during the acute phase showed T 2-weighted high signal edematous lesions in the bilateral striatum, subsequently developing into vacuolated lesions. A positron emission tomography (PET) scan using ((11)C)-labeled 2-carbomethoxy-3-(4-fluorophenyl) tropane [((11)C) CFT] and ((11)C)-labeled raclopride [((11)C) RAC] revealed significant decreases bilaterally in pre- and postsynaptic functions of the dopaminergic neurons. When we experience a case with bilateral putaminal destruction resulting in Parkinsonism, examination of the function of doperminergic neurons and dopamine receptors using molecular imaging is useful to predict levodopa response and prognosis.

Movement disorders in systemic diseases

Movement disorders, classically involving dysfunction of the basal ganglia commonly occur in neurodegenerative and structural brain disorders. At times, however, movement disorders can be the initial manifestation of a systemic disease. In this article we discuss the most common movement disorders which may present in infectious, autoimmune, paraneoplastic, metabolic and endocrine diseases. Management often has to be multidisciplinary involving primary care physicians, neurologists, allied health professionals including nurses, occupational therapists and less frequently neurosurgeons. Recognizing and treating the underlying systemic disease is important in order to improve the neurological symptoms.

Brain SPECT and MRI Findings in a Uremic Patient With Parkinsonism

Parkinsonism associated with basal ganglia pathology represents a rare complication in uremia patients, characterized by acute hyperkinetic or hypokinetic extrapyramidal movement disorders. We herein present brain SPECT and MR findings of uremic patients with end-stage renal failure exhibiting parkinsonian symptoms. The bilateral basal ganglia exhibited decreased uptake on SPECT, and abnormal signals on MR, suggesting pathology.

Chorea due to diabetic hyperglycemia and uremia: distinct clinical and imaging features

This study was undertaken to describe the clinical and imaging characteristics of patients with chorea associated with nonketotic hyperglycemia (C-NKH) in comparison with patients with chorea associated with uremia (C-URE). We retrospectively analyzed the clinical data of consecutive 10 C-NKH and five C-URE patients who were treated between January 1, 2001 and January 31, 2013. Women were more frequently affected by C-NKH (70% vs. 30%) and C-URE (80% vs. 20%) compared with men. The C-NKH patients demonstrated T1-hyperintense and inhomogeneous lesions in the basal ganglia, whereas C-URE patients demonstrated T2-hyperintense and homogeneous lesions in the basal ganglia. The mean time for chorea resolution after treatment was significantly shorter in C-NKH patients than in C-URE patients (4.4 ± 2.6 d vs. 73.8 ± 14.2 d, respectively; P = 0.005). The clinical and imaging features are remarkably different between C-NKH and C-URE patients, suggesting distinct pathogenic mechanisms.

Acute Chorea with Bilateral Basal Ganglia Lesions in Diabetic Uremia

Uremia is a syndrome of clinical and metabolic abnormalities, which develops in parallel with the deterioration of renal function. Uremic encephalopathy is one of many manifestations of acute or chronic renal failure. It is usually applied to patients with cortical involvement, such as confusion, seizure, tremor, myoclonus, or asterixis. Some cases of acute extrapyramidal movement disorders associated with bilateral basal ganglia lesions, especially parkinsonism have been reported in uremic patients. Here, we report a diabetic uremic patient who developed acute chorea associated with bilateral basal ganglia lesions.

Rare case of reversible acute symmetrical lesions of the bilateral Basal Ganglia associated with diabetic nephropathy and chronic renal failure

Reversible acute symmetrical basal ganglial lesion on magnetic resonance imaging and/or computed tomography in cases of diabetic nephropathy and chronic renal failure exhibiting acute onset of movement abnormalities like chorea is a very rare entity. It has characteristic clinical and imaging features. Only 29 cases are described in the literature, including the current one. These cases are predominantly Asian patients from the Far East and only one Asian Indian patient has been described. We report the second Asian Indian case of this condition and describe its various clinical and imaging features. Our aim is to educate the clinicians and radiologists about this condition, so that more such cases can be detected.

Increased risk of Parkinson's disease in patients with end-stage renal disease: a retrospective cohort study

BACKGROUND

Studies on dyskinesia and Parkinson's syndrome associated with chronic kidney disease or end-stage renal disease (ESRD) have been mainly limited to case reports or case series studies. This population-based study investigated the risk of Parkinson's disease in patients with ESRD.

METHODS

From a universal insurance claims database of Taiwan, we established a cohort of 8,325 adults with newly diagnosed ESRD from 1997 to 2010 without a history of Parkinson's disease. A control cohort of 33,382 insured subjects without a history of kidney disease or Parkinson's disease was also selected, with frequency matched for age, sex and index date of the patients with ESRD. Both cohorts were followed up until the end of 2010.

RESULTS

The Parkinson's disease incidence was 1.55-fold higher in the cohort with ESRD than in the comparison cohort (48.8 vs. 31.7 per 10,000 person-years) with an adjusted hazard ratio of 1.73 (95% confidence interval, 1.39-2.15). Sex-specific and age-specific analysis showed a higher relative risk for women and younger patients with ESRD compared to the control cohort.

CONCLUSIONS

ESRD is significantly associated with an increased risk of Parkinson's disease. Close surveillance for Parkinson's disease should be considered for patients with ESRD.

Diabetic uremic syndrome studied with cerebral MR spectroscopy and CT perfusion

Diabetic uremic syndrome (DUS) is an increasingly reported acute neurometabolic cerebral disease with characteristic clinical and imaging features. Clinical spectrum includes a wide range of movement disorders such as acute parkinsonism. Imaging studies show reversible (with hemodialysis) bilateral lesions in the lenticular nuclei. DUS pathophysiology has not been entirely clarified yet. Our case study shows certainly that LN lesions are characterized with increased lactate peak with MR spectroscopy and decreased perfusion in computerized tomography perfusion along with increased diffusion with apparent diffusion coefficient (ADC) mapping in the subacute phase of the syndrome. Abnormalities were almost normalized quickly after metabolic control by hemodialysis. Together with reports indicating that a deficit of glucose use exacerbated with acute increase of uremic toxins in bilateral LN, observed changes (lactate peak and hypoperfusion) led us to state that a primary metabolic depression may cause this syndrome. Metabolic depression is probably due to uncompensated uremic toxin accumulation related mitochondrial supression and/or dysfunction. This definition fits well to the other elements of DUS such as ADC evolution and marked lesion regression. Our single case study is not supportive of other previously credited mechanisms such as microvascular dysfunction related focal ischemia or hypoperfusion, prolonged uremic toxin related histotoxic hypoxia, central pontine myelinolysis-like demyelination and posterior leukoencephalopathy spectrum disorder related vasogenic edema.

[A case of subacute parkinsonism presenting as bilateral basal ganglia legions by MRI in diabetic uremic syndrome]

A 60-year-old male was admitted because he had developed tremulous movement in both upper and lower limbs and gait disturbance over the course of 3 months. He had been on continuous ambulatory peritoneal dialysis almost 1 year earlier due to end-stage diabetic nephropathy. A neurological examination revealed a mild disturbance of his consciousness, asterixis in the upper limbs, bilateral extensor plantar responses and parkinsonism, which were characterized by bradykinesia, akinesia, rigidity, and bilaterally tremors at rest. Cranial magnetic resonance imaging (MRI) revealed swollen bilateral basal ganglia legions, which appeared hyperintense on T2-weighted images. The patient was treated for metabolic acidosis and continued hemodialysis three times a week; however, the parkinsonism remained 1 year later. Follow-up MRI revealed decreased swelling of the basal ganglia, and the pattern of diffusion-weighted images and the apparent diffusion coefficient (ADC) map indicated vasogenic and cytotoxic edema in bilateral globus pallidus. The case was diagnosed as encephalopathy due to diabetic uremic syndrome, initially characterized by Wang et al. (2003). Only 17 cases with parkinsonism have been reported. Diabetic uremic syndrome is characterized by acute or subacute onset consciousness disturbance and movement disorders such as parkinsonism, chorea and the other extrapyramidal signs to various degrees related to bilateral lesions of the basal ganglia.

Increased risks of parkinsonism in the 3 years after chronic renal failure

AIMS

Movement disorders are one of the central nervous system complications in uremic patients. Asterixis, multifocal myoclonus, and restless leg syndrome are well-documented in this category. Acute parkinsonism, however, is only reported in rare series with a small number of cases. In this study, we investigated the risk for parkinsonism during a 3-year follow-up period after a diagnosis of uremia.

METHODS

The Longitudinal Health Insurance Database in Taiwan was utilised. We identified a total of 2862 patients who had visited ambulatory care centers with a diagnosis of chronic renal failure between 1999 and 2001 as the study cohort. We further randomly selected 14,310 enrollees matched with the study cohort in terms of gender, age, and year of their index visit for comparison. Each patient was individually tracked for 3 years to identify the occurrence of parkinsonism. Stratified Cox proportional hazard regressions (stratified by age and gender) were performed for analyses.

RESULTS

We found the annual incidence rates of parkinsonism to be 1.2% and 0.6% in the uremic and non-uremic groups, respectively. Furthermore, uremic patients were more vulnerable to developing parkinsonism with a 1.81-fold higher risk [95%CI = (1.21-2.71)] than the non-uremic group after adjusting for diabetes mellitus, which did not augment the risk.

CONCLUSIONS

The importance of raising awareness regarding the early symptoms of parkinsonism among patients with uremia is tied to its early identification, with timely aggressive dialysis being able to apply to slow the progression of the disease and its symptoms. Further study is warranted to elucidate the pathophysiology of uremic parkinsonism.

Lentiform Fork sign: a unique MRI picture. Is metabolic acidosis responsible?

BACKGROUND AND PURPOSE

Bilateral basal ganglia lesions are neither diagnostic nor pathognomonic of uremic encephalopathy (UE). Nonetheless, bilateral basal ganglia T2/FLAIR hyperintensities have been widely reported to be associated with UE. The aim of this study was to describe a unique neuroradiological sign seen on the MRI brain in UE, present a retrospective chart review of patients with UE over the past 10 years for evidence of similar MRI appearance, review literature for evidence of this sign, and generate a hypothesis to explain its pathophysiological basis.

METHODS

We describe a previously unreported and unique MRI picture, the Lentiform Fork sign, in a patient with UE. We conducted a focused retrospective chart review of patients with UE over the past 10 years, for evidence of similar MRI changes. We review literature (through PUBMED, OVID, and CENTRAL) for evidence of this sign and propose a hypothesis to explain the basis of this MRI sign.

RESULTS

We describe the Lentiform Fork sign in a patient with UE. Of our 21 retrospectively reviewed patients with UE who underwent MRI, only one had this sign. Literature review identified 22 patients with this sign who had various conditions, all associated with metabolic acidosis. Fourteen of these patients had documented evidence of severe metabolic acidosis. We propose the hypothesis that metabolic acidosis is the basis of this Lentiform Fork sign.

CONCLUSION

Lentiform Fork sign is a unique, previously unreported MRI picture that is seen not only in patients with UE but also in other conditions that result in metabolic acidosis, helping discriminate a specific etiology from the myriad of conditions that are lumped under the rubric of "basal ganglia hyperintensity." We propose the hypothesis that metabolic acidosis may be the key factor in the pathogenesis of this sign.

Acute extrapyramidal disorder with bilateral reversible basal ganglia lesions in a diabetic uremic patient: diffusion-weighted imaging and spectroscopy findings

Acute movement disorders associated with bilateral lesions in the basal ganglia are increasingly described in patients affected by diabetes and uremia. Pathophysiology has not been utterly understood yet, but it is likely to be multifactorial, with both ischemic/microvascular and metabolic/toxic factors determining the lesions and symptoms. We have studied a uremic diabetic patient who was admitted in emergency after presenting choreic movements, in which CT and MR, including diffusion-weighted imaging and spectroscopy, showed bilateral symmetric basal ganglia lesions with regression at follow-up. This is the first report in the literature describing spectroscopic findings in this condition.

Diffusion weighted MR imaging in non-infarct lesions of the brain

Diffusion weighted imaging (DWI) is a relatively new method in which the images are formed by the contrast produced by the random microscopic motion of water molecules in different tissues. Although DWI has been tried for different organ systems, it has been found its primary use in the central nervous system. The most widely used clinical application is in the detection of hyperacute infarcts and the differentiation of acute or subacute infarction from chronic infarction. Recently DWI has been applied to various other cerebral diseases. In this pictorial paper the authors demonstrated different DWI patterns of non-infarct lesions of the brain which are hyperintense in the diffusion trace image, such as infectious, neoplastic and demyelinating diseases, encephalopathies - including hypoxic-ischemic, hypertensive, eclamptic, toxic, metabolic and mitochondrial encephalopathies - leukodystrophies, vasculitis and vasculopathies, hemorrhage and trauma.