Abnormal thermography in Parkinson's disease.

BACKGROUND: An autonomic denervation and abnormal vasomotor reflex in the skin have been described in Parkinson's disease (PD) and might be evaluable using thermography with cold stress test. METHODS: A cross-sectional pilot study was undertaken in 35 adults: 15 patients with PD and abnormal [(123)I]-metaiodobenzylguanidine cardiac scintigraphy and 20 healthy controls. Baseline thermography of both hands was obtained before immersing one in cold water (3 ± 1 °C) for 2 min. Continuous thermography was performed in: non-immersed hand (right or with lesser motor involvement) during immersion of the contralateral hand and for 6 min afterward; and contralateral immersed hand for 6 min post-immersion. The region of interest was the dorsal skin of the third finger, distal phalanx. RESULTS: PD patients showed a lower mean baseline hand temperature (p = 0.037) and greater thermal difference between dorsum of wrist and third finger (p = 0.036) and between hands (p = 0.0001) versus controls, regardless of the motor laterality. Both tests evidenced an adequate capacity to differentiate between groups: in the non-immersed hand, the PD patients did not show the normal cooling pattern or final thermal overshoot observed in controls (F = 5.29; p = 0.001), and there was an AUC of 0.897 (95%CI 0.796-0.998) for this cooling; in the immersed hand, thermal recovery at 6 min post-immersion was lesser in patients (29 ± 17% vs. 55 ± 28%, p = 0.002), with an AUC of 0.810 (95%CI 0.662-0.958). CONCLUSIONS: PD patients reveal abnormal skin thermal responses in thermography with cold stress test, suggesting cutaneous autonomic dysfunction. This simple technique may be useful to evaluate autonomic dysfunction in PD.

Change of the melanocortin system caused by bilateral subthalamic nucleus stimulation in Parkinson's disease.

OBJECTIVES - Determine whether bilateral subthalamic nucleus stimulation (STN-DBS) in Parkinson's disease (PD) is associated with an increase in neuropeptide Y (NPY) and/or resistance to inhibition by leptin in relation to post-surgery weight gain. MATERIALS AND METHODS - This prospective study included 20 patients who underwent bilateral STN-DBS and 17 who refused surgery. Data were obtained at baseline, 3 and 6 months on neurological and nutritional status, including determination of body mass index (BMI) and serum NPY and leptin levels. RESULTS - NPY and leptin levels changed over time, with a distinct pattern. The BMI increase at 6 months was greater in the surgical group (5.5 ± 6.3% vs 0.5 ± 3.5%; P = 0.035). Medical group exhibited a reduction in leptin level (-2.0 ± 4.3 ng/ml) and a consequent increase in NPY level (72.4 ± 58.7 pmol/ml). However, STN-DBS patients showed an increase in leptin (3.1 ± 5.0 ng/ml; P = 0.001 vs medical group) and also in NPY (12.1 ± 53.6 pmol/ml; P = 0.022 vs medical group) levels, which suggests resistance to inhibition by leptin. Rise in NPY level correlated with higher stimulation voltages. CONCLUSIONS - Bilateral STN-DBS causes disruption of the melanocortin system, probably related to diffusion of the electric current to the hypothalamus. This mechanism may in part explain the weight gain of patients with PD after surgery.

[Diagnostic value of cardiac 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy in Lewy body disorders]. / Valor diagnóstico de la gammagrafía cardíaca con 123I-metaiodobenzilguanidina en las enfermedades con cuerpos de Lewy.

INTRODUCTION: Lewy body disorders such as Parkinson's disease (PD) and Lewy body dementia (LBD) are associated with cardiac sympathetic denervation, which can be visualized on 123I-MIBG scintigraphy. Our objectives were to study the diagnostic value of this technique in Lewy body disorders and its relationship with PD clinical variables. PATIENTS AND METHODS: We studied 90 patients: 51 with PD, 19 with LBD, 9 with multiple system atrophy (MSA) and 11 controls. Scintigraphy images were qualitatively evaluated and early and delayed heart-to-mediastinum ratios (HMR) were calculated. The main confounding factors (ischemic heart disease, diabetes, hypertension and drugs) were controlled by multivariate linear regression analysis. We investigated correlations between scintigraphy variables and PD variables. RESULTS: The delayed HMR, which showed better discriminative ability was 2.03 +/- 0.32 in controls, 1.37 +/- 0.30 in PD (p<0.001 vs controls), 1.47+/-0.45 in LBD (p=0.001 vs controls) and 1.69+/-0.28 in MSA (p=0.02 vs controls; p=0.004 vs PD). This ratio was influenced by PD/LBD diagnosis (beta= -0.638; p<0.001) and to a lesser degree, by ischemic heart disease (beta= -0.244; p=0.028). Optimal cut-off value between PD/LBD and controls was 1.71 (83% sensitivity and 82% specificity). Within the PD group, those with a family history of PD/LB showed higher delayed HMR values (1.65+/-0.34 vs 1.30+/-0.24 without history; p<0.001) and proportion with normal scintigraphy (56% vs 5%; p=0.001). CONCLUSIONS: Cardiac 123I-MIBG scintigraphy is useful in the diagnosis of Lewy body disorders, although its value in PD is conditioned by having a family history of PD.

[Diagnostic accuracy of the Phototest for cognitive impairment and dementia]. / Utilidad diagnóstica del Test de las Fotos (Fototest) en deterioro cognitivo y demencia.

INTRODUCTION: The recently developed Phototest is a simple, easy and very brief (<3 minutes) test with theoretical advantages over available dementia screening tests. Our objective was to evaluate its diagnostic accuracy under routine clinical conditions. MATERIAL AND METHODS: A phase II cross-sectional validation study of diagnostic tests was performed in a sample of 308 patients referred to a general neurology department and in a group of 70 healthy individuals. The diagnostic accuracy (DA) of the Phototest was assessed and compared with that of the Eurotest and a verbal fluency test (VFT) in relation to the clinical diagnosis of dementia (DEM) and cognitive impairment (CI) by calculating the area under the ROC curve (aROC) and determining Sensitivity (Se), Specificity (Sp) and likelihood ratios. RESULTS: The total sample comprised 225 subjects without CI (NOR), 58 with CI and without DEM and 95 with DEM. Phototest results showed a normal distribution in NOR subjects (33.4 +/- 3.9 [mean +/- standard desviation]) and were not influenced by educational variables. The DA of the Phototest for DEM and CI (0.95 +/- 0.01 [aRO C+/- Se]) was similar to that of the Eurotest and higher for both tests than that of the VFT. The cutoff points of 25/26 for DEM (Se=0.88 [0.80-0.94], Sp=0.90 [0.86- 0.93]) and 28/29 for CI (Se=0.90 [0.84-0.94], Sp=0.90 [0.83-0.93]) maximised the sum of Se and Sp. CONCLUSIONS: The Phototest is a very short test of easy application that is applicable to illiterate subjects, uninfluenced by educational variables and useful to identify CI and DEM in routine clinical practice.

[Sign of hyperdense and hyperintense anterior cerebral artery]. / Signo de la arteria cerebral anterior hiperdensa e hiperintensa.

INTRODUCTION: The sign of a hyperdense middle cerebral artery (MCA) in computed tomography (CT) scan, or hyperintense MCA in magnetic resonance imaging (MRI) has been associated with recent acute occlusion of the vessel. Hyperdense or hyperintense signs in the basilar and cerebral posterior arteries in association with acute infarct have also been reported. These signs may help to clarify localization and provide prognostic information, especially when the clinical findings are not clear or conclusive. We hereby report on a case of acute infarct in the anterior cerebral artery (ACA) territory with hyperdensity and hyperintensity of the affected vessel. CASE REPORT: This is a case report of a 74 year old male patient with vascular risk factors who had the acute onset of speech impairment and left side hemiparesis, evolving over the next several hours to include depression of the level of consciousness, mutism, and right leg paresis. The A2 segment of the right ACA was found to be hyperdense in CT scan without contrast, and hyperintense in the FLAIR-MRI respectively. MR-angiography showed occlusion of the probably dominant right ACA at the A2 segment shortly after its onset. CONCLUSIONS: The finding of a hyperdense and hyperintense ACA may be useful for diagnosis of acute stroke in the ACA territory, particularly in clinically ambiguous cases. To our knowledge, this is the first reported case of hyperdense and hyperintense ACA as an early sign of acute stroke. Its prognostic value in the ACA is thus far unknown.