Acute porphyrias - A neurological perspective.

Acute hepatic porphyrias (AHP) can cause severe neurological symptoms involving the central, autonomic, and peripheral nervous system. Due to their relative rarity and their chameleon-like presentation, delayed diagnosis and misdiagnosis are common. AHPs are genetically inherited disorders that result from heme biosynthesis enzyme deficiencies and comprise four forms: acute intermittent porphyria (AIP), variegate porphyria (VP), hereditary coproporphyria (HCP), and ALA-dehydratase porphyria (ALADP). Depending on the clinical presentation, the main differential diagnoses are Guillain-Barré syndrome and autoimmune encephalitis. Red flags that could raise the suspicion of acute porphyria are neurological symptoms starting after severe (abdominal) pain, in association with reddish urine, hyponatremia or photodermatitis, and the presence of encephalopathy and/or axonal neuropathy. We highlight the diagnostic difficulties by presenting three cases from our neurological intensive care unit and give a comprehensive overview about the diagnostic findings in imaging, electrophysiology, and neuropathology.

Combining viscoelasticity, diffusivity and volume of the hippocampus for the diagnosis of Alzheimer's disease based on magnetic resonance imaging.

Dementia due to Alzheimer's Disease (AD) is a neurodegenerative disease for which treatment strategies at an early stage are of great clinical importance. So far, there is still a lack of non-invasive diagnostic tools to sensitively detect AD in early stages and to predict individual disease progression. Magnetic resonance elastography (MRE) of the brain may be a promising novel tool. In this proof-of-concept study, we investigated whether multifrequency-MRE (MMRE) can detect differences in hippocampal stiffness between patients with clinical diagnosis of dementia due to AD and healthy controls (HC). Further, we analyzed if the combination of three MRI-derived parameters, i.e., hippocampal stiffness, hippocampal volume and mean diffusivity (MD), improves diagnostic accuracy. Diagnostic criteria for probable dementia due to AD were in line with the NINCDS-ADRDA criteria and were verified through history-taking (patient and informant), neuropsychological testing, routine blood results and routine MRI to exclude other medical causes of a cognitive decline. 21 AD patients and 21 HC (median age 75 years) underwent MMRE and structural MRI, from which hippocampal volume and MD were calculated. From the MMRE-images maps of the magnitude |G*| and phase angle φ of the complex shear modulus were reconstructed using multifrequency inversion. Median values of |G*| and φ were extracted within three regions of interest (hippocampus, thalamus and whole brain white matter). To test the predictive value of the main outcome parameters, we performed receiver operating characteristic (ROC) curve analyses. Hippocampal stiffness (|G*|) and viscosity (φ) were significantly lower in the patient group (both p < 0.001). ROC curve analyses showed an area under the curve (AUC) for | G*| of 0.81 [95%CI 0.68-0.94]; with sensitivity 86%, specificity 67% for cutoff at |G*| = 980 Pa) and for φ an AUC of 0.79 [95%CI 0.66-0.93]. In comparison, the AUC of MD and hippocampal volume were 0.83 [95%CI 0.71-0.95] and 0.86 [95%CI 0.74-0.97], respectively. A combined ROC curve of |G*|, MD and hippocampal volume yielded a significantly improved AUC of 0.90 [95%CI 0.81-0.99]. In conclusion, we demonstrated reduced hippocampal stiffness and reduced hippocampal viscosity, as determined by MMRE, in patients with clinical diagnosis of dementia of the AD type. Diagnostic sensitivity was further improved by the combination with two other MRI-based hippocampal parameters. These findings motivate further investigation whether MMRE can detect decreased brain stiffness already in pre-dementia stages, and whether these changes predict cognitive decline.

Favorable outcome of interferon-beta associated thrombotic microangiopathy following treatment with corticosteroids, plasma exchange and rituximab: A case report.

Thrombotic microangiopathy (TMA) is a rare but increasingly recognized complication of interferon-beta therapy, which can be associated with serious sequelae. We report on a 53-year-old woman with a longstanding history of relapsing-remitting multiple sclerosis, who developed TMA after 15 years of high-dose treatment with subcutaneous interferon-beta-1a. The patient presented with headaches, an epileptic seizure, confusion, and arterial hypertension. Laboratory findings included thrombocytopenia and hemolytic anemia. Despite of severe clinical manifestations and pronounced laboratory abnormalities, therapy with corticosteroids, plasma exchange and rituximab was associated with a favorable outcome and return to her premorbid level of functioning.

GAD Antibody-Associated Late-Onset Cerebellar Ataxia in Two Female Siblings.

BACKGROUND: Anti-glutamic acid decarboxylase antibody (GAD-ab)-associated cerebellar ataxia is a rare neurological disorder characterized by cerebellar symptoms concomitant with high GAD-ab levels in serum and cerebrospinal fluid (CSF). CASE REPORT: We report on 2 female siblings (aged 74 and 76 years) presenting with gradual progression of rotational vertigo, gait ataxia and vertical diplopia, continuously progressing for 6 months and 6 years, respectively. Autoimmune laboratory examinations showed remarkably increased serum and CSF GAD-ab levels. Their medical histories revealed late-onset type 1 diabetes mellitus (T1DM) and other concomitant autoimmune disorders (Grave's disease, Hashimoto's thyroiditis). Cerebral MRI and laboratory examinations were unremarkable. The diagnosis of GAD-ab-associated cerebellar ataxia with particular brainstem involvement was established in both women. After the exclusion of an underlying malignancy, immunosuppressive therapy has been initiated in both patients, which resulted in stabilization in one and in clinical improvement in the other patient. DISCUSSION: The unique association of autoantibody-mediated cerebellar ataxia and late-onset T1DM in 2 siblings with similar clinical and paraclinical phenotypes strengthens the concept that hereditary factors might play a relevant role also in autoimmune diseases so far considered to be sporadic. Moreover, the occurrence of continuous vertical diplopia broadens the clinical spectrum of GAD-ab-associated neurological syndromes.

Quantification of target population for ultrasound enhanced thrombolysis in acute ischemic stroke.

BACKGROUND AND PURPOSE: Insonation of the occluded target vessel (sonothrombolysis) has been reported to increase the effect of intravenous thrombolysis in ischemic stroke. Its use has predominantly been described in middle cerebral artery (MCA) occlusions. Sufficient insonation conditions are a mandatory precondition. The impact of these limitations on eligibility rates for sonothrombolysis has not been reported so far. METHODS: Consecutive patients treated with rt-PA and examined by either CT- or MR-angiogram before treatment and by transcranial color-coded duplex sonography (TCCS) during inhospital stay were identified retrospectively at three hospitals from ongoing data registries. RESULTS: One-hundred and seventy-nine patients (age [years], median [IQR] = 75 [65-83]; 42% female; NIH Stroke Scale [NIHSS], median [IQR] = 10 [6-17]) were analyzed. MCA occlusions were detected in 39% of patients (N = 69) with 48 (27%) occlusions in the proximal M1-segment and 21 (12%) in a distal M2-segment. Arterial occlusions others than MCA were seen in an additional 9% (N = 16). TCCS (without contrast agent) revealed sufficient bone windows in 70% of patients with MCA occlusions (N = 48) corresponding to 27% of all patients treated with thrombolysis. CONCLUSION: Conventional sonothrombolysis is restricted to a minority of stroke patients suitable for intravenous thrombolysis. Extending the applicability by utilization of ultrasound contrast agents and targeting non-MCA-occlusions warrants further evaluation.

Impact of hospital admission during nonworking hours on patient outcomes after thrombolysis for stroke.

BACKGROUND AND PURPOSE: Whether the time of hospital admission is relevant for short-term outcome after stroke is under debate and may depend on care facilities. METHODS: We retrospectively analyzed medical records from patients who received thrombolytic therapy within 4.5 hours of stroke onset in a stroke unit of the Charité-University Hospital Berlin (Charité; n=291) or within the stroke telemedicine (TEMPiS) network, comprising 12 community hospitals with telestroke units in Bavaria (n=616). RESULTS: Thrombolytic therapy was administered during nonworking hours in 59.5% (Charité) and 55.0% (TEMPiS) of patients. A trend toward a lower rate of symptomatic intracranial hemorrhage (3.4% versus 9.2%; P=0.053), clinical worsening (11.9% versus 19.7%; P=0.079), and 7-day mortality (3.4% versus 8.7%; P=0.073) after admission during working hours was seen at Charité. However, multivariable analysis did not show a significant impact of the time of admission on clinical worsening, symptomatic intracranial hemorrhage, or 7-day mortality in both cohorts. Thrombolysis based on brain computed tomography instead of magnetic resonance imaging (odds ratio=4.98, 95% CI, 1.09 to 22.7) and more severe National Institutes of Health Stroke Scale score on admission (odds ratio=1.15 per point; 95% CI, 1.07 to 1.24) were associated with 7-day mortality at Charité. National Institutes of Health Stroke Scale score on admission (odds ratio=1.13 per point; 95% CI, 1.06 to 1.19) and older age (odds ratio=1.05 per year; 95% CI, 1.004 to 1.09) were correlated with 7-day mortality in TEMPiS. National Institutes of Health Stroke Scale on admission was the only independent predictor of symptomatic intracranial hemorrhage or clinical worsening in both cohorts. CONCLUSIONS: The majority of stroke patients received thrombolysis during nonworking hours. The time of hospital admission did not significantly influence the short-term outcome after thrombolysis.