Assessment of neurological manifestations in hospitalized patients with COVID-19.

BACKGROUND AND PURPOSE: The objective of this study was to assess the neurological manifestations in a series of consecutive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive patients, comparing their frequency with a population hospitalized in the same period for flu/respiratory symptoms, finally not related to SARS-CoV-2. METHODS: Patients with flu/respiratory symptoms admitted to Fondazione Policlinico Gemelli hospital from 14 March 2020 to 20 April 2020 were retrospectively enrolled. The frequency of neurological manifestations of patients with SARS-CoV-2 infection was compared with a control group. RESULTS: In all, 213 patients were found to be positive for SARS-CoV-2, after reverse transcriptase polymerase chain reaction on nasal or throat swabs, whilst 218 patients were found to be negative and were used as a control group. Regarding central nervous system manifestations, in SARS-CoV-2-positive patients a higher frequency of headache, hyposmia and encephalopathy always related to systemic conditions (fever or hypoxia) was observed. Furthermore, muscular involvement was more frequent in SARS-CoV-2 infection. CONCLUSIONS: Patients with COVID-19 commonly have neurological manifestations but only hyposmia and muscle involvement seem more frequent compared with other flu diseases.

Peripheral neuropathy is a common manifestation of mitochondrial diseases: a single-centre experience.

BACKGROUND AND PURPOSE: Peripheral neuropathy in mitochondrial diseases (MDs) may vary from a subclinical finding in a multisystem syndrome to a severe, even isolated, manifestation in some patients. METHODS: To investigate the involvement of the peripheral nervous system in MDs extensive electrophysiological studies were performed in 109 patients with morphological, biochemical and genetic diagnosis of MD [12 A3243G progressive external ophthalmoplegia (PEO)/mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS), 16 myoclonic epilepsy with ragged-red fibres (MERRF), four mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), 67 PEO with single or multiple deletions of mitochondrial DNA, 10 others]. RESULTS: A neuropathy was found in 49 patients (45%). The incidence was very high in MNGIE (100%), MELAS (92%) and MERRF (69%), whilst 28% of PEO patients had evidence of peripheral involvement. The most frequent abnormality was a sensory axonal neuropathy found in 32/49 patients (65%). A sensory-motor axonal neuropathy was instead detected in 16% of the patients and sensory-motor axonal demyelinating neuropathy in 16%. Finally one Leigh patient had a motor axonal neuropathy. It is interesting to note that the great majority had preserved tendon reflexes and no sensory disturbances. CONCLUSIONS: In conclusion, peripheral involvement in MD is frequent even if often mild or asymptomatic. The correct identification and characterization of peripheral neuropathy through electrophysiological studies represents another tile in the challenge of MD diagnosis.

Gender may be related to the side of the motor syndrome and cognition in idiopathic Parkinson's disease.

BACKGROUND: and Sex and cognitive profile may be related to the laterality of motor symptoms in idiopathic Parkinson's disease. INTRODUCTION: Parkinson's disease (PD) is well recognised as an inherently asymmetric disease with unilateral onset of motor symptoms. The laterality of motor symptoms may be linked to sex, clinical and demographic variables, and neuropsychological disorders. However, the available data are inconsistent. This study aimed to explore the potential association between the laterality of motor symptoms and clinical and demographic variables and deficits in specific cognitive domains. MATERIAL AND METHODS: We retrospectively recruited 97 participants with idiopathic PD without dementia; 60 presented motor symptoms on the left side and 37 on the right side. Both groups were comparable in terms of age, age at disease onset, disease duration, and severity of the neurological deficits according to the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr scale. RESULTS: Participants with left-side motor symptoms scored lower on the Schwab and England Activities of Daily Living scale. Our sample included more men than women (67% vs. 33%). Both sexes were not equally represented in the 2 groups: there were significantly more men than women in the group of patients with left-side motor symptoms (77% vs. 23%), whereas the percentages of men and women in the group of patients with right-side motor symptoms were similar (51% vs. 49%). Both groups performed similarly in all neuropsychological tasks, but women, independently of laterality, performed better than men in the naming task. CONCLUSION: We found a clear prevalence of men in the group of patients with left-side motor symptoms; this group also scored lower on the Schwab and England Scale. Female sex was predictive of better performance in the naming task. Sex should always be considered in disorders that cause asymmetric involvement of the brain, such as PD.

Polypharmacy is a determinant of hospitalization in Parkinson's disease.

OBJECTIVE: Patients with Parkinson's disease (PD) are at a higher risk of hospitalization and recurrent hospitalizations, with consequent complications. Polypharmacy is associated with several adverse outcomes, including hospitalization, increased length of hospital stay, and mortality. The aim of this study was to evaluate among patients with PD the association between the number of medications and incident hospitalizations. PATIENTS AND METHODS: We analysed the data of 165 patients with Parkinson's disease attending a geriatric Day Hospital who were enrolled in a cohort study and followed for a median of two years. RESULTS: Over the follow-up, 46 participants (46%) were hospitalized at least one time; multiple admissions were observed in 12 subjects (7%). The median number of agents was 5 (4-7). In Cox regression, the number of drugs was associated with increased hospitalization rates (HR=1.23; 95% CI=1.06-1.43), also after excluding non-neurological medications (HR=1.18; 95% CI=1.01-1.38). Using Poisson regression, polypharmacy (i.e., use of >5 drugs) predicted the number of repeated hospitalizations (IRR=2.62; 95% CI=1.28-5.36; p=.008). CONCLUSIONS: Among patients with PD, the number of daily medications is associated with increased risk of hospitalization; an increasing number of drugs is associated with increasing number of hospitalizations.

Gender may be related to the side of the motor syndrome and cognition in idiopathic Parkinson's disease.

BACKGROUND: and Sex and cognitive profile may be related to the laterality of motor symptoms in idiopathic Parkinson's disease. INTRODUCTION: Parkinson's disease (PD) is well recognised as an inherently asymmetric disease with unilateral onset of motor symptoms. The laterality of motor symptoms may be linked to sex, clinical and demographic variables, and neuropsychological disorders. However, the available data are inconsistent. This study aimed to explore the potential association between the laterality of motor symptoms and clinical and demographic variables and deficits in specific cognitive domains. MATERIAL AND METHODS: We retrospectively recruited 97 participants with idiopathic PD without dementia; 60 presented motor symptoms on the left side and 37 on the right side. Both groups were comparable in terms of age, age at disease onset, disease duration, and severity of the neurological deficits according to the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr scale. RESULTS: Participants with left-side motor symptoms scored lower on the Schwab and England Activities of Daily Living scale. Our sample included more men than women (67% vs. 33%). Both sexes were not equally represented in the 2 groups: there were significantly more men than women in the group of patients with left-side motor symptoms (77% vs. 23%), whereas the percentages of men and women in the group of patients with right-side motor symptoms were similar (51% vs. 49%). Both groups performed similarly in all neuropsychological tasks, but women, independently of laterality, performed better than men in the naming task. CONCLUSION: We found a clear prevalence of men in the group of patients with left-side motor symptoms; this group also scored lower on the Schwab and England Scale. Female sex was predictive of better performance in the naming task. Sex should always be considered in disorders that cause asymmetric involvement of the brain, such as PD.

Laterality in Parkinson's disease may predict motor and visual imagery abilities.

Experimental evidence suggests that motor imagery (MI) engages the same neural substrates supporting actual motor activities and is likely impaired when such substrates are damaged, as in Parkinson's disease (PD). MI intuitively relies on visual imagery (VI), because mental simulations of physical movements depend on the visual retrieval of these movements. Although VI is generally considered a right hemispheric function, the hemispheric dominance of MI is still in dispute. Disparities in sidedness of motor disturbances are a distinctive feature of PD, and recent findings indicate that such disparities may similarly characterize cognition. Specifically, the deficits observed may depend upon which hemisphere is principally involved. Essentially, MI and VI are cognitive tasks subject to differential impairment and reflecting the prevalence of hemispheric impairment in PD. Motor imagery (assessed by the Vividness of Motor Imagery Questionnaire [VMIQ]) and VI (assessed by the Vividness of Visual Imagery Questionnaire [VVIQ] and Test of Visual Imagery Control [TVIC]) were examined in patients with asymmetric PD and in healthy elderly control subjects (HC group). VMIQ scores were similar in PD laterality subsets and the HC group, but VVIQ scores were significantly lower in both PD groups compared with the HC group. TVIC scores were significantly lower in the presence of left motor (right hemispheric) impairment and were predictive of left motor (right hemispheric) impairment. We suspect that MI is strongly reliant on VI and that language may mediate these two functions, to the extent that both are evoked through verbal stimuli. Working memory, both visual and verbal, is also involved in MI and VI tasks. Without due attention to laterality of symptoms, any training incorporating MI and VI may not deliver expected outcomes in the setting of asymmetric PD symptomatology.

Cochlear dysfunction in IDDM patients with subclinical peripheral neuropathy.

OBJECTIVE: To investigate the function of the auditory pathway from the cochlea to the auditory cortex in subjects with IDDM. RESEARCH DESIGN AND METHODS: Brain stem, middle-, and long-latency auditory-evoked responses and evoked otoacoustic emissions were measured in 48 normally hearing IDDM patients and in age- and sex-matched nondiabetic subjects. Peripheral neuropathy was diagnosed by nerve conduction velocity (NCV) at the peroneal and sural nerves. Auditory brain stem responses (ABRs) reflect auditory pathway function within the brain stem; middle-latency responses (MLRs) and long-latency responses (LLRs) originate from the auditory cortex; and evoked otoacoustic emissions (EOAEs) give objective information about preneural, mechanical elements of the cochlear function. RESULTS: A subclinical peripheral neuropathy was found in 12 diabetic patients. We found higher latencies of waves I (t = 4.4, P < 0.0001), III (t = 3.7, P = 0.0004), and V (t = 2.7, P = 0.008) of ABRs in diabetic patients (I: 1.7 +/- 0.13 ms; III: 3.9 +/- 0.17 ms; V: 5.7 +/- 0.24 ms), compared with those of the control group (I: 1.6 +/- 0.13 ms; III: 3.7 +/- 0.18 ms; V: 5.6 +/- 0.17 ms). However, neither central transmission time (i.e., the wave interpeak I-V) nor MLRs and LLRs were found to be significantly different in diabetic and control subjects. Mean EOAE amplitude was found to be significantly reduced (F = 4.2, P = 0.02) in diabetic patients with a reduced NCV (7.6 +/- 3.9 dB; Scheffé test: P = 0.03), but not in those without neuropathy (9.1 +/- 4.2 dB), compared with the control group (10.8 +/- 3.1 dB). No correlations were found between duration of diabetes and EOAEs or between sural NCV and peroneal NCV and metabolic control. EOAEs were not correlated with peroneal and sural NCVs. CONCLUSIONS: Our results indicate that the early preneural dysfunction of cochlear receptors causes a prolonged activation of the peripheral portion of the auditory pathway, while signal conduction along the central auditory pathway was shown to be normal in diabetes.

Multiperspective assessment of carpal tunnel syndrome: a multicenter study. Italian CTS Study Group.

OBJECTIVE: To assess the clinical and neurophysiologic dissociation often observed in clinical practice, and to improve patient evaluation for diagnosis of carpal tunnel syndrome (CTS). METHODS: The Italian CTS Study Group studied 1,123 idiopathic CTS hands with multiple measurements-clinical, neurophysiologic, and patient-oriented-of CTS. RESULTS: Clinical and neurophysiologic relationships were very strong when the clinical picture was evaluated by the hand functional measurements, with an exponential increase in functional impairment as the classification of neurophysiologic severity progressed. Conversely, symptoms and pain did not increase as the classification of neurophysiologic severity progressed: 1) A large part of the CTS population complained of severe symptoms, although minimal functional impairment and minimal or no electrophysiologic abnormalities were observed; and 2) symptoms improved in the patients with more severe neurophysiologic and clinical examination scenarios. CONCLUSIONS: Multiperspective and multimeasurement assessment, even when using a validated patient-oriented tool, provided interesting information that confirmed and clarified the clinical neurophysiologic dissociation often observed in carpal tunnel syndrome (CTS) patients. Furthermore, CTS appeared to be an ideal model for evaluating the importance of patient-oriented measurement.

Clinical heterogeneity of seronegative myasthenia gravis.

We studied 38 patients affected by seronegative myasthenia gravis (SNMG) with age at the onset of the disease ranging from 6 to 66 yr. Clinical follow-up lasted at least 2 yr. Patients' lymphocyte cultures showed in no case anti-acetylcholine receptor antibody production; HLA associations did not differ significantly from those in seropositive MG. In most cases (33 out of 38) the disease differed from seropositive MG only in the low incidence of thymic pathology. In five cases the clinical picture was characterized by prevalent involvement of ocular and bulbar muscles and by a more stable course. These last group of patients did not respond satisfactorily to immunosuppressants, but they clearly improved with plasma-exchange. Mice injected with plasma IgG from four patients (two with typical clinical picture and two with prevalent oculobulbar involvement) showed a defect of neuromuscular transmission. In our experience, SNMG is a heterogeneous disease. A humorally mediated pathogenesis appears to be operating in both groups of patients we described.

Multiple paraneoplastic diseases associated with thymoma.

Here we report a patient with a lymphoepithelial thymoma who developed in chronological sequence limbic encephalitis, neuromyotonia and myasthenia gravis. The patient presented with limbic encephalitis associated with an invasive thymoma and improved after surgery and cytotoxic therapy. Two months after thymectomy, neuromyotonia associated with hyperhidrosis and mild motor neuropathy occurred and the patient was given plasma-exchange and prednisone therapy. Five months later he developed mild generalised myasthenia gravis. Anti-acetylcholine receptor antibodies, previously repeatedly negative, were found positive at the onset of clinical signs of myasthenia gravis.

Peripheral neuropathy with hypomyelinating features in adult-onset Krabbe's disease.

We describe three brothers suffering from Krabbe's disease with onset in the fifth decade. The proband showed a complete deficiency of leukocyte enzyme galactocerebrosidase and was found to be heterozygous for two previously described mutations: G > A809 and 502T/del consisting of a 30 kb deletion. In all three brothers the neurological examination showed features of asymmetrical peripheral neuropathy associated with pyramidal signs and the electrophysiological examination showed a generalized slowing of nerve conduction velocities. Two patients died at 59 and 61 years of age due to respiratory failure. Both the proband and his brother underwent a sural nerve biopsy. In the former the most striking finding was the presence of uniformly thin myelin sheaths without evidence of demyelination; a complete absence of fibers was found in the latter. Our findings confirm that peripheral neuropathy may be the presenting feature of late-onset Krabbe's disease. Hypomyelination rather than demyelination may represent the distinguishing pathological finding of this condition.

Hereditary motor and sensory neuropathy with deafness, mental retardation, and absence of sensory large myelinated fibers: confirmation of a new entity.

We describe two brothers, 11 and 13 years old, respectively, with an early-onset hereditary motor and sensory neuropathy, deafness, and mental retardation. Electrophysiological studies showed marked reduction of motor and sensory conduction velocity and absence of sensory action potentials. Sural nerve biopsy, performed in both patients, showed absence of large myelinated fibers with normal density of small myelinated fibers without axonal degeneration. Signs of demyelination were found only in the younger patient. We suggest that motorsensory neuropathy associated with deafness and mental retardation with absence of large myelinated fibers on sural nerve biopsy represents a distinct clinicopathological entity, which is transmitted in families probably as an autosomal recessive trait.

When is there a full recovery for a myasthenia gravis patient?

A myasthenia gravis (MG) patient who seems to have recovered can later have recurrence of myasthenic signs. Clearly clinical remission does not always correspond to the normalization of all the factors involved in the pathogenesis of the disease. In ten patients who had apparently recovered from MG, electromyographic tests of repetitive supramaximal stimulation were performed and the anti-acetylcholine receptor (anti-AChR) antibody was assessed. In two of the ten patients all these tests were normal, thus showing lack of electromyographic myasthenic fatigability and the absence of circulating anti-AChR antibodies. Our hypothesis is that for these two subjects the risk of a recurrence of MG is lower than for the others.

Ocular palsies in the absence of other neurological or ocular symptoms: analysis of 105 cases.

We studied prospectively 105 unselected patients complaining of ptosis and/or diplopia due to extrinsic ophthalmic muscle palsies without other neurological signs. All patients underwent the same diagnostic protocol. The presenting symptoms were: ptosis, 35 patients (33%); diplopia, 27 patients (26%); ptosis and diplopia, 43 patients (41%). The oculomotor nerve was most frequently involved, followed by the abducens nerve. The final diagnoses were: ocular myasthenia, intracranial and/or orbital pathology, thyroid ophthalmopathy, diabetic ophthalmoplegia, mitochondrial myopathy, oculopharyngeal muscular dystrophy. In 26 patients (25%) the cause remained undetermined. Our study confirms the difficulty of establishing an aetiological diagnosis in patients with isolated ocular palsies.

Hereditary coproporphyria: unusual nervous system involvement in two cases.

Two cases of hereditary coproporphyria showed unusual nervous system involvement, one epilepsy with onset in childhood, and the other chronic central and peripheral nervous system damage. The literature is briefly discussed.

Quantitative EMG findings at different force levels in patients with myasthenia gravis.

Quantitative electromyography, comprising manual motor unit potential analysis at weak effort and turns/amplitude analysis at 30% of maximum force were performed in the brachial biceps muscle of 17 patients with myasthenia gravis (MG). Findings simulating myopathic and less often neurogenic changes were observed in seven out of 17 patients, suggesting that the myasthenic muscle may have random block of muscle fibres, functional block of the main part or whole motor units or a changed recruitment pattern. In addition, turns/amplitude analysis was performed at low force levels (10% of maximum force) both before and after a provocative manoeuvre consisting of a maximum effort sustained for 1 min, and at maximum force at the beginning and at the end of the provocation itself. Turns/amplitude analysis at low force failed to differentiate MG patients from controls. The relative change of ratio of turns to mean amplitude calculated from 10% to maximum force (at the beginning of the provocative manoeuvre) was increased in seven out of eight patients compared to the controls. This last finding seems to be useful in differentiating MG patients from patients with myopathy.

Quantitative needle electromyography during sustained maximal effort.

We describe changes in time domain as well as in frequency domain of the electromyographic (EMG) signal during sustained maximal effort. The anterior tibial muscle in five subjects and the brachial biceps muscle in eight subjects were examined with needle electrodes. The forces exerted decreased exponentially with time to ∼50% of the initial values after 1 min of sustained maximal effort. The mean and median power frequency declined exponentially with time. The decrease in number of spikes (turns, zero crossings) and amplitude (mean amplitude, integrated electrical activity) of the electrical activity in fatigued muscle, as compared with initial values can be explained in part by a dropout of some motor units and a decrease in firing rate. During the first minute, a decrease in number of turns and an increase in amplitude occurred in fatigued muscle as compared with values at the same force level in fresh muscle, probably owing to a decrease in conduction velocity along the fatigued muscle fiber and synchronous firing. This was consolidated by a linear relationship between the decrease in number of turns and the decrease in mean power frequency. After the first minute, a continued increase in amplitude only suggested contractile element fatigue. This order of physiologic changes was the same as that previously observed at sustained submaximal force.

Carpal tunnel syndrome: neurophysiological results of surgery based on preoperative electrodiagnostic testing.

Fifty-three hands with carpal tunnel syndrome had pre- and postoperative evaluations of median nerve distal motor latency (from wrist to thenar muscles) and orthodromic sensory nerve conduction velocity (from thumb and middle finger to wrist). At 6 months we observed a neurophysiological return to normal in all cases with normal preoperative distal motor latency and in about 50% of the hands with preoperative distal motor latency between 4 and 6 ms. Prolongation of the distal motor latency over 6 ms was not followed by return to neurophysiological normality, although some degree of sensory function was restored in the majority of cases.