2019-novel Coronavirus disease (COVID-19) is a global health problem that affected >2.000.000 people in the world. Although the main component of the disease is pulmonary disturbances, recent reports suggested neurological manifestations. Neurological complications have been rarely reported with other Coronavirus associated diseases. In this short review, we would like to draw attention to COVID-19-related neurological symptoms. Heath-care providers should be aware that COVID-19 can associate neurological manifestations.

Objective: Neuropathy is seen in approximately 70% of patients in the predialysis stage; it is more common in individuals with pruritus, which may be an indicator of neuropathy. The aim of this study was to evaluate the presence of neuropathy and pruritus in the predialysis stage. Methods: The study included 60 patients in the predialysis stage and 30 volunteer controls. Neuropathic symptoms and severity and frequency of itching were recorded. The polyneuropathy (PNP) protocol and sympathetic skin responses (SSRs) were examined. Results: Electromyographic PNP was detected in 28.3% of the patients and pruritus in 36.7%. There was no significant difference in terms of neuropathy and SSR between the groups with and without pruritus (P > 0.05). Body mass index (BMI,P < 0.05) and uric acid levels (P = 0.022) were higher in the group with pruritus. The group in the predialysis stage was divided into two groups according to the stages. There was no difference between the groups in terms of neuropathy and pruritus (P > 0.05), whereas the amplitude and velocity of the median nerve, amplitude and velocity of the tibial nerve, amplitude of the sural nerve, and velocity of the peroneal nerve motor were found to be higher in the control group than in the two groups in the predialysis stage. Furthermore, a prolongation of the distal latency median motor nerve was found in two groups in the predialysis stage compared with the control group (P > 0.05). There was no significant difference between the two groups in terms of the presence of neuropathic symptoms and pruritus (P > 0.05). Conclusion: More than one-third (36.7%) of the patients had pruritus. Increased BMI and uric acid levels showed that it could be important to evaluate the patients in the predialysis stage.

Objective: Dopaminergic treatment is proved to ameliorate motor deficits in Parkinson's disease (PD); however, it could have negative effects on behavior and cognition, including impulse controlling and decision-making. We aimed (1) to investigate the decision-making and impulse-control disorders (ICDs) of PD patients and their correlations with sociodemographical and clinical variables, dopaminergic treatment in particular, and (2) to determine the relation of decision-making with ICDs. Methods: The sample of 39 patients with PD and 37 healthy controls underwent cognitive tests and the task which analyzed decision-making (Iowa Gambling Task [IGT]). Besides assessing motor and nonmotor symptoms of patients with PD, ICDs were also scanned using the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease. Results: Although patients with PD performed similarly to healthy controls on IGT, decision-making profile in PD related to clinical variables: dopaminergic treatment and duration of illness. In addition to this younger age of onset, higher dose of dopamine agonists, longer duration of illness, and impaired decision-making were together accounted for a substantial amount of variance in impulsive behaviors. Conclusions: Dopaminergic medication likely contributes to the impairment in decision-making, which may be the underlying mechanism of ICDs. Further studies will be necessary to understand the potential implications of this finding.

Objectives: Intermittent hypoxia resulting in endothelial dysfunction in microvascular circulation constitutes one of the mechanisms underlying complications of obstructive sleep apnea syndrome (OSAS), such as hypertension and atherosclerosis. The role of intermittent hypoxia on peripheral nerves, however, is still debated. Here, we designed a study in patients with OSAS to investigate different levels of the central and peripheral nervous systems, in order to delineate what kind of pathologic substrate was present, if any, and at which level of the neuromuscular pathway. Methods: A total of 20 patients with OSAS and 18 sex- and age-matched healthy controls were enrolled in our study. All participants underwent nerve conduction studies (NCSs) to analyze peripheral nerves, evoked potentials for somatosensory, visual evoked potential (VEP) and brainstem auditory pathways, blink reflex studies to analyze brainstem and subcortical structures, and transcranial magnetic stimulation to analyze the motor cortex and corticospinal pathway. Results: A comparison of NCSs between the two groups showed that the motor amplitudes of the ulnar nerve (P = 0.015) and sensory amplitudes of the sural nerve (P = 0.026) were significantly smaller in the OSAS group than those in the control group. The mean P100 amplitudes of VEP responses were 7.11 ± 2.73 μV in the OSAS group and 9.75 ± 3.52 μV in the control group (P = 0.022). In correlation analysis, the amplitude of P100 responses was positively correlated with the lowest oxygen saturation (P = 0.026). Conclusion: Our results confirmed the presence of generalized axonal involvement in the peripheral nervous system in OSAS, probably secondary to chronic intermittent hypoxemia.

Objective: Chronic inflammatory demyelinating polyneuropathy (CIDP) is a treatable disease; therefore, accurate diagnosis and detection of coexisting disorders are very important. Some authors have reported that CIDP was more frequently observed in patients with diabetes mellitus when compared with the population in general. Vitamin E deficiency leads to demyelinating neuropathy, and Vitamin E supplementation ensures clinical and electrophysiological recovery. In this study, identifying the association between insulin resistance, Vitamin E deficiency, and CIDP is aimed. Materials and Methods: Thirty-three patients with CIDP and forty healthy controls were evaluated. Two groups were compared in terms of insulin resistance and Vitamin E level status. Results: A statistically significant difference was not found between CIDP and control groups as for the distribution of mean ages, genders, Homeostatic Model Assessment Index values, impaired fasting glucose, and a statistically significant difference was not found between CIDP and control groups as for Vitamin E deficiency. Conclusion: Our study could not reveal any evidence about insulin resistance and Vitamin E deficiency in CIDP patients.

Objectives: This study assesses the validity and reliability of the Turkish version of the Mig-SCog scale used to determine and monitor the cognitive functions of migraine patients during attacks. Methods: After completion of the translation process, for this validity and reliability study the Mig-SCog was administered to a total of 154 migraine patients (91 without aura, 32 with aura, and 31 chronic migraine patients) presenting to the Neurology Clinic of Istanbul Medipol University University. Internal consistency of the factors and the instrument as a whole were evaluated using Cronbach's alpha coefficient and an alpha value >0.60 was considered acceptable. Results: As in the original, the result of factor analysis found a good fit for a 4-factor structure of the Turkish version (KMO = 0.82 and Chi-square P = 0.409), and the factor structure was similar to the original. The factors of the instrument were evaluated as consistent (Cronbach's alpha >0.60), and an overall Cronbach's alpha of 0.8485 was calculated. Conclusions: The Mig-SCog showed sufficient validity and reliability to be used in Turkish society.