(1) Background: Reversible cerebral vasoconstriction syndrome (RCVS) encompasses a clinical and radiological diagnosis characterized by recurrent thunderclap headache, with or without focal deficits due to multifocal arterial vasoconstriction and dilation. RCVS can be correlated to pregnancy and exposure to certain drugs. Currently, the data on prevalence of RCVS in the postpartum period is lacking. We aim to investigate the prevalence of RCVS in the postpartum period and the rate of hemorrhagic complications of RCVS among the same group of patients; (2) Methods: We conducted the metanalysis by using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and Meta-Analyses and Systematic Reviews of Observational Studies in Epidemiology (MOOSE) protocol. To analyze the Bias, we used the Ottawa Newcastle scale tool. We included only full-text observational studies conducted on humans and written in English. We excluded Literature Reviews, Systematic Reviews, and Metanalysis. Additionally, we excluded articles that did not document the prevalence of RCVS in the postpartum period (3). Results: According to our analysis, the Prevalence of RCVS in the postpartum period was 129/1083 (11.9%). Of these, 51/100 (52.7%) patients had hemorrhagic RCVS vs. 49/101 (49.5%) with non-hemorrhagic RCVS. The rates of Intracerebral Hemorrhage (ICH) and Subarachnoid Hemorrhage (SAH) were (51.6% and 10.7%, respectively. ICH seems to be more common than.; (4) Conclusions: Among patients with RCVS, the prevalence in PP patients is relativity high. Pregnant women with RCVS have a higher recurrence of hemorrhagic vs. non-hemorrhagic RCVS. Regarding the type of Hemorrhagic RCVS, ICH is more common than SAH among patients in the postpartum period. Female Sex, history of migraine, and older age group (above 45) seem to be risk factors for H-RCVS. Furthermore, recurrence of RCVS is associated with a higher age group (above 45). Recurrence of RCVS is more commonly idiopathic than being triggered by vasoactive drugs in the postpartum period.

Mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a mitochondrial disease that lacks a definitive treatment. Lately, there has been an increased interest in the scientific community about the role of arginine in the short and long-term settings of the disease. We aim to conduct a systematic review of the clinical use of arginine in the management of MELAS and explore the role of arginine in the pathophysiology of the disease. We used PubMed advanced-strategy searches and only included full-text clinical trials on humans written in the English language. After applying the inclusion/exclusion criteria, four clinical trials were reviewed. We used the Meta-analysis of Observational Studies in Epidemiology (MOOSE) guidelines and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol for this systematic review. We used the Cochrane Collaboration risk-of-bias tool to assess the bias encountered in each study. Overall, IV arginine seems to be effective in improving symptoms during acute attacks of MELAS, while oral arginine supplementation increases endothelial function, preventing further stroke-like episodes.

Kleine–Levin syndrome (KLS) is characterized by episodes of hypersomnia. Additionally, these patients can present with hyperphagia, hypersexuality, abnormal behavior, and cognitive dysfunction. Functional neuroimaging studies such as fMRI-BOLD, Positron Emission Tomography (PET) or SPECT help us understand the neuropathological bases of different disorders. We conducted a systematic review to investigate the neuroimaging features of KLS patients and their clinical correlations. This systematic review was conducted by following the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) and PRISMA protocol reporting guidelines. We aim to investigate the clinical correlation with neuroimaging among patients with KLS. We included only studies written in the English language in the last 20 years, conducted on humans; 10 studies were included. We excluded systematic reviews, metanalysis, and case reports. We found that there are changes in functional imaging studies during the symptomatic and asymptomatic periods as well as in between episodes in patients with K.L.S. The areas most reported as affected were the hypothalamic and thalamic regions, which showed hypoperfusion and, in a few cases, hyperperfusion; areas such as the frontal, parietal, occipital and the prefrontal cortex all showed alterations in cerebral perfusion. These changes in cerebral blood flow and regions vary according to the imaging (SPECT, PET SCAN, or fMRI) and the task performed while imaging was performed. We encountered conflicting data between studies. Hyper insomnia, the main feature of this disease during the symptomatic periods, was associated with decreased thalamic activity. Other features of K.L.S., such as apathy, hypersexuality, and depersonalization, were also correlated with functional imaging changes. There were also findings that correlated with working memory deficits seen in this stage during the asymptomatic periods. Hyperactivity of the thalamus and hypothalamus were the main features shown during the asymptomatic period. Additionally, functional imaging tends to improve with a longer course of the disease, which suggests that K.L.S. patients outgrow the disease. These findings should caution physicians when analyzing and correlating neuroimaging findings with the disease.

PCDH19 syndrome is a monogenic epilepsy related to the protein protocadherin-19 (PCDH19) gene, which encodes for a protein important for brain development. The protein also seems to regulate gamma-aminobutyric acid type A receptors (GABA(A)(R)). The disease presents with refractory epilepsy that is characterized by seizures occurring in clusters. Till now, the pathophysiology of the disease is mainly unknown, so we conducted a literature review to elucidate the pathophysiology of PCDH19-related epilepsy. We used two databases to investigate this literature review (Google Scholar and PubMed). We selected full-text papers that are published in the English language and published after the year 2000. We selected initially 64 papers and ended up with 29 to conduct this literature review. We found four main theories for the pathophysiology of PCDH19-related epilepsy: GABA(A)(R) dysregulation, blood-brain barrier (BBB) dysfunction, cellular interference, and the AKR1C1-3 gene product deficiency. GABA(A)(R) dysfunction and expression cause decreased effective inhibitory currents predisposing patients to epilepsy. BBB dysfunction allows the passage of methyl-D-aspartate (NMDA)-type glutamate receptor antibodies (abs-NR) through the BBB susceptible membrane. The cellular interference hypothesis establishes that the mutant and non-mutant cells interfere with each other’s communication within the same tissue. Women are more susceptible to being affected by this hypothesis as men only have one copy of the x gene and interference is mediated by this gene, meaning that it cannot occur in them. Finally, downregulation and deficiency of the AKR1C3/AKR1C2 products lead to decreasing levels of allopregnanolone, which diminish the regulation of GABA(A)(R).

Ataxia is a constellation of symptoms that involves a lack of coordination, imbalance, and difficulty walking. Hereditary ataxia occurs when a person is born with defective genes, and this degenerative disorder may progress for several years. There is no effective cure for ataxia, so we need to search for new treatments. Recently, interest in riluzole in the treatment of ataxia has emerged. We conducted this systematic review to analyze the safety and efficacy of riluzole for treating hereditary ataxia in recent clinical trials. We conducted a systematic review using PubMed and Google Scholar as databases in search of this relationship. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) protocols to conduct this study. For inclusion criteria, we included full-text clinical trials on humans written in English and found three clinical trials. We excluded case reports, literature reviews, systematic reviews, and meta-analyses for this analysis. We aimed to evaluate the Scale for the Assessment and Rating of Ataxia (SARA) score, the International Cooperative Ataxia Rating Scale (ICARS) score, and the safety of the medication. Two out of the three clinical trials showed statistically significant clinical improvement in the ICARS and SARA scores, while the other trial did not show improvement in the clinical or radiological outcomes. The drug was safe in all clinical trials. Overall, the results of this analysis of riluzole for the treatment of hereditary ataxia are encouraging. Further clinical trials are needed to investigate the efficacy of riluzole on hereditary ataxia.

Stroke is a leading cause of death and disability, especially in certain ethnic groups. Impaired consciousness is a common outcome in stroke patients, serving as a predictor of prognosis and mortality. Lately, there has been increased interest in drugs such as Levodopa (LD), which have been found to promote wakefulness. To further appreciate this association, we gathered updated evidence of this novel therapeutic approach and compared it, evaluating its clinical use in an acute stroke setting. We carried out a systematic review of clinical trials conducted exclusively on stroke patients who received levodopa. Four clinical trials were reviewed and analyzed after applying the inclusion/exclusion criteria. The use of levodopa showed positive results in four of the clinical trials, and statistically significant results in 3/4 of the studies; however, more studies need to be conducted to corroborate these results.