Symptoms, complications and management of long COVID: a review.

Globally, there are now over 160 million confirmed cases of COVID-19 and more than 3 million deaths. While the majority of infected individuals recover, a significant proportion continue to experience symptoms and complications after their acute illness. Patients with 'long COVID' experience a wide range of physical and mental/psychological symptoms. Pooled prevalence data showed the 10 most prevalent reported symptoms were fatigue, shortness of breath, muscle pain, joint pain, headache, cough, chest pain, altered smell, altered taste and diarrhoea. Other common symptoms were cognitive impairment, memory loss, anxiety and sleep disorders. Beyond symptoms and complications, people with long COVID often reported impaired quality of life, mental health and employment issues. These individuals may require multidisciplinary care involving the long-term monitoring of symptoms, to identify potential complications, physical rehabilitation, mental health and social services support. Resilient healthcare systems are needed to ensure efficient and effective responses to future health challenges.

The Intersection of Parkinson's Disease, Viral Infections, and COVID-19.

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the causative agent of human COVID-19, not only causes flu-like symptoms and gut microbiome complications but a large number of infected individuals also experience a host of neurological symptoms including loss of smell and taste, seizures, difficulty concentrating, decreased alertness, and brain inflammation. Although SARS-CoV-2 infections are not more prevalent in Parkinson's disease patients, a higher mortality rate has been reported not only associated with older age and longer disease duration, but also through several mechanisms, such as interactions with the brain dopaminergic system and through systemic inflammatory responses. Indeed, a number of the neurological symptoms seen in COVID-19 patients, as well as the alterations in the gut microbiome, are also prevalent in patients with Parkinson's disease. Furthermore, biochemical pathways such as oxidative stress, inflammation, and protein aggregation have shared commonalities between Parkinson's disease and COVID-19 disease progression. In this review, we describe and compare the numerous similarities and intersections between neurodegeneration in Parkinson's disease and RNA viral infections, emphasizing the current SARS-CoV-2 global health crisis.

Chemosensory Systems in COVID-19: Evolution of Scientific Research.

COVID-19 disease induced by coronavirus SARS-CoV-2 presents among its symptoms alterations of the chemosensory functions. In the first studies on the Chinese population, this symptomatology was not particularly relevant, and hyposmia and hypogeusia were excluded from the symptoms to be evaluated to diagnose the disease. With the pandemic spread of the illness, there has been an augment in reports on chemosensory dysfunctions among patients. The first data analysis showed the presence of these disorders mainly in paucisymptomatic and asymptomatic patients. The interest in chemosensory systems therefore increased considerably, because the olfactory and gustatory symptoms could be the key to stop the infection spread. Furthermore, the degree of alert and attention grew, considering that these types of dysfunctions are prognostic symptoms of serious neurodegenerative diseases. About 9 months have passed since the first anecdotal reports on the involvement of the olfactory and gustatory systems in the COVID-19 pathology. For this reason, a careful review of the literature was conducted to understand if it is clearer which people present chemosensory symptoms and if these are related to the severity of the disease. Furthermore, we have identified which aspects still remain to be clarified.

Posterior circulation stroke presenting as a new continuous cough: not always COVID-19.

A 19-year-old man was admitted with a 2-week history of continuous cough along with a day history of acute onset unsteadiness and hiccups. Given the current pandemic, he was initially suspected to have COVID-19, however he tested negative on two occasions. Subsequent brain magnetic resonance imaging (MRI)confirmed a small left acute and subacute lateral medullary infarction with chest X-ray suggesting aspiration pneumonia with right lower lobe collapse. This is a distinctive case of posterior circulation stroke presenting with a new continuous cough in this era of COVID-19 pandemic. We anticipate based on MRI findings that his persistent cough was likely due to silent aspiration from dysphagia because of the subacute medullary infarction. It is therefore imperative that healthcare workers evaluate people who present with new continuous cough thoroughly to exclude any other sinister pathology. We should also be familiar with the possible presentations of posterior circulation stroke in this pandemic era.

Widespread sensory neuropathy in diabetic patients hospitalized with severe COVID-19 infection.

AIMS: To characterize the distribution and severity of sensory neuropathy using a portable quantitative sensory testing (QST) device in diabetic patients (DM) hospitalized with severe COVID-19 infection. METHODS: Four patients with diabetes and severe SARS-CoV-2 requiring non-invasive ventilation for a protracted duration underwent clinical, laboratory and radiologic assessment and detailed evaluation of neuropathic symptoms, neurological assessment, QST on the dorsum of the foot and face using NerveCheck Master with assessment of taste and smell. RESULTS: All four subjects developed neuropathic symptoms characterized by numbness in the feet with preserved reflexes. QST confirmed symmetrical abnormality of vibration and thermal thresholds in both lower limbs in all patients and an abnormal heat pain threshold on the face of two patients and altered taste and smell. CONCLUSIONS: Severe COVID-19 infection with hypoxemia is associated with neuropathic symptoms and widespread sensory dysfunction in patients with DM.

Effects of the severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV) on the nervous system. What can we expect from SARS -CoV-2? / [Efectos de los coronavirus del síndrome respiratorio agudo grave (SARS-CoV) y del síndrome respiratorio del Medio Oriente (MERS-CoV) en el sistema nervioso. ¿Qué esperar del SARS-CoV-2?]

Coronaviruses cause respiratory and gastrointestinal disorders in animals and humans. The current SARS-CoV-2, the COVID-19 infectious agent, belongs to a subgroup called betacoronavirus including the SARS-CoV and MERS-CoV responsible for epidemics in 2002 and 2012, respectively. These viruses can also infect the nervous system due to their affinity for the human angiotensin-converting enzyme 2 (ACE2) expressed in neurons and glial cells. Infections with SARS-CoV, MERS-CoV, and now SARS-CoV-2 also produce neurological signs such as acute cerebrovascular disease, impaired consciousness, and muscle injury, as well as dizziness, hypogeusia, hyposmia, hypoxia, neuralgia, and hypoxic encephalopathy. For this reason, close attention should be paid to the neurological manifestations of COVID-19 patients.

Los coronavirus son una familia de virus que se caracterizan por producir afectaciones respiratorias y gastrointestinales en animales y en seres humanos. El actual SARS-CoV-2, agente infeccioso de la COVID-19, pertenece a un subgrupo denominado betacoronavirus del que hacen parte el SARS-CoV y MERS-CoV, virus responsables de epidemias en el 2002 y el 2012, respectivamente. Estos virus también pueden infectar el sistema nervioso debido a su afinidad con la enzima convertidora de angiotensina humana 2 (ACE2), la cual se expresa en neuronas y células gliales. Se ha demostrado que las infecciones con SARS-CoV y MERS-CoV, y ahora también con el SARS-CoV-2, ocasionan condiciones neurológicas como la enfermedad cerebrovascular aguda, la conciencia alterada y las lesiones musculares, así como mareos, hipogeusia, hiposmia, hipoxia, neuralgia y encefalopatía hipóxica. Por ello debe prestarse mucha atención a las manifestaciones neurológicas de los pacientes de COVID-19.

Case Series of Headache Characteristics in COVID-19: Headache Can Be an Isolated Symptom.

Headache was reported in up to one-third of the hospitalized patients; yet, the clinical characteristics of headache associated with coronavirus disease 2019 (COVID-19) have not been defined. This observational case study included patients who were consulted to headache unit due to headache and had COVID-19 illness. Headache features in 13 PCR-confirmed COVID-19 patients with mild symptoms were reported. Headache was the isolated symptom of the COVID-19 in 3 patients and emerged as an early symptom during the disease course in all patients. Patients specified severe, rapid onset, unrelenting headache with migraine-like features, as well as unusual sensory symptoms such as anosmia, and gastrointestinal symptoms such as diarrhea and loss of appetite and weight. Headache lasted up to 3 days in 70% of the patients and resolved in all patients within 2 weeks. Despite the fact that most of the patients were female and headache characteristics were suggestive of migraine, majority of patients were not suffering from primary headaches. It was concluded that headache could be an isolated symptom of COVID-19, which might possibly be ignored in asymptomatic patients. Headaches associated with COVID-19 included features resembling migraine and/or atypical symptoms including anosmia and diarrhea.

Spectrum of Headaches Associated With SARS-CoV-2 Infection: Study of Healthcare Professionals.

BACKGROUND: Series of patients with SARS-CoV-2 infection report headache in 6%-15% of cases, although some data suggest that the actual frequency is higher, and that headache is not associated with fever. No study published to date has analyzed the characteristics of headache in these patients. OBJECTIVE: To analyze the characteristics of COVID-19 related headaches. METHODS: We conducted a survey of Spaniard healthcare professionals who have been infected by SARS-CoV-2 and presented headache during the course of the disease. The survey addressed respondents' medical history and headache characteristics, and we analyzed the association between both. RESULTS: We analyzed the responses of a sample of 112 healthcare professionals. History of migraine was reported by 20/112 (17.9%) of respondents, history of tension-type headache by 8/112 (7.1%), and history of cluster headache was reported by a single respondent; 82/112(73.2%) of respondents had no history of headache. Headache presented independently of fever, around the third day after symptom onset. The previous history of migraine was associated with a higher frequency of pulsating headache (20% in patients with previous migraine vs 4.3% in those with no history of migraine, P = .013). CONCLUSION: Headache is often holocranial, hemicranial, or occipital, pressing, and worsens with physical activity or head movements. Because the characteristics of the headache and the associated symptoms are heterogeneous in our survey, we suggest that several patterns with specific pathophysiological mechanisms may underlie the headache associated with COVID-19.

AhR and IDO1 in pathogenesis of Covid-19 and the "Systemic AhR Activation Syndrome:" a translational review and therapeutic perspectives.

Covid-19 is the acute illness caused by SARS-CoV-2 with initial clinical symptoms such as cough, fever, malaise, headache, and anosmia. After entry into cells, corona viruses (CoV) activate aryl hydrocarbon receptors (AhRs) by an indoleamine 2,3-dioxygenase (IDO1)-independent mechanism, bypassing the IDO1-kynurenine-AhR pathway. The IDO1-kynurenine-AhR signaling pathway is used by multiple viral, microbial and parasitic pathogens to activate AhRs and to establish infections. AhRs enhance their own activity through an IDO1-AhR-IDO1 positive feedback loop prolonging activation induced by pathogens. Direct activation of AhRs by CoV induces immediate and simultaneous up-regulation of diverse AhR-dependent downstream effectors, and this, in turn, results in a "Systemic AhR Activation Syndrome" (SAAS) consisting of inflammation, thromboembolism, and fibrosis, culminating in multiple organ injuries, and death. Activation of AhRs by CoV may lead to diverse sets of phenotypic disease pictures depending on time after infection, overall state of health, hormonal balance, age, gender, comorbidities, but also diet and environmental factors modulating AhRs. We hypothesize that elimination of factors known to up-regulate AhRs, or implementation of measures known to down-regulate AhRs, should decrease severity of infection. Although therapies selectively down-regulating both AhR and IDO1 are currently lacking, medications in clinical use such as dexamethasone may down-regulate both AhR and IDO1 genes, as calcitriol/vitamin D3 may down-regulate the AhR gene, and tocopherol/vitamin E may down-regulate the IDO1 gene. Supplementation of calcitriol should therefore be subjected to epidemiological studies and tested in prospective trials for prevention of CoV infections, as should tocopherol, whereas dexamethasone could be tried in interventional trials. Because lack of physical exercise activates AhRs via the IDO1-kynurenine-AhR signaling pathway increasing risk of infection, physical exercise should be encouraged during quarantines and stay-at-home orders during pandemic outbreaks. Understanding which factors affect gene expression of both AhR and IDO1 may help in designing therapies to prevent and treat humans suffering from Covid-19.

Involvement of the Nervous System in SARS-CoV-2 Infection.

As a severe and highly contagious infectious disease, coronavirus disease 2019 (COVID-19) has caused a global pandemic. Several case reports have demonstrated that the respiratory system is the main target in patients with COVID-19, but the disease is not limited to the respiratory system. Case analysis indicated that the nervous system can be invaded by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and that 36.4% of COVID-19 patients had neurological symptoms. Importantly, the involvement of the CNS may be associated with poor prognosis and disease worsening. Here, we discussed the symptoms and evidence of nervous system involvement (directly and indirectly) caused by SARS-CoV-2 infection and possible mechanisms. CNS symptoms could be a potential indicator of poor prognosis; therefore, the prevention and treatment of CNS symptoms are also crucial for the recovery of COVID-19 patients.