Multisystemic inflammatory syndrome (Mis-C) has emerged in May 2020 as a serious complication of coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). A total of 6 children presented to tertiary care hospitals with Mis-C, of which 5 (83%) have died during hospitalization. All included patients presented with respiratory symptoms (ranged from mild to severe acute respiratory distress syndrome) and gastrointestinal symptoms. Most of the patients are known to have medical illnesses. Pediatric Risk of Mortality (PRISM) IV score ranged from 3 to 87. All patients developed acidosis and varying stages of acute kidney injury and electrolyte disturbances. All were treated for coagulopathy, thrombocytopenia, bacterial infections as well as antiviral medications (either ritonavir or lopinavir). Most patients had chest X-ray changes either unilateral or bilateral lung changes. Multisystemic inflammatory syndrome is a rare, yet serious complication of SARS-CoV2 infection in children. Multisystem involvement should be anticipated and promptly treated.

The present study aimed to evaluate the effectiveness of two doses of CoronaVac in preventing SARS-CoV-2 symptomatic disease with virological confirmation, as well as in the prevention of COVID-19 moderate and severe cases. A test-negative unmatched case-control design was used, in which cases were patients with suspected COVID-19 (presenting at least two of the following symptoms: fever, chills, sore throat, headache, cough, runny nose, olfactory or taste disorders) with virological confirmation, and controls were those whose SARS-CoV-2 test was negative. As for exposure, participants were classified as unvaccinated, or vaccinated with a complete schedule. Suspected COVID-19 cases were identified from March to November 2021, in two cities located in the State of São Paulo, Brazil. All participants signed the Informed Consent Form before enrollment. RT-PCR results and vaccination data were obtained from the local surveillance systems. Up to two phone calls were made to obtain information on the outcome of the cases. A total of 2981 potential participants were screened for eligibility, of which 2163 were included, being 493 cases and 1670 controls. Vaccination, age, the reported contact with a COVID-19 suspected or confirmed case in the 14 days before symptoms onset, and the educational level were the variables independently associated with the outcome. The adjusted vaccine effectiveness for symptomatic COVID-19 (AVE) was 39.0 % (95 % CI 6.0-60.0 %). The AVE in the prevention of moderate and severe disease was 91.0 % (95 % CI 76.0-97.0 %). Our results were influenced by the waning of the Gamma variant, in the second trimester of 2021, followed by the increase in vaccination coverage, and a drop in the number of cases in the second half of the year. The study demonstrated the high effectiveness of CoronaVac in preventing moderate/severe COVID-19 cases.

UNASSIGNED: Coinfection poses a persistent threat to global public health due to its severe effect on individual-level infection risk and disease outcome. Coinfection of SARS-CoV2 with one or more pathogens has been documented. Nevertheless, this virus co-infected with the Hantaan virus (HTNV) is rarely reported.
UNASSIGNED: Here, we presented three cases of HTNV complicated with SARS-CoV2 infection. Not only the conditions including general clinical manifestations, immune and inflammation parameters fluctuation presented in the single infection of HTNV or SARS-CoV2 can be found, but also the unexpected manifestations have attracted our attention that presented as more symptoms of HTNV infection including exudative changes in both lungs and an amount of bilateral pleural effusion as well as bilateral kidney enlargement rather than typical viral pneumonia in SARS-CoV2 infection. Fortunately, the conditions of patients gradually return to normal which is beneficial from the antiviral treatment, hemodialysis, and various supportive therapies including anti-inflammation, liver and gastric mucosa protection.
UNASSIGNED: Unexpected manifestations of coinfection patients present herein may be associated with multiple factors including virus load, competition or antagonism among antigens, and the susceptibility of target cells to the various pathogens, even though the pathogenesis of HTNV and SARS-CoV2 remains to be elucidated. Given that these two viruses have posed a profound influence on the socioeconomic, healthcare system worldwide, and the threat of coinfection to public health, it is warranted for clinicians, public health authorities, and infectious disease researchers to have a high index of consideration for patients co-infected with HTNV and SARS-CoV2.

UNASSIGNED: Antibodies against N-methyl-D-aspartate receptors are the most commonly identified cause of autoimmune encephalitis. While predominantly associated with malignancies, cases of anti-N-methyl-D-aspartate receptor autoimmune encephalitis have been reported after infections with the herpes-simplex virus or, more recently, in patients with severe COVID-19 disease.
UNASSIGNED: A previously healthy 17-year-old male adolescent acutely developed psychosis with auditory and visual hallucinations, fluctuating mental status, and an isolated seizure 5 weeks after a mildly symptomatic COVID-19 infection. The symptoms continued to worsen, accompanied by catatonia, and additional neurological symptoms developed during the initial antipsychotic treatment. A diagnostic workup revealed antibodies against N-methyl-D-aspartate receptors in the cerebrospinal fluid without other major abnormalities. After establishing the diagnosis, initiation of immunomodulatory therapy stopped the symptom progression and led to full recovery within 2 months.
UNASSIGNED: The case is remarkable in that anti-N-methyl-D-aspartate receptor autoimmune encephalitis developed shortly after a COVID-19 infection in an adolescent, despite the individual experiencing only mild COVID symptoms. The diagnosis should be considered in cases of acute-onset psychotic symptoms during or after COVID-19 infection, particularly in individuals without a prior psychiatric history, who present with atypical psychiatric or neurological features.

BACKGROUND: Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) responsible for coronavirus disease 2019 (COVID-19) is most well-known for causing pulmonary injury, a significant proportion of patients experience hepatic dysfunction. The mechanism by which SARS-CoV2 causes liver injury is not fully understood. The goal of this study was to describe the hepatic pathology in a large cohort of deceased patients with COVID-19 as compared to a control group of deceased patients without COVID-19.
METHODS: Consented autopsy cases at two institutions were searched for documentation of COVID-19 as a contributing cause of death. A group of consecutive consented autopsy cases during the same period, negative for SARS-CoV-2 infection, was used as a control group. The autopsy report and electronic medical records were reviewed for relevant clinicopathologic information. H&E-stained liver sections from both groups were examined for pertinent histologic features. Select cases underwent immunohistochemical staining for CD 68 and ACE2 and droplet digital polymerase chain reaction (ddPCR) assay for evaluation of SARS-CoV2 RNA.
RESULTS: 48 COVID-19 positive patients (median age 73, M:F 3:1) and 40 COVID-19 negative control patients (median age 67.5, M:F 1.4:1) were included in the study. The COVID-19 positive group was significantly older and had a lower rate of alcoholism and malignancy, but there was no difference in other comorbidities. The COVID-19 positive group was more likely to have received steroids (75.6 % vs. 36.1 %, p < 0.001). Hepatic vascular changes were seen in a minority (10.6 %) of COVID-19 positive cases. When all patients were included, there were no significant histopathologic differences between groups, but when patients with chronic alcoholism were excluded, the COVID-19 positive group was significantly more likely to have steatosis (80.9 % vs. 50.0 %, p = 0.004) and lobular inflammation (45.7 % vs. 20.7 %, p = 0.03). Testing for viral RNA by ddPCR identified 2 of the 18 (11.1 %) COVID-19 positive cases to have SARS-CoV-2 RNA detected within the liver FFPE tissue.
CONCLUSIONS: The most significant findings in the liver of COVID-19 positive patients were mild lobular inflammation and steatosis. The high rate of steroid therapy in this population may be a possible source of steatosis. Hepatic vascular alterations were only identified in a minority of patients and did not appear to play a predominant role in COVID-19 mediated hepatic injury. Low incidence of SARS-CoV-2 RNA positivity in liver tissue in our cohort suggests hepatic injury in the setting of COVID-19 may be secondary in nature.

Recent pharmacovigilance studies suggested that cluster headache could be a potential adverse effect after coronavirus disease-2019 (COVID-19) vaccination; however, the possibility of coincidence could not be excluded. Detailed case studies might help elucidate their potential link and implicate potential pathogenic mechanisms.
Patients who developed cluster headache in close temporal relationship to COVID-19 vaccination were identified from two tertiary medical centers in Japan and Taiwan respectively through 2021-2022. Detailed characteristics of the headaches and time between the onset of the index cluster episode and antecedent COVID-19 vaccination were reported. In patients with previous cluster headaches, the duration from previous bout was also recorded.
Six patients with new cluster headache bout 3-17 days after COVID-19 vaccination were identified. Two of them were de novo cases. The others either had been attack-free for a long time or developed new cluster bout in seasons atypical to prior bouts. The vaccines included mRNA, viral vector, or protein subunit vaccines.
COVID-19 vaccines, regardless of vaccine types, may elicit de novo or relapse of cluster headache. Future studies are needed to confirm the potential causality and explore the potential pathogenic mechanism.

During the SARS-CoV2 pandemic, several cases of Posterior Reversible Encephalopathy Syndrome (PRES) and of Reversible Cerebral Vasoconstriction Syndrome (RCVS) in COVID-19 patients have been reported, but the link between these syndromes and COVID-19 is unclear. We performed a systematic review, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to evaluate whether SARS-CoV2 infection or the drugs used to treat it could be deemed potential risk factors for PRES or RCVS. We performed a literature search. We found 70 articles (60 on PRES and 10 on RCVS) concerning n = 105 patients (n = 85 with PRES, n = 20 with RCVS). We analyzed the clinical characteristics of the two populations separately, then performed an inferential analysis to search for other independent risk factors. We found fewer than usual PRES-related (43.9%) and RCVS-related (45%) risk factors in patients with COVID-19. Such a low incidence of risk factors for PRES and RCVS might suggest the involvement of COVID-19 as an additional risk factor for both diseases due to its capability to cause endothelial dysfunction. We discuss the putative mechanisms of endothelial damage by SARS-CoV2 and antiviral drugs which may underlie the development of PRES and RCVS.

Miller Fisher Syndrome (MFS) was first recognized by James Collier in 1932 as a clinical triad of ataxia, areflexia, and ophthalmoplegia. In 1956, three cases with this triad were published by Charles Miller Fisher as a limited variant of Guillian-Barré syndrome (GBS), and the disease started to be called by his name. Since the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, there have been many reports of peripheral and central nervous system involvement. Until December 2022, a total of 23 cases including two children associated with MFS had been reported. In this article, we present a case of SARS-CoV-2 with classic triad clinical findings, which started with the atypical clinic at an early age. Electrophysiological studies of the case were found to be consistent with sensory axonal polyneuropathy. AntiGQ1b antibody IgG and IgM were negative. The case was spontaneously remitted without IV immunoglobulin (IVIg) or plasma exchange (PE) treatment. A current review of the literature is presented with the smallest pediatric case reported. Based on this case, it was planned to emphasize the targets and highlights in the diagnostic parameters.

Acute epiploic appendagitis is an uncommon cause of abdominal pain resulting from appendageal ischemia caused by torsion or thrombosis of the draining vein. It is frequently misdiagnosed as acute appendicitis or diverticulitis. The coronavirus disease 2019 (COVID-19) pandemic has changed how this rare disease is diagnosed. There was a report of a young men diagnosed with COVID-19 and epiploic appendagitis as a rare cause of abdominal pain. In addition, a 50-year-old men was diagnosed with epiploic appendagitis during the treatment of COVID-19. This paper reports the case of a 53-year-old men who presented with right lower quadrant abdominal pain after COVID-19 and was diagnosed with acute epiploic appendagitis by computed tomography image findings. The thrombotic condition of COVID-19 may contribute to acute appendagitis, but more studies are needed to confirm this hypothesis.

UNASSIGNED: Multisystem inflammatory syndrome in children (MIS-C), also known as pediatric inflammatory, multisystem syndrome temporally associated with SARS-CoV-2, is a rare but serious complication of SARS-CoV-2 infection in children that typically occurs 2-6 weeks after SARS-CoV-2 infection. The pathophysiology of MIS-C is unknown. MIS-C, first recognized in April 2020, is characterized by fever, systemic inflammation, and multi-system organ involvement. Post-vaccination adverse effects have increased with COVID-19 vaccinations, and MIS linked to immunization with COVID-19 vaccines has also been observed.
UNASSIGNED: An 11-year-old Chinese girl presented with a high-grade fever, rash, and dry cough for 2 days. She had her 2nd SARS-CoV-2 inactivated vaccination dose five days before hospital admission. On day 3 & 4, she experienced bilateral conjunctivitis, hypotension (66/47 mmHg), and a high CRP level. She was diagnosed with MIS-C. The patient\'s condition deteriorated rapidly, necessitating intensive care unit admission. The patient\'s symptoms improved after intravenous immunoglobulin, methylprednisolone, and oral aspirin therapy. She was discharged from the hospital after 16 days as her general condition, and laboratory biomarkers returned to normal.
UNASSIGNED: Inactivated Covid-19 vaccination might trigger MIS-C. Further research is needed to evaluate whether a correlation exists between COVID-19 vaccination and MIS-C development.