Brain autopsies of critically ill COVID-19 patients demonstrate heterogeneous profile of acute vascular injury, inflammation and age-linked chronic brain diseases

Abstract:

Background: This study examined neuropathological findings of patients who died following hospitalization in an intensive care unit with SARS-CoV-2.

Methods: Data originate from 20 decedents who underwent brain autopsy followed by ex-vivo imaging and dissection. Systematic neuropathologic examinations were performed to assess histopathologic changes including cerebrovascular disease and tissue injury, neurodegenerative diseases, and inflammatory response. Cerebrospinal fluid (CSF) and fixed tissues were evaluated for the presence of viral RNA and protein.

Results: The mean age-at-death was 66.2 years (range: 26-97 years) and 14 were male. The patient’s medical history included cardiovascular risk factors or diseases (n = 11, 55%) and dementia (n = 5, 25%). Brain examination revealed a range of acute and chronic pathologies. Acute vascular pathologic changes were common in 16 (80%) subjects and included infarctions (n = 11, 55%) followed by acute hypoxic/ischemic injury (n = 9, 45%) and hemorrhages (n = 7, 35%). These acute pathologic changes were identified in both younger and older groups and those with and without vascular risk factors or diseases. Moderate-to-severe microglial activation were noted in 16 (80%) brains, while moderate-to-severe T lymphocyte accumulation was present in 5 (25%) brains. Encephalitis-like changes included lymphocytic cuffing (n = 6, 30%) and neuronophagia or microglial nodule (most prominent in the brainstem, n = 6, 30%) were also observed. A single brain showed vasculitis-like changes and one other exhibited foci of necrosis with ball-ring hemorrhages reminiscent of acute hemorrhagic leukoencephalopathy changes. Chronic pathologies were identified in only older decedents: 7 brains exhibited neurodegenerative diseases and 8 brains showed vascular disease pathologies. CSF and brain samples did not show evidence of viral RNA or protein.

Conclusions: Acute tissue injuries and microglial activation were the most common abnormalities in COVID-19 brains. Focal evidence of encephalitis-like changes was noted despite the lack of detectable virus. The majority of older subjects showed age-related brain pathologies even in the absence of known neurologic disease. Findings of this study suggest that acute brain injury superimposed on common pre-existing brain disease may put older subjects at higher risk of post-COVID neurologic sequelae.

Source: Agrawal S, Farfel JM, Arfanakis K, Al-Harthi L, Shull T, Teppen TL, Evia AM, Patel MB, Ely EW, Leurgans SE, Bennett DA, Mehta R, Schneider JA. Brain autopsies of critically ill COVID-19 patients demonstrate heterogeneous profile of acute vascular injury, inflammation and age-linked chronic brain diseases. Acta Neuropathol Commun. 2022 Dec 17;10(1):186. doi: 10.1186/s40478-022-01493-7. PMID: 36528671; PMCID: PMC9758667. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9758667/ (Full text)

Clinical characteristics of patients with unexplainable hypothalamic disorder diagnosed by the corticotropin-releasing hormone challenge test: a retrospective study

Abstract

Background: The corticotropin-releasing hormone (CRH) challenge test can distinguish the disorders of the hypothalamus from those of the pituitary. However, the pathophysiology of hypothalamic disorder (HD) has not been fully understood. This study aimed to elucidate the clinical characteristics of patients with unexplainable HD, diagnosed by the CRH challenge test.

Methods: We retrospectively reviewed patients who underwent the CRH challenge test. Patients were categorized into four groups as follows: patients with peak serum cortisol ≥18 μg/dL were assigned to the normal response (NR) group (n = 18), among patients with peak serum cortisol < 18 μg/dL and peak adrenocorticotropic hormone (ACTH) increase ≥two-fold, patients without obvious background pathology were assigned to the unexplainable-HD group (n = 18), whereas patients with obvious background pathology were assigned to the explainable-HD group (n = 38), and patients with peak serum cortisol < 18 μg/dL and peak ACTH increase <two-fold were assigned to the pituitary disorder (PD) group (n = 15). Inter-group comparisons were performed based on clinical characteristics.

Results: In the CRH challenge test, the peak plasma ACTH levels were significantly lower in the unexplainable-HD group than in the NR group, despite more than two-fold increase compared to basal levels. The increase in serum cortisol was significantly higher in the unexplainable-HD group than in the explainable-HD and PD groups. Although patients in the unexplainable-HD group showed a clear ACTH response in the insulin tolerance test, some patients had peak serum cortisol levels of < 18 μg/dL. Furthermore, attenuated diurnal variations and low normal levels of urinary free cortisol were observed. Most patients in the unexplainable-HD group were young women with chronic fatigue. However, supplementation with oral hydrocortisone at physiological doses reduced fatigue only in some patients.

Conclusions: Patients with unexplainable HD diagnosed by the CRH challenge test had hypothalamic-pituitary-adrenal (HPA) axis dysfunction and some patients had mild central adrenal insufficiency. Hydrocortisone supplementation reduced fatigue only in some patients, suggesting that HPA axis dysfunction may be a physiological adaptation. Further investigation of these patients may help elucidate the pathophysiology of myalgic encephalitis/chronic fatigue syndrome.

Source: Hataya Y, Okubo M, Hakata T, Fujimoto K, Iwakura T, Matsuoka N. Clinical characteristics of patients with unexplainable hypothalamic disorder diagnosed by the corticotropin-releasing hormone challenge test: a retrospective study. BMC Endocr Disord. 2022 Dec 9;22(1):312. doi: 10.1186/s12902-022-01237-7. PMID: 36494805; PMCID: PMC9733005. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9733005/ (Full text)

Investigating the neural substrates of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) : a structural and functional MRI study

Abstract:

Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is characterised by continuous fatigue and has many diagnostic criteria. Cognitive dysfunction affects 86-94% of adults with CFS/ME.

This thesis used MRI applications to investigate brain structure and function in CFS/ME. This thesis hypothesised to find brain volume differences, functional connectivity differences in brain networks, and functional differences measured by Blood Oxygenation Level Dependant (BOLD) signal activation during working memory task performance.

The working memory paradigm was designed to investigate working memory components, processing and storage separately and combined. The relationship between fatigue and performance was assessed. This thesis’s original contribution provides evidence that the salience network might have altered resting-state functional connectivity in CFS/ME in the absence of morphological differences.

The salience network is involved in detecting and integrating salient sensory information; therefore, disruption in this network might disrupt incoming cognitive stimuli and influence other networks’ connectivity, involved in fatigue and impaired memory.

In the more demanding task, participants with CFS/ME were slower and less accurate but used the same working memory network as healthy controls. No brain volume differences, nor atrophy were found. The differences between these findings compared to previous studies might be due to different study designs, analysis methods, sample sizes with different symptoms, including illness duration, physical inactivity and sleep disturbance.

The salience network alteration could potentially have a significant role in CFS/ME, as we cannot determine cause and effect with current experimental design the association with fatigue and other CFS/ME symptoms remains unclear. Using longitudinal studies that account for neurologically relevant confounders are needed in CFS/ME to further investigate the role of salience network.

Source: Almutairi, Basim S. Investigating the neural substrates of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) : a structural and functional MRI study. PhD Thesis, University of Bristol. uk.bl.ethos.866683  https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.866683

What Causes ME/CFS: The Role of the Dysfunctional Immune System and Viral Infections

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) remains an enigmatic highly disabling and complex long-term condition with a wide range of aetiologies and symptoms.

A viral onset is commonly mentioned by patients and several bodily systems are ultimately disturbed. The parallel with long-covid is clear.

However, immune dysregulation with impaired NK cell dysfunction and tendency to novel autoimmunity have been frequently reported. These may contribute to reactivation of previous acquired viruses/retroviruses accompanied by impaired endocrine regulation and mitochondrial energy generation.

The unpredictable nature of seemingly unconnected and diverse symptoms that are poorly responsive to several allopathic and alternative therapies then contributes to an escalation of the illness with secondary dysfunction of multiple other systems. Treatment of established ME/CFS is therefore difficult and requires multi-specialty input addressing each of the areas affected by the illness.

Source: Amolak S Bansal, Aletta D Kraneveld, Elisa Oltra and Simon Carding. What Causes ME/CFS: The Role of the Dysfunctional Immune System and Viral Infections. Journal of Immunology and Allergy 2022;3(2):1-15. https://maplespub.co.in/assets/images/files/doc_1663924267.pdf (Full text)

A comparison of health-related factors between patients diagnosed with ME/CFS and patients with a related symptom picture but no ME/CFS diagnosis: a cross-sectional exploratory study

Abstract:

Background: In chronic fatigue syndrome/myalgic encephalomyelitis (ME/CFS), the capacity for activity and participation is strongly limited. The disease definition is very broad, and considering the lack of evidence for best treatment, it is important to understand what is ME/CFS-specific in the biopsychosocial perspective in comparison with similar syndromes. The objective was to study the difference between those diagnosed with ME/CFS and those with similar symptoms but no ME/CFS diagnosis for self-perceived level of physical activity, work ability, anxiety/depression, and health-related quality of life.

Methods: This was a clinical cross-sectional study with data collected from mailed questionnaires. The following variables were compared between patients diagnosed with ME/CFS (n = 205) and those with similar symptoms but no diagnosis (n = 57); level of physical activity, Work ability index (WAI), Hospital anxiety and depression scale (HAD-A/HAD-D), and RAND-36 Physical functioning, Role limitations due to physical health problems, Role limitations due to personal or emotional problems, Social functioning, Energy/fatigue, Bodily pain, Emotional well-being, and General health perceptions. The Chi-squared test (nominal data), the Mann-Whitney U test, the Student’s t test and regression analysis were used to analyze the data.

Results: The group diagnosed with ME/CFS had a more impaired physical and mental exertion ability as compared to the group that had similar symptoms but was not diagnosed with ME/CFS, shown by a RAND-36 lower index of physical role functioning, social functioning, energy, worse pain and poorer overall health (p ≤ 0.05). In contrast, no significant group differences emerged for weekly level of physical activity, work ability, anxiety/depression, and RAND-36 Emotional role limitation and well-being.

Conclusion: Our results indicate that those with a diagnosis of ME/CFS are characterized by an impaired ability for physical or mental exertion, worse pain, and poorer overall health as compared to individuals with similar symptoms but for whom ME/CFS-diagnosis was not established. The results may be cautiously interpreted as support when focusing on patients’ self-care in terms of management of energy levels. The results must however be verified in future studies.

Source: Bernhoff G, Rasmussen-Barr E, Bunketorp Käll L. A comparison of health-related factors between patients diagnosed with ME/CFS and patients with a related symptom picture but no ME/CFS diagnosis: a cross-sectional exploratory study. J Transl Med. 2022 Dec 9;20(1):577. doi: 10.1186/s12967-022-03769-x. PMID: 36494693; PMCID: PMC9733040. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-022-03769-x (Full text)

ME/CFS and Post-Exertional Malaise among Patients with Long COVID

Abstract:

This study sought to ascertain the prevalence of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) among a sample of 465 patients with Long COVID. The participants completed three questionnaires: (1) a new questionnaire measuring both the frequency and severity of 38 common symptoms of COVID and Long COVID, (2) a validated short form questionnaire assessing ME/CFS, and (3) a validated questionnaire measuring post-exertional malaise.
The population was predominantly white, female, and living in North America. The mean duration since the onset of COVID-19 symptoms was 70.5 weeks. Among the 465 participants, 58% met a ME/CFS case definition. Of respondents who reported that they had ME/CFS only 70.57% met criteria for ME/CFS and of those who did not report they had ME/CFS, 29.43% nevertheless did meet criteria for the disease: both over-diagnosis and under-diagnosis were evident on self-report. This study supports prior findings that ME/CFS occurs with high prevalence among those who have persistent COVID-19 symptoms.
Source: Jason LA, Dorri JA. ME/CFS and Post-Exertional Malaise among Patients with Long COVID. Neurology International. 2023; 15(1):1-11. https://doi.org/10.3390/neurolint15010001 https://www.mdpi.com/2035-8377/15/1/1 (Full text)

Feasibility Assessment of a School Nurse-Led Approach Using Chronic Absenteeism to Establish the School-Based Active Surveillance Process

Abstract:

This article shares what was learned from the feasibility assessment of a nurse-led school-based active surveillance (SBAS) pilot to track chronic absenteeism using myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) as an exemplar. This pilot encompassed a 3-year period with training and feedback from school nurses (SNs) on data collection and ME/CFS. SNs found that the SBAS process helped them effectively identifying undiagnosed conditions.

The assessment revealed the importance of focusing outreach efforts and establishing relationships with the school leadership in developing health policies and programs in the school setting. The pilot data were used to develop a manual to guide SNs for the SBAS process. This can be viewed as a model for SNs in establishing a surveillance to identify and track conditions like ME/CFS. With overlapping symptoms of Long COVID to ME/CFS, this assessment may provide insights for additional efforts to understand the impact of Long COVID on students’ education.

Source: Maughan ED, Thompson ME, Walsh CA, Issa A, Lin JS. Feasibility Assessment of a School Nurse-Led Approach Using Chronic Absenteeism to Establish the School-Based Active Surveillance Process. J Sch Nurs. 2022 Dec 20:10598405221144259. doi: 10.1177/10598405221144259. Epub ahead of print. PMID: 36540020. https://pubmed.ncbi.nlm.nih.gov/36540020/

Selective inhibition of miRNA processing by a herpesvirus-encoded miRNA

Abstract:

Herpesviruses have mastered host cell modulation and immune evasion to augment productive infection, life-long latency and reactivation1,2. A long appreciated, yet undefined relationship exists between the lytic-latent switch and viral non-coding RNAs3,4. Here we identify viral microRNA (miRNA)-mediated inhibition of host miRNA processing as a cellular mechanism that human herpesvirus 6A (HHV-6A) exploits to disrupt mitochondrial architecture, evade intrinsic host defences and drive the switch from latent to lytic virus infection.

We demonstrate that virus-encoded miR-aU14 selectively inhibits the processing of multiple miR-30 family members by direct interaction with the respective primary (pri)-miRNA hairpin loops. Subsequent loss of miR-30 and activation of the miR-30-p53-DRP1 axis triggers a profound disruption of mitochondrial architecture. This impairs induction of type I interferons and is necessary for both productive infection and virus reactivation.

Ectopic expression of miR-aU14 triggered virus reactivation from latency, identifying viral miR-aU14 as a readily druggable master regulator of the herpesvirus lytic-latent switch. Our results show that miRNA-mediated inhibition of miRNA processing represents a generalized cellular mechanism that can be exploited to selectively target individual members of miRNA families. We anticipate that targeting miR-aU14 will provide new therapeutic options for preventing herpesvirus reactivations in HHV-6-associated disorders.

Source: Hennig T, Prusty AB, Kaufer BB, Whisnant AW, Lodha M, Enders A, Thomas J, Kasimir F, Grothey A, Klein T, Herb S, Jürges C, Sauer M, Fischer U, Rudel T, Meister G, Erhard F, Dölken L, Prusty BK. Selective inhibition of miRNA processing by a herpesvirus-encoded miRNA. Nature. 2022 May;605(7910):539-544. doi: 10.1038/s41586-022-04667-4. Epub 2022 May 4. PMID: 35508655.  https://pubmed.ncbi.nlm.nih.gov/35508655/

Post-Viral Fatigue Following SARS-CoV-2 Infection during Pregnancy: A Longitudinal Comparative Study

Abstract:

Studies reported post-COVID-19 fatigue in the general population, but not among pregnant women. Our objectives were to determine prevalence, duration, and risk factors of post-viral fatigue among pregnant women with SARS-CoV-2.

This study involved 588 pregnant women with SARS-CoV-2 during pregnancy or delivery in Brazil. Three groups were investigated: G1 (n = 259, symptomatic infection during pregnancy); G2 (n = 131, positive serology at delivery); G3 (n = 198, negative serology at delivery). We applied questionnaires investigating fatigue at determined timepoints after infection for G1, and after delivery for all groups; fatigue prevalence was then determined.

Cox regression was used to estimate hazard ratio (HR) and 95% CI of the risk of remaining with fatigue in G1. Overall fatigue prevalence in G1 at six weeks, three months and six months were 40.6%, 33.6%, and 27.8%, respectively. Cumulative risk of remaining with fatigue increased over time, with HR of 1.69 (95% CI: 0.89-3.20) and 2.43 (95% CI: 1.49-3.95) for women with moderate and severe symptoms, respectively.

Multivariate analysis showed cough and myalgia as independent risk factors in G1. Fatigue prevalence was significantly higher in G1 compared to G2 and G3. Post-viral fatigue prevalence is higher in women infected during pregnancy; fatigue’s risk and duration increased with the severity of infection.

Source: Oliveira AMDSS, Carvalho MA, Nacul L, Cabar FR, Fabri AW, Peres SV, Zaccara TA, O’Boyle S, Alexander N, Takiuti NH, Mayaud P, Brizot ML, Francisco RPV. Post-Viral Fatigue Following SARS-CoV-2 Infection during Pregnancy: A Longitudinal Comparative Study. Int J Environ Res Public Health. 2022 Nov 26;19(23):15735. doi: 10.3390/ijerph192315735. PMID: 36497810; PMCID: PMC9737157. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9737157/ (Full text)

Clinical effects of wasabi extract containing 6-MSITC on myalgic encephalomyelitis/chronic fatigue syndrome: an open-label trial

Abstract:

Background: Wasabi (Eutrema japonicum) is a common pungent spice used in Japan. 6-Methylsulfinylhexyl isothiocyanate (6-MSITC) found in the rhizome of wasabi has been shown to have anti-inflammatory and antioxidant effects, as well as improve neuroinflammation and memory. Therefore, we hypothesized that these effects would be beneficial for treating myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The present study was conducted to investigate the effectiveness of wasabi extract containing 6-MSITC on ME/CFS in an open-label trial.

Methods: Fifteen patients (3 males, 12 females, 20-58 years old) were orally administered wasabi extract (9.6 mg of 6-MSITC/day) for 12 weeks. The following parameters and test results were compared pre- and post-treatment: performance status (PS), self-rating questionnaires, pressure pain threshold (PPT) on the occiput, Trail Making test-A (TMT-A), and hemodynamic patterns determined by an active standing test.

Results: After treatment with 6-MSITC, PS improved significantly (p = 0.001). Although the scores on the 11-item Chalder Fatigue scale (CFS-11) and numerical rating scale (NRS) of fatigue did not show significant changes, subjective symptoms improved significantly, including headache frequency (4.1 to 3.0 times/week, p = 0.001) and myalgia (4.1 to 2.4 times/week, p = 0.019), NRS brain fog scores (5.7 to 4.5, p = 0.011), difficulty finding appropriate words (4.8 to 3.7, p = 0.015), photophobia (4.8 to 3.5, p = 0.008), and the Profile of Mood Status vigor score (46.9 to 50.0, p = 0.045). The PPT of the right occiput (17.3 to 21.3 kPa, p = 0.01) and TMT-A scores (53.0 to 38.1 s, p = 0.007) also changed, suggesting reduced pain sensitivity, and improved cognitive function, respectively. Orthostatic patterns determined by a standing test did not show remarkable changes. There were no serious adverse reactions.

Conclusion: This study suggests that 6-MSITC improves PS as well as subjective symptoms such as pain and cognitive dysfunction, and psychological vitality of patients with ME/CFS. It also improved cognitive performance and increased pain thresholds in these patients. 6-MSITC may be a promising therapeutic option especially for improving cognitive dysfunction associated with ME/CFS.

Source: Oka T, Yamada Y, Lkhagvasuren B, Nakao M, Nakajima R, Kanou M, Hiramatsu R, Nabeshima YI. Clinical effects of wasabi extract containing 6-MSITC on myalgic encephalomyelitis/chronic fatigue syndrome: an open-label trial. Biopsychosoc Med. 2022 Dec 12;16(1):26. doi: 10.1186/s13030-022-00255-0. PMID: 36510244. https://bpsmedicine.biomedcentral.com/articles/10.1186/s13030-022-00255-0 (Full text)