Category: Overlapping Illnesses

Post-acute COVID-19 syndrome and gut dysbiosis linger beyond 1 year after SARS-CoV-2 clearance

We recently published in Gut to show that gut dysbiosis persisted for at least 6 months in patients with post-acute COVID-19 syndrome (PACS).1 Murine and human studies have also reported microbial alterations associated with different PACS symptoms.2 3 With the pandemic entering its third year, PACS could potentially affect recovered individuals for over 1 year.4 It remains unknown whether PACS-associated gut dysbiosis would also linger for such a long time.

Here, we conducted a prospective study to determine long-term alterations in the gut microbiome of patients with COVID-19 using shotgun metagenomic sequencing (online supplemental materials). A total of 155 patients with COVID-19 in Hong Kong were followed up for an average of 14 months after SARS-CoV-2 viral clearance, and 155 age-matched, sex-matched and body mass index-matched subjects without COVID-19 were recruited as controls. Patients with COVID-19 were infected with the original or earlier variants of SARS-CoV-2 from January 2020 to February 2021. Consistent with previous finding that 76.4% of patients had PACS 6 months after recovery from acute COVID-19,1 we found that the prevalence of PACS was 78.7% at an average of 14-month (IQR 11–18 months) follow-up. The three most common symptoms were fatigue (50.9%), memory problems (44.5%) and difficulty in sleeping (35.5%, figure 1A). Gut dysbiosis in these patients did not fully recover. Both bacteria diversity (p=0.0036, figure 1B) and richness (p=0.00032, figure 1C) of patients with COVID-19 were still significantly lower than that of controls. Principal coordinates analysis of beta diversity also showed distinct separation of patients with COVID-19 from controls (F=8.3822, p<0.001, figure 1D). These observations suggest persistent gut dysbiosis beyond 1 year in patients with PACS

Read the rest of this article HERE.

Source: Su Q, Lau RI, Liu Q, Chan FKL, Ng SC. Post-acute COVID-19 syndrome and gut dysbiosis linger beyond 1 year after SARS-CoV-2 clearance. Gut. 2022 Aug 8:gutjnl-2022-328319. doi: 10.1136/gutjnl-2022-328319. Epub ahead of print. PMID: 35940857. https://gut.bmj.com/content/early/2022/08/08/gutjnl-2022-328319 (Full text)

Persistence of somatic symptoms after COVID-19 in the Netherlands: an observational cohort study

Abstract:

Background: Patients often report various symptoms after recovery from acute COVID-19. Previous studies on post-COVID-19 condition have not corrected for the prevalence and severity of these common symptoms before COVID-19 and in populations without SARS-CoV-2 infection. We aimed to analyse the nature, prevalence, and severity of long-term symptoms related to COVID-19, while correcting for symptoms present before SARS-CoV-2 infection and controlling for the symptom dynamics in the population without infection.

Methods: This study is based on data collected within Lifelines, a multidisciplinary, prospective, population-based, observational cohort study examining the health and health-related behaviours of people living in the north of the Netherlands. All Lifelines participants aged 18 years or older received invitations to digital COVID-19 questionnaires. Longitudinal dynamics of 23 somatic symptoms surrounding COVID-19 diagnoses (due to SARS-CoV-2 alpha [B.1.1.7] variant or previous variants) were assessed using 24 repeated measurements between March 31, 2020, and Aug 2, 2021. Participants with COVID-19 (a positive SARS-CoV-2 test or a physician’s diagnosis of COVID-19) were matched by age, sex, and time to COVID-19-negative controls. We recorded symptom severity before and after COVID-19 in participants with COVID-19 and compared that with matched controls.

Findings: 76 422 participants (mean age 53·7 years [SD 12·9], 46 329 [60·8%] were female) completed a total of 883 973 questionnaires. Of these, 4231 (5·5%) participants had COVID-19 and were matched to 8462 controls. Persistent symptoms in COVID-19-positive participants at 90-150 days after COVID-19 compared with before COVID-19 and compared with matched controls included chest pain, difficulties with breathing, pain when breathing, painful muscles, ageusia or anosmia, tingling extremities, lump in throat, feeling hot and cold alternately, heavy arms or legs, and general tiredness. In 12·7% of patients, these symptoms could be attributed to COVID-19, as 381 (21·4%) of 1782 COVID-19-positive participants versus 361 (8·7%) of 4130 COVID-19-negative controls had at least one of these core symptoms substantially increased to at least moderate severity at 90-150 days after COVID-19 diagnosis or matched timepoint.

Interpretation: To our knowledge, this is the first study to report the nature and prevalence of post-COVID-19 condition, while correcting for individual symptoms present before COVID-19 and the symptom dynamics in the population without SARS-CoV-2 infection during the pandemic. Further research that distinguishes potential mechanisms driving post-COVID-19-related symptomatology is required.

Funding: ZonMw; Dutch Ministry of Health, Welfare, and Sport; Dutch Ministry of Economic Affairs; University Medical Center Groningen, University of Groningen; Provinces of Drenthe, Friesland, and Groningen.

Source: Ballering AV, van Zon SKR, Olde Hartman TC, Rosmalen JGM; Lifelines Corona Research Initiative. Persistence of somatic symptoms after COVID-19 in the Netherlands: an observational cohort study. Lancet. 2022 Aug 6;400(10350):452-461. doi: 10.1016/S0140-6736(22)01214-4. PMID: 35934007. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(22)01214-4/fulltext (Full text)

Post-COVID syndrome with fatigue and exercise intolerance: myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

in English, German

Background: A sizable part of post-COVID syndrome meets the diagnostic criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). A doubling of cases of ME/CFS within the next years is therefore projected.

Objectives: Presentation of the current state of knowledge on ME/CFS.

Materials and methods: Unsystematic review of the literature and of own contributions in research and patient care.

Results and conclusions: ME/CFS is a neuroimmunological disease, mostly infection-induced, usually persisting throughout life. Clinically it is characterized by fatigue lasting at least 6 months and the defining core feature of exercise intolerance (post-exertional malaise, PEM). Exercise intolerance is defined as a worsening of symptoms after (even mild) everyday exertion, which usually begins after several hours or on the following day, is still noticeable at least 14 h after exertion, and often lasts for several days (up to weeks or longer). Furthermore, ME/CFS is characterized by pain, disturbances of sleep, thinking and memory, and dysregulation of the circulatory, endocrine, and immune systems.

As a separate clinical entity, ME/CFS should be distinguished from chronic fatigue, which occurs as a symptom of a range of very different diseases. The diagnosis of ME/CFS is made clinically using established international diagnostic criteria and requires careful stepwise diagnosis to exclude other diagnoses. A causal therapy for ME/CFS has not been established; the focus is on symptoms relief, treatment of the often accompanying orthostatic intolerance, and assistance with anticipatory energy management (pacing).

Source: Renz-Polster H, Scheibenbogen C. Post-COVID-Syndrom mit Fatigue und Belastungsintoleranz: Myalgische Enzephalomyelitis bzw. Chronisches Fatigue-Syndrom [Post-COVID syndrome with fatigue and exercise intolerance: myalgic encephalomyelitis/chronic fatigue syndrome]. Inn Med (Heidelb). 2022 Aug;63(8):830-839. German. doi: 10.1007/s00108-022-01369-x. Epub 2022 Jul 13. PMID: 35925074. https://pubmed.ncbi.nlm.nih.gov/35925074/  https://link.springer.com/article/10.1007/s00108-022-01369-x (Full text in German)

Serum of Post-COVID-19 Syndrome patients with or without ME/CFS differentially affects endothelial cell function in vitro

Abstract:

A proportion of COVID-19 reconvalescent patients develop post-COVID-19 syndrome (PCS) including a subgroup fulfilling diagnostic criteria of Myalgic encephalomyelitis/Chronic Fatigue Syndrome (PCS/CFS). Recently, endothelial dysfunction (ED) has been demonstrated in these patients, but the mechanisms remain elusive. Therefore, we investigated the effects of patients’ sera on endothelia cells (ECs) in vitro.
PCS (n = 17), PCS/CFS (n = 13), and healthy controls (HC, n = 14) were screened for serum anti-endothelial cell autoantibodies (AECAs) and dysregulated cytokines. Serum-treated ECs were analysed for the induction of activation markers and the release of small molecules by flow cytometry. Moreover, the angiogenic potential of sera was measured in a tube formation assay.
While only marginal differences between patient groups were observed for serum cytokines, AECA binding to ECs was significantly increased in PCS/CFS patients. Surprisingly, PCS and PCS/CFS sera reduced surface levels of several EC activation markers. PCS sera enhanced the release of molecules associated with vascular remodelling and significantly promoted angiogenesis in vitro compared to the PCS/CFS and HC groups. Additionally, sera from both patient cohorts induced the release of molecules involved in inhibition of nitric oxide-mediated endothelial relaxation.
Overall, PCS and PCS/CFS patients′ sera differed in their AECA content and their functional effects on ECs, i.e., secretion profiles and angiogenic potential. We hypothesise a pro-angiogenic effect of PCS sera as a compensatory mechanism to ED which is absent in PCS/CFS patients.
Source: Flaskamp L, Roubal C, Uddin S, Sotzny F, Kedor C, Bauer S, Scheibenbogen C, Seifert M. Serum of Post-COVID-19 Syndrome Patients with or without ME/CFS Differentially Affects Endothelial Cell Function In Vitro. Cells. 2022; 11(15):2376. https://doi.org/10.3390/cells11152376  https://www.mdpi.com/2073-4409/11/15/2376/htm (Full text)

Prevalence of peripheral neuropathy and myopathy in patients post-COVID-19 infection

Abstract:

Background: Severe acute respiratory syndrome (SARS-CoV-2), caused by the Coronavirus 2019 (COVID-19), has become a life-threatening epidemic, affecting multiple organs, including the nervous system. Recent studies have documented that COVID-19-associated peripheral neuropathy is a common and frequent problem, with central and peripheral nervous system complications.

Objective: This work aims to evaluate the peripheral nerves and muscle involvement after COVID-19 infection, in addition to studying the prevalence rate and risk factors of their affection.

Methods: The study involved 400 patients, divided into 2 groups, with a history of COVID-19 infection with or without symptoms of neuromuscular affection, and 30 gender- and age-matched healthy volunteers were involved as controls. They were referred to the Department of Rheumatology and Rehabilitation for electro-diagnosis. All participants performed complete clinical examination and laboratory measures with an electrophysiological study.

Results: The prevalence of peripheral neuropathy and myopathy in post-COVID-19 patients was 56.3% among all patients. A significant difference was detected among patients of both groups regarding serum creatine phosphokinase level, clinical signs, and electrophysiologic findings of neuropathy and myopathy compared to the control group, with more prominent features among the symptomatic group. Histories of hospitalization, severe and long-lasting respiratory symptoms were risk factors for developing neuromuscular complications.

Conclusions: The present study could indicate that muscle involvement and peripheral nerve affection are common problems even among asymptomatic patients after COVID-19 infection, especially in the presence of any risk factors.

Source: Saif DS, Ibrahem RA, Eltabl MA. Prevalence of peripheral neuropathy and myopathy in patients post-COVID-19 infection. Int J Rheum Dis. 2022 Aug 1. doi: 10.1111/1756-185X.14409. Epub ahead of print. PMID: 35915515. https://onlinelibrary.wiley.com/doi/10.1111/1756-185X.14409 (Full text)

At the Root of 3 “Long” Diseases: Persistent Antigens Inflicting Chronic Damage on the Brain and Other Organs in Gulf War Illness, Long-COVID-19, and Chronic Fatigue Syndrome

Abstract:

Several foreign antigens such as those derived from viruses and bacteria have been linked to long-term deleterious effects on the brain and other organs; yet, health outcomes subsequent to foreign antigen exposure vary depending in large part on the host’s immune system, in general, and on human leukocyte antigen (HLA) composition, in particular.

Here we first provide a brief description of 3 conditions characterized by persistent long-term symptoms, namely long-COVID-19, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), and Gulf War Illness (GWI), followed by a brief overview of the role of HLA in the immune response to foreign antigens. We then discuss our Persistent Antigen (PA) hypothesis and highlight associations between antigen persistence due to HLA-antigen incongruence and chronic health conditions in general and the 3 “long” diseases above in particular. This review is not intended to cover the breadth and depth of symptomatology of those diseases but is specifically focused on the hypothesis that the presence of persistent antigens underlies their pathogenesis.

Source: James LM, Georgopoulos AP. At the Root of 3 “Long” Diseases: Persistent Antigens Inflicting Chronic Damage on the Brain and Other Organs in Gulf War Illness, Long-COVID-19, and Chronic Fatigue Syndrome. Neurosci Insights. 2022 Jul 22;17:26331055221114817. doi: 10.1177/26331055221114817. PMID: 35910083; PMCID: PMC9335483. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9335483/ (Full text)

COVID-19 May Be a Trigger for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

ALBANY, N.Y. (July 25, 2022) – UAlbany researcher Roxana Moslehi from the Department of Epidemiology and Biostatistics is conducting important investigations on myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) to better understand the illness, including its potential connection to cancer, auto-immune disease, and long-haul COVID-19.

According to the CDC, 1 in thirteen adults in the U.S. have COVID-19 symptoms lasting three or more months after contracting the virus—a condition often referred to as “long COVID.” However, research suggests that long COVID is complex, and in some instances may not be COVID-19 at all, but rather ME/CFS—triggered by COVID-19.

ME/CFS is a complex disabling disorder with no known treatment. Between 25 and 50 percent of those with the illness are bed or housebound for extended periods of time, with overwhelming fatigue that does not diminish after resting and difficulty performing daily tasks. Prior to the COVID-19 pandemic, it was estimated that up to 3.4 million people in the US suffered from the illness—the range is large due to the difficulty in diagnosing the disease as it is often dismissed or assumed to be another disorder.

Since ME/CFS is believed to be triggered by the onset of an infectious illness, research suggests that COVID-19 may be a trigger for ME/CFS. The chronic long-haul COVID-19 symptoms that some people report as following the resolution of their acute illness have similarities to symptoms of ME/CFS, such as persistent fatigue, sleep dysfunction, cognitive impairment, impaired memory, and more.

“It is estimated that in the wake of the COVID-19 pandemic, more than 10 million new ME/CFS cases may be triggered around the world,” Moslehi explains. “This makes it urgent to identify risk factors and underlying biologic mechanisms for this condition along with its potential connection to COVID-19.”

Moslehi conducted a molecular epidemiologic investigation of ME/CFS (funded by an NIH research grant awarded to her) to better understand the illness, providing the most compelling evidence to date that ME/CFS may be an auto-immune disorder. She compared people who developed ME/CFS after having an infectious illness with a group of individuals without ME/CFS (called the control group). She looked at various intrinsic factors related to the participants’ health, such as personal history of allergy and asthma, and extrinsic or environmental factors such as exposure to contaminants. She also assessed the prevalence of illnesses such as auto-immune diseases and cancer in their families, levels of serum immune system markers such as cytokines, and molecular evidence of viral reactivation such as mono flare-ups.

The study, published in the proceedings of the American Society of Human Genetics (ASHG), the International Genetic Epidemiology Society (IGES) and the American Association for Cancer Research (AACR), found that those with ME/CFS were five times more likely to have a family history of auto-immune diseases than the control group. ME/CFS was also associated with an increased risk of early-onset cancer (diagnosed before 60 years old) among the first-degree relatives. ME/CFS was associated with certain risk factors such as a history of allergies requiring medication and exposure to contaminants. The analysis by the Moslehi lab also identified a panel of cytokines that predict the risk of ME/CFS with high accuracy. A couple of the identified cytokines are involved in inflammatory processes and have been linked to other auto-immune diseases.

“Our multidimensional analysis of pedigree, epidemiologic, and molecular data not only provides the most objective evidence to date that ME/CFS may be an auto-immune disease— it provides etiologic clues and leads for prevention” says Moslehi. “In addition, our results may enable defining a subset of COVID-19 patients, who are at risk of developing long COVID or ME/CFS, for targeted monitoring and/or therapy.”

More recently, Moslehi, in collaboration with her colleagues at the NIH, obtained two additional NIH (intramural) grants to continue her research on ME/CFS. Through these grants, the DNA and RNA of ME/CFS cases and controls have been sequenced and will be analyzed to identify genes and genetic variations that are associated with ME/CFS.

“The ultimate goal is to conduct an integrative analysis of multi-omics (genomics, proteomics, transcriptomics) data to gain deeper insight into the biologic mechanisms of ME/CFS and identify druggable targets for ME/CFS therapy,” she says.

 

Histamine production by the gut microbiota induces visceral hyperalgesia through histamine 4 receptor signaling in mice

Abstract:

The gut microbiota has been implicated in chronic pain disorders, including irritable bowel syndrome (IBS), yet specific pathophysiological mechanisms remain unclear. We showed that decreasing intake of fermentable carbohydrates improved abdominal pain in patients with IBS, and this was accompanied by changes in the gut microbiota and decreased urinary histamine concentrations.

Here, we used germ-free mice colonized with fecal microbiota from patients with IBS to investigate the role of gut bacteria and the neuroactive mediator histamine in visceral hypersensitivity. Germ-free mice colonized with the fecal microbiota of patients with IBS who had high but not low urinary histamine developed visceral hyperalgesia and mast cell activation. When these mice were fed a diet with reduced fermentable carbohydrates, the animals showed a decrease in visceral hypersensitivity and mast cell accumulation in the colon. We observed that the fecal microbiota from patients with IBS with high but not low urinary histamine produced large amounts of histamine in vitro.

We identified Klebsiella aerogenes, carrying a histidine decarboxylase gene variant, as a major producer of this histamine. This bacterial strain was highly abundant in the fecal microbiota of three independent cohorts of patients with IBS compared with healthy individuals. Pharmacological blockade of the histamine 4 receptor in vivo inhibited visceral hypersensitivity and decreased mast cell accumulation in the colon of germ-free mice colonized with the high histamine-producing IBS fecal microbiota. These results suggest that therapeutic strategies directed against bacterial histamine could help treat visceral hyperalgesia in a subset of patients with IBS with chronic abdominal pain.

Source: De Palma G, Shimbori C, Reed DE, Yu Y, Rabbia V, Lu J, Jimenez-Vargas N, Sessenwein J, Lopez-Lopez C, Pigrau M, Jaramillo-Polanco J, Zhang Y, Baerg L, Manzar A, Pujo J, Bai X, Pinto-Sanchez MI, Caminero A, Madsen K, Surette MG, Beyak M, Lomax AE, Verdu EF, Collins SM, Vanner SJ, Bercik P. Histamine production by the gut microbiota induces visceral hyperalgesia through histamine 4 receptor signaling in mice. Sci Transl Med. 2022 Jul 27;14(655):eabj1895. doi: 10.1126/scitranslmed.abj1895. Epub 2022 Jul 27. PMID: 35895832. https://pubmed.ncbi.nlm.nih.gov/35895832/

Histamine-producing gut bacteria can trigger chronic abdominal pain

Press Release: Hamilton, ON (July 27, 2022) – Researchers from McMaster University and Queen’s University have discovered a gut bacterial ‘super-producer’ of histamine that can cause pain flare-ups in some patients with irritable bowel syndrome (IBS).

The culprit is what has now been named Klebsiella aerogenes, the McMaster-Queen (MQ) strain, identified in up to 25 per cent of gut microbiota samples from patients with IBS. Researchers examined stool microbiota samples from both Canadian and American patient cohorts.

“We followed up these patients for several months and found high levels of stool histamine at the time when the patients reported severe pain, and low stool histamine when they were pain-free,” said senior author Premysl Bercik, professor of medicine of McMaster’s Michael G. DeGroote School of Medicine and a gastroenterologist.

The McMaster-Queen’s research team pinpointed the bacterium Klebsiella aerogenes as the key histamine producer by studying germ-free mice colonized with gut microbiota from patients with IBS. They also colonized some mice with gut microbiota from healthy volunteers as a control group.

The study found that the bacterium Klebsiella aerogenes converts dietary histidine, an essential amino acid present in animal and plant protein, into histamine, a known mediator of pain.

The bacterial histamine then activates the gut immune system through histamine-4 receptor, which draws immune mast cells into the intestines. These activated mast cells produce even more histamine and other pain-signalling mediators, triggering inflammation and pain.

“Now that we know how the histamine is produced in the gut, we can identify and develop therapies that target the histamine producing bacteria,” said first author Giada de Palma, assistant professor of medicine at McMaster.

The study found that when the mice colonized with histamine producing bacteria were fed a diet low in fermentable carbohydrates, bacterial histamine production dramatically decreased. This was due to change in bacterial fermentation and acidity within the gut, which inhibited the bacterial enzyme responsible for histamine production.

Bercik said that these results explain the beneficial effects of a low fermentable diet observed in patients with IBS.

It is known that patients with IBS have more mast cells in their intestines, and that some of them improve with treatments targeting mast cells or histamine, such as mast cell stabilizers or antihistamines.

“Although mast cell treatment in IBS has been explored, a novel approach based on our research would be targeting the bacterial histamine production or H4R pathways,” Bercik said.

The McMaster-Queen’s study explains why increased mast cells are found in IBS and suggests that H4 receptor pathway plays a major role in this process.

“If we block the H4 receptors, then we can prevent recruitment of mast cells to the colon and subsequently the development of abdominal pain,” said senior co-author Stephen Vanner, professor of medicine at Queen’s University.

“Many but not all IBS patients will benefit from therapies targeting this histamine driven pathway,” said co-first author David Reed, assistant professor of medicine at Queen’s. Reed said that one or more biomarkers of this pathway could be used to find the patients most likely to benefit.

The McMaster-Queens study was funded by the Canadian Institutes of Health Research.

The study was published in the journal Science Translational Medicine on July 27.

Click HERE to read the study.