MTHFR and LC, CFS, POTS, MCAS, SIBO, EDS: Methylating the Alphabet (preprint)

Long Covid (LC), Chronic Fatigue Syndrome (CFS), Postural Orthostatic Tachycardia Syndrome (POTS), Mast Cell Activation Syndrome (MCAS), Small Intestine Bacterial Overgrowth (SIBO), and Ehlers-Danlos Syndrome (EDS) are all loosely connected, some poorly defined, some with overlapping symptoms. The female preponderance, the prominence of fatigue and chronic inflammation, and methylenetetrahydrofolate reductase (MTHFR) abnormalities may connect them all. Indeed differential methylation may lie at the root. Two - EDS and MTHFR - are genetic. But epigenetic factors may ultimately determine their phenotypic expression. Oxidative stress, overloaded mitochondria, an antioxidant and nutrient shortfall, and suboptimal gut microbiome appear to be the primary determinants. A deep dive into the folate and methionine cycles is undertaken in an attempt to connect these syndromes. The active forms of vitamin D and vitamins B2,3,6,9,12 are shown to be biochemically integral to optimal methylation and control of the epigenome. Their status largely determines the symptoms of abnormal MTHFR in all its phenotypes. The wider implications for aging, cancer, cardiovascular disease, neurodegenerative disease, and autoimmune disease are briefly explored.

A gene network implicated in the joint-muscle pain, brain fog, chronic fatigue, and bowel irregularity of Ehlers-Danlos and "long" COVID19 syndromes. (preprint)

Objectives Characterization of tissue laxity and dysautonomia symptoms in Ehlers-Danlos syndrome (EDS) uncovered similarities with those of post-infectious SARS-CoV-2 or long COVID19, prompting detailed comparison of their findings and influencing genes. Methods Holistic assessment of 1261 EDS outpatients for 120 history-physical findings populated a deidentified database that includes 568 patients with 317 variant genes obtained by commercial NextGen sequencing. Findings were compared to 15 of long COVID19 compiled in an extensive review, genes to 104 associated with COVID19 severity in multiple molecular studies. Results Fifteen symptoms common to Ehlers-Danlos versus long COVID19 ranged from brain fog (27-80 versus 30-70%), chronic fatigue (38-91; 30-60%), dyspnea (32-52; 29-52%) to irritable bowel (67-89; 14-78%), muscle weakness (22-49; 15-25%), and arthritis (32-94; 15-27%). Genes relevant to EDS included 6 identical to those influencing COVID19 severity (F2, LIFR, NLRP3, STAT1, T1CAM1, TNFRSF13B) and 18 similar including POLG-POLD4, SLC6A2-SLC6A20, and NFKB1-NFKB2. Both gene sets had broad genomic distribution, many mitochondrial genes influencing EDS and many involved with immunity-inflammation modifying COVID19 severity. Recurring DNA variants in EDS that merit evaluation in COVID19 resistance include those impacting connective tissue elements--51 in COL5 (joint), 29 in COL1/2/9/11 (bone), 13 in COL3 (vessel), and 18 in FBN1 (vessel-heart)--or neural function--93 in mitochondrial DNA, 28 in COL6/12, 16 in SCN9A/10A/11A, 14 in POLG, and 11 in genes associated with porphyria. Conclusions Holistic ascertainment of finding pattern and exome variation in EDS defined tissue laxity, neuromuscular, and autonomic correlations that transcend single abnormalities or types. Implied networks of nuclear and mitochondrial genes are linked to findings like brain fog, fatigue, and frailty in EDS, their similarity to long COVID19 supporting shared therapies for disorders affecting a minimum 0.1% of the global population.

Association of mast-cell-related conditions with hypermobile syndromes: a review of the literature.

Ehlers-Danlos syndrome (EDS) is a group of related connective tissue disorders consisting of 13 subtypes, each with its own unique phenotypic and genetic variation. The overlap of symptoms and multitude of EDS variations makes it difficult for patients to achieve a diagnosis early in the course of their disease. The most common form, hypermobile type EDS (hEDS) and its variant, hypermobile spectrum disorder (HSD), are correlated with rheumatologic and inflammatory conditions. Evidence is still needed to determine the pathophysiology of hEDS; however, the association among these conditions and their prevalence in hEDS/HSD may be explained through consideration of persistent chronic inflammation contributing to a disruption of the connective tissue. Aberrant mast cell activation has been shown to play a role in disruption of connective tissue integrity through activity of its mediators including histamine and tryptase which affects multiple organ systems resulting in mast cell activation disorders (MCAD). The overlap of findings associated with MCAD and the immune-mediated and rheumatologic conditions in patients with hEDS/HSD may provide an explanation for the relationship among these conditions and the presence of chronic inflammatory processes in these patients. It is clear that a multidisciplinary approach is required for the treatment of patients with EDS. However, it is also important for clinicians to consider the summarized symptoms and MCAD-associated characteristics in patients with multiple complaints as possible manifestations of connective tissue disorders, in order to potentially aid in establishing an early diagnosis of EDS.

Independent COL5A1 Variants in Cats with Ehlers-Danlos Syndrome.

We investigated four cats with similar clinical skin-related signs strongly suggestive of Ehlers-Danlos syndrome (EDS). Cases no. 1 and 4 were unrelated and the remaining two cases, no. 2 and 3, were reportedly siblings. Histopathological changes were characterized by severely altered dermal collagen fibers. Transmission electron microscopy in one case demonstrated abnormalities in the collagen fibril organization and structure. The genomes of the two unrelated affected cats and one of the affected siblings were sequenced and individually compared to 54 feline control genomes. We searched for private protein changing variants in known human EDS candidate genes and identified three independent heterozygous COL5A1 variants. COL5A1 is a well-characterized candidate gene for classical EDS. It encodes the proα1 chain of type V collagen, which is needed for correct collagen fibril formation and the integrity of the skin. The identified variants in COL5A1 are c.112_118+15del or r.spl?, c.3514A>T or p.(Lys1172*), and c.3066del or p.(Gly1023Valfs*50) for cases no. 1, 2&3, and 4, respectively. They presumably all lead to nonsense-mediated mRNA decay, which results in haploinsufficiency of COL5A1 and causes the alterations of the connective tissue. The whole genome sequencing approach used in this study enables a refinement of the diagnosis for the affected cats as classical EDS. It further illustrates the potential of such experiments as a precision medicine approach in animals with inherited diseases.

The psychological burden associated with Ehlers-Danlos syndromes: a systematic review.

CONTEXT: Ehlers-Danlos syndromes (EDS) are disorders of connective tissue that lead to a wide range of clinical presentations. While we are beginning to understand the association between EDS and psychological manifestations, it is critical that we further elucidate the relationship between the two. Understanding the correlation between EDS and mental health will better ensure swift diagnosis and effective treatment for patients. OBJECTIVES: This study aims to systematically examine and report the prevalence of psychiatric disorders in the EDS population. METHODS: The PubMed database was searched on June 14, 2021 for articles published from January 2011 to June 2021. We included original, evidence-based, peer-reviewed journal articles in English that reported information on psychiatric disorders among EDS patients. Psychiatric disorders and psychological conditions were limited to those included in the "psychology" and "mental disorders" Medical Subject Headings (MeSH) search terms defined by the National Library of Medicine. Publications identified utilizing this search strategy by M.K. were imported into the Covidence system, where they first underwent a title and abstract screening process by three independent reviewers (M.K., K.L., H.G.). During the full-text review, two independent reviewers read the full text of the questionable articles to assess their eligibility for inclusion. Studies were excluded if they did not meet our target objective or if they were not in English or if they were opinion pieces, conference abstracts, or review articles. Data were extracted from the shortlisted studies by reviewers. During the data extraction phase, the quality and risk of publication bias were assessed by two independent reviewers utilizing the National Institutes of Health (NIH) Study Quality Assessment Tools. Any disagreements in study selection, data extraction, or quality assessment were adjudicated via discussion between the two reviewers, utilizing a third reviewer as a decider if necessary. RESULTS: Out of 73 articles identified, there were no duplicates. A total of 73 records were screened, but only 40 articles were assessed in full text for eligibility. A total of 23 articles were ultimately included, which collectively discussed 12,298 participants. Ten (43.5%) of the included studies were cross-sectional in design, three (13.0%) were case reports, and three (13.0%) were retrospective chart reviews. The remaining seven (30.4%) articles were either case-control, cohort, qualitative, controlled observational, or validation studies. Twelve (52.2%) of the studies reported data on depression disorders, six of which reported prevalence data. Nine (39.1%) of the studies reported data on anxiety disorders, five of which reported prevalence data. Studies that reported nonprevalence data presented odds-ratio, mean scores on psychiatric evaluations, and other correlation statistics. Psychiatric disorders that were most reported in these articles were mood disorders (n=11), anxiety disorders (n=9), and neurodevelopmental disorders (n=7). Although the reports varied, the highest psychiatric prevalence reports in EDS patients involved language disorders (63.2%), attention-deficit/hyperactivity disorder (ADHD) (52.4%), anxiety (51.2%), learning disabilities (42.4%), and depression (30.2%). CONCLUSIONS: Although mood disorders were cited in more articles, the highest reported prevalence was for language disorders and ADHD. This discrepancy highlights the importance of performing more research to better understand the relationship between EDS and psychiatric disorders.

Peripartum considerations and challenges in the management of type IV Ehlers-Danlos syndrome.

Ehlers-Danlos syndrome (EDS) is an uncommon heterogenous autosomal dominant multisystemic connective tissue disorder, which may potentially present with life-threatening emergencies. The prevalence of EDS of all subtypes is from 1 in 10 000 to 1 in 20 000. Pregnancy in women with type IV EDS poses significant challenges, necessitating the care of multidisciplinary team. Potential complications of type IV EDS include arterial dissection, arterial aneurysm, visceral rupture, excessive bleeding, tissue fragility and delayed wound healing. We present an interesting case of a pregnant woman with type IV EDS who had previous cerebrovascular complications and had a successful delivery in our tertiary centre following a collaborative approach to her care.