1. A New Disease Cluster: Postural Orthostatic Tachycardia Syndrome, Ehlers-Danlos Syndrome, and Mast Cell Activation Syndrome
Ingrid Cheung, Juan Guzman, Roberto Mendoza-Londono, Scott Walsh, Karan Gandhi, Peter Vadas
The ILC Ehlers Danlos & Chronic Pain Conference
November 4, 2017
Ingrid Cheung4 MHI, Juan Guzman MD1, Roberto Mendoza Londono MD2, Scott Walsh MD3, Karan Gandhi4 and Peter Vadas MD PhD4 
1Syncope and Autonomic Disorders Unit, Department of Medicine, McMaster University, Hamilton General Hospital, Hamilton, ON, Canada
2Division of Clinical and Metabolic Genetics, Department of Paediatrics, The Hospital for Sick Children and University of Toronto, Toronto, ON, Canada
3Division of Dermatology, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
4Division of Allergy and Clinical Immunology, St. Michael’s Hospital, Toronto, ON, Canada
- audience: 60-70% patients, 20% physicians
- limit info (no more than 5-6 lines per slide), make sure font is big enough

2. Rationale
Symptoms suggestive of MCAS observed in patients who have POTS and/or EDS
Increased levels of urine biomarkers in people with POTS
Connective tissue abnormalities and dysautonomia in people with elevated tryptase levels
We undertook a prospective study to examine the potential linkage between these 3 conditions
- observations from 2 papers in the lit + our abstract
- Shibao et al. 2005
- Josh Milner et al. 2014, 2016
- MCA in those with increased serum tryptase = monoclonal MCAS (D816V c-Kit proto-oncogene mutation in exon 17)
- case definitions used in order to guide the study: "for our research purposes, here were the diagnostic criteria we used"
- 1 minute per condition --> "too fast? feel free to ask me questions at the end"

3. Hypermobile Type Ehlers-Danlos Syndrome (hEDS)
Clinical manifestations:*
Beighton hypermobility score ≥ 5/9
Chronic joint pain and recurrent subluxations
Absence of atrophic, widened scarring reactions in the skin
*Note: Patients were ascertained before publication of the revised guidelines for the diagnosis of hEDS
- because this study had been started a few years ago (summer 2014), we used the criteria defined by the 1997 Villefranche nosology
- diagnostic criteria doesn't conform to the most recent iteration of hEDS diagnostic criteria

4. Postural Orthostatic Tachycardia Syndrome (POTS)
Characterized by:
Frequent symptoms that occur with standing
Heart rate increase ≥ 30 beats per minute upon standing from lying down
Absence of orthostatic hypotension
- e.g. pre-syncope or syncope, lightheadedness, palpitations, tremors, generalized weakness, blurred vision
- for more than 30 seconds
- “orthostatic hypotension” = significant decrease in BP within 3 minutes of standing from sitting/supine

5. Mast Cell Activation Syndrome (MCAS)
Cem Akin (2010)’s proposed diagnostic criteria:
Validated symptoms of mast cell activation (≥ 2 organ systems)
Ruled out primary / secondary causes of mast cell activation
Elevated serum or urinary markers of mast cell activation
Good therapeutic response to anti-mediator therapy
- Of course, patients showed more symptoms than just the ones that mentioned here, BUT we chose specific symptoms that were published in 2010 review by Cem Akin
- based our study on these symptoms because they were validated against bone marrow biopsies of those with monoclonal MCAS
- POTS/EDS have non-monoclonal MCAS, but it's same mediators that come from mast cells -> manifestations will not be any different

6. Phase I: Methods
Participants recruited from an online, North American patient support group
Recruitment criteria:
POTS: documented clinical diagnosis, confirmation via tilt-table test
hEDS: documented diagnosis, Beighton hypermobility score ≥5/9
MCAS: assessed presentation of validated symptoms of mast cell mediator release
Phase I: we looked for patients who had documented diagnoses of POTS and hEDS, based on ___ + validated symptoms of MCAS
- patient support group for patients with symptoms of POTS and an inherited connective tissue disorder
- used previous iteration of EDS diagnostic criteria
- assessed presence of validated MCAS symptoms via distributed questionnaire

7. Phase I: Results Demographics:
All study participants were female, >25 years old
Diagnoses:
Total number of patients = 15
Demographics:
All female
All >25 years old
Cohort: total 15 patients

8. Phase I: Results POTS (12) Demographics:
All study participants were female, >25 years old
Diagnoses:
Total number of patients = 15
Patients with POTS = 12
- 12 patients with POTS diagnoses

9. Phase I: Results POTS (3) POTS + hEDS (9) Demographics:
All study participants were female, >25 years old
Diagnoses:
Total number of patients = 15
Patients with POTS = 12
Patients with POTS + hEDS = 9
POTS +
hEDS
(9)
Of these 12 patients with POTS:
3 had only POTS diagnoses
9 had diagnoses of POTS and hEDS

10. Phase I: Results POTS (3) POTS + hEDS + MCAS (6) POTS + hEDS (3)
Demographics:
All study participants were female, >25 years old
Diagnoses:
Total number of patients = 15
Patients with POTS = 12
Patients with POTS + hEDS = 9
Patients with POTS + hEDS + MCAS symptoms = 6
POTS +
hEDS
(3)
Of these 9 patients with POTS and hEDS: 6 showed validated symptoms of MCAS
“Based on this data, there seems to be a strong linkage between these 3 conditions”
- caveats: given that the patients were self-referred and women are more likely to participate
- results were suggestive, but not conclusive so we undertook a prospective study

11. Phase II: Methods
Participants recruited from Dr. Vadas’ allergy and clinical immunology clinic
Recruitment criteria:
POTS: clinical diagnosis based on criteria from the Heart Rhythm Society
hEDS: diagnosis based on 1997 Villefranche nosology + structural collagen abnormalities
MCAS: diagnosis confirmed through elevated serum and/or urinary markers + validated symptoms + response to anti-mediator therapy
- patients recruited from St. Michael’s Hospital, Toronto, ON
- POTS: Heart Rhythm Society (2015)

12. hEDS:
- because this study had been started a few years ago (summer 2014), diagnostic criteria doesn't conform to the most iteration of hEDS diagnostic criteria, hence we used the older criteria
- may not conform to most recent criteria from this year, but they all clearly fall on hypermobile spectrum disorder based on symptoms + skin biopsies that showed structural collagen abnormalities (flower-like collagen fibrils, uneven diameter of collagen fibrils)

13. hEDS:
- because this study had been started a few years ago (summer 2014), diagnostic criteria doesn't conform to the most iteration of hEDS diagnostic criteria, hence we used the older criteria
- may not conform to most recent criteria from this year, but they all clearly fall on hypermobile spectrum disorder based on symptoms + skin biopsies that showed structural collagen abnormalities (flower-like collagen fibrils, uneven diameter of collagen fibrils)

14. Phase II: Methods
Participants recruited from Dr. Peter Vadas’ allergy and clinical immunology clinic
Recruitment criteria:
POTS: clinical diagnosis based on criteria from the Heart Rhythm Society
hEDS: diagnosis based on 1997 Villefranche nosology + structural collagen abnormalities
MCAS: diagnosis confirmed through elevated serum and/or urinary markers + validated symptoms + response to anti-mediator therapy
- MCAS proposed diagnostic criteria: Cem Akin (2010)

15. Phase II: Results All patients showed: Normal basal tryptase levels
Elevated urinary markers of mast cell activation
All patients reported:
Positive response to anti-mediator therapy
- Normal tryptase = non-monoclonal MCA (i.e. NOT mastocytosis)
- urinary markers: urine methylhistamine
- improvement in MCAS-associated symptoms over the course of therapy

16. Phase II: Results Baseline Symptoms
Patient
Cutaneous
Gastrointestinal
Respiratory
Cardiovascular 1
Yes No 2 3 4 5
Initial visit:
- gather baseline information + prescribe antihistamines
- these 5 patients have been well-characterized, since then we've added in an additional 4 patients, for a total of 9

17. Phase II: Results Post-Intervention Symptoms
Patient
Cutaneous
Gastrointestinal
Respiratory
Cardiovascular 1
No change
N/A
Complete 2
Partial 3 4 5
Subsequent visits:
- symptom monitoring + addition of mast cell stabilizers and/or anti-leukotriene blockers, as needed
- specific meds added were directed towards that individual's specific symptoms
- e.g. systemic -> MC stabilizer (ketotifen); GI -> Nalcrom (if GI tract doesn’t seem to be absorbing other drugs well)
- patients were seen back as often as necessary to stabilize symptoms and optimize treatment
- when patients felt symptoms were optimized, they were seen less often
“These positive responses to mast cell-directed therapy in patients with POTS and hEDS strongly supports co-segregation with MCAS”
- anti-mediator therapy appears to be most effective for cutaneous and respiratory symptoms

18. Discussion There has been little work published in this area
Shibao et al. (2005)
Milner et al. (2014, 2016)
Afrin et al. (March 2017)
Our findings suggest that those with POTS and/or hEDS have a higher risk of also having a diagnosis of MCAS
Anti-mediator therapy may be an effective treatment to control MCAS-associated symptoms in these patients
- there has been almost no work published in this area as of yet
- Shibao et al. (2005): 1 paper that suggests POTS+MCAS association
- patients with POTS had higher urinary methylhistamine levels + improved clinical symptoms in response to histamine receptor blockers
- Josh Milner et al. (2014, 2016) - 2 papers from NIH
- looked at different but related patients (familial increase in alpha tryptase with CT manifestations, POTS-like symptoms)
- MCA in those with increased serum tryptase = monoclonal MCAS (D816V c-Kit proto-oncogene mutation in exon 17)
- patients with a familial increase in α-tryptase with connective tissue manifestations and POTS-like symptoms
- we looked a slightly different patient population -> we focused on patients with normal tryptase levels
- Dr. Afrin paper (March 2017): mast cell disorders in EDS
- role of mast cells in EDS and dysautonomia

19. Study Conclusions
There is a lot of overlap between symptoms of hEDS, POTS, and MCAS
Therapies must be directed at each of these 3 diagnoses individually in order to optimize treatment and quality of life
- there is a great deal of overlap in symptoms between EDS and POTS and MCAS, but in order to optimize treatment and quality of life, each of these 3 diagnoses has to be addressed individually/therapies have to be directed to each of the 3 diagnoses individually

20. Acknowledgements Co-Author Affiliation(s) Juan Guzman MD, MSc, FRCPC
Syncope and Autonomic Disorders Unit,
Department of Medicine,
McMaster University,
Hamilton General Hospital
Roberto Mendoza-Londono
MD, MSc, FCCMG, FRCPC
Division of Clinical and Metabolic Genetics,
Department of Paediatrics,
The Hospital for Sick Children,
University of Toronto
Scott Walsh
MD, PhD, FRCPC
Division of Dermatology,
Sunnybrook Health Sciences Centre
Karan Gandhi
Division of Allergy and Clinical Immunology,
St. Michael’s Hospital
Peter Vadas

21. Next Steps Accrue more patients for this study
Formal quality of life assessments to assess affect of mast cell- mediated therapy on patients’ quality of life
Molecular studies to investigate mechanism that causes mast cell activation in patients with hEDS and POTS
- What now? What are we going to do next?
- we’re going to accrue more patients (more robust data)
- formal quality of life assessments of those using mast cell-mediated therapy to see how this translates to improvement in quality of life
- we’re involved in molecular studies to see what it is (molecular mechanism) that causes mast cell activation in people who have EDS and POTS (not prepared to talk publicly about what these studies are)

22. Limitations Revised hEDS nosology
More narrow definition
Small sample size in both study phases
Lack of statistical power
Limits generalizability
Selection bias
Phase I: self-identified patients
Phase II: recruitment from a single, specialized, allergy / immunology practice
Recall bias
Patient self-reported symptoms
Placebo effect / Co-therapies
Concurrent treatment for POTS and/or hEDS diagnoses

23. MCAS: Diagnostic Criteria
1. Multiple mast cell mediator-induced symptoms, affecting ≥2 of the following organ systems:
Dermatologic: itching, flushing, urticaria
Gastrointestinal: crampy abdominal pain, nausea/vomiting, diarrhea
Cardiovascular: tachycardia, labile blood pressure, syncope/pre-syncope
Respiratory: wheezing, cough, chest tightness, dyspnea
Naso-ocular: conjunctival injection, severely itchy eyes, nasal congestion
2. Rule out primary and secondary causes of mast cell activation, such as:
Primary: systemic mastocytosis, mast cell clonality
Secondary: allergy or other underlying mast cell activation trigger
3. Evidence of abnormal levels of validated urinary or serum markers of mast cell activation, including:
Absence of elevated total serum tryptase (<11.4 ng/mL)
Increase in the following less specific markers: 24-hour urine histamine metabolites, prostaglandin D2, 11-β-prostaglandin F2α
4. Decreased frequency or severity of mast cell activation-related symptoms, in response to anti-mast cell mediator therapy, such as:
H1- and H2-histamine receptor antagonists: diphenhydramine, loratadine, ranitidine
Anti-leukotriene blockers: montelukast, zafirlukast
Mast cell stabilizers: cromolyn sodium, ketotifen

24. hEDS: Collagen Abnormalities (under TEM)