The Mastocytosis Society Survey on Mast Cell Disorders: Patient Experiences and Perceptions

Psychological functioning and quality of life in patients with mastocytosis: A cross-sectional study

BACKGROUND

Psychological symptoms appear to be frequent among patients with mastocytosis and can significantly affect patient quality of life. However, it remains unclear whether and to which extent this may be the case.

OBJECTIVE

To investigate he presence and type of psychological symptoms and quality of life in patients with mastocytosis.

METHODS

In this cross-sectional cohort study of adult patients with mastocytosis, all patients completed the 36-item Short Form Health Survey (SF-36) and the 90-item Symptom Checklist (SCL-90). Results were compared with those of a healthy groups of patients with other diseases (chronic pain and cancer) and healthy populations.

RESULTS

Fifty patients were included in the study. Seventy percent had indolent systemic mastocytosis. Patients with mastocytosis scored significantly worse than a healthy norm group on the total SCL-90 and more specifically on the dimensions of depression, somatization, sleeping problems, and inadequacy of acting and thinking. Strikingly, patients with mastocytosis scored similarly to patients with cancer on the SF-36 subdomains of general health perception and vitality. However, no significant difference in the mental health subdomain of the SF-36 was found when compared with a healthy group.

CONCLUSION

In addition to the presence of psychological symptoms, the physical symptoms that are associated with mastocytosis also have a significant impact on the quality of life of patients with this disease. Therefore, correct treatment through symptom control and psychological counseling is necessary.

TRIAL REGISTRATION

EudraCT Identifier 2015-004604-37.

Melatonin Plus Folic Acid Treatment Ameliorates Reserpine-Induced Fibromyalgia: An Evaluation of Pain, Oxidative Stress, and Inflammation

Background: Fibromyalgia is a chronic condition characterized by increased sensory perception of pain, neuropathic/neurodegenerative modifications, oxidative, and nitrosative stress. An appropriate therapy is hard to find, and the currently used treatments are able to target only one of these aspects. Methods: The aim of this study is to investigate the beneficial effects of melatonin plus folic acid administration in a rat model of reserpine-induced fibromyalgia. Sprague–Dawley male rats were injected with 1 mg/kg of reserpine for three consecutive days and later administered with melatonin, folic acid, or both for twenty-one days. Results: Administration of reserpine led to a significant decrease in the nociceptive threshold as well as a significant increase in depressive-like symptoms. These behavioral changes were accompanied by increased oxidative and nitrosative stress. Lipid peroxidation was significantly increased, as well as nitrotyrosine and PARP expression, while superoxide dismutase, nonprotein thiols, and catalase were significantly decreased. Endogenously produced oxidants species are responsible for mast cell infiltration, increased expression pro-inflammatory mediators, and microglia activation. Conclusion: Melatonin plus acid folic administration is able to ameliorate the behavioral defects, oxidative and nitrosative stress, mast cell infiltration, inflammatory mediators overexpression, and microglia activation induced by reserpine injection with more efficacy than their separate administration.

Activity and Exercise Intolerance After Concussion: Identification and Management of Postural Orthostatic Tachycardia Syndrome

Supplemental Digital Content is Available in the Text.

Background and Purpose:

Postural orthostatic tachycardia syndrome (POTS) is increasingly recognized as a complication affecting recovery from concussion. Individuals with POTS demonstrate refractory dizziness, lightheadedness, cognitive dysfunction, fatigue, headache, chronic pain, nausea and gastrointestinal dysmotility, activity and exercise intolerance, syncope, and tachycardia. Subtypes of POTS may include hypovolemia, hyperadrenergic states, autonomic neuropathy, and underlying autoimmunity, which may variably impact response to rehabilitation in varying ways. The subtle presentation of POTS postconcussion is often mistaken for underlying anxiety, conversion disorder, or lack of motivation for recovery. This article will present clinical features of POTS that may arise after concussion, and propose a role for physical therapists in the diagnosis and management of POTS during concussion recovery.

Summary of Key Points:

Data recorded and entered into a database during clinic visits from a large pediatric institution indicate that 11.4% of individuals diagnosed with POTS report onset of symptoms within 3 months of sustaining a concussion. Activation of the sympathetic nervous system can result in lightheadedness, shortness of breath, chest pain, tachycardia, palpitations on standing or with exertion, and activity and exercise intolerance. Identified comorbidities in people with POTS such as joint hypermobility and autoimmune disorders can further influence recovery.

Recommendations for Clinical Practice:

Physical therapists may identify signs and symptoms of POTS in a subset of individuals who remain refractory to typical interventions and who exhibit symptom exacerbation with orthostatic activity. Incorporation of an individualized POTS exercise program into current established concussion interventions may be useful, with emphasis on initial recumbent exercises and ongoing physical therapy assessment of exercise tolerance for dosing of activity intensity and duration.

Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A211).

Mast Cells, Neuroinflammation and Pain in Fibromyalgia Syndrome

Fibromyalgia Syndrome (FMS) is a disorder of chronic, generalized muscular pain, accompanied by sleep disturbances, fatigue and cognitive dysfunction. There is no definitive pathogenesis except for altered central pain pathways. We previously reported increased serum levels of the neuropeptides substance P (SP) and its structural analogue hemokinin-1 (HK-1) together with the pro-inflammatory cytokines IL-6 and TNF in FMS patients as compared to sedentary controls. We hypothesize that thalamic mast cells contribute to inflammation and pain, by releasing neuro-sensitizing molecules that include histamine, IL-1β, IL-6 and TNF, as well as calcitonin-gene related peptide (CGRP), HK-1 and SP. These molecules could either stimulate thalamic nociceptive neurons directly, or via stimulation of microglia in the diencephalon. As a result, inhibiting mast cell stimulation could be used as a novel approach for reducing pain and the symptoms of FMS.

Recent advances in our understanding of mast cell activation - or should it be mast cell mediator disorders?

INTRODUCTION

An increasing number of patients present with multiple symptoms affecting many organs including the brain due to multiple mediators released by mast cells. These unique tissue immune cells are critical for allergic reactions triggered by immunoglobulin E (IgE), but are also stimulated (not activated) by immune, drug, environmental, food, infectious, and stress triggers, leading to secretion of multiple mediators often without histamine and tryptase. The presentation, diagnosis, and management of the spectrum of mast cell disorders are very confusing. As a result, neuropsychiatric symptoms have been left out, and diagnostic criteria made stricter excluding most patients. Areas covered: A literature search was performed on papers published between January 1990 and November 2018 using MEDLINE. Terms used were activation, antihistamines, atopy, autism, brain fog, heparin, KIT mutation, IgE, inflammation, IL-6, IL-31, IL-37, luteolin, mast cells, mastocytosis, mediators, mycotoxins, release, secretion, tetramethoxyluteolin, and tryptase. Expert opinion: Conditions associated with elevated serum or urine levels of any mast cell mediator, in the absence of comorbidities that could explain elevated levels, should be considered 'Mast Cell Mediator Disorders (MCMD).' Emphasis should be placed on the identification of unique mast cell mediators, and development of drugs or supplements that inhibit their release.

[Surgical interventions in patients with systemic mast cell activation disease : Recommendations for perioperative management]

BACKGROUND

Systemic mast cell activation disease (MCAD, prevalence 5-10%) is a multifactorial, polygenic disease with multisystemic symptoms that is characterized by an unregulated increased release of mast cell mediators and an accumulation of activated mast cells potentially in all organs and tissues. Due to the high prevalence of the disease, physicians involved in surgical, anesthesiological and interventional procedures are often unknowingly faced with MCAD patients experiencing unexpected preoperative, intraoperative and postoperative complications, if no mast cell-specific treatment regimens have been applied.

OBJECTIVE

The findings from a literature search, consensus recommendations of the various international expert groups and extensive own experience in the treatment of MCAD patients enable an empirical and evidence-based care of MCAD patients in association with invasive procedures.

RESULTS AND CONCLUSION

Due to the high prevalence of MCAD in the population, it can be assumed that patients with MCAD are correspondingly frequently represented in the surgical patient collective. When MCAD-specific peculiarities are preventively considered in the anesthesiological and surgical procedures in patients with proven or suspected mast cell disease, MCAD patients should not be classified as being at risk.

Mast cell tryptase - Marker and maker of cardiovascular diseases

Mast cells are tissue-resident cells, which have been proposed to participate in various inflammatory diseases, among them the cardiovascular diseases (CVDs). For mast cells to be able to contribute to an inflammatory process, they need to be activated to exocytose their cytoplasmic secretory granules. The granules contain a vast array of highly bioactive effector molecules, the neutral protease tryptase being the most abundant protein among them. The released tryptase may act locally in the inflamed cardiac or vascular tissue, so contributing directly to the pathogenesis of CVDs. Moreover, a fraction of the released tryptase reaches the systemic circulation, thereby serving as a biomarker of mast cell activation. Actually, increased levels of circulating tryptase have been found to associate with CVDs. Here we review the biological relevance of the circulating tryptase as a biomarker of mast cell activity in CVDs, with special emphasis on the relationship between activation of mast cells in their tissue microenvironments and the pathophysiological pathways of CVDs. Based on the available in vitro and in vivo studies, we highlight the potential molecular mechanisms by which tryptase may contribute to the pathogenesis of CVDs. Finally, the synthetic and natural inhibitors of tryptase are reviewed for their potential utility as therapeutic agents in CVDs.

Mastocytosis

Mastocytosis is a rare and underdiagnosed disorder characterized by mast cell proliferation in the tissues and organs of the body. The gastrointestinal manifestations of the disease can be noted in approximately 70%-80% of those patients diagnosed with the disorder. Symptomatic manifestations of systemic mastocytosis can either be triggered spontaneously or be precipitated by a variety of situations, stimuli, and exposures. Common gastrointestinal complaints include abdominal pain, diarrhea, nausea, vomiting, and gastrointestinal reflux disease. Substantial numbers of mast cells have been noted in patients who have been diagnosed with gastritis, ulcerative colitis, and Crohn disease. Irreversible, with symptoms that run the gamut from the merely annoying to the severely life-threatening, mastocytosis is a disease that prevents an individual from leading a normal life. As the prevalence of gastrointestinal symptomatology in those patients who have been diagnosed with mastocytosis is so significant, it is an important and relevant disease of which gastroenterology nurses should be cognizant.

The JAK1/JAK2- inhibitor ruxolitinib inhibits mast cell degranulation and cytokine release

BACKGROUND

Mastocytosis is characterized by the accumulation of aberrant mast cells (MC). Patients suffering from mastocytosis suffer from a wide range of symptoms due to increased levels of MC mediators. It would therefore be of great benefit to inhibit MC mediator release. However, to date there are few drugs available that are known to effectively lower MC mediator levels. The evidence for the involvement of the janus kinase 2 (JAK2)-signal transducer and activation of transcription 5 (STAT5) signalling pathway in MC activation is slowly accumulating. Interference with the JAK2-STAT5 pathway might inhibit MC mediator release. Ruxolitinib, a JAK1/JAK2 inhibitor, indeed decreases symptoms like pruritus and fatigue in patients with myeloproliferative neoplasms. Yet, detailed studies on how ruxolitinib affects human mast cell activity are lacking.

OBJECTIVE

To investigate the effect of JAK1/2-inhibition with ruxolitinib in the human mast cell lines LAD2 and HMC1.

METHODS

LAD2 and HMC1 were stimulated with substance P, codeine or the calcium ionophore A23817. The effect of ruxolitinib on mast cell degranulation (via measurement of β-hexosaminidase, histamine release and CD63 membrane expression) and IL-6, IL-13, MCP-1 and TNF-α production was investigated. The involvement of STAT5 activation was explored using the selective STAT5 inhibitor pimozide.

RESULTS

Ruxolitinib effectively inhibited codeine- and substance P-induced degranulation in a concentration-dependent manner. Ruxolitinib also significantly inhibited the production of IL-6, TNF-α and MCP-1 as induced by A23817 and substance P. Selective STAT5 inhibition with pimozide resulted in diminished degranulation and inhibition of cytokine production as induced by A23817 and substance P.

CONCLUSIONS & CLINICAL RELEVANCE

This study demonstrates that the JAK1/JAK2 inhibitor ruxolitinib can inhibit MCactivity, possibly through prevention of STAT5 activation. This renders the JAK-STAT pathway as an interesting target for therapy to release symptom burden in mastocytosis and many other MC mediator-related diseases.

Development and validation of the mastocytosis activity score

BACKGROUND

Mastocytosis is a heterogeneous disease characterized by a clonal expansion of mast cells in various organs. The vast majority of patients suffer from signs and symptoms caused by mediator release from mast cells. Although the disease burden is high, there is currently no specific and validated instrument to measure and monitor signs and symptoms in patients with mastocytosis.

OBJECTIVE

To develop and validate a disease-specific tool to measure and monitor the activity of signs and symptoms in patients with mastocytosis, the Mastocytosis Activity Score (MAS).

METHODS

Nineteen potential MAS items were developed in a combined approach consisting of semi-structured patient interviews, expert input and literature research. Item selection was performed by impact analysis with 76 patients followed by a review for face validity. The resulting MAS was tested for validity, reliability and influence factors. In parallel, a US American English version of the MAS was developed.

RESULTS

A total of 68 mastocytosis patients took part in the MAS validation study. The final 9-item MAS was found to have a three-domain structure ("skin," "gastrointestinal tract" and "other"), a valid total score and an excellent test-retest reliability. Multiple regression analysis revealed that disease duration, age or gender is not a significant determinant of the MAS results.

CONCLUSIONS

The MAS is a disease-specific, valid and reliable patient-reported outcome measure for adult patients with cutaneous and indolent systemic mastocytosis. It may serve as a valuable tool to measure and monitor mastocytosis activity, both, in clinical trials and in routine care.

Nonclonal Mast Cell Activation Syndrome: A Growing Body of Evidence

Patients who present with typical features of mast cell activation with laboratory confirmation and without evidence of a clonal mast cell disorder or other medical condition should be initiated on medical treatment to block mast cells and their mediators. If a major response is achieved, a diagnosis of nonclonal mast cell activation syndrome (NC-MCAS) is likely and treatment should be optimized, including management of any associated conditions. In this review, the latest evidence with regard to the diagnosis and treatment of NC-MCAS is presented.

Postural orthostatic tachycardia syndrome and the potential role of mast cell activation

Though a sizeable amount of data connects mast cell activity to the neurologic system, less is known about the true clinical implications of this relationship. Even less is understood about treatment strategies in those with both allergic and neurologic complaints. This is particularly true in postural orthostatic tachycardia syndrome (POTS), a common type of dysautonomia, where patients are burdened by symptoms of orthostatic cerebral hypoperfusion and several other comorbidities that are likely influenced by autonomic tone. Some patients describe characteristic allergic symptoms, in the absence of typical IgE mediated triggers, and also improvement with traditional mast cell directed medications. Further work is necessary to determine whether these anecdotal observations are valid. The answer to this question will likely be addressed as the mechanisms of POTS are better characterized, which may include a phenotype with distinct mast cell involvement.

Immunoregulatory effect of mast cells influenced by microbes in neurodegenerative diseases

When related to central nervous system (CNS) health and disease, brain mast cells (MCs) can be a source of either beneficial or deleterious signals acting on neural cells. We review the current state of knowledge about molecular interactions between MCs and glia in neurodegenerative diseases such as Multiple Sclerosis, Alzheimer's disease, Amyotrophic Lateral Sclerosis, Parkinson's disease, Epilepsy. We also discuss the influence on MC actions evoked by the host microbiota, which has a profound effect on the host immune system, inducing important consequences in neurodegenerative disorders. Gut dysbiosis, reduced intestinal motility and increased intestinal permeability, that allow bacterial products to circulate and pass through the blood-brain barrier, are associated with neurodegenerative disease. There are differences between the microbiota of neurologic patients and healthy controls. Distinguishing between cause and effect is a challenging task, and the molecular mechanisms whereby remote gut microbiota can alter the brain have not been fully elucidated. Nevertheless, modulation of the microbiota and MC activation have been shown to promote neuroprotection. We review this new information contributing to a greater understanding of MC-microbiota-neural cells interactions modulating the brain, behavior and neurodegenerative processes.

Neuroendocrinology of mast cells: Challenges and controversies

Mast cells (MC) are hemotopoietically derived tissue immune cells that are ubiquitous in the body, including neuroendocrine organs such as the hypothalamus, pineal, pituitary, ovaries, pancreas and uterus where their action is not well understood. Mast cells have historically been associated with allergies because of their rich content of histamine and tryptase, but more recently with regulation of immunity and inflammation due to their synthesis and release of numerous cytokines and chemokines. Mast cells are located perivascularly and express numerous receptors for diverse ligands such as allergens, pathogens, neurotransmitters, neuropeptides and hormones including acetylcholine, calcitonin gene-related peptide (CGRP), corticosteroids, corticotropin-releasing hormone (CRH), β-endorphin, epinephrine, 17β-oestradiol, gonadotrophins, hemokinin-A (HKA), leptin, melatonin, neurotensin (NT), parathyroid hormone (PTH), substance P (SP) and vasoactive intestinal peptide (VIP). Moreover, MC can synthesize and release most of their neurohormonal triggers, including adrenocorticotropin hormone (ACTH), CRH, endorphins, HKA, leptin, melatonin, NT, SP and VIP. Animal experiments have shown that diencephalic MC increase in number during courting in doves, while stimulation of brain and nasal MC leads to activation of the hypothalamic-pituitary-adrenal (HPA) axis. Recent evidence indicates that MC reactivity exhibits diurnal variations, and it is interesting that melatonin appears to regulate MC secretion. However, the way MC change their phenotype or secrete specific molecules selectively at different pathophysiological settings still remains unknown. Mast cells developed over 500 million years ago and may have served as the original prototype neuroimmunoendocrine cell and then evolved into a master regulator of such interactions, especially as most of the known diseases involve neuroinflammation that worsens with stress.

Characterization of Mast Cell Activation Syndrome

BACKGROUND

Mast cell activation syndrome (MCAS), a recently recognized nonneoplastic mast cell disease driving chronic multisystem inflammation and allergy, appears prevalent and thus important. We report the first systematic characterization of a large MCAS population.

METHOD

Demographics, comorbidities, symptoms, family histories, physical examination and laboratory findings were reviewed in 298 retrospective and 115 prospective patients with MCAS. Blood samples from prospective subjects were examined by flow cytometry for clonal mast cell disease and tested for cytokines potentially driving the monocytosis frequent in MCAS.

RESULTS

Demographically, white females dominated. Median ages at symptom onset and diagnosis were 9 and 49 years, respectively (range: 0-88 and 16-92, respectively) and median time from symptom onset to diagnosis was 30 years (range: 1-85). Median numbers of comorbidities, symptoms, and family medical issues were 11, 20, and 4, respectively (range: 1-66, 2-84, and 0-33, respectively). Gastroesophageal reflux, fatigue and dermatographism were the most common comorbidity, symptom and examination finding. Abnormalities in routine laboratories were common and diverse but typically modest. The most useful diagnostic markers were heparin, prostaglandin D2, histamine and chromogranin A. Flow cytometric and cytokine assessments were unhelpful.

CONCLUSIONS

Our study highlights MCAS׳s morbidity burden and challenging heterogeneity. Recognition is important given good survival and treatment prospects.

Masitinib for treatment of severely symptomatic indolent systemic mastocytosis: a randomised, placebo-controlled, phase 3 study

BACKGROUND

Indolent systemic mastocytosis, including the subvariant of smouldering systemic mastocytosis, is a lifelong condition associated with reduced quality of life. Masitinib inhibits KIT and LYN kinases that are involved in indolent systemic mastocytosis pathogenesis. We aimed to assess safety and efficacy of masitinib versus placebo in severely symptomatic patients who were unresponsive to optimal symptomatic treatments.

METHODS

In this randomised, double-blind, placebo-controlled, phase 3 study, we enrolled adults (aged 18-75 years) with indolent or smouldering systemic mastocytosis, according to WHO classification or documented mastocytosis based on histological criteria, at 50 centres in 15 countries. We excluded patients with cutaneous or non-severe systemic mastocytosis after a protocol amendment. Patients were centrally randomised (1:1) to receive either oral masitinib (6 mg/kg per day over 24 weeks with possible extension) or matched placebo with minimisation according to severe symptoms. The primary endpoint was cumulative response (≥75% improvement from baseline within weeks 8-24) in at least one severe baseline symptom from the following: pruritus score of 9 or more, eight or more flushes per week, Hamilton Rating Scale for Depression of 19 or more, or Fatigue Impact Scale of 75 or more. We assessed treatment effect using repeated measures methodology for rare diseases via the generalised estimating equation model in a modified intention-to-treat population, including all participants assigned to treatment minus those who withdrew due to a non-treatment-related cause. We assessed safety in all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT00814073.

FINDINGS

Between Feb 19, 2009, and July 15, 2015, 135 patients were randomly assigned to masitinib (n=71) or placebo (n=64). By 24 weeks, masitinib was associated with a cumulative response of 18·7% in the primary endpoint (122·6 responses of 656·5 possible responses [weighted generalised estimating equation]) compared with 7·4% for placebo (48·9 of 656·5; difference 11·3%; odds ratio 3·6; 95% CI 1·2-10·8; p=0·0076). Frequent severe adverse events (>4% difference from placebo) were diarrhoea (eight [11%] of 70 in the masitinib group vs one [2%] of 63 in the placebo group), rash (four [6%] vs none), and asthenia (four [6%] vs one [2%]). The most frequent serious adverse events were diarrhoea (three patients [4%] vs one [2%]) and urticaria (two [3%] vs none), and no life-threatening toxicities occurred. One patient in the placebo group died (unrelated to study treatment).

INTERPRETATION

These study findings indicate that masitinib is an effective and well tolerated agent for the treatment of severely symptomatic indolent or smouldering systemic mastocytosis.

FUNDING

AB Science (Paris, France).

Patient-reported disease-specific quality-of-life and symptom severity in systemic mastocytosis

BACKGROUND

Presently, no validated data exist on symptom severity and disease-specific quality-of-life (QoL) for patients with mastocytosis. Simultaneously, clinical trials and drug application processes increasingly mandate reporting patients' perspectives on symptoms and QoL. We report on the development and validation of the mastocytosis quality-of-life questionnaire (MQLQ) and the mastocytosis symptom assessment form (MSAF).

METHODS

Both outcome measures were developed in a standardized stepwise method, starting with the identification of items in focus groups (n = 12), item reduction and subsequent cross-sectional validation in a 63% female cohort of 164 adult patients with indolent systemic mastocytosis.

RESULTS

The MSAF reveals that fatigue is the severest mastocytosis symptom while the MQLQ indicates that fear of anaphylaxis mostly impacts QoL. Cross-sectional validity was assessed by correlating both individual domains and the total scores of the MQLQ and MSAF with independent measures of mastocytosis. The total scores of both the MQLQ (P < 0.001; Spearman's r: 0.568) and the MSAF (P < 0.001; Spearman's r: 0.559) correlated significantly with the consensus on physician-scored mediator symptoms. The MQLQ domains displayed a high internal consistency (Cronbach's alpha: 0.841-0.958) and the domains 'bones', 'skin symptoms' and 'anaphylaxis' differed significantly between patients with and without osteoporosis, urticaria pigmentosa or anaphylaxis, respectively (P < 0.001).

CONCLUSIONS

The MQLQ is the first disease-specific QoL questionnaire for mastocytosis and is complemented by the MSAF, a short and convenient symptom scoring form. Both patient-reported outcome measures are valid, reliable and discriminate between patients with different disease characteristics, making them useful instruments for clinical research.

Mast cell activation disease and the modern epidemic of chronic inflammatory disease

A large and growing portion of the human population, especially in developed countries, suffers 1 or more chronic, often quite burdensome ailments which either are overtly inflammatory in nature or are suspected to be of inflammatory origin, but for which investigations to date have failed to identify specific causes, let alone unifying mechanisms underlying the multiple such ailments that often afflict such patients. Relatively recently described as a non-neoplastic cousin of the rare hematologic disease mastocytosis, mast cell (MC) activation syndrome-suspected to be of greatly heterogeneous, complex acquired clonality in many cases-is a potential underlying/unifying explanation for a diverse assortment of inflammatory ailments. A brief review of MC biology and how aberrant primary MC activation might lead to such a vast range of illness is presented.

Cardiovascular symptoms in patients with systemic mast cell activation disease

Traditionally, mast cell activation disease (MCAD) has been considered as just one rare (neoplastic) disease, mastocytosis, focused on the mast cell (MC) mediators tryptase and histamine and the suggestive, blatant symptoms of flushing and anaphylaxis. Recently another form of MCAD, the MC activation syndrome, has been recognized featuring inappropriate MC activation with little to no neoplasia and likely much more heterogeneously clonal and far more prevalent than mastocytosis. Increasing expertise and appreciation has been established for the truly very large menagerie of MC mediators and their complex patterns of release, engendering complex, nebulous presentations of chronic and acute illness best characterized as multisystem polymorbidity of generally inflammatory ± allergic theme. We describe the pathogenesis of MCAD with a particular focus on clinical cardiovascular symptoms and the therapeutic options for MC mediator-induced cardiovascular symptoms.

Mastocytosis in adulthood and neuropsychiatric disorders

Patients with mastocytosis can display various disabling general and neuropsychological symptoms among one third of them, including general signs such as fatigue and musculoskeletal pain, which can have a major impact on quality of life. Neurological symptoms are less frequent and mainly consist of acute or chronic headache (35%), rarely syncopes (5%), acute onset back pain (4%), and in a few cases, clinical and radiological symptoms resembling or allowing the diagnosis of multiple sclerosis (1.3%). Headaches are associated with symptoms related to mast cell activation syndrome (flushes, prurit, and so forth) and more frequently present as migraine (37.5%), with often aura (66%). Depression-anxiety like symptoms can occur in 40% to 60% of the patients and cognitive impairment is not rare (38.6%). The pathophysiology of these symptoms could be linked to tissular mast cell infiltration or to mast cell mediators release or both. The tryptophan metabolism could be involved in mast cell-induced neuroinflammation through indoleamine-2,3-dioxygenase activation. Treatments targeting mast cell may be useful to target neuropsychological features associated with mastocytosis, including tyrosine kinase inhibitors.

Development and validation of the mastocytosis quality of life questionnaire: MC-QoL

BACKGROUND

Mastocytosis is a heterogeneous disease characterized by a clonal expansion of mast cells in various organs. The vast majority of patients affected suffer from signs and symptoms caused by mediator release from mast cells. Although the disease burden is high, there is currently no specific instrument to measure health-related quality of life (HRQoL) impairment in patients with mastocytosis.

OBJECTIVE

The aim of this study was to develop and validate a disease-specific tool to assess HRQoL impairment in patients with cutaneous and indolent systemic mastocytosis, the Mastocytosis Quality of Life Questionnaire (MC-QoL).

METHODS

Sixty-two potential MC-QoL items were developed in a combined approach consisting of semi-structured patient interviews, expert input and literature research. Item selection was performed by impact analysis with 76 patients and a final review for face validity. The resulting MC-QoL was tested for validity, reliability and influence factors. In parallel, an US American-English version of the MC-QoL was developed.

RESULTS

A total of 158 patients (41 CM, 41 MIS and 76 ISM) took part in the MC-QoL validation study. The final 27-item questionnaire was found to have a four-domain structure ('symptoms', 'emotions', 'social life/functioning' and 'skin'), a valid total score and an excellent test-retest reliability. Multiple regression analysis revealed disease duration, but not age, gender or skin involvement to be a significant determinant of HRQoL impairment in mastocytosis.

CONCLUSIONS

The MC-QoL is the first disease-specific HRQoL questionnaire for adult patients with cutaneous and indolent systemic mastocytosis. This short, validated and reliable instrument will serve as a valuable tool in future clinical studies and in routine patient care.

Systemic mastocytosis: A cohort study on clinical characteristics of 136 patients in a large tertiary centre

BACKGROUND

Systemic mastocytosis (SM) is a rare heterogeneous disease which is characterized by the aberrant proliferation of mast cells. It can be divided into various subtypes with different phenotypes and prognoses. Here, we report on the clinical characteristics of 136 SM patients.

METHODS

A retrospective cohort study was conducted from January 2009 to September 2014 in a large tertiary centre in The Netherlands. We included all patients who fulfilled WHO criteria for SM. Data were collected from electronic patient files.

RESULTS

A total of 124 patients had indolent SM (ISM) (91.2%), 7 had aggressive SM (ASM) (5.1%) and 5 had SM with associated hematological non-mast cell lineage disease (SM-AHNMD) (3.7%). There was no progression from ISM to advanced SM subtypes, but 1 patient with ASM developed chronic myelocytic leukemia 2years after diagnosis. The average time to diagnosis for the whole population was 8.1years (range, 0-49years). The most frequent triggers for work-up-skin involvement, anaphylaxis and osteoporosis-were characterized by an interval to diagnosis of 10.9, 2.9 and 7.5years, respectively. A total of 32 patients (23.5%) had a serum tryptase levels below the cutoff value of 20ng/mL at the time of diagnosis, but these patients did not have significant differences in clinical phenotype.

CONCLUSIONS

SM comprises a wide spectrum of signs and symptoms and its often atypical presentation can delay the establishment of the diagnosis substantially. Skin involvement, anaphylaxis and unexplained osteoporosis should trigger analysis for mastocytosis. A normal serum tryptase does not exclude the diagnosis of SM.

Roads Less Traveled: Sexual Dimorphism and Mast Cell Contributions to Migraine Pathology

Migraine is a common, little understood, and debilitating disease. It is much more prominent in women than in men (~2/3 are women) but the reasons for female preponderance are not clear. Migraineurs frequently experience severe comorbidities, such as allergies, depression, irritable bowel syndrome, and others; many of the comorbidities are more common in females. Current treatments for migraine are not gender specific, and rarely are migraine and its comorbidities considered and treated by the same specialist. Thus, migraine treatments represent a huge unmet medical need, which will only be addressed with greater understanding of its underlying pathophysiology. We discuss the current knowledge about sex differences in migraine and its comorbidities, and focus on the potential role of mast cells (MCs) in both. Sex-based differences in pain recognition and drug responses, fluid balance, and the blood–brain barrier are recognized but their impact on migraine is not well studied. Furthermore, MCs are well recognized for their prominent role in allergies but much less is known about their contributions to pain pathways in general and migraine specifically. MC-neuron bidirectional communication uniquely positions these cells as potential initiators and/or perpetuators of pain. MCs can secrete nociceptor sensitizing and activating agents, such as serotonin, prostaglandins, histamine, and proteolytic enzymes that can also activate the pain-mediating transient receptor potential vanilloid channels. MCs express receptors for both estrogen and progesterone that induce degranulation upon binding. Furthermore, environmental estrogens, such as Bisphenol A, activate MCs in preclinical models but their impact on pain pathways or migraine is understudied. We hope that this discussion will encourage scientists and physicians alike to bridge the knowledge gaps linking sex, MCs, and migraine to develop better, more comprehensive treatments for migraine patients.

The Role of TRAF4 and B3GAT1 Gene Expression in the Food Hypersensitivity and Insect Venom Allergy in Mastocytosis

Mastocytosis is an uncommon disease classified as a myeloproliferative neoplasm, however, its symptoms are broad and place patients at crossroads between dermatology, hematology and allergology. Patients with mastocytosis often suffer from symptoms resulting from the activation and release of mediators from the mast cells, such as generalized itching, redness, headache, abdominal cramps, diarrhea, bone pain or arthritis, hypotension and shock. The possible severe, fatal or near fatal reactions caused by food hypersensitivity are reasons for the research focused on marker identification. The aim of the study was to analyse the gene expression differences in mastocytosis patients with and without food and drug hypersensitivity and insect venom allergy (IVA). A total of 57 Caucasian patients with mastocytosis were studied [median age 41.8; range 18–77 years; 15 (26.3 %) males and 42 (73.7 %) females]. Quantitative RT-PCRs of 11 genes plus ribosomal 18S RNA were run. Symptoms of food hypersensitivity were found in 12 patients (21 %), including 3 patients (13 %) with cutaneous mastocytosis (CM), and 9 (28 %) with indolent systemic mastocytosis (ISM). IVA was confirmed in 13 patients (22.8 %) including 6 patients (10.5 %) with CM, and 7 patients (12.3 %) with ISM. Drug hypersensitivity was diagnosed in 10 patients (17.5 %). Significant differences in the gene expression were found for TRAF4 (p = 0.008) in the comparison of the mastocytosis patients with and without concomitant food hypersensitivity. Furthermore significant differences were found in gene expression for B3GAT1 (p = 0.003) in patients with IVA compared to patients without insect sting anaphylaxis in the medical history. The expression of studied genes did not differ according to the presence of drug hypersensitivity. The TRAF4 expression was higher in mastocytosis patients with food hypersensitivity in their medical history, the B3GAT1 expression was lower in mastocytosis patients with IVA in history.

Psychosocial impact of mast cell disorders: Pilot investigation of a rare and understudied disease

Mast cell disorders are rare, chronic diseases involving unpredictable physical symptoms ranging in severity, duration, and frequency. Almost two-thirds of participants with these disorders ( n = 180) experienced clinically meaningful depressive symptoms. Depressed mood was associated with somatic symptomatology, poorer quality of life, lower resilience, and indirectly with ways of coping. Newly developed measures for this population performed psychometrically well. There was no gender difference in depression but women reported greater use of several ways of coping, greater disease-related distress, poorer quality of life, and more symptoms. Results underscore the need for further research and development of effective psychosocial interventions for this population.

Genitourinary mast cells and survival

Mast cells (MCs) are ubiquitous in the body, but they have historically been associated with allergies, and most recently with regulation of immunity and inflammation. However, it remains a puzzle why so many MCs are located in the diencephalon, which regulates emotions and in the genitourinary tract, including the bladder, prostate, penis, vagina and uterus that hardly ever get allergic reactions. A number of papers have reported that MCs have estrogen, gonadotropin and corticotropin-releasing hormone (CRH) receptors. Moreover, animal experiments have shown that diencephalic MCs increase in number during courting in doves. We had reported that allergic stimulation of nasal MCs leads to hypothalamic-pituitary adrenal (HPA) activation. Interestingly, anecdotal information indicates that female patients with mastocytosis or mast cell activation syndrome may have increased libido. Preliminary evidence also suggests that MCs may have olfactory receptors. MCs may, therefore, have been retained phylogenetically not only to “smell danger”, but to promote survival and procreation.

Neuropeptides CRH, SP, HK-1, and Inflammatory Cytokines IL-6 and TNF Are Increased in Serum of Patients with Fibromyalgia Syndrome, Implicating Mast Cells

Fibromyalgia syndrome (FMS) is a chronic, idiopathic condition of widespread musculoskeletal pain affecting more women than men. Even though clinical studies have provided evidence of altered central pain pathways, the lack of definitive pathogenesis or reliable objective markers has hampered development of effective treatments. Here we report that the neuropeptides corticotropin-releasing hormone (CRH), substance P (SP), and SP-structurally-related hemokinin-1 (HK-1) were significantly (P = 0.026, P < 0.0001, and P = 0.002, respectively) elevated (0.82 ± 0.57 ng/ml, 0.39 ± 0.18 ng/ml, and 7.98 ± 3.12 ng/ml, respectively) in the serum of patients with FMS compared with healthy controls (0.49 ± 0.26 ng/ml, 0.12 ± 0.1 ng/ml, and 5.71 ± 1.08 ng/ml, respectively). Moreover, SP and HK-1 levels were positively correlated (Pearson r = 0.45, P = 0.002) in FMS. The serum concentrations of the inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF) were also significantly (P = 0.029 and P = 0.006, respectively) higher (2.97 ± 2.35 pg/ml and 0.92 ± 0.31 pg/ml, respectively) in the FMS group compared with healthy subjects (1.79 ± 0.62 pg/ml and 0.69 ± 0.16 pg/ml, respectively). In contrast, serum IL-31 and IL-33 levels were significantly lower (P = 0.0001 and P = 0.044, respectively) in the FMS patients (849.5 ± 1005 pg/ml and 923.2 ± 1284 pg/ml, respectively) in comparison with healthy controls (1281 ± 806.4 pg/ml and 3149 ± 4073 pg/ml, respectively). FMS serum levels of neurotensin were not different from controls. We had previously shown that CRH and SP stimulate IL-6 and TNF release from mast cells (MCs). Our current results indicate that neuropeptides could stimulate MCs to secrete inflammatory cytokines that contribute importantly to the symptoms of FMS. Treatment directed at preventing the secretion or antagonizing these elevated neuroimmune markers, both centrally and peripherally, may prove to be useful in the management of FMS.

Often seen, rarely recognized: mast cell activation disease--a guide to diagnosis and therapeutic options

Mast cell (MC) disease has long been thought to be just the rare disease of mastocytosis (in various forms, principally cutaneous and systemic), with aberrant MC mediator release at symptomatic levels due to neoplastic MC proliferation. Recent discoveries now show a new view is in order, with mastocytosis capping a metaphorical iceberg now called "MC activation disease" (MCAD, i.e. disease principally manifesting inappropriate MC activation), with the bulk of the iceberg being the recently recognized "MC activation syndrome" (MCAS), featuring inappropriate MC activation to symptomatic levels with little to no inappropriate MC proliferation. Given increasing appreciation of a great menagerie of mutations in MC regulatory elements in mastocytosis and MCAS, the great heterogeneity of MCAD's clinical presentation is unsurprising. Most MCAD patients present with decades of chronic multisystem polymorbidity generally of an inflammatory ± allergic theme. Preliminary epidemiologic investigation suggests MCAD, while often misrecognized, may be substantially prevalent, making it increasingly important that practitioners of all stripes learn how to recognize its more common forms such as MCAS. We review the diagnostically challenging presentation of MCAD (with an emphasis on MCAS) and current thoughts regarding its biology, epidemiology, natural history, diagnostic evaluation, and treatment.

Mast cell activation syndromes presenting as anaphylaxis

Anaphylaxis results from severe systemic mast cell activation. In addition to IgE-mediated and physical triggers, it may occur with a clonal mast cell disease and in an idiopathic fashion without clear provoking factors. Disorders of mast cell activation are classified into primary (clonal), secondary, and idiopathic. Mast cell activation syndrome (MCAS) is a multisystem disorder characterized by objective documentation of elevated mast cell mediators during attacks and a favorable response to antimediator therapy. It should be considered in the differential diagnosis of patients presenting with recurrent anaphylaxis without a clear cause. This article discusses the diagnosis of MCAS.

Mast Cell-Mediated Mechanisms of Nociception

Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner.

Mast cells, brain inflammation and autism

Increasing evidence indicates that brain inflammation is involved in the pathogenesis of neuropsychiatric diseases. Mast cells (MCs) are located perivascularly close to neurons and microglia, primarily in the leptomeninges, thalamus, hypothalamus and especially the median eminence. Corticotropin-releasing factor (CRF) is secreted from the hypothalamus under stress and, together with neurotensin (NT), can stimulate brain MCs to release inflammatory and neurotoxic mediators that disrupt the blood-brain barrier (BBB), stimulate microglia and cause focal inflammation. CRF and NT synergistically stimulate MCs and increase vascular permeability; these peptides can also induce each other׳s surface receptors on MCs leading to autocrine and paracrine effects. As a result, brain MCs may be involved in the pathogenesis of "brain fog," headaches, and autism spectrum disorders (ASDs), which worsen with stress. CRF and NT are significantly increased in serum of ASD children compared to normotypic controls further strengthening their role in the pathogenesis of autism. There are no clinically affective treatments for the core symptoms of ASDs, but pilot clinical trials using natural-antioxidant and anti-inflammatory molecules reported statistically significant benefit.

Mast Cell Activation Disease and Microbiotic Interactions

PURPOSE

This article reviews the diagnostically challenging presentation of mast cell activation disease (MCAD) and current thoughts regarding interactions between microbiota and MCs.

METHODS

A search for all studies on interactions between mast cells, mast cell activation disease, and microbiota published on pubmed.gov and scholar.google.com between 1960 and 2015 was conducted using the search terms mast cell, mastocyte, mastocytosis, mast cell activation, mast cell activation disease, mast cell activation syndrome, microbiome, microbiota. A manual review of the references from identified studies was also conducted. Studies were excluded if they were not accessible electronically or by interlibrary loan.

FINDINGS

Research increasingly is revealing essential involvement of MCs in normal human biology and in human disease. Via many methods, normal MCs-present sparsely in every tissue-sense their environment and reactively exert influences that, directly and indirectly, locally and remotely, improve health. The dysfunctional MCs of the "iceberg" of MCAD, on the other hand, sense abnormally, react abnormally, activate constitutively, and sometimes (in mastocytosis, the "tip" of the MCAD iceberg) even proliferate neoplastically. MCAD causes chronic multisystem illness generally, but not necessarily, of an inflammatory ± allergic theme and with great variability in behavior among patients and within any patient over time. Furthermore, the range of signals to which MCs respond and react include signals from the body's microbiota, and regardless of whether an MCAD patient has clonal mastocytosis or the bulk of the iceberg now known as MC activation syndrome (also suspected to be clonal but without significant MC proliferation), dysfunctional MCs interact as dysfunctionally with those microbiota as they interact with other human tissues, potentially leading to many adverse consequences.

IMPLICATIONS

Interactions between microbiota and MCs are complex at baseline. The potential for both pathology and benefit may be amplified when compositionally variant microbiota interact with aberrant MCs in various types of MCAD. More research is needed to better understand and leverage these interactions.

Systemic mastocytosis presenting with gastrointestinal, bone and skin involvement

Ultrasonography (US) is often the first imaging study performed in patient with abdominal pain or vague symptoms related to the gastrointestinal tract. To this end, it has been demonstrated that transabdominal sonography achieves good to excellent results in potential bowel disorders; especially, if ultrasonography findings are framed in the context of clinical information. Systemic mastocytosis is not a common disease and it usually involves skin, gastrointestinal tract and bone. It results from a clonal neoplastic proliferation of abnormal mast cells and clinically it can ranges from 'asymptomatic' with normal life expectancy to 'highly aggressive'. Symptoms are caused by the release of mast cells mediators, such as histamine, and by the increase bulk of mast cells in the tissue. We present herein a case of systemic mastocytosis presenting with abdominal symptomatology due to thickened colonic involvement showed by US associated with bone and skin involvement.