Health-Related Quality of Life and Influencing Factors in Adults with Nonadvanced Mastocytosis-A Cross-Sectional Study and Qualitative Approach

Prevalence of hypersensitivity reactions in various forms of mastocytosis: A pilot study of 2485 adult patients with mastocytosis collected in the ECNM registry

BACKGROUND

Hypersensitivity reactions (HR) are common in mastocytosis. However, little is known about triggers and risk factors. The registry of the European Competence Network on Mastocytosis (ECNM) enables reliable studies in a larger cohort of mastocytosis patients. We assessed prevalence, triggers and risk factors of HR in adults with mastocytosis in the ECNM registry.

METHODS

Data were collected in 27 ECNM centers. We analyzed potential triggers (Hymenoptera venoms, food, drug, inhalant and others) and risk factors at diagnosis and during follow-up. The study group consisted of 2485 adults with mastocytosis, 1379 women (55.5%) and 1106 men (44.5%). Median age was 48.2 years (range 18-91 years).

RESULTS

Nine hundred and forty eight patients (38.1%) reported one or more HR`. Most common triggers were Hymenoptera venoms in cutaneous mastocytosis (CM) and indolent systemic mastocytosis (ISM), whereas in advanced SM (advSM), most common elicitors were drugs, including nonsteroidal anti-inflammatory agents and penicillin. In multivariate analyses, tryptase level < 90 ng/mL, <15% infiltration by mast cells in bone marrow biopsy-sections, and diagnosis of ISM were identified as independent risk factors for HR. For drug-induced HR, prominent risk factors were advSM and high tryptase levels. New reactions were observed in 4.8% of all patients during 4 years follow-up.

CONCLUSIONS

HR are mainly triggered by Hymenoptera venoms in patients with CM and ISM and by drugs in patients with advSM. Tryptase levels <90 ng/mL, mast cell bone marrow infiltration <15%, and WHO category ISM are predictors of HR. New HR occur in 4.8% of all patients within 4 years.

Hereditary Alpha Tryptasemia: Validation of a Single-Well Multiplex Digital Droplet PCR Assay in a Cohort of Symptomatic Patients

BACKGROUND

Hereditary alpha tryptasemia (HαT) has significant prevalence and potential morbidity in the general population. However, it remains largely undiagnosed in routine clinical diagnostics due to low availability of efficient assessment methods. To address this issue, we developed a reliable and efficient single-well multiplex digital droplet PCR assay.

METHODS

The assay was based on the reconstruction of the TPSAB1 gene through quantification of the ratio of α- and β-tryptase copy number variants (CNV) in a single-well measurement. We performed analytical validation by determining CNV measurement clustering around the expected copy numbers in 281 cases and determined the diagnostic accuracy of basal serum tryptase (BST) to predict HαT and HαT subtypes in 141 symptomatic patients.

RESULTS

The assay determined α- and β-tryptase CNVs with an overall accuracy, expressed as a 99% prediction interval, of 0.03 ± 0.27 copy numbers. The optimal BST cutoff level to predict HαT in symptomatic patients, who had no other explanation for relatively high tryptase levels (i.e., no diagnosis of systemic mastocytosis, myeloid neoplasm, or end-stage renal failure), was 9.2 ng/mL (sensitivity: 98.1%; specificity: 96.6%). HαT showed a linear gene-dose effect, with an average gene-dose increase of 7.5 ng/mL per extra α-tryptase gene.

CONCLUSION

Our single-well multiplex digital droplet PCR assay accurately determined HαT and could be implemented as a state-of-the-art routine diagnostic test. The assay demonstrated a strong correlation with BST and the optimal threshold for identifying HαT in symptomatic patients with unexplained high tryptase concentrations was at a BST level of 9.2 ng/mL.

Cognitive Impairment and Depression in Mastocytosis: A Synthesis of the Literature

PURPOSE OF REVIEW

Symptoms of depression and cognitive dysfunction are commonly reported in mastocytosis. The aims of this review paper are to summarize the current literature on cognitive dysfunction and depressive symptoms, elucidate some of the mechanistic pathways underlying depressive symptoms in mastocytosis, identify gaps in the literature, and offer guidance for future research in this area.

RECENT FINDINGS

The study of cognition and depression in mastocytosis is in its infancy and the methodological flaws of the current literature limit interpretability. There is preliminary evidence that some individuals with mastocytosis might experience mild deficits in memory. On average, depression symptom scores fell within the mild to moderate or sub-syndromal range. Regrettably, only one study utilized a standardized diagnostic instrument to assess major depressive disorder. The authors' tendency to inaccurately equate depressive symptoms with a diagnosis of major depressive disorder presents a notable issue. The prevalence of cognitive deficits and depression appears to be similar to other chronic illnesses. Future work needs to better characterize cognition and characterize "depression" in this population.

Challenges in the Diagnosis of Cutaneous Mastocytosis

BACKGROUND

Mastocytosis is characterized by an accumulation of clonal mast cells (MCs) in tissues such as the skin. Skin lesions in mastocytosis may be clinically subtle or heterogeneous, and giving the correct diagnosis can be difficult.

METHODS

This study compiles personal experiences together with relevant literature, discussing possible obstacles encountered in diagnosing skin involvement in mastocytosis and cutaneous mastocytosis (CM).

RESULTS

The nomenclature of the term "CM" is ambiguous. The WHO classification defines CM as mastocytosis solely present in the skin. However, the term is also used as a morphological description, e.g., in maculopapular cutaneous mastocytosis (MPCM). This is often seen in systemic, as well as cutaneous, mastocytosis. Typical CM manifestations (MPCM), including mastocytoma or diffuse cutaneous mastocytosis (DCM), all share a positive Darier's sign, and can thus be clinically recognized. Nevertheless, distinguishing monomorphic versus polymorphic MPCM may be challenging, even for experienced dermatologists. Less typical clinical presentations, such as MPCM with telangiectatic erythemas (formerly called telangiectasia macularis eruptiva perstans), confluent, nodular or xanthelasmoid variants may require a skin biopsy for histopathological confirmation. Because MC numbers in CM have a large overlap to those in healthy and inflamed skin, detailed histopathological criteria to diagnose mastocytosis in MPCM are needed and have been proposed. D816V KIT mutational analysis in tissue is helpful for confirming the diagnosis. Biomarkers allow the prediction of the course of CM into regression or evolution of the disease. Further diagnostic measures should screen for concomitant diseases, such as malignant melanoma, and for systemic involvement.

CONCLUSIONS

Whereas in typical cases the diagnosis of CM may be uncomplicated, less typical manifestations may require specific investigations for making the diagnosis and predicting its course.

Cognitive, neuropsychiatric and neurological alterations in mastocytosis: A systematic review

BACKGROUND

Mastocytosis manifests with multisystemic symptoms, often involving the nervous system. Numerous cognitive, neuropsychiatric and neurological alterations have been reported in multiple observational studies.

METHODS

We performed a qualitative systematic literature review of reported data consulting the electronic databases Medline, Scopus, Web of Science, Cochrane, and BASE until June 2023.

RESULTS

We selected 24 studies in which the majority showed that a high proportion of mastocytosis patients suffer cognitive, neuropsychiatric and neurological alterations. The most common disorders and estimated ranges of frequency observed in adults were depression (68%-75%), anxiety, high stress or irritability (27%-54%), cognitive impairment (27%-39%, primarily affecting memory skills), and headaches (55%-69%). Attention challenges and learning difficulties were reported in children at a rate of 13%, while neurodevelopmental disorders occurred at rates of 8%-12%. Frequent white abnormalities in mastocytosis patients with concomitant psychocognitive symptoms have been reported although neuroimaging studies have been performed rarely in this population.

CONCLUSION

Further studies with more comprehensive and homogeneous evaluations and neuroimaging and histological analysis should be performed for a better understanding of these manifestations. An earlier detection and proper management of these symptoms could greatly improve the quality of life of these patients.

Measuring Symptom Severity and Quality of Life in Mastocytosis

Mastocytosis is a heterogeneous disease with a wide spectrum of signs, symptoms, and concomitant disorders, such as skin lesions, anaphylaxis, osteoporosis, gastrointestinal involvement, and organomegaly. Disease specificity for frequently reported symptoms, such as fatigue, headache, anxiety, and brain fog, is poorly defined and need to be addressed in further studies. Patients with CM and non-AdvSM are mostly affected by mast cell mediator-related symptoms, whereas in AdvSM symptoms also result from organ damage, which makes their assessment challenging. In this paper we discuss approaches currently used to measure symptom burden and QoL impairment in relation to the clinical phenotype.

Mastocytosis in Pregnancy

Mastocytosis is a rare neoplastic disorder of the mast cell lineage resulting in unregulated proliferation and activation of mast cells. Symptoms worsen in about one-third of pregnant patients. Treatment focuses on management of symptoms with antimediator therapy (H1 & H2 antihistamines, glucocorticoids, and epinephrine, if required). Medication selection requires care during labor and delivery. Although it is generally considered safe to use a medication patient tolerated before, some common medications may need to be avoided or used with caution (eg, codeine, morphine, nonsteroidal antiinflammatory drugs, vancomycin) if the patient does not have any history of exposure to them.

Mast Cell Diseases in Practice and Research: Issues and Perspectives Raised by Patients and Their Recommendations to the Scientific Community and Beyond

BACKGROUND

Since 2010, patients and physicians have collaborated to understand unmet needs of patients with mast cell diseases, incorporating mastocytosis and mast cell activation disorders, which include mast cell activation syndromes.

OBJECTIVE

This Open Innovation in Science project aims to expand understanding of the needs of patients affected by mast cell diseases, and encourage global communication among patient advocacy groups, physicians, researchers, industry, and government. A major aim is to support the scientific community's efforts to improve diagnosis, management, therapy, and patients' quality of life by addressing unmet needs.

METHODS

In collaboration with mast cell disease specialists, 13 patient advocacy groups from 12 countries and regions developed lists of top patient needs. A core team of leaders from patient advocacy groups collected and analyzed the data and proposed possible actions to address patient needs.

RESULTS

Findings identified similarities and differences among participating countries in unmet needs between patients with mastocytosis and those with mast cell activation syndromes. Issues emphasized struggles relating to the nature and rarity of mast cell diseases, their impact on quality of life, the diagnostic process, access to appropriate care, more effective treatment, and the need for research.

CONCLUSIONS

Solutions vary across countries because situations differ, in particular regarding the existence of and access to centers of excellence and reference centers. Multifaceted mast cell activation syndrome barriers necessitate innovative approaches to improve access to appropriate care. The outcomes of this project should greatly support scientists and clinicians in their efforts to improve diagnosis, management, and treatment of patients with mastocytosis and mast cell activation disorders.

Health-related quality of life and health literacy in patients with systemic mastocytosis and mast cell activation syndrome

BACKGROUND

Systemic mastocytosis is a rare genetic disease characterized by aberrant proliferation and/or activation of mast cells, resulting in multi-organ, allergy-like symptoms. Mast cell activation syndrome (MCAS) is a clinically similar, but more prevalent disease with unclear etiology. In this study, the health-related quality of life (HRQOL) and health literacy of people suffering from SM and MCAS were assessed.

RESULTS

Two validated questionnaires (QLQ-C30/QLQ-INFO25) from the European Organisation for Research and Treatment of Cancer (EORTC) were used to analyze HRQOL and level of information of SM and MCAS patients. In addition, a control group without any health issues was included. Data were analyzed by ANOVA and linear regression to detect significant differences. Questionnaire data from 66 patients with MCAS (83% female, mean 44 years), 32 patients with SM (78% female, mean 53 years) and 52 healthy participants (67% female, mean 48 years) resident in Germany were analyzed. HRQOL as measured by the Global health status was significantly worse in patients suffering from MCAS or SM compared to control group. Individuals with MCAS showed a slightly, but insignificantly lower score on Global health status, and a significantly lower score with respect to role function and fatigue. Patients with the rare disease SM felt significantly better informed on their disease compared to MCAS patients. Linear regression performed separately for both groups showed a direct influence of the level of information on patients' HRQOL.

CONCLUSION

Overall, our study showed a significant negative impact on the HRQOL of both diseases, but only a small difference in quality of life and severity of symptoms between patients with MCAS and the supposedly more severe form, the rare disease SM. Our results demonstrate that the level of information patients receive impacts HRQOL, and that this is not only an issue in rare diseases, but also diseases with unclear etiology and pathology. Our data shows that even slight improvements in the patient's level of information can have a positive effect on their quality of life, further highlighting the importance of gaining more knowledge on rare and incompletely understood diseases and communicating these insights to patients.

Quality of life in patients with allergic and immunologic skin diseases: in the eye of the beholder

Allergic and immunologic skin diseases negatively impact the quality of life (QoL) of affected patients with detrimental consequences. Nonetheless, in everyday clinical practice the evaluation of QoL is often overlooked. Considering the increasing prevalence of atopic dermatitis, allergic contact dermatitis, hereditary angioedema, cutaneous mastocytosis, and urticaria, it is essential to determine the effects of allergic and immunologic skin diseases on QoL. A joint meeting (GET TOGETHER 2021) of the Italian Society of Allergology, Asthma and Clinical Immunology (SIAAIC) and the Italian Society of Allergological, Occupational and Environmental Dermatology (SIDAPA) aimed to summarize the features of the main QoL tools used in these diseases and to describe the extent of QoL impairment as well as the impact of treatments on QoL, particularly biologic therapies. The assessment of QoL in patients with allergic and immunologic skin diseases relies on generic, organ-specific and disease-specific questionnaires. While generic and organ-specific questionnaires allow comparison between different diseases, disease-specific questionnaires are designed and validated for specific cohorts: the QoL Index for Atopic Dermatitis (QoLIAD) and the Childhood Atopic Dermatitis Impact Scale (CADIS) in atopic dermatitis, the ACD-11 in allergic contact dermatitis, the Angioedema QoL Questionnaire (AE-QoL) and the Hereditary Angioedema QoL questionnaire (HAE-QoL) in hereditary angioedema, the Mastocytosis QoL Questionnaires (MCQoL e MQLQ) in cutaneous mastocytosis, and the Chronic Urticaria QoL questionnaire (CU-Q2oL) in urticaria. Among the many factors that variably contribute to QoL impairment, pruritus can represent the leading cause of patient discomfort. Biologic therapies significantly ameliorate QoL in atopic dermatitis, hereditary angioedema, mastocytosis and chronic urticaria. In general, adequate management strategies are essential for improving QoL in patients with allergic and immunologic skin diseases.

Precision Medicine in Systemic Mastocytosis

Mastocytosis is a rare hematological neoplasm characterized by the proliferation of abnormal clonal mast cells (MCs) in different cutaneous and extracutaneous organs. Its diagnosis is based on well-defined major and minor criteria, including the pathognomonic dense infiltrate of MCs detected in bone marrow (BM), elevated serum tryptase level, abnormal MCs CD25 expression, and the identification of KIT D816V mutation. The World Health Organization (WHO) classification subdivides mastocytosis into a cutaneous form (CM) and five systemic variants (SM), namely indolent/smoldering (ISM/SSM) and advanced SM (AdvSM) including aggressive SM (ASM), SM associated to hematological neoplasms (SM-AHN), and mast cell leukemia (MCL). More than 80% of patients with SM carry a somatic point mutation of KIT at codon 816, which may be targeted by kinase inhibitors. The presence of additional somatic mutations detected by next generation sequencing analysis may impact prognosis and drive treatment strategy, which ranges from symptomatic drugs in indolent forms to kinase-inhibitors active on KIT. Allogeneic stem cell transplant (SCT) may be considered in selected SM cases. Here, we review the clinical, diagnostic, and therapeutic issues of SM, with special emphasis on the translational implications of SM genetics for a precision medicine approach in clinical practice.