Histological characterization of liver involvement in systemic mastocytosis.

Background And Aims: Systemic mastocytosis (SM) is characterized by the accumulation of atypical mast cells (MCs) in organs. Liver histology of SM has been marginally described and accurate histological classification is critical, given the consequences of aggressive SM diagnosis. We aimed to describe the histological features associated with liver SM using updated tools.

The Prevalence Of Osteoporosis Is Low in Adult Cutaneous Mastocytosis Patients.

Background: Systemic mastocytosis (SM) is a clonal disorder of mast cells (MCs) frequently associated with vertebral osteoporosis (OP) and subsequent vertebral fractures (VFs). The natural history of this OP remains unclear. Importantly, we do not know whether OP represents an early event triggered alongside MC abnormalities, and whether MC clonality is sufficient to trigger osteoporosis.

Pathophysiologic implications of elevated prevalence of hereditary alpha-tryptasemia in all mastocytosis subtypes.

Background: Mastocytosis and monoclonal mast cell (MC) activation syndrome (MMAS) are heterogeneous conditions characterized by the accumulation of atypical MCs. Despite the recurrent involvement of KIT mutations, the pathophysiologic origin of mastocytosis and MMAS is unclear. Although hereditary α-tryptasemia (HαT, related to TPSAB1 gene duplication) is abnormally frequent in these diseases, it is not known whether the association is coincidental or causal.

3D deconvolution of human skin immune architecture with Multiplex Annotated Tissue Imaging System.

Routine clinical assays, such as conventional immunohistochemistry, often fail to resolve the regional heterogeneity of complex inflammatory skin conditions. We introduce MANTIS (Multiplex Annotated Tissue Imaging System), a flexible analytic pipeline compatible with routine practice, specifically designed for spatially resolved immune phenotyping of the skin in experimental or clinical samples. On the basis of phenotype attribution matrices coupled to α-shape algorithms, MANTIS projects a representative digital immune landscape while enabling automated detection of major inflammatory clusters and concomitant single-cell data quantification of biomarkers.

Effective Anti-SARS-CoV-2 Immune Response in Patients With Clonal Mast Cell Disorders.

Background: Mast cells are key players in innate immunity and the T2 adaptive immune response. The latter counterbalances the T1 response, which is critical for antiviral immunity. Clonal mast cell activation disorders (cMCADs, such as mastocytosis and clonal mast cell activation syndrome) are characterized by abnormal mast cell accumulation and/or activation.

Neuropsychiatric, cognitive and sexual impairment in mastocytosis patients.

Background: Mastocytosis is a rare disease characterised by the accumulation and/or proliferation of abnormal mast cells (MCs) in one or several organs. It may present with a number of different symptoms that involve various organ systems. The current study aims to assess the prevalence of MC mediator-related symptoms in a cohort of mastocytosis patients with a specific focus on neurological, psychiatric, cognitive and sexual symptoms.

Omalizumab in the treatment of adult patients with mastocytosis: A systematic review.

BACKGROUND: Mastocytosis is associated with mast cell (MC) mediator-related symptoms for which limited therapies are available. OBJECTIVE: Our aim was to assess the efficacy and safety of omalizumab in the treatment of MC mediator-related symptoms in adult patients with mastocytosis. RESULTS: We identified one multi-centre retrospective cohort study (39 patients), one retrospective cohort study (13 patients), 4 case series and 10 case reports.

Plasma cell-directed therapies in monoclonal gammopathy-associated scleromyxedema.

Scleromyxedema is a rare skin and systemic mucinosis that is usually associated with monoclonal gammopathy (MG). In this French multicenter retrospective study of 33 patients, we investigated the clinical and therapeutic features of MG-associated scleromyxedema. Skin molecular signatures were analyzed using a transcriptomic approach.

Omalizumab Therapy for Mast Cell-Mediator Symptoms in Patients with ISM, CM, MMAS, and MCAS.

Background: Patients with mast cell diseases may suffer from various distressing symptoms, which can be insufficiently controlled with available therapies, severely affecting their quality of life. There is a need for new and safe treatment options for these patients.

Objectives: We aimed to evaluate safety and efficacy of omalizumab administration in patients with a symptomatic mast cell disorder.