Gastrointestinal involvement and manifestations in systemic mastocytosis

Mast Cell Esophagitis: A Novel Entity in Patients with Unexplained Esophageal Symptoms

It is not known whether esophageal mast cells may be a cause of unexplained esophageal symptoms. We aimed to determine the prevalence of esophageal mastocytosis in patients without other underlying causes of symptoms and assess the relationship between symptoms and mast cells. In this retrospective study, we identified adults with esophageal symptoms, a normal endoscopy, normal esophageal biopsies, and no definitive diagnosis during clinical evaluation. We quantified mast cell density (mast cells/mm2) in archived esophageal biopsies using tryptase immunohistochemistry, and compared mast cell levels by clinical features and physiologic testing. In the 87 patients identified (mean age 37, 72% female, 63% white, 92% non-Hispanic), common symptoms were dysphagia (76%), heartburn (71%), and chest pain (25%). Overall, the mean esophageal epithelial mast cell count was 83.0 ± 51.8 mast cells/mm2; 60% of patients had ≥ 60 mast/mm2, and 17% had ≥ 120 masts/mm2. There were no differences in mast cell counts by type of esophageal testing. Mast cell levels did not differ significantly by type of symptoms, atopic status, medications, smoking status, or alcohol use. There were also no major differences in clinical characteristics by mast cell quartiles or thresholds. In conclusion, esophageal mast cell infiltration was common in patients with symptoms unexplained by prior testing, and levels were higher than previously published values for patients with no underlying esophageal condition. Mast cell esophagitis could be a novel cause of unexplained esophageal symptoms in a subset of patients, though it reamins to be determined if such patients benefit from mast cell-targeted treatment.

Mast cells are at the interface between the external environment and the inner organism

Mast cells localized at the level of the mucosal barrier in the skin, lung, and gastrointestinal tract, intervene in the modulation of the function of the epithelial cells and are involved in innate and adaptive defensive responses. In this context, mast cells intervene in the recognition and clearance of microbial pathogens. This mini-review article discusses the role of mast cells in these barrier systems.

Acute Appendicitis as the First and the Only Presentation of Systemic Mastocytosis

Systemic mastocytosis is a rare myeloproliferative disorder characterized by abnormal accumulation of mast cells in a variety of organs. When affecting the gastrointestinal tracts, it may manifest with steatorrhea, malabsorption, hepatomegaly, splenomegaly, portal hypertension, and ascites, among others. To our knowledge, only one case of systemic mastocytosis has been reported affecting the appendix. We present another case of a 47-year-old woman who was admitted for right-sided acute abdominal pain and found to have systemic mastocytosis in her appendectomy specimen as the first and only manifestation of her disease.

European Competence Network on Mastocytosis (ECNM): 20-Year Jubilee, Updates, and Future Perspectives

In 2002, the European Competence Network on Mastocytosis (ECNM) was launched as a multidisciplinary collaborative initiative to increase the awareness and to improve diagnosis and management of patients with mast cell (MC) disorders. The ECNM consists of a net of specialized centers, expert physicians, and scientists who dedicate their work to MC diseases. One essential aim of the ECNM is to timely distribute all available information about the disease to patients, doctors, and scientists. In the past 20 years, the ECNM has expanded substantially and contributed successfully to the development of new diagnostic concepts, and to the classification, prognostication, and treatments of patients with mastocytosis and MC activation disorders. The ECNM also organized annual meetings and several working conferences, thereby supporting the development of the World Health Organization classification between 2002 and 2022. In addition, the ECNM established a robust and rapidly expanding patient registry and supported the development of new prognostic scoring systems and new treatment approaches. In all projects, ECNM representatives collaborated closely with their U.S. colleagues, various patient organizations, and other scientific networks. Finally, ECNM members have started several collaborations with industrial partners, leading to the preclinical development and clinical testing of KIT-targeting drugs in systemic mastocytosis, and some of these drugs received licensing approval in recent years. All these networking activities and collaborations have strengthened the ECNM and supported our efforts to increase awareness of MC disorders and to improve diagnosis, prognostication, and therapy in patients.

Systemic mastocytosis mimicking blastic plasmacytoid dendritic cell neoplasm: a case report

BACKGROUND

Systemic mastocytosis (SM), a rare myeloid neoplasm, is defined as a clonal and neoplastic proliferation of mast cells in at least one extracutaneous organ(s). The pathologic diagnosis and treatment of SM are challenging.

CASE PRESENTATION

We presented a 44-year-old male patient who had endured abdomen discomfort for 4 years and diarrhea for 5 months. Colonoscopy and PET/CT found a protuberant lesion in the cecum with adjacent lymphadenopathy. Histopathology of the cecum biopsy showed diffuse infiltration of medium-sized round/oval cells in lamina propria with immunohistochemical expressions of CD45, CD117, CD25, CD68, CD123, CD56, CD4, and CD35, mimicking blastic plasmacytoid dendritic cell neoplasm. Sanger sequencing revealed missense mutation (D816V) in the exon 17 of KIT gene. Serum tryptase level was 38.56 ng/ml. No abnormality was found in skin examination and bone marrow biopsy. No primitive cells were observed in bone marrow smear and peripheral blood smear. The diagnosis of aggressive SM with intestinal tract involvement was established. The patient received avapritinib treatment at an initial dosage of 200 mg once daily and exhibited dramatic clinical improvement but memory impairment within 1 month. No recurrence was observed in 1-year follow-up at the adjusted avapritinib dose (75 mg once daily).

CONCLUSIONS

SM is very rare and should be considered in patients with long-term diarrhea symptoms and hematopoietic/lymphoid-appearing tumors. KIT D816V mutation contributes to the differentiation of CD123, CD4, and CD56 immunoreactive SM from blastic plasmacytoid dendritic cell neoplasm. The rare side-effect of memory impairment in this case helps to accumulate the experience of avapritinib in treating KIT D816V-mutant SM.

A Rare Case of Aggressive Systemic Mastocytosis With Skeletal Osteosclerotic Lesions on Presentation: A Diagnostic Conundrum

Systemic mastocytosis (SM) is a heterogeneous group of disorders caused by mast cell proliferation. SM often presents with non-specific symptoms making it a diagnostic challenge. Moreover, presentation with bone involvement is highly uncommon. Here, we report a rare case of SM in a 68-year-old female who initially presented with gastrointestinal symptoms and was later found to have sclerotic bone lesions on imaging. This case highlights an unusual presentation of SM, informing clinicians of the importance of keeping this disease process on the differential list of diagnostic conundrums.

Is mastocytic colitis a specific clinical-pathological entity?

The number of intestinal mast cells (MC) is increased in several types of colitis, but the mucosa of patients with chronic non-bloody diarrhea has not been studied. The current study sought to determine the relationship between MC counts and degranulation and the severity of symptoms in patients with chronic loose stools. Following a negative laboratory workup for the most common causes of chronic diarrhea, patients with chronic non-bloody loose stools were included in the study. Patients with macroscopic evidence of inflammation or organic disease were excluded after endoscopy with biopsies. Biopsies from the 179 patients in the study were stained with hematoxylin and eosin and anti-CD117 c-kit antibodies. Immunohistochemistry was used to assess the degree of MC degranulation. Out of the 179 patients, 128 had normal histologic findings suggestive of irritable bowel syndrome and were used as controls. Twenty-four presented with abnormally high MC counts (≥40 MC x HPF), 23 with ≥20 intraepithelial lymphocytes x HPF suggesting lymphocytic colitis, and 4 had both (≥40 MC and ≥20 intraepithelial lymphocytes x HPF). In the patients with high MC counts, figures were significantly higher in the right colon versus the left colon (p=0.016), but degranulation did not differ in the right versus the left colon (p=0.125). No age or sex-related difference was observed (p=0.527 and p=0.859 respectively). The prevalence of abdominal pain and bloating did not differ in the three groups (p=0.959 and p=0.140, respectively). Patients with lymphocytic colitis (p=0.008) and those with high MC counts (p=0.025) had significantly higher evacuation rates compared to controls. There was no difference between these two groups (p=0.831). Mast cell degranulation was not associated with the number of evacuations, abdominal pain, or bloating (p=0.51; p=0.41; p=0.42, respectively). The finding that a significantly higher number of evacuations was linked to increased MC in the colonic mucosa of a subset of patients with otherwise normal laboratory and endoscopic findings suggests that "mastocytic colitis" may be a new clinical-pathological entity responsible for chronic non-bloody diarrhea. Prospective studies with a larger number of patients, as well as endoscopic and histological follow-up, are needed to confirm this hypothesis.

Rare gastrointestinal presentation of systemic mastocytosis, a case report

Introduction

Systemic mastocytosis is a rare disease resulting from infiltration of atypical mast cells in multiple organ systems and present with variety of symptoms. Primary appendiceal and cecal mass with isolated abdominal pain as a presenting feature in systemic mastocytosis have not been reported in literature up to now.

Case report

We described a 69- years-old female with systemic mastocytosis who presented with chronic abdominal pain and recent progression. On imaging of the abdomen and pelvis showed a mass in cecum. The patient underwent surgery and histopathologic evaluation of cecal and appendiceal masses revealed uniform small round cell tumor with eosinophilic cytoplasm admixed with many eosinophils distorting normal colonic mucosal architecture. The neoplastic cells showed positive expression of CD117 and Mast cell tryptase. According to all these considerations systemic mastocytosis was confirmed as the diagnosis.

Conclusion

Isolated abdominal pain and primary large intestinal mass are uncommon features of systemic mastocytosis. This case report informed physicians and pathologists to consider it as one of differential diagnosis.

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Mastocytosis is an uncommon neoplastic infiltration of mast cells in one or multiple organs.

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Isolated abdominal pain and primary large intestinal mass are uncommon features of systemic mastocytosis.

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Mastocytosis reveal common surprising clinical signs that to conclude lead to inadequate treatment. mastocytosis.

Mastocytosis-A Review of Disease Spectrum with Imaging Correlation

Simple Summary

In this review will discuss the clinical presentation, pathophysiology, and role of imaging in detection and extent estimation of the systemic involvement of the disease, in addition to demonstration of appearance on varying imaging modalities. Familiarity with the potential imaging findings associated with mastocytosis can aid in early disease diagnosis and classification and accordingly can lead directing further work up and better management.

Abstract

Mastocytosis is a rare disorder due to the abnormal proliferation of clonal mast cells. Mast cells exist in most tissues, mature in situ from hematopoietic stem cells and develop unique characteristics of local effector cells. Mastocytosis develops by activation mutation of the KIT surface receptor which is involved in the proliferation of a number of cell lines such as mast cells, germ cells, melanocytes, and hematopoietic cells. It manifests as two main categories: cutaneous mastocytosis and systemic mastocytosis. Imaging can play an important role in detection and characterization of the disease manifestation, not only by radiography and bone scans, but also magnetic resonance imaging and computed tomography, which can be more sensitive in the assessment of distinctive disease patterns. Radiologists should be aware of various appearances of this disease to better facilitate diagnosis and patient management. Accordingly, this review will discuss the clinical presentation, pathophysiology, and role of imaging in detection and extent estimation of the systemic involvement of the disease, in addition to demonstration of appearance on varying imaging modalities. Familiarity with the potential imaging findings associated with mastocytosis can aid in early disease diagnosis and classification and accordingly can lead directing further work up and better management.

Systemic Mastocytosis: Radiological Point of View

Radiological diagnosis of systemic mastocytosis (SM) can be hard to establish. This difficulty is mainly due to the variable radiological features involving many organ systems (e.g., respiratory, cardiovascular, lympho-reticular, digestive systems, and most commonly skin), and above all, to the broad spectrum of skeletal findings. Skeletal involvement is the most common and prominent imaging feature in patients with SM and represents a prognostic factor as it may entail an aggressive course of the disease. Diagnosis, largely established by histological evaluation of a bone marrow trephine biopsy, supplemented by imaging modalities such as radiography, CT, and magnetic resonance imaging, requires a team approach between the hematologist, radiologist, and pathologist. The general radiologist needs to be familiar with the imaging findings because they may be the first to suggest the correct diagnosis. The primary purpose of this review article was to equip clinicians with pertinent radiological semiotics by presenting relevant radiological features that assist early diagnosis and selection of an effective treatment.

Gastrointestinal Manifestations in Systemic Mastocytosis: The Need of a Multidisciplinary Approach

Simple Summary

Mastocytosis is a group of neoplastic mast cell disorders ranging from a skin-limited disease to a systemic form with multi-organ involvement, including gut involvement. Clinical manifestations and outcome of systemic mastocytosis are variable. Symptoms may result from either release of mast cell mediators or tissue infiltration by mast cell proliferation. Gastrointestinal symptoms are one of the major causes of morbidity in these patients. The diagnosis of gastrointestinal mastocytosis can be tricky, as symptoms often mimic other more common gastrointestinal diseases; the endoscopic appearance is often unremarkable or nonspecific and the infiltrate can be focal and subtle and easily missed unless special stains are used. This review aims to better define the gastrointestinal involvement in systemic mastocytosis, discussing potential diagnostic pitfalls and pointing out the importance of a multidisciplinary approach for a prompt diagnosis and treatment.

Abstract

Mastocytosis represents a heterogeneous group of neoplastic mast cell disorders. The basic classification into a skin-limited disease and a systemic form with multi-organ involvement remains valid. Systemic mastocytosis is a disease often hard to diagnose, characterized by different symptoms originating from either the release of mast cell mediators or organ damage due to mast cell infiltration. Gastrointestinal symptoms represent one of the major causes of morbidity, being present in 60–80% of patients. A high index of suspicion by clinicians and pathologists is required to reach the diagnosis. Gastrointestinal mastocytosis can be a challenging diagnosis, as symptoms simulate other more common gastrointestinal diseases. The endoscopic appearance is generally unremarkable or nonspecific and gastrointestinal mast cell infiltration can be focal and subtle, requiring an adequate sampling with multiple biopsies by the endoscopists. Special stains, such as CD117, tryptase, and CD25, should be performed in order not to miss the gastrointestinal mast cell infiltrate. A proper patient’s workup requires a multidisciplinary approach including gastroenterologists, endoscopists, hematologists, oncologists, and pathologists. The aim of this review is to analyze the clinicopathological features of gastrointestinal involvement in systemic mastocytosis, focusing on the relevance of a multidisciplinary approach.

Non-hematologic diagnosis of systemic mastocytosis: Collaboration of radiology and pathology

Systemic mastocytosis (SM) is a hematologic disease with a wide range of clinical courses ranging from an indolent condition with normal life expectancy to exceedingly aggressive disorder with a poor prognosis. The symptoms and signs of SM result from the release of mast cell mediators with heterogeneous functions, and/or organ damage from neoplastic mast cell infiltration, or both. Diagnostic criteria for SM are well-defined by the World Health Organization (WHO). However, the diagnosis of SM can be difficult when especially it is not in the differential diagnosis. Routinely used radiologic techniques (e.g., X-ray, ultrasound, CT scans can show findings such as lytic-, sclerotic- or mixed-bone lesions, splenomegaly, hepatomegaly, retroperitoneal or periportal mesenteric lymphadenopathy, and omental thickening). It is essential to emphasize that the constellation of these radiologic findings should strongly concern of SM, especially in patients who also have a skin rash, allergic reactions, gastrointestinal tract symptoms (lasting, intermittent nausea, diarrhea), paroxysmal tachycardias, unexplained weight loss, persistent bone pain, cytopenias, liver dysfunction, eosinophilia. These findings, even coincidentally noted, will likely lead to a tissue biopsy, which reveals diagnosis (as we discussed and illustrated some tissue biopsies here). Moreover, the role of MRI and new techniques such as [18-fluorodeoxyglucose positron emission computed tomography, fibroscan] in the diagnosis of SM have been discussed. Furthermore, we reviewed the use of radiologic methods to evaluate treatment response and prognostication of SM..

Gastrointestinal Mastocytosis: A Potential Diagnostic Pitfall to Be Aware

Mastocytosis is a rare and heterogeneous group of disorders that may be limited to the skin and even spontaneously regress or may have a systemic presentation with multi-organ involvement and poor outcome. Among the extracutaneous sites, gastrointestinal tract is often affected, but nonspecific clinical manifestations combined with subtle histological findings of the disease makes the diagnosis of gastrointestinal mastocytosis rather hard. In absence of a high index of suspicion, gastrointestinal involvement is easily overlooked. We report a challenging case of systemic mastocytosis presenting with isolated gastrointestinal manifestations without skin involvement, in which the diagnosis was missed at first evaluation of intestinal biopsies.

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.

Flushing Disorders Associated with Gastrointestinal Symptoms: Part 1, Neuroendocrine Tumors, Mast Cell Disorders and Hyperbasophila

Flushing is the subjective sensation of warmth accompanied by visible cutaneous erythema occurring throughout the body with a predilection for the face, neck, pinnae, and upper trunk where the skin is thinnest and cutaneous vessels are superficially located and in greatest numbers. Flushing can be present in either a wet or dry form depending upon whether neural-mediated mechanisms are involved. Activation of the sympathetic nervous system results in wet flushing, accompanied by diaphoresis, due to concomitant stimulation of eccrine sweat glands. Wet flushing is caused by certain medications, panic disorder and paroxysmal extreme pain disorder (PEPD). Vasodilator mediated flushing due to the formation and release of a variety of biogenic amines, neuropeptides and phospholipid mediators such as histamine, serotonin and prostaglandins, respectively, typically presents as dry flushing where sweating is characteristically absent. Flushing occurring with neuroendocrine tumors accompanied by gastrointestinal symptoms is generally of the dry flushing variant, which may be an important clinical clue to the differential diagnosis. A number of primary diseases of the gastrointestinal tract cause flushing, and conversely extra-intestinal conditions are associated with flushing and gastrointestinal symptoms. Gastrointestinal findings vary and include one or more of the following non-specific symptoms such as abdominal pain, nausea, vomiting, diarrhea or constipation. The purpose of this review is to provide a focused comprehensive discussion on the presentation, pathophysiology, diagnostic evaluation and management of those diseases that arise from the gastrointestinal tract or other site that may cause gastrointestinal symptoms secondarily accompanied by flushing. This review is divided into two parts given the scope of conditions that cause flushing and affect the gastrointestinal tract: Part 1 covers neuroendocrine tumors (carcinoid, pheochromocytomas, vasoactive intestinal polypeptide, medullary carcinoma of the thyroid), polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes (POEMS), and conditions involving mast cells and basophils; while Part 2 covers dumping syndrome, mesenteric traction syndrome, rosacea, hyperthyroidism and thyroid storm, anaphylaxis, panic disorders, paroxysmal extreme pain disorder, and food, alcohol and medications.

[Mastocytosis : Clinical aspects, diagnostics, therapy]

Mastocytosis is a rare, almost exclusively sporadically occurring disease involving an increase in clonal tissue mast cells. The disease spectrum is heterogenous, ranging from isolated skin lesions with a normal life expectancy to rare, aggressive forms with very poor prognosis. Children are often affected. But whereas these almost invariantly display solely a cutaneous mastocytosis with polymorphous skin lesions, in adults the lesions are small and maculopapular and in over 80% of cases accompanied by involvement of bone marrow and the D816V activating mutation of the gene for the c‑Kit receptor. There are many symptoms for the disease. Patients suffer frequently from pruritus, diarrhea, abdominal cramp, palpitations and flush. Osteoporosis is often present, with osteolysis with pathological fractures frequently involved in more aggressive forms. Patients are especially at risk to severe anaphylaxis caused by hymenoptera stings. Therapy is symptomatic, with cytoreductive therapy reserved for resistant and aggressive forms.

Decreased tryptophan and increased kynurenine levels in mastocytosis associated with digestive symptoms

The main metabolism pathway of tryptophan is protein formation, but it can also be metabolized into serotonin and kynurenine. Indoleamine 2,3-dioxygenase (IDO) is the enzyme that catalyzes the degradation of tryptophan into kynurenine. Mastocytosis is a heterogeneous disease characterized by mast cell accumulation in various tissues with 57% of patients having gastrointestinal involvement. We studied tryptophan metabolism in mastocytosis patients displaying or not gastrointestinal features and healthy subjects (n = 26 in each group). Mastocytosis patients with digestive symptoms displayed significantly increased kynurenine level and IDO activity as compared to healthy controls and mastocytosis patients without digestive symptoms. This could be linked to mast cell-mediated digestive inflammation among patients with mastocytosis. This work is the first focusing on kynurenine pathway in a mast cell disease and could help to understand the pathogenesis of digestive features in mastocytosis as well as in other mast cell-mediated diseases.

A Case of Intestinal Mastocytosis Misdiagnosed as Crohn's Disease

Systemic mastocytosis (SM) is a rare, heterogeneous and progressive disease, characterized by the accumulation of atypical mast cells in various organs, including the gastrointestinal tract. Gastrointestinal symptoms are present in up to 80% of patients with SM, the most common being abdominal pain, diarrhea, nausea and vomiting. Up to 50% of patients with SM do not have classical skin lesions at presentation, and in these patients the diagnosis of SM can be difficult for years. Here we report a case of SM that initially mimicked inflammatory bowel disease, although the patient showed poor response to steroid therapy. The right diagnosis was made only on the surgical specimen obtained after emergency surgery for intestinal obstruction. SM should therefore be considered in the diagnostic approach in patients with gastrointestinal symptoms not attributable to other pathologies and in cases of suspected inflammatory bowel disease with unusual course.

Histamine H₄ receptors in the gastrointestinal tract

Histamine is a well-established mediator involved in a variety of physiological and pathophysiological mechanisms and exerts its effect through activation of four histamine receptors (H1-H₄). The histamine H₄ receptor is the newest member of this histamine receptor family, and is expressed throughout the gastrointestinal tract as well as in the liver, pancreas and bile ducts. Functional studies using a combination of selective and non-selective H₄ receptor ligands have rapidly increased our knowledge of H₄ receptor involvement in gastrointestinal processes both under physiological conditions and in models of disease. Strong evidence points towards a role for H₄ receptors in the modulation of immune-mediated responses in gut inflammation such as in colitis, ischaemia/reperfusion injury, radiation-induced enteropathy and allergic gut reactions. In addition, data have emerged implicating H₄ receptors in gastrointestinal cancerogenesis, sensory signalling, and visceral pain as well as in gastric ulceration. These studies highlight the potential of H₄ receptor targeted therapy in the treatment of various gastrointestinal disorders such as inflammatory bowel disease, irritable bowel syndrome and cancer.

Leukocyte telomere length in mastocytosis: correlations with depression and perceived stress

BACKGROUND

Mastocytosisis a rare disease associated with chronic symptoms related to mast cell mediator release. Patients with mastocytosis display high level of negative emotionality such as depression and stress sensibility. Brain mast cells are mainly localized in the diencephalon, which is linked to emotion regulatory systems. Negative emotionality has been shown to be associated with telomere shortening. Taken together these observations led us to hypothesize that mast cells activity could be involved in both negative emotionality and telomere shortening in mastocytosis.

OBJECTIVE

To demonstrate a possible relationship between negative emotionality in mastocytosis and leukocytes telomere length.

METHODS

Leukocyte telomere length and telomerase activity were measured among mastocytosis patients and were correlated with perceived stress and depression assessed by the Beck Depression Inventory revised and the Perceived Stress Scale.

RESULTS

Mild-severe depression scores were frequent (78.9%) as well as high perceived stress (42.11%). Telomere length was correlated to perceived stress (r=0.77; p=0.0001) but not to depression in our population. Patients displaying Wild-type KIT significantly presented higher perceived stress levels. Patients with the D816VC KIT mutation who had high perceived stress scores displayed significantly shorter telomere but not if they had high depression scores.

CONCLUSION

These findings suggest that high perceived stress in mastocytosis could accelerate the rate of leukocytes telomere shortening. Since mastocytosis is, by definition, a mast cell mediated disease; these cells could be involved in this phenomenon. Mechanistic causal relationships between these parameters need to be investigated.

Systemic mastocytosis involving the gastrointestinal tract: case report and review

Mastocytosis is rare, and is actually a heterogeneous group of diseases that may only involve the skin (urticaria pigmentosa) or that may have a systemic presentation with multiorgan involvement. The gastrointestinal (GI) tract can be affected and symptoms related to GI involvement are often nonspecific. The diagnosis of systemic mastocytosis with primarily GI presentation can be challenging and requires familiarity with this entity and a high index of suspicion. We report a case of systemic mastocytosis primarily diagnosed by the recognition of small intestinal and colonic involvement and review the diagnostic criteria, histopathology, and recent developments regarding this entity.

Mast cells and inflammation

The prominent role for mast cells in the inflammatory response has been increasingly well documented in recent years. Mast cells not only contribute to maintain homeostasis via degranulation and to generate IgE-mediated allergic reactions, but also sit at a major crossroads for both innate and adaptive immune responses. The part played by mast cells in chronic inflammatory diseases such as rheumatoid arthritis and multiple sclerosis identifies mast cells as a valuable treatment target in these diseases. Tyrosine-kinase inhibitors targeting the c-Kit mast cell receptor have been found effective in treating rheumatoid arthritis, asthma, and multiple sclerosis. When used in combination with other available drugs, tyrosine-kinase inhibitors may improve the therapeutic management of these diseases.

[Bullous mastocytosis in infancy: a rare presentation]

Mastocytosis is a rare condition related to an abnormal proliferation of mast cells and their accumulation in tissues. Cutaneous mastocytosis is the most common form and mainly affects newborns and infants. The symptoms are caused by the release of mediators contained in mast cells, including histamine. Mastocytosis may be associated with a mutation in the gene encoding the c-kit receptor. Clinically, there are different dermatological findings, which combine acute cutaneous, digestive, or even hemodynamic manifestations in varying degrees. The diagnosis is confirmed by the histological study of a skin sample. We report here the case of a 4-month-old infant suffering from diffuse cutaneous bullous mastocytosis, a very rare variety of mastocytosis. This infant had an erosive and bullous manifestation of dermatosis, initially confused with impetigo. The proliferation of bullous lesions led to her hospitalization. Codeine intake for pain was responsible for a large and extensive bullous reaction associated with anaphylactic shock. This context of bullous spread occurring after taking codeine led to the suspicion of bullous diffuse cutaneous mastocytosis, a diagnosis that was confirmed histologically. This observation demonstrates the difficulty of mastocytosis diagnosis, mostly due to its rarity, especially in its diffuse bullous forms. The rapid deterioration of this patient, after the codeine prescription, emphasizes the importance of the eviction of histamine-releaser compounds in the management of this disease.

Allergic mastocytic gastroenteritis and colitis: an unexplained etiology in chronic abdominal pain and gastrointestinal dysmotility

Abdominal pain, bloating, early satiety, and changes in bowel habits are common presenting symptoms in individuals with functional GI disorders. Emerging data suggests that these symptoms may be associated with mast cell excess and/or mast cell instability in the GI tract. The aim of this retrospective study was to evaluate the contribution of mast cells to the aforementioned symptoms in individuals with a history of atopic disease. A retrospective chart review of individuals seen in a university GI practice was conducted and twenty-four subjects were identified. The majority had abdominal pain, early satiety, and nocturnal awakening. 66.7% and 37.5% had a history of environmental and/or food allergy. Solid gastric emptying was increased as were the mean number of mast cells reported on biopsies from the stomach, small bowel, and colon (>37/hpf) by CD117 staining. Mean whole blood histamine levels were uniformly elevated. This study suggests that in individuals with these characteristics, consideration should be given to staining their gastrointestinal biopsies for mast cells as this may provide them with relatively non-toxic but highly targeted treatment options. Allergic gastroenteritis and colitis may represent a third type of GI mast cell disorder along with mast cell activation syndrome and mastocytic enterocolitis.

Update on diagnosis and treatment of mastocytosis

Mastocytosis is a disorder characterized by increased numbers of mast cells in tissues. Recent clinical observations highlight the association of mastocytosis with an increased risk of anaphylaxis and underline the diversity of this disease. At the molecular level, recent studies have attempted to unravel specific gene expression profiles for activating c-kit mutations in the etiology of mastocytosis. The diagnosis may be facilitated by surrogate markers and detection of aberrant immunophenotypic surface markers. New therapeutic strategies are in development based on intracellular signal pathways, or on application of topical treatments, as are novel forms of cytoreductive therapy, including tyrosine kinase inhibitors.

Histopathologic diagnosis of eosinophilic conditions in the gastrointestinal tract

Eosinophils, a constitutive component of the columnar-lined gastrointestinal tract, play an essential role in allergic responses and parasitic infections. The tissue density of these cells also increases in a variety of conditions of uncertain etiology. With the exception of the esophageal squamous epithelium, in which no eosinophils are normally present, the population of normal eosinophils in the remainder of the luminal gut is poorly defined. Therefore, histopathologists must rely on their subjective judgment to determine when a diagnosis of eosinophilic gastritis, enteritis, or colitis should be rendered. Eosinophilic esophagitis is currently the best defined and most studied eosinophilic condition of the digestive tract; therefore, the confidence in accurate diagnosis is increasing. In contrast, the characteristic clinicopathologic features of eosinophilic conditions affecting other parts of the digestive tract remain somewhat elusive. This review was designed to present pathologists with simple and practical information for the biopsy-based histopathologic diagnosis of eosinophilic esophagitis, gastritis, enteritis, and colitis. It was prepared by critically reviewing more than 200 articles on the topic, along with incorporating evidence accumulated through our own collective experience. We anticipate that by increasing pathologists' confidence in reporting these abnormal but often nameless eosinophilic infiltrates, we can help better define and characterize their significance.