Skeletal mastocytosis.

AIMS--To characterise the condition of skeletal mastocytosis, an uncommon cause of apparently "idiopathic" osteoporosis. METHODS--Transiliac crest biopsy specimens submitted over a period of five years were examined for nodular accumulation of mast cells. The cases were reviewed histologically and clinical follow up was obtained from hospital notes. RESULTS--Six cases of mastocytosis occurring in bone biopsy specimens submitted to our department were identified. Four patients presented initially with vertebral collapse and the other two were known to have extraskeletal mast cell disease at presentation. On clinical review of the four patients with vertebral collapse, one was found to have urticaria pigmentosa. This patient died from his mastocytosis, whereas the three patients without evidence of extraskeletal disease remain alive and well. Histological examination showed that patients with the poorer clinical outcome had severe peritrabecular fibrosis as well as mast cell nodules; those with prolonged disease-free survival had nodules without peritrabecular fibrosis. CONCLUSION--There is a form of mastocytosis which presents clinically as "idiopathic" osteoporosis. Clinically it does not have the same prognostic implications as skeletal disease in "malignant mastocytosis", running a much more benign course.     

Systemic Mastocytosis: Case Report and Literature Review

A case of systemic mastocytosis is reported and the literature reviewed. Although the dermatological manifestation of this rare disease, in the form of urticaria pigmentosa, is well recognized and goes along with the osteosclerotic changes that can be seen with systemic mastocytosis, it is imperative to rule out malignancy as a cause for a new onset of ascites and newly discovered sclerotic osseous changes.     

Proliferation of reactive and neoplastic human tissue mast cells. An immunohistochemical study using the antibody PC10 (anti-PCNA)

Studies on the proliferative compartment of human tissue mast cells (MCs) and their tumours (mastocytosis) have not been performed. We have used the monoclonal antibody PC 10 to study MCs in reactive or hyperplastic states (chronic non-specific lymphadenitis, n = 10; benign and malignant solid tumours, n = 5) and in the various subtypes of mastocytosis (urticaria pigmentosa, n = 22; solitary mastocytoma of the skin, n = 7; systemic mastocytosis; n = 8; malignant mastocytosis, n = 4). The identification of PC10-positive MC nuclei was achieved by double staining. We found no PC10-positive MCs in reactive or hyperplastic states, or in 14 of 22 cases of urticaria pigmentosa. PC 10-positive MCs could be identified in all other mastocytoses but mostly in very low numbers. The mean percentages of PC10-positive MCs amounted to 0.5 in eight positive cases of urticaria pigmentosa, 1.2 in mastocytoma, 0.7 in sytemic mastocytosis, and 4.0 in malignant mastocytosis. The difference between the latter form of mastocytosis and each of the other subtypes proved to be significant (P<0.05). The very smali proliferative compartment in the cutaneous and sytemic variants of mastocytosis is in accord with their favourable prognosis Most of the patients with systemic mastocytosis in the present study are all alive and well up to 12 years after diagnosis. In contrast, most of the patients with malignant mastocytosis died within 1 year of diagnosis.     

Cutaneous manifestations in Hymenoptera and Diptera anaphylaxis: relationship with basal serum tryptase

Objectives To compare the clinical presentation of systemic anaphylaxis to Hymenoptera and Diptera with regard to basal serum tryptase (BT) and to evaluate mastocytosis in patients with elevated tryptase.
Patients and Methods The medical records of 140 patients with a history of a systemic reaction to venom were retrospectively reviewed. Symptoms and severity of anaphylaxis and BT were recorded. Most patients with elevated tryptase were screened for mastocytosis: a dermatological examination with a skin biopsy was performed in 19 cases and a bone marrow biopsy in 14 cases.
Results Tryptase was elevated in 23 patients. These patients reported fewer usual skin reactions (urticaria in 26.1% of cases with raised tryptase vs. 76.1% of cases with normal tryptase), more flushing (52.2% vs. 4.3%) and frequently did not present skin reaction (26.1% vs. 9.4%). They presented a more severe reaction (mean grade of severity: 3.48 vs. 2.69). Mastocytosis was diagnosed in seven patients with elevated tryptase: indolent systemic mastocytosis in six cases and cutaneous mastocytosis without systemic involvement in one case. In five cases, mastocytosis was previously undiagnosed. Lesions of cutaneous mastocytosis, diagnosed in five patients, consisted of urticaria pigmentosa in all cases and were often inconspicuous.
Conclusion These results demonstrate particular clinical features of the allergic reaction in patients with elevated BT and the higher frequency of mastocytosis in this population. In patients with a severe anaphylactic reaction without urticaria, but with flushing, tryptase should be assayed and an underlying mastocytosis should be considered.     

Clinical varieties of mastocytoses

Varieties of the clinical features of mastocytoses, also called mastocytosis syndrome, are presented. The disease is characterized by excessive accumulation of mast cells, their proliferation and action in the skin and other organs, even in the central nervous system. The mastocytosis syndrome was known as early as the second half of the 19th century under the term urticaria pigmentosa, and was histologically confirmed by the presence in the dermis of metachromatic cells, i.e. Ehrlich mast cells with red-purple cytoplasmic granules visible with Giemsa or toluidine blue stains. The mastocytosis syndrome was then supposed to be a benign chronic dermatosis of childhood with spontaneous regression by adolescence. The clinically pathognomonic symptoms of Darier's sign (urtication of primary skin lesion upon rubbing) and flushing help in the diagnosis of mastocytosis syndrome. In the 1950s, there was a progression in the diagnosis of systemic mastocytosis achieved by scientists and clinicians of various specialties. Upon the discovery of many mast cell released mediators (heparin, histamine, leukotrienes, prostaglandins, proteases, cytokines), receptor functions, relationship to IgE, anaphylatoxin, etc., they were recognized as triggers of various clinical features of the mastocytosis syndrome. In this paper, different forms of cutaneous and systemic mastocytosis are described, with special reference to 'mastocytosis mucocutanea haemorrhagica' observed by one of the authors in a female infant and followed from 6 months till 2.5 years of age. The patient showed practically all the diverse forms of cutaneous mastocytosis: urticaria pigmentosa, papular, nodular, tumorous-like melanoma, vesiculobullous, erythrodermic, telangiectasia eruptiva maculosa perstans. She also suffered from nasal and rectal hemorrhage, conjunctival suggillations, plaque-like infiltrations of the glossal, oropharyngeal and laryngotracheal mucosa, episodes of flushing, and transitory apnea. It is emphasized that the diagnosis of mastocytosis syndrome may be difficult for its mimicking various other diseases. The occurence of mastocytosis syndrome from the neonatal period through adult and old age, and possibilities of symptomatic treatment and prevention of sudden death or fatalities are discussed. Familial occurrence of mastocytosis syndrome and new genetic studies that may prove highly useful for understanding the etiopathogenesis of mastocytosis syndrome are described.     

Indolent systemic mastocytosis with elevated serum tryptase, absence of skin lesions, and recurrent severe anaphylactoid episodes

BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms.     

Evaluation of mast cell activation syndromes: impact of pathology and immunohistology

Mast cell activation syndromes (MCAS) are clinically defined disease states with a largely unknown morphological background. Since mastocytosis may be associated with MCAS, it is crucial in every patient to document or exclude mastocytosis by appropriate histological, molecular, and serological investigations of tissues/organs that are commonly involved in mastocytosis like skin, mucosa of the gastrointestinal tract and bone marrow. Accordingly, histopathological investigation including immunohistological stains is crucial to reach the final diagnosis in such patients and to classify MCAS into primary MCAS, which can present with or without evidence of overt mastocytosis, or secondary MCAS, where an underlying disease with or without tissue inflammation is detected. Cases without evidence of mastocytosis, monoclonal mast cells, or any underlying disease should be termed idiopathic MCAS. When the activating point mutant KIT D816V is detectable but criteria for diagnosis of mastocytosis are not completely met, a so-called (mono)clonal MCAS as a subvariant of primary MCAS should be diagnosed.     

Hematopathology of the bone marrow in pediatric cutaneous mastocytosis. A study of 17 patients

Sixteen bone marrow aspirates and 15 trephine core biopsies from 17 children with cutaneous mastocytosis, of which 15 exhibited urticaria pigmentosa and 2 exhibited diffuse cutaneous mastocytosis, were evaluated for the presence of bone marrow-associated pathologic conditions. Eight bone marrow aspirates from 8 children and 23 trephine core bone marrow biopsies from 16 children who had had evaluation for hematologic abnormalities not associated with cutaneous mastocytosis served as a control population. Eosinophilia was a prominent finding in bone marrows of 9 of 17 patients who had cutaneous mastocytosis. Increased mast cell numbers in bone marrow aspirates were observed in 5 children with cutaneous mastocytosis (5 of 16) and in 2 of the control children (2 of 8). Examination of the trephine core bone marrow biopsies obtained from patients with cutaneous mastocytosis demonstrated focal perivascular and paratrabecular aggregates consisting of mast cells, eosinophils, and early myeloid cells in 10 of 15 individuals. Similar lesions were observed in trephine core bone marrow biopsies of 3 of 16 control patients. The focal mast cell lesions characteristic of adult systemic mastocytosis were not observed. The authors conclude that cutaneous mastocytosis in the pediatric age group is rarely associated with definitive bone marrow findings suggestive of systemic mast cell disease and that this observation is consistent with previous reports that cutaneous mastocytosis in the majority of pediatric cases resolves by adulthood.     

Systemic mastocytosis, myelofibrosis and portal hypertension.

A case of systemic mastocytosis is described in which the finding on initial presentation was hepatosplenomegaly. No dermatological abnormality was present, and the bone marrow histology originally caused some confusion with primary myelofibrosis. The clinical course and the importance of distinguishing between these two diseases is discussed. The dermatological manifestation of systemic mastocytosis, in the form of urticaria pigmentosa, is well recognised, and alerts the physician to the underlying disease. In the absence of cutaneous signs, however, the diagnosis is less obvious. The case reported had predominantly marrow and splenic involvement by the disease process, giving rise to portal hypertension, and illustrates the problems of diagnosis which can arise.     

Fatal anaphylactic sting reaction in a patient with mastocytosis

We report on a 33-year-old female patient with indolent systemic mastocytosis and urticaria pigmentosa who died of an anaphylactic reaction after a yellow jacket sting. As she had no history of previous anaphylactic sting reaction, there was no testing performed in order to detect hymenoptera venom sensitization. But even if a sensitization had been diagnosed, no venom immunotherapy (VIT) would have been recommended. It is almost certain that VIT would have saved her life and it is most likely that VIT is indicated in some patients with mastocytosis with no history of anaphylactic sting reaction. However, no criteria have been established in order to allow a selection of mastocytosis patients eligible for such a 'prophylactic' VIT.     

Assessment of tissue fluid histamine levels in patients with urticaria

Tissue fluid histamine in lesions and normal skin sites of patients with various forms of physically induced urticaria and chronic idiopathic urticaria was assessed utilizing suction-induced blisters. Histamine levels were elevated over challenged sites in cold urticaria, solar urticaria, and delayed pressure urticaria. Histamine levels were elevated in both challenged and “control” sites in patients with immediate-pressure urticaria and local heat urticaria in whom the apparatus provoked lesions. In 5 of 13 patients with chronic idiopathic urticaria, the blister fluid histamine levels were elevated in lesions but not in normal-appearing skin, while in 7 patients the blister fluid histamine levels were elevated in lesions as well as in normal-appearing skin. Although the pathogenesis of chronic idiopathic urticaria is unknown, a clear abnormality related to skin histamine has been identified.     

Gastrointestinal manifestations of systemic mastocytosis

Systemic mastocytosis (SM) is an uncommon neoplastic proliferation of mast cells involving single or multiple organs. The skin is most commonly involved, presenting as urticaria pigmentosa, followed by bone marrow involvement, which is the commonest extracutaneous. The gastrointestinal tract is reported to be involved in about 70–80% of cases of systemic mastocytosis. The pattern and extent of mucosal involvement and the histological appearance are now becoming clear as there is heightened awareness by clinicians of the possibility of the gastrointestinal tract being affected by the disease and increased endoscopic procedures. The symptoms appear non-specific with abdominal pain as the leading complaint followed by nausea, vomiting and diarrhoea. Cases of systemic mastocytosis are being diagnosed by mucosal biopsies with gastrointestinal involvement as the presenting pathology. A case of systemic mastocytosis is described diagnosed on gastrointestinal symptoms and endoscopic mucosal biopsies.     

Are gastrointestinal mucosal mast cells increased in patients with systemic mastocytosis?

In patients with mastocytosis, gastrointestinal symptoms are a frequent phenomenon. However, there are only limited data about the quantity and distribution pattern of mast cells in the gastrointestinal mucosa. We stained gastroduodenal biopsy specimens from 27 patients with mastocytosis and 48 control subjects for mast cell tryptase, CD117, and CD25. The numbers of mucosal mast cells per high-power field showed wide variation in all groups and were decreased markedly in biopsy specimens of corpus and duodenum and statistically significantly decreased in antrum biopsy specimens from patients with systemic mastocytosis compared with patients with pure urticaria pigmentosa and with control subjects. Staining for tryptase showed highly significant correlation with staining for CD117. All mast cells were negative for CD25, which is expressed characteristically by neoplastic mast cells. Causes of the decrease of mucosal mast cells remain enigmatic, but our results show that gastrointestinal symptoms of patients with mastocytosis are most likely mediator-related and not due to an increase of local mast cells.     

Advances in therapy with antileukotriene drugs

Evidence from clinical trials and experience derived from managing patients with asthma justify a broader role for leukotriene (LT) blockers in asthma management than that recommended by the National Asthma Education and Prevention Program and the NIH Heart, Lung and Blood Institute treatment guidelines. Many published clinical trials, reviews, and case reports have suggested important new applications of LT blockers (ie, montelukast, zafirlukast, pranlukast, and zileuton) in several diseases in which leukotrienes play a pathogenic role. These include paranasal sinus disease, allergic fungal sinusitis, migraine, chronic urticaria, atopic dermatitis, chronic obstructive pulmonary disease, allergic conjunctivitis, mastocytosis, bronchiolitis, idiopathic pulmonary fibrosis, interstitial cystitis, and irritable bowel syndrome. Although double-blind, randomized, placebo-controlled trials are needed to confirm the effects that these drugs may have in these diseases, the aim of this short review is to delineate the future roles that these drugs may have in the management of these conditions.     

Spectrum of mast cell activation disorders

Mast cell (MC) activation disorders present with multiple symptoms including flushing, pruritus, hypotension, gastrointestinal complaints, irritability, headaches, concentration/memory loss and neuropsychiatric issues. These disorders are classified as: cutaneous and systemic mastocytosis with a c-kit mutation and clonal MC activation disorder, allergies, urticarias and inflammatory disorders and mast cell activation syndrome (MCAS), idiopathic urticaria and angioedema. MCs are activated by IgE, but also by cytokines, environmental, food, infectious, drug and stress triggers, leading to secretion of multiple mediators. The symptom profile and comorbidities associated with these disorders, such as chronic fatigue syndrome and fibromyalgia, are confusing. We propose the use of the term ‘spectrum’ and highlight the main symptoms, useful diagnostic tests and treatment approaches.     

Assessment of urticaria and angio-oedema

There are many types of urticaria and the principal form of assessment is by clinical history and examination. Urticarial weal formation involves acute, reversible vasodilatation and increased vascular permeability. If the process is deeper the more diffuse swelling is termed angio-oedema. The major types of urticaria include allergic, physical and idiopathic forms. In allergic urticaria, IgE-mediated degranulation of mast cells results in weals of short duration which typically respond well to antihistamines. Physical urticarias are induced by physical insults including pressure, scratch, cold, etc. The distribution and duration of individual weals may suggest the causal factor. Chronic idiopathic urticaria can be very variable, with individual weals lasting between 90 min and 24 hours. Longer-lasting weals are less responsive to anti-histamines and clearly involve other mediators. When long-lasting weals fade leaving a bruised appearance urticarial vasculitis is present which may only respond to systemic corticosteroids. In a proportion of individuals with chronic idiopathic urticaria, auto-antibodies are present with specificity for the high affinity receptor for IgE or sometimes, for IgE itself. In general laboratory tests for allergic factors or other assessments of general health are completely unhelpful.     

Chronic urticaria sera increase basophil CD203c expression

BACKGROUND: Approximately 40% of patients with chronic idiopathic urticaria have antibodies to the alpha subunit of the high-affinity IgE receptor. CD203c is a basophil activation marker known to be upregulated by cross-linking of the FcepsilonRIalpha receptor and may serve as a useful marker to identify these patients. OBJECTIVE: The primary objective was to assess the affect of sera from patients with chronic idiopathic urticaria on basophil CD203c expression. Secondary objectives were to correlate CD203c expression with basophil histamine release and size of the autologous serum skin test and to determine whether the mechanism is mediated by an IgG antibody. METHODS: Sera were obtained from patients with chronic idiopathic urticaria and positive autologous serum skin test or negative autologous serum skin test and normal controls. Sera were incubated with donor whole blood. Activated basophils from whole blood were identified by flow cytometry on the basis of the presence of CD203c on high-expressing IgE positive cells. RESULTS: Incubation of donor basophils with sera from patients with chronic idiopathic urticaria and positive autologous serum skin test demonstrated significant upregulation of CD203c. IgG depletion of representative sera from patients with chronic idiopathic urticaria resulted in significant decrease in CD203c expression on donor basophils. CD203c expression correlated with basophil histamine release and the size of the autologous serum skin test. CONCLUSION: Sera from patients with chronic idiopathic urticaria and positive autologous serum skin test significantly upregulate basophil CD203c and correlate with basophil histamine release. CLINICAL IMPLICATIONS: This article describes an activation marker on basophils whose expression is increased by sera from patients with chronic idiopathic urticaria.     

Mast cell mediators in allergic inflammation and mastocytosis

Mast cells possess an array of potent inflammatory mediators capable of inducing acute symptoms after cell activation, including urticaria, angioedema, bronchoconstriction, diarrhea, vomiting, hypotension, cardiovascular collapse, and death in few minutes. In contrast, mast cells can provide an array of beneficial mediators in the setting of acute infections, cardiovascular diseases, and cancer. The balance between the detrimental and beneficial roles of mast cells is not completely understood. Although the symptoms of acute mast cell mediator release can be reversed with epinephrine, adrenergic agonists, and mediator blockers, the continued release of histamine, proteases, prostaglandins, leukotrienes, cytokines, and chemokines leads to chronic and debilitating disease, such as mastocytosis. Identification of the molecular factors and mechanisms that control the synthesis and release of mast cell mediators should benefit all patients with mast cell activation syndromes and mastocytosis.     

Mast cells and T lymphocytes in chronic urticaria

Mast cells are considered to be the primary effector cells in urticaria but it is possible that lymphocytes contribute to the formation of weals by secreting histamine releasing factors. The aim of this study was to examine the population of mast cells and to quantify the T cell subsets and their activation status in delayed pressure urticaria (DPU), chronic idiopathic urticaria and normal controls. Three biopsies were obtained from each of four patients with chronic idiopathic urticaria but not DPU. Three biopsies were taken from each of 13 patients with DPU, from a combination of unchallenged skin and at 0, 2, 6, 24, 48 and 120 h after weighted steel rods (diameter 1.5 cm) had been applied to the thighs. Three biopsies were similarly obtained from each of four normal controls before an identical pressure challenge and at 6, 24 and 48 h afterwards. The chloracetate esterase stain was used to demonstrate mast cells and an alkaline phosphatase anti-alkaline phosphatase immunohistochemical technique to assess the phenotypic and activation characteristics of the T cell infiltrate. The mast cell count did not differ significantly between unchallenged skin from DPU patients and normal controls. Following a pressure challenge to the DPU patients, the number of stainable mast cells decreased significantly to a level comparable with that in spontaneous weals of chronic idiopathic urticaria. Investigation of T cell subsets showed a preponderance of CD4+ cells over CD8+ cells. There was no evidence of T cell activation in chronic idiopathic urticaria or DPU when compared with normal controls. These data support the view that mast cell degranulation occurs in chronic idiopathic urticaria and suggest that it may also play a role in the pathogenesis of DPU. There was no evidence that lymphocyte activation occurs in either condition.