Feline maculopapular cutaneous mastocytosis: a retrospective study of 13 cases and proposal for a new classification.

CASE SERIES SUMMARY: Cutaneous mastocytosis is a disorder rarely reported in veterinary dermatology and usually described as 'urticaria pigmentosa'. This study aimed to evaluate the diagnosis, treatment and outcome of 13 affected cats, selected from the files of a private referral dermatology practice within a period of 14 years. Breeds of the affected individuals included Sphynx (n = 9), Devon Rex (n = 2) and Sphynx/Devon Rex crossbreeds (n = 2). Females (n = 9) were over-represented and the median duration of clinical signs prior to diagnosis was 8 months. The clinical presentation of these 13 cats was compared with cases reported in the veterinary literature and classified according to the current human consensus on cutaneous mastocytosis. Three clinical forms could be distinguished in cats: (1) large papular lesions and wheals, typically localised to the head, shoulders, ventral neck and axillae, and which may spontaneously resolve (termed polymorphic maculopapular cutaneous mastocytosis); (2) erythematous dermatitis, characterised by small maculopapular lesions often associated with crusts and with a poorer prognosis (termed monomorphic maculopapular cutaneous mastocytosis); and (3) more chronic dermatitis characterised by lichenification and hyperpigmentation, similar to the human condition 'urticaria pigmentosa' (termed pigmented maculopapular cutaneous mastocytosis). Histopathology was performed in eight cases and revealed a superficial-to-deep dermatitis characterised by infiltrates of mast cells and eosinophils. The response to various treatments, including antihistamines, steroids and ciclosporin, was variable. RELEVANCE AND NOVEL INFORMATION: This article reports 13 new cases of feline cutaneous mastocytosis, confirming the clinical presentation and apparent breed predisposition. The feline maculopapular cutaneous mastocytosis seems to be clinically very close to the human form. This study proposes a new classification system for the feline disease based on the current human consensus, clinical presentation and prognosis, with three different subforms: polymorphic maculopapular cutaneous mastocytosis with eventual spontaneous regression; monomorphic maculopapular cutaneous mastocytosis with chronic evolution; and pigmented maculopapular cutaneous mastocytosis.

Telangiectasia macularis eruptiva perstans: an old terminology, still frequently used.

The term telangiectasia macularis eruptiva perstans (TMEP) was originally used to describe a rare form of cutaneous mastocytosis (CM) that was limited to the skin with lesions consisting of irregular, telangiectatic macules ranging in color from red to brown. Recent guidelines, however, recommended that the sole presence of telangiectasias should not form the basis of a distinct variant of CM. We conducted a review of the literature from 1930 to 2017 and found 76 cases that were reported as TMEP. Owing to a general misconception about diagnosis of CM and SM, there is a need for further discussion and awareness of the newly proposed World Health Organization (WHO) guidelines.

[Mastocytosis--diagnostic criteria and treatment]. / Mastocytoza--rozpoznawanie i leczenie.

Mastocytosis is a heterogeneous group of rare diseases characterized by the proliferation and accumulation of mast cells in one or more organs such as the skin, bone marrow, liver, spleen, and lymph nodes. According to the WHO classification, mastocytosis is divided into seven subvariants. The symptoms are associated with mediator release and impaired organ function due to infiltration by neoplastic mast cells. There is a higher risk of anaphylactic shock; therefore education of the patients is very important. Patients may be asymptomatic. Symptomatic treatment is used in cutaneous mastocytosis and in indolent systemic mastocytosis. More aggressive subvariants of mastocytosis are treated with chemotherapy, targeted therapy, and bone marrow transplantation.

Diffuse cutaneous mastocytosis: pseudoxanthomatous variant.

Diffuse cutaneous mastocytosis is one of the extremely rare benign forms of mastocytosis that have varied clinical presentations. The pseudoxanthomatous variant is an extremely rare multinodular nonpigmented entity. Only two cases have been reported so far in the literature. We report a 21 year old female patient who had diffusely infiltrated skin with multiple papulo-nodular lesions resembling xanthomas and the classical histopathological features of mastocytosis.

A proposed classification of mastocytosis incorporating molecular genetics.

As an understanding of the molecular genetic causes of different forms of mastocytosis is developed, the therapy of choice may depend on the specific genetic abnormalities expressed by a patient's neoplastic mast cells. The authors propose a new classification system for mastocytosis that incorporates both molecular-genetic and clinical data. This system provides a theoretic framework for mast cell researchers and helps practicing physicians in estimating prognosis and determining therapeutic options for individual patients.

[Classification and management of mastocytosis in the child]. / Classification et prise en charge des mastocytoses de l'enfant.

OBJECTIVE: Mastocytosis is a frequently observed condition in children. We analyzed the initial manifestations and clinical course. PATIENTS AND METHODS: We restrospectively studied 49 cases of mastocytosis in children (29 boys and 20 girls) managed in our unit between 1985 and 1995. All of the children had typical manifestations. Photographic documents were available in all cases. RESULTS: There was pigmentary urticaria in 32 cases and a mastocytoma in 17. Axanthelasmoid aspect and bullae were observed in some cases in both of these clinical forms. Complementary explorations demonstrated one case of duodenal mast cell infiltration. Excepting the case with skin and duodenal manifestation, all of our patients improved and clinical cure was obtained during growth. DISCUSSION: The association of dermal atopia and mastocytosis does not influence the clinical course of these two conditions. The development of bullae does not appear to be a factor of poor prognosis. The xanthelasmoid aspect of the lesions and the similar course in childhood mastocytosis and juvenile xanthogranulma would suggest that a common process with a histological spectrum including mastocytoma and xanthoma is involved. In our experience, counselling against the use of anti-cough medicines containing codeine is an essential part of management. Antihistamine agents may be prescribed for pruritus.

[Systemic mastocytosis]. / Systemás mastocytosis.

The systemic mastocytosis is a rare disorder, however, the authors recently diagnosed two cases causing diagnostic problems. The diagnosis was proved by bone marrow biopsy in both patients. The authors review the diagnostic pathway considering the pitfalls. According to their conclusion, the most important factor in the diagnosis of systemic mastocytosis is to think of the possibility of systemic mastocytosis.

Biology, classification and treatment of human mastocytosis.

Mastocytosis is a term collectively used for a heterogeneous group of disorders characterized by abnormal growth and accumulation of mast cells. Clinical symptoms occur from the release of chemical mediators and the pathologic infiltration of cells. Three major groups of patients with mastocytosis can be distinguished: i) cutaneous mastocytosis, ii) mastocytosis involving the skin and one or more extracutaneous organ(s), and iii) visceral mastocytosis without involvement of the skin. Groups ii) and iii) account for approximately 15-20% of all cases and have been referred to as systemic mastocytosis. Cutaneous mastocytosis typically presents as urticaria pigmentosa or diffuse cutaneous mastocytosis. These patients usually have a benign course. In contrast, systemic mastocytosis is a diffuse hematologic process with an increased risk to develop aggressive disease. In these patients, additional hematologic abnormalities or a second hematologic process, such as a myeloproliferative or myelodysplastic syndrome, or acute leukemia, may develop. Malignant mastocytosis and mast cell leukemia are rare forms of mastocytosis and characterized by uncontrolled and progressive proliferation and infiltration of mast cells in diverse organs. These patients often present without cutaneous lesions and have a very unfavorable prognosis. Because of the immature morphology of the cells it is often difficult to establish the diagnosis in such patients. However, the use of antibodies to mast cell antigens has recently improved the diagnostic efficiency in patients with suspected mast cell disease. No effective therapy for patients with malignant mastocytosis is known, although some patients may benefit from corticosteroid and interferon alpha treatment. The present article gives an overview of current knowledge about the biology, heterogeneity and treatment of human mastocytosis.

[Immunologic studies in chronic urticaria]. / Immunológiai vizsgálatok chronicus urticariában.

Chronic urticaria is considered to be a heterogeneous disease, which can be divided into several subclasses. The authors investigated 126 patients suffering from chronic urticaria with 41 of unknown origin. The aim of the present study was to work out a strategy for the complete investigation of patients with chronic urticaria. The findings of the immunological study modified the results obtained by medical assessment of the 126 chronic urticaria cases, diminished the number of the patient with chronic urticaria unknown etiology.

[Cutaneous mastocytosis with bullous changes simulating xanthoma tuberosum]. / Mastocytoza skórna ze zmianami guzowatymi imitujacymi xanthoma tuberosum.

A 20-year-old female patient is reported with urticaria pigmentosa and coexisting nodules (mastocytoma) resembling clinically lesions of the type of xanthoma tuberosum. An analysis of microscopic image and ultrastructural changes was carried out and modern views on treatment of cutaneous mastocytosis are discussed.

Mastocytosis.

Mastocytosis implies involvement by excessive numbers of mast cells, of skin and/or other organs. Symptoms may be absent to severe, even occasionally life-threatening. H1- and H2-blocking agents potentially may relieve symptoms, but do nothing to prevent systemization. At present no specific combination chemotherapy regimen has been shown to be markedly effective in a large controlled study. Mithramycin may be of benefit in relieving localized bone pain, although confirmation of this observation in large numbers of patients is needed. PUVA may be a viable approach to symptomatic treatment of otherwise poorly controlled urticaria pigmentosa. In children, urticaria pigmentosa is a relatively benign disease without an increased risk of later systemic involvement. In adults, however, other organs by be involved, with resultant increased morbidity and mortality. Without specific symptoms to a particular organ system, elaborate and expensive staging work-up is not indicated, at least until there is evidence that a reproducibly effective therapy for systemic disease exists.