The authors have declared that no competing interests exist.
Mastocytosis is configured of monomorphic population of atypical mast cells admixed with a minimalistic population of eosinophils. Cutaneous mastocytosis is a frequently discerned mast cell disorder. Urticaria pigmentosa is a commonly discerned variant of mastocytosis exemplifying innumerable miniature, yellow brown papules which convert into hives upon abrasion.
Telangiectasia macularis eruptive perstans (TMEP) is a condition delineating light brown or dark brown cutaneous macules associated with telangiectasia. Previously designated as urticaria pigmentosa, maculopapular cutaneous mastocytosis is a frequently delineated variant occurring within adults or paediatric subjects.
Cutaneous mastocytosis may emerge at birth or during initial three months of infant life. Lesions are associated with flushing attacks on account of elevated content of histamine. Lesions may frequently undergo spontaneous involution. Cutaneous mastocytosis is associated with genomic mutations within CD117 gene
Telangiectasia macularis eruptive perstans demonstrates subtle microscopic features with elevated mast cells circumscribing distended superficial capillaries. Mast cell aggregates appear admixed with superficially disseminated lymphoid and histiocytic inflammatory infiltrate. Superimposed epidermal layer exhibits hyperpigmentation of basal cell layer
Mast cells configuring lesions of maculopapular cutaneous mastocytosis can be highlighted with specific Darier's sign is constituted of a ‘stroking skin’ which releases histamine with the generation of hives. Dermatographism is constituted of dermal oedema simulating hives, a feature which arises due to stroking the cutaneous surface with a pointed instrument. stains as Giemsa, toluidine blue, tryptase or Leder’s special chloroacetate esterase stain. Toluidine blue and Giemsa demonstrate metachromasia within mast cells wherein granules appear purple red. Mast cells appear immune reactive to CD117 (c-KIT)
•cutaneous mastocytosis |
~maculopapular cutaneous mastocytosis(urticarial pigmentosa) |
~diffuse cutaneous mastocytosis |
~mastocytoma of skin |
•systemic mastocytosis |
~indolent systemic mastocytosis |
~smouldering systemic mastocytosis |
~systemic mastocytosis with associated haematological neoplasm or systemic mastocytosis associated with clonal hematologic non mast cell lineage disease |
~aggressive systemic mastocytosis |
~mast cell leukaemia |
•mast cell sarcoma |
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|
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Maculopapular cutaneous mastocytosis | Typically pigmented cutaneous lesions. Darier’s sign+. |
Urticaria pigmentosa | Confirmatory histology. KIT mutation in lesional skin. |
~monomorphic variant | Monomorphic cutaneous lesions |
~polymorphic variant | Polymorphic cutaneous lesions. Absent features of systemic mastocytosis. |
Diffuse cutaneous mastocytosis | Confirmatory histology. Darier’s sign+. Incrimination of entire cutaneous surface. Absent features of systemic mastocytosis |
Cutaneous mastocytoma | Confirmatory histology. Darier’s sign+ |
~isolated mastocytoma | Singular lesion |
~multi-localized mastocytoma | Multiple (2 to 3) lesions. Absent features of systemic mastocytosis |
Cutaneous mastocytosis requires segregation from normal cutaneous surfaces or conditions such as dermatosis, chronic dermatitis, nodular prurigo, venous stasis, bullous impetigo, urticaria, juvenile xanthogranuloma, arthropod stings or autoimmune bullous diseases
Maculopapular cutaneous mastocytosis necessitates distinction from Langerhans cell histiocytosis or urticarial
Cutaneous mastocytosis can be appropriately managed with symptomatic therapy. Topical agents as calcineurin inhibitors or corticosteroids may be optimally adopted to treat the condition. Efficacious systemic therapy is preponderantly comprised of oral antihistamines. Besides, agents such as oral cromolyn sodium, oral corticosteroids, omalizumab, oral psoralen and ultraviolet A(PUVA), narrowband ultraviolet B or ultraviolet A1(UVA1) radiation may be beneficially employed
The cutaneous variant may exceptionally engender systemic mastocytosis with dissemination into >singular soft tissue sites.
Cutaneous mastocytosis is associated with superior prognostic outcomes