Important Changes in Mastocytosis Classifications

Knowledgeable experts in the study of mastocytosis recently issued a report, introducing changes in terminology and suggesting outcomes based on their clinical observations.  Below is an abstract of the report with a list of the authors/contributors.

J Allergy Clin Immunol. 2016 Jan;137(1):35-45. doi: 10.1016/j.jaci.2015.08.034. Epub 2015 Oct 21.

Cutaneous manifestations in patients with mastocytosis: Consensus report of the European Competence Network on Mastocytosis; the American Academy of Allergy, Asthma & Immunology; and the European Academy of Allergology and Clinical Immunology.

Hartmann K1, Escribano L2, Grattan C3, Brockow K4, Carter MC5, Alvarez-Twose I6, Matito A6, Broesby-Olsen S7, Siebenhaar F8, Lange M9, Niedoszytko M10, Castells M11, Oude Elberink JN12, Bonadonna P13, Zanotti R14, Hornick JL15, Torrelo A16, Grabbe J17, Rabenhorst A18, Nedoszytko B9, Butterfield JH19, Gotlib J20, Reiter A21, Radia D22, Hermine O23, Sotlar K24, George TI25, Kristensen TK26, Kluin-Nelemans HC27, Yavuz S28, Hägglund H29, Sperr WR30, Schwartz LB31, Triggiani M32, Maurer M8, Nilsson G33, Horny HP24, Arock M34, Orfao A2, Metcalfe DD5, Akin C11, Valent P30.

Author information

Abstract

Cutaneous lesions in patients with mastocytosis are highly heterogeneous and encompass localized and disseminated forms. Although a classification and criteria for cutaneous mastocytosis (CM) have been proposed, there remains a need to better define subforms of cutaneous manifestations in patients with mastocytosis. To address this unmet need, an international task force involving experts from different organizations (including the European Competence Network on Mastocytosis; the American Academy of Allergy, Asthma & Immunology; and the European Academy of Allergology and Clinical Immunology) met several times between 2010 and 2014 to discuss the classification and criteria for diagnosis of cutaneous manifestations in patients with mastocytosis. This article provides the major outcomes of these meetings and a proposal for a revised definition and criteria. In particular, we recommend that the typical maculopapular cutaneous lesions (urticaria pigmentosa) should be subdivided into 2 variants, namely a monomorphic variant with small maculopapular lesions, which is typically seen in adult patients, and a polymorphic variant with larger lesions of variable size and shape, which is typically seen in pediatric patients. Clinical observations suggest that the monomorphic variant, if it develops in children, often persists into adulthood, whereas the polymorphic variant may resolve around puberty. This delineation might have important prognostic implications, and its implementation in diagnostic algorithms and future mastocytosis classifications is recommended. Refinements are also suggested for the diagnostic criteria of CM, removal of telangiectasia macularis eruptiva perstans from the current classification of CM, and removal of the adjunct solitary from the term solitary mastocytoma.

Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

What does this mean for our children with cutaneous mastocytosis?

 Urticaria Pigmentosa (UP) is now referred to as maculopapular cutaneous lesions and is divided into two types:

1.    Small spots which vary little in size and shape (monomorphic)

a.    These usually occur in adults

b.    When they occur in children, they may persist into adulthood

2.    Larger spots of various sizes and shapes (polymorphic)

a.    These usually resolve by puberty

Solitary Mastocytoma in now known simply as Mastocytoma