Spanish Network on Mastocytosis (REMA) Score

When to use

• Symptomatic patients (e.g., recurrent anaphylaxis or severe mast cell activation episodes) without skin lesions of mastocytosis, to decide who warrants bone marrow evaluation for clonal mast cell disease.

Formula

REMA score = sex points + skin-symptom points + presyncope/syncope points + tryptase points, where: male +1, female -1; urticaria/hives/angioedema present -2, absent +1; presyncope or syncope present +3, absent 0; baseline serum tryptase <15 ng/mL -1, 15-25 ng/mL 0, >25 ng/mL +2. A total score >=2 indicates high probability of clonal mast cell disease.

Pearls and pitfalls

• Developed in patients presenting with mast cell activation/anaphylaxis symptoms who lack the skin lesions typical of mastocytosis.
• Absence of urticaria/angioedema during episodes, rather than their presence, favours an underlying clonal mast cell disorder.

References

1. Alvarez-Twose I, Gonzalez de Olano D, Sanchez-Munoz L, et al. Clinical, biological, and molecular characteristics of clonal mast cell disorders presenting with systemic mast cell activation symptoms. J Allergy Clin Immunol. 2010;125(6):1269-1278.e2.
2. Alvarez-Twose I, Gonzalez-de-Olano D, Sanchez-Munoz L, et al. Validation of the REMA score for predicting mast cell clonality and systemic mastocytosis in patients with systemic mast cell activation symptoms. Int Arch Allergy Immunol. 2012;157(3):275-80.