Recognizing hallmark symptoms may help with earlier identification of SM¹

Skin lesions, anaphylaxis, diarrhea?
Suspect systemic mastocytosis (SM)

Symptoms of SM can mimic other disorders

Select each circle to see how these disorders are different than SM

Cutaneous
mastocytosis

Cutaneous mastocytosis^2-5

The skin is the only site of involvement in CM, whereas SM affects other organs besides skin.

97% of patients (N=59) presenting with adult-onset CM actually have SM.*

Mast cell activation syndrome

Mast cell activation
syndrome^2,6

Bone marrow biopsies for patients with MCAS may show 1 or 2 minor criteria for SM but do not fulfill the complete
WHO criteria.

A full diagnostic workup, including high-sensitivity KIT D816V testing, could help in making a differential diagnosis.

Urticaria

Urticaria²

Urticaria pigmentosa is thought to be a self-resolving condition. Unlike forms of mastocytosis, there is rarely any internal organ involvement, as would be found in patients with SM.

IBD/IBS

IBD/IBS^2,3,7

SM can cause GI symptoms similar to IBD, but mast cells may only mildly increase with IBD and aggregates of mast cells would not be observed.

Myeloproliferative

Myeloproliferative^2,6,8,9

~70% of patients with advanced SM have an associated neoplasm (CMML, MPN, MDS). A specific diagnosis for SM requires a number of laboratory studies, including a high-sensitivity KIT D816V assay.

Malabsorption

Malabsorption^3,7

GI symptoms are present in 60%–80%
of SM patients.

SM-related GI symptoms are largely caused by release of mediators and in rare, advanced forms by mast cell infiltration of the gut causing malabsorption.

Endocrine disorders

Endocrine disorders^2,10

While endocrine disorders can cause flushing, recurrent, unexplained flushing may raise suspicion for SM.

Review case studies
to see how high-sensitivity
KIT D816V testing can help
confirm SM⁶

*Based on a study with 59 patients with the clinical diagnosis of adult-onset mastocytosis in the skin established between 2004 and 2008.⁵
CM=cutaneous mastocytosis; CMML=chronic myelomonocytic leukemia; GI=gastrointestinal; IBD=inflammatory bowel disease; IBS=irritable bowel syndrome;
MCAS=mast cell activation syndrome; MDS=myelodysplastic syndrome; MPN=myeloproliferative neoplasm.

High-sensitivity KIT D816V testing can be used as a first step to evaluate SM upon clinical suspicion⁶

Additional testing is required for diagnosis and subtyping.

Suspect SM?¹

Presence of:
Hallmark symptoms
(skin lesions, anaphylaxis, diarrhea)
Symptoms of mast cell activation
Elevated serum tryptase

Test for a leading indicator in diagnosis of SM⁶

High-sensitivity KIT D816V testing
(eg, ASO-qPCR or ddPCR)⁶

KIT D816V is the main driver of disease in ~95% of SM cases^11-13

Patients who test positive
for KIT D816V using
high-sensitivity KIT testing have an increased
likelihood of SM^6,11-13

Serum tryptase should always be measured in patients with
suspected SM.¹⁴

ASO-qPCR=allele-specific oligonucleotide quantitative polymerase chain reaction; ddPCR=droplet digital PCR.

Did you know?

Low-sensitivity assays may fail to detect the KIT D816V mutation and potentially prolong diagnosis⁶

FIND A LAB

Explore case studies of the types of patients
you may see in your practice

The profiles below are examples of different patient types, which may help you recognize patients in your practice who may be at risk of SM. Patient profiles are fictionalized through review of published literature and are not actual patients.

Select each of the cases below
to learn more